<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE article  PUBLIC "-//NLM//DTD Journal Publishing DTD v3.0 20080202//EN" "http://dtd.nlm.nih.gov/publishing/3.0/journalpublishing3.dtd"><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" dtd-version="3.0" xml:lang="en" article-type="research article"><front><journal-meta><journal-id journal-id-type="publisher-id">CC</journal-id><journal-title-group><journal-title>Computational Chemistry</journal-title></journal-title-group><issn pub-type="epub">2332-5968</issn><publisher><publisher-name>Scientific Research Publishing</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.4236/cc.2016.42004</article-id><article-id pub-id-type="publisher-id">CC-66069</article-id><article-categories><subj-group subj-group-type="heading"><subject>Articles</subject></subj-group><subj-group subj-group-type="Discipline-v2"><subject>Chemistry&amp;Materials Science</subject></subj-group></article-categories><title-group><article-title>
 
 
  DFT-Quantum Spectroscopic Studies and Anti-Cancer Effect of Ibuprofen Drug and Some Analogues
 
</article-title></title-group><contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>nwar</surname><given-names>El- Shahawy</given-names></name><xref ref-type="aff" rid="aff1"><sup>1</sup></xref><xref ref-type="corresp" rid="cor1"><sup>*</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Hana</surname><given-names>Gashlan</given-names></name><xref ref-type="aff" rid="aff2"><sup>2</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Safaa</surname><given-names>Qusti</given-names></name><xref ref-type="aff" rid="aff2"><sup>2</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Ghada</surname><given-names>Ezzat</given-names></name><xref ref-type="aff" rid="aff3"><sup>3</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Hossam</surname><given-names>Emara</given-names></name><xref ref-type="aff" rid="aff1"><sup>1</sup></xref></contrib></contrib-group><aff id="aff3"><addr-line>Biochemistry Department, Faculty of Medicine, Assiut University, Assiut, Egypt</addr-line></aff><aff id="aff2"><addr-line>Biochemistry Department, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia</addr-line></aff><aff id="aff1"><addr-line>Chemistry Department, Faculty of Science, Assiut University, Assiut, Egypt</addr-line></aff><author-notes><corresp id="cor1">* E-mail:<email>anwarshahawy@gmail.com(NES)</email>;</corresp></author-notes><pub-date pub-type="epub"><day>28</day><month>04</month><year>2016</year></pub-date><volume>04</volume><issue>02</issue><fpage>33</fpage><lpage>50</lpage><history><date date-type="received"><day>12</day>	<month>March</month>	<year>2016</year></date><date date-type="rev-recd"><day>accepted</day>	<month>25</month>	<year>April</year>	</date><date date-type="accepted"><day>28</day>	<month>April</month>	<year>2016</year></date></history><permissions><copyright-statement>&#169; Copyright  2014 by authors and Scientific Research Publishing Inc. </copyright-statement><copyright-year>2014</copyright-year><license><license-p>This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/</license-p></license></permissions><abstract><p>
 
 
  From our DFT calculations of Ibuprofen drug (IBF) and other related molecules such as 2-Phenylpropanoic acid (2-PPA) and 3-Phenylpropanoic acid (3-PPA), it has been found that the ionization potential energies of their anions are decreased strongly, with respect to their values in the molecular forms, rendering them as spontaneous electron donor which can compensate the electron deficiency for the positive cancer cells. Time dependent calculations show good coincidence with the experimental absorption spectra. Some complexes of IBF are prepared with Cu
  <sup>++</sup> and Zn
  <sup>++</sup> ions. The ratio between the M
  <sup>++</sup> and the ligand (IBF) is 1:2 which has been verified by atomic absorption spectra and elemental analyses. Their spectral studies have been performed in different solvents of different polarities. The metabolite products of IBF have been studied from DFT calculations point of view and it has been concluded that the consistency of the ionization constants and the electron affinities of them with those of the nucleic acid bases prevents the electron transfer between them therefore they are safe for the human body from cancer diseases.
 
</p></abstract><kwd-group><kwd>DFT/6-31G**</kwd><kwd> IBF</kwd><kwd> 2PPA</kwd><kwd> 3PPA</kwd><kwd> Anions</kwd><kwd> Cu&lt;sup&gt;+&lt;/sup&gt;&lt;sup&gt;+&lt;/sup&gt;</kwd><kwd> Zn&lt;sup&gt;+&lt;/sup&gt;&lt;sup&gt;+&lt;/sup&gt;</kwd><kwd> Cancer</kwd><kwd> UVspectra</kwd></kwd-group></article-meta></front><body><sec id="s1"><title>1. Introduction</title><p>Cancer is a leading cause of death in both more and less economically developed countries due to tobacco use, obesity, physical inactivity, and infections [<xref ref-type="bibr" rid="scirp.66069-ref1">1</xref>] . Ibuprofen drug is a member of the class of drugs termed as non-steroidal anti-inflammatory drugs (NSAIDS), with anti-inflammatory, analgesic, and antipyretic activity. Recently, the regular use of ibuprofen prevents from some certain cancers including prostate, colon, breast, lung, and gastric cancers due to the inhibition of cyclooxygenase-2(COX-2) [<xref ref-type="bibr" rid="scirp.66069-ref2">2</xref>] [<xref ref-type="bibr" rid="scirp.66069-ref3">3</xref>] . Reduced Risk of Human Lung Cancer by Selective Cyclooxygenase 2 (Cox-2) Blockade was studied by Harris et al. [<xref ref-type="bibr" rid="scirp.66069-ref4">4</xref>] . The 2-arylpropanoic acids (2-APAs) are an important group of non-steroidal anti-inflammatory drugs, the majority of which are remarked as racemic mixtures because they have asymmetric carbon atom. These drugs exhibit stereoselectivity in both their pharmacological activity, i.e. inhibition of cyclo-oxygenase [<xref ref-type="bibr" rid="scirp.66069-ref5">5</xref>] . The lattice energy of ibuprofen crystals which is calculated using DFT method agrees with the experimental values especially with polymorphism of the crystals [<xref ref-type="bibr" rid="scirp.66069-ref6">6</xref>] . The conformational stability of ibuprofen, due to a para-substituted group in the molecule, is carried out using DFT calculations coupled with optical vibrational spectroscopy. The calculated frequencies and intensities prove the presence of the lowest energy conformers in the solid state and intermolecular hydrogen bonds between the carboxylic groups of adjacent molecules leading to formation of dimmers [<xref ref-type="bibr" rid="scirp.66069-ref7">7</xref>] . In the frame of theoretical studies of ibuprofen, the action of ibuprofen is due to electrophilic attack on the oxygen atoms of carboxyl group [<xref ref-type="bibr" rid="scirp.66069-ref8">8</xref>] . The superior DFT methods in predicting the structures of ibuprofen are mPW1PW91/6-311++G (d, p) and mPW1PW91/6-311++G (2d, 2p) while B3PW91/6-311++G (2d, 2p) is the best method to predict all vibrational frequencies of the molecule [<xref ref-type="bibr" rid="scirp.66069-ref9">9</xref>] . In this work, it has been suggested that the anti-cancer effect of the ibuprofen and its analogues is due to their anionic and molecular forms of the drug side by side in the human body specifically for the positive cancer cells.</p></sec><sec id="s2"><title>2. Experimental Work</title><sec id="s2_1"><title>2.1. Apparatuses</title><p>All melting points of the studied compounds have been determined on a Gallen-Kamp melting point apparatus.</p><p>The elemental analyses (C, H, N) were determined using Elementer Analyses system (GmbH, Donaustr-7, D-63452) Hanau, (Germany).</p><p>The electronic absorption spectra of the studied compounds had been scanned by uv-2011 PC, uv-vis scanning spectrophotometer (Shimadzu) using 1 cm matched silica cells.</p><p>The atomic absorption spectra of the complexes were studied by using an atomic absorption spectrophotometer (Buck Scientific Model 210 GVP).</p></sec><sec id="s2_2"><title>2.2. Materials and Methods</title><p>All materials supplied to our experimental work were bought from the different companies without further purification. Ibuprofen (IBF) was bought from Sigma Aldrich and 2-Phenylpropanoic acid (2-PPA) was bought from Alfa Aesar as well as 3-Phenylpropanoic acid (3-PPA).</p><p>Ibuprofen (2.06 g, 0.01 moles) was allowed to be dissolved in a solution of potassium bicarbonate (1.10 g, 0.011 mole) in 80 ml of water. During stirring the solution, CuSO<sub>4</sub>・5H<sub>2</sub>O was added slowly (1.25 g, 0.005 mole) in 10 ml of water. The mixture was allowed to be stirred for 30 minutes. The aquamarine precipitated and was collected, washed with water followed by ethanol, and then recrystallized from ether. The product was air-dried, [<xref ref-type="bibr" rid="scirp.66069-ref10">10</xref>] .</p><p>2.0 Mmoles (0.412 g) of ibuprofen react with 2.0 mmoles (0.112 g) of KOH dissolved in 20 mL of distilled water, to give the potassium salt of the ligand. Then 1.0 mmole (0.2195 g) of Zn(CH<sub>3</sub>COO)<sub>2</sub>・2H<sub>2</sub>O (aqueous solution) was added during stirring. The white needle precipitated and collected by filtration, washed several times with distilled water and acetone, then dried in vacuum, [<xref ref-type="bibr" rid="scirp.66069-ref11">11</xref>] . The melting points of the studied compounds have been presented in <xref ref-type="table" rid="table1">Table 1</xref>.</p><p>From elemental analysis, <xref ref-type="table" rid="table2">Table 2</xref>, and atomic absorption spectra, <xref ref-type="table" rid="table3">Table 3</xref> it has been shown that the ratio between metal ions, Cu<sup>++</sup> or Zn<sup>++</sup> with IBF ligand is 1:2 in their complexes.</p></sec></sec><sec id="s3"><title>3. Method of Calculations</title><sec id="s3_1"><title>3.1. Spectral Constants</title><p>The absolute intensity of band absorption can be calculated and it has been shown that Einstein transition probabilities coefficients, [<xref ref-type="bibr" rid="scirp.66069-ref12">12</xref>] [<xref ref-type="bibr" rid="scirp.66069-ref13">13</xref>] of the emission, A, and the absorption, B, between two electronic states i.e. the</p><table-wrap id="table1" ><label><xref ref-type="table" rid="table1">Table 1</xref></label><caption><title> Melting points of ibuprofen, 3-PPA, Copper(II) and Zinc(II) comp- lexes with ibuprofen</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Compound</th><th align="center" valign="middle" >Melting point range ˚C</th></tr></thead><tr><td align="center" valign="middle" >IBF</td><td align="center" valign="middle" >74 - 76</td></tr><tr><td align="center" valign="middle" >3-PPA</td><td align="center" valign="middle" >44 - 48</td></tr><tr><td align="center" valign="middle" >Cu(IBF)<sub>2</sub></td><td align="center" valign="middle" >250 - 252</td></tr><tr><td align="center" valign="middle" >Zn(IBF)<sub>2</sub>・2H<sub>2</sub>O</td><td align="center" valign="middle" >78 - 82</td></tr></tbody></table></table-wrap><table-wrap id="table2" ><label><xref ref-type="table" rid="table2">Table 2</xref></label><caption><title> Elemental analysis of Copper(II) and Zinc(II) complexes with Ibu- profen</title></caption><table><tbody><thead><tr><th align="center" valign="middle"  rowspan="2"  >Compound</th><th align="center" valign="middle"  colspan="2"  >% Theoretical</th><th align="center" valign="middle"  colspan="2"  >% Experimental</th></tr></thead><tr><td align="center" valign="middle" >C</td><td align="center" valign="middle" >H</td><td align="center" valign="middle" >C</td><td align="center" valign="middle" >H</td></tr><tr><td align="center" valign="middle" >Cu(IBF)<sub>2</sub></td><td align="center" valign="middle" >65.87</td><td align="center" valign="middle" >7.23</td><td align="center" valign="middle" >63.74</td><td align="center" valign="middle" >6.55</td></tr><tr><td align="center" valign="middle" >Zn(IBF)<sub>2</sub>・2H<sub>2</sub>O</td><td align="center" valign="middle" >60.10</td><td align="center" valign="middle" >7.48</td><td align="center" valign="middle" >60.40</td><td align="center" valign="middle" >7.44</td></tr></tbody></table></table-wrap><table-wrap id="table3" ><label><xref ref-type="table" rid="table3">Table 3</xref></label><caption><title> Atomic absorption of Copper(II) and zinc(II) complexes with Ibu- profen</title></caption><table><tbody><thead><tr><th align="center" valign="middle"  rowspan="2"  >Compound</th><th align="center" valign="middle" >% Theoretical</th><th align="center" valign="middle" >% Experimental</th></tr></thead><tr><td align="center" valign="middle" >M<sup>+2</sup></td><td align="center" valign="middle" >M<sup>+2</sup></td></tr><tr><td align="center" valign="middle" >Cu(IBF)<sub>2</sub></td><td align="center" valign="middle" >13.40</td><td align="center" valign="middle" >12.95</td></tr><tr><td align="center" valign="middle" >Zn(IBF)<sub>2</sub>・2H<sub>2</sub>O</td><td align="center" valign="middle" >12.77</td><td align="center" valign="middle" >12.1</td></tr></tbody></table></table-wrap><p>ground state I, and the excited state f, are given as follows:</p><disp-formula id="scirp.66069-formula33"><label>(1)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/1-1710047x6.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.66069-formula34"><label>(2)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/1-1710047x7.png"  xlink:type="simple"/></disp-formula><p>where:</p><p>e = The charge of the electron</p><p>h = Planck’s constant</p><p>C = The velocity of light, 3 &#180; 10<sup>10</sup> cm・sec<sup>−1</sup></p><p><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/1-1710047x8.png" xlink:type="simple"/></inline-formula>= The wave number in cm<sup>−1</sup></p><p>G<sub>f</sub> = Degeneracy of the state</p><p>D<sub>if</sub> = Dipole strength</p><p>Substituting the numerical values and assuming that degeneracy of the state is singlet, then:</p><disp-formula id="scirp.66069-formula35"><label>(3)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/1-1710047x9.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.66069-formula36"><label>(4)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/1-1710047x10.png"  xlink:type="simple"/></disp-formula><p>Mulliken related the quantity B<sub>if</sub> to the Oscillator strength, F, which is the measure of the intensity.</p><disp-formula id="scirp.66069-formula37"><label>(5)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/1-1710047x11.png"  xlink:type="simple"/></disp-formula><p>Also the Oscillator strength can be related to the absolute intensity as follows:</p><disp-formula id="scirp.66069-formula38"><label>(6)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/1-1710047x12.png"  xlink:type="simple"/></disp-formula><p>where: m = The mass of electron</p><p>N = The Avogadro’s number</p><p>e = Molar extinction coefficient</p><p>if a molecule or an atom is in an excited state then, in the absence of an external electromagnetic field, on the average, after a time of <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/1-1710047x13.png" xlink:type="simple"/></inline-formula> where A<sub>if</sub> is the Einstein spontaneous transition probability coefficient from the</p><p>excited state to the ground state, it will emit a photon. <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/1-1710047x14.png" xlink:type="simple"/></inline-formula>is called the mean lifetime of the excited state. Generally D<sub>if</sub> can be calculated numerically as follows:</p><disp-formula id="scirp.66069-formula39"><label>. (7)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/1-1710047x15.png"  xlink:type="simple"/></disp-formula><p>where <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/1-1710047x16.png" xlink:type="simple"/></inline-formula> is the half width of the absorption band in cm<sup>−1</sup>. hence, the oscillator strength can be calculated directly as follows:</p><disp-formula id="scirp.66069-formula40"><label>(8)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/1-1710047x17.png"  xlink:type="simple"/></disp-formula></sec><sec id="s3_2"><title>3.2. DFT Calculations</title><p>Computational studies on the isolated molecules in the gas phase were performed by the aid of GAUSSIAN 03 package. Minimum energy structures have been achieved using semi-empirical AM1 method. DFT/6-31**G calculations were performed on the minimum energy structures using the closed shell Hartree-Fock, Becke’s three parameters density functional theory, DFT, [<xref ref-type="bibr" rid="scirp.66069-ref12">12</xref>] [<xref ref-type="bibr" rid="scirp.66069-ref13">13</xref>] in combination with the Lee, Yang and Parr correlation functional B3LYP. The differentiation between the conformers’ R and S of the ibuprofen drug was based on the total energy difference which has been calculated via SCF using RHF for these types of molecules and UHF for the molecular anions.</p><p>With respect to DFT calculations, it has been carried out as B3LYP/6-31**G and the energy of the DFT theory can be represented as a function of the electron density as follows:</p><disp-formula id="scirp.66069-formula41"><graphic  xlink:href="http://html.scirp.org/file/1-1710047x18.png"  xlink:type="simple"/></disp-formula><p>where <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/1-1710047x19.png" xlink:type="simple"/></inline-formula> is the electron density</p><disp-formula id="scirp.66069-formula42"><graphic  xlink:href="http://html.scirp.org/file/1-1710047x20.png"  xlink:type="simple"/></disp-formula><p>where C<sub>i</sub> is the eigenvectors for each eigenfunction Ψ<sub>i</sub> and</p><p><img data-original="http://html.scirp.org/file/1-1710047x23.png" /><img data-original="http://html.scirp.org/file/1-1710047x22.png" /><img data-original="http://html.scirp.org/file/1-1710047x21.png" /></p><p>where <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/1-1710047x24.png" xlink:type="simple"/></inline-formula> is the total energy Hamiltonian operator. ε is the permittivity of the vacuum.</p></sec></sec><sec id="s4"><title>4. Results and Discussion</title><sec id="s4_1"><title>4.1. Spectroscopic Studies</title><p>Ibuprofen, 2 (4-isobutylphenylpropanoic acid (IBF), is a non-steroidal anti-inflammatory drug (NSAID) which can be used for relieving pain, antipyretic and anti-inflammatory. About 60% of patients improve with any given NSAID and it is advised that if one does not work that another can be used. Ibuprofen may be considered as weak anti-inflammatory than other NSAIDs. IBF molecule has two conformers R and S as shown in the following <xref ref-type="fig" rid="fig1">Figure 1</xref>. Ibuprofen has a particularly interesting property, and it can exist as a pair of optical isomers that</p><fig-group id="fig1"><label><xref ref-type="fig" rid="fig1">Figure 1</xref></label><caption><title> Minimum energy structures of Ibuprofen isomers.</title></caption><fig id ="fig1_1"><label></label><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/1-1710047x25.png"/></fig><fig id ="fig1_2"><label></label><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/1-1710047x26.png"/></fig></fig-group><p>are mirror images of each other. These mirror images are non-super-imposable, which are mirror images but not identical. This mirror image property occurs in molecules that have asymmetric carbon atom. The two optical isomers of ibuprofen are identified by the prefixes R<sup>−</sup> (Levo Rotatory) and S<sup>+</sup> (Dextro Rotatory). DFT calculations have been performed according to El-Shahawy, [<xref ref-type="bibr" rid="scirp.66069-ref12">12</xref>] [<xref ref-type="bibr" rid="scirp.66069-ref13">13</xref>] using the basis set 6-31**G.</p><p>From the previous <xref ref-type="table" rid="table4">Table 4</xref>, it has been shown that the energy difference between the S and R forms is very small being equal to 0.02839 eV which is too small to make a significant difference in the temperature effect, <xref ref-type="fig" rid="fig2">Figure 2</xref>, on the spectrum in ethanol solvent, [<xref ref-type="bibr" rid="scirp.66069-ref14">14</xref>] . Therefore IBF molecules exist in the two forms in a racemic mixture. From the energy difference between the two forms it has been calculated that the ratio between them equal 0.35 of the S-conformer of higher energy this means that the R-form is the predominant form in the IBF drug i.e. 65% at 37˚C. The two forms have nearly the same constants of ionization potential, Ip, and electron affinity Ea, except the dipole moment of the S-form is higher than that of R-form.</p><p>From the previous <xref ref-type="table" rid="table5">Table 5</xref>, it can be concluded that the IBF molecule, even S or R, form has lower energy than those of phenyl derivatives of propanioc acid which have higher ionization potentials than those of IBF forms. The electron affinities of 2-PPA and Zn (IBF)<sub>2</sub> are higher than those of the studied compounds. The S-IBF and 2-PPA have the higher dipole moments among all the other compounds.</p><p>Regarding the HOMO of IBF molecule even in the R and S-forms, it is ψ<sub>m</sub> in each singlet configuration eigenfunctions of the excited states. From the previous <xref ref-type="table" rid="table6">Table 6</xref>, it has been noticed that the first excited state of R-form includes the configurations of transitions ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+1</sub>, ψ<sub>m</sub> → ψ<sub>m</sub><sub>+1</sub>, ψ<sub>m</sub> → ψ<sub>m</sub><sub>+3</sub> and ψ<sub>m</sub> → ψ<sub>m</sub><sub>+4</sub>. The configuration eigenfunction of highest contribution in the first excited state is that includes the transition ψ<sub>m</sub> → Ψ<sub>m</sub><sub>+1</sub> of eigenvector 0.60334. From the previous <xref ref-type="table" rid="table7">Table 7</xref>, it can be noticed that the first excited state of S-form is constituted from the configuration eigenfunctions of transitions ψ<sub>m</sub><sub>−</sub><sub>2</sub> → ψ<sub>m</sub><sub>+1</sub>, ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+5</sub>, ψ<sub>m</sub> → ψ<sub>m</sub><sub>+1</sub> and ψ<sub>m</sub> → ψ<sub>m</sub><sub>+2</sub> and ψ<sub>m</sub> → ψ<sub>m</sub><sub>+5</sub>. The configuration which has high contribution in the transition to the first excited state contains the transition ψ<sub>m</sub> → ψ<sub>m</sub><sub>+1</sub> of eigenvector 0.55621 in case of S-form. In the second singlet excited state of the R-form, the contributions of configuration eigenfunctions containing the transitions ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+1</sub> and ψ<sub>m</sub> → ψ<sub>m</sub><sub>+2</sub> are the highest as well as in case of the S-form, <xref ref-type="table" rid="table6">Table 6</xref>, <xref ref-type="table" rid="table7">Table 7</xref>. For the R-form, the third excited state includes the highest configuration eigenfunction of the transition ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+1</sub> as well as in case of the S-form. It is shown from the previous <xref ref-type="table" rid="table6">Table 6</xref>, <xref ref-type="table" rid="table7">Table 7</xref>, that the first transitions from the ground state to the firs excited state for the two conformers lies at the same wavelength 445 nm which has not any change in the uv-spectrum of IBF drug by the temperature effect [<xref ref-type="bibr" rid="scirp.66069-ref14">14</xref>] .</p><p>From the previous <xref ref-type="fig" rid="fig3">Figure 3</xref> and <xref ref-type="table" rid="table8">Table 8</xref>, of IBF spectra, it has been shown that there is some broadness in the top of the absorption bands in different solvents and of course the temperature effect doesn’t show any change in the relative intensity, <xref ref-type="fig" rid="fig2">Figure 2</xref>, due to the very small energy difference between the two conformers R and S</p><fig id="fig2"  position="float"><label><xref ref-type="fig" rid="fig2">Figure 2</xref></label><caption><title> Electronic spectra of Ibuprofen (403 mmol・L<sup>−1</sup>) in ethanol at different temperature: a = 25˚C; b = 40˚C</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/1-1710047x27.png"/></fig><table-wrap id="table4" ><label><xref ref-type="table" rid="table4">Table 4</xref></label><caption><title> DFT-Data of the optical isomers of IBF in the ground state</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Form of IBF</th><th align="center" valign="middle" >TE au</th><th align="center" valign="middle" >ΔE</th><th align="center" valign="middle" >IP eV</th><th align="center" valign="middle" >Ea</th><th align="center" valign="middle" >Dip. Mom. D</th></tr></thead><tr><td align="center" valign="middle" >S-IBF</td><td align="center" valign="middle" >−656.5408</td><td align="center" valign="middle" >0.0010397 au</td><td align="center" valign="middle" >6.6837</td><td align="center" valign="middle" >0.8879</td><td align="center" valign="middle" >2.2182</td></tr><tr><td align="center" valign="middle" >R-IBF</td><td align="center" valign="middle" >−656.5419</td><td align="center" valign="middle" >0.0282917 eV</td><td align="center" valign="middle" >6.6766</td><td align="center" valign="middle" >0.9048</td><td align="center" valign="middle" >1.4383</td></tr></tbody></table></table-wrap><table-wrap id="table5" ><label><xref ref-type="table" rid="table5">Table 5</xref></label><caption><title> Comparative DFT parameters of Ibuprofen and some analogues</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Compound</th><th align="center" valign="middle" >TE au</th><th align="center" valign="middle" >Ip eV</th><th align="center" valign="middle" >Ea eV</th><th align="center" valign="middle" >Dip. Mom. D</th></tr></thead><tr><td align="center" valign="middle" >S-IBF</td><td align="center" valign="middle" >−656.5408</td><td align="center" valign="middle" >6.6837</td><td align="center" valign="middle" >0.8879</td><td align="center" valign="middle" >2.2182</td></tr><tr><td align="center" valign="middle" >R-IBF</td><td align="center" valign="middle" >−656.5419</td><td align="center" valign="middle" >6.6766</td><td align="center" valign="middle" >0.9048</td><td align="center" valign="middle" >1.4383</td></tr><tr><td align="center" valign="middle" >2-PPA</td><td align="center" valign="middle" >−499.3220</td><td align="center" valign="middle" >7.0146</td><td align="center" valign="middle" >0.9633</td><td align="center" valign="middle" >1.9947</td></tr><tr><td align="center" valign="middle" >3-PPA</td><td align="center" valign="middle" >−499.3209</td><td align="center" valign="middle" >6.8812</td><td align="center" valign="middle" >0.8768</td><td align="center" valign="middle" >1.8931</td></tr><tr><td align="center" valign="middle" >Cu(IBF)2</td><td align="center" valign="middle" >−2952.01917046</td><td align="center" valign="middle" >6.53509</td><td align="center" valign="middle" >1.38397</td><td align="center" valign="middle" >1.6296</td></tr><tr><td align="center" valign="middle" >Zn(IBF)2</td><td align="center" valign="middle" >−3090.86733452</td><td align="center" valign="middle" >6.494817</td><td align="center" valign="middle" >2.479230</td><td align="center" valign="middle" >1.4591</td></tr></tbody></table></table-wrap><p>N.B. 2-PA is 2-phenyl propanioc acid and 3-PA is 3-phenyl propanioc acid. Ip is the ionization potential, Ea is the electron affinity and Dip. Mom. Is dipole moment.</p><table-wrap id="table6" ><label><xref ref-type="table" rid="table6">Table 6</xref></label><caption><title> Excitation energies and oscillator strengths of R-form of IBF in the gaseous state</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Excited State Singlet-A</th><th align="center" valign="middle" >Eigenvectors</th><th align="center" valign="middle" >Transition</th><th align="center" valign="middle" >ΔE eV</th><th align="center" valign="middle" >λ<sub>calc.</sub> nm</th><th align="center" valign="middle" >f</th><th align="center" valign="middle" >λ<sub>exp</sub><sub>.</sub> nm</th></tr></thead><tr><td align="center" valign="middle"  colspan="7"  >Excited State 1</td></tr><tr><td align="center" valign="middle" >54 → 57 56 → 57 56 → 59 56 → 60</td><td align="center" valign="middle" >−0.22953 0.60334 0.11187 0.10821</td><td align="center" valign="middle" >ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub>→ ψ<sub>m</sub><sub>+3</sub> ψ<sub>m</sub>→ ψ<sub>m</sub><sub>+4</sub></td><td align="center" valign="middle" >5.0675</td><td align="center" valign="middle" >245 nm</td><td align="center" valign="middle" >0.0843</td><td align="center" valign="middle" >263 nm</td></tr><tr><td align="center" valign="middle"  colspan="7"  >Excited State 2</td></tr><tr><td align="center" valign="middle" >54 → 57 55 → 57 55 → 60 55 → 61 56 → 58 56 → 59</td><td align="center" valign="middle" >−0.14064 −0.45550 0.10498 −0.10824 0.47239 0.10670</td><td align="center" valign="middle" >ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+4</sub> ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+5</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+2</sub> ψ<sub>m</sub>→ ψ<sub>m</sub><sub>+3</sub></td><td align="center" valign="middle" >5.1952</td><td align="center" valign="middle" >238.65 nm</td><td align="center" valign="middle" >0.0016</td><td align="center" valign="middle" >231 nm</td></tr><tr><td align="center" valign="middle"  colspan="7"  >Excited State 3</td></tr><tr><td align="center" valign="middle" >54 → 57 54 → 59 54 → 60 56 → 57 56 → 58</td><td align="center" valign="middle" >0.56731 0.15448 0.13998 0.26587 0.12041</td><td align="center" valign="middle" >ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+3</sub> ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+4</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+2</sub></td><td align="center" valign="middle" >5.3933</td><td align="center" valign="middle" >229.89</td><td align="center" valign="middle" >0.0177</td><td align="center" valign="middle" ></td></tr></tbody></table></table-wrap><fig id="fig3"  position="float"><label><xref ref-type="fig" rid="fig3">Figure 3</xref></label><caption><title> Electronic spectra of Ibuprofen (403 mmol・L<sup>−1</sup> in) (a) EtOH (b) MeOH, (c) Isopropanol, (d) CHCl<sub>3</sub>, and (e) Cyclohexane</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/1-1710047x28.png"/></fig><table-wrap id="table7" ><label><xref ref-type="table" rid="table7">Table 7</xref></label><caption><title> Excitation energies and oscillator strengths of S-form of IBF in the gas phase</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Excited State Singlet-A</th><th align="center" valign="middle" >Eigenvectors</th><th align="center" valign="middle" >Transition</th><th align="center" valign="middle" >ΔE eV</th><th align="center" valign="middle" >λ<sub>calc.</sub> nm</th><th align="center" valign="middle" >F</th><th align="center" valign="middle" >λ<sub>exp.</sub> nm</th></tr></thead><tr><td align="center" valign="middle"  colspan="7"  >Excited State 1</td></tr><tr><td align="center" valign="middle" >54 → 57 54 → 61 56 → 57 56 → 58 56 → 61</td><td align="center" valign="middle" >0.29826 −0.11518 0.55621 −0.17879 −0.11978</td><td align="center" valign="middle" >ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+5</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+2</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+5</sub></td><td align="center" valign="middle" >4.9819</td><td align="center" valign="middle" >245 nm</td><td align="center" valign="middle" >0.0658</td><td align="center" valign="middle" >263 nm</td></tr><tr><td align="center" valign="middle"  colspan="7"  >Excited State 2</td></tr><tr><td align="center" valign="middle" >54 → 57 55 → 57 55 → 58 55 → 61 56 → 58 56 → 59 56 → 61</td><td align="center" valign="middle" >0.12731 0.42453 0.10408 0.15894 0.41711 −0.25061 −0.14454</td><td align="center" valign="middle" >ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+2</sub> ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+5</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+5</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+3</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+5</sub></td><td align="center" valign="middle" >5.2043</td><td align="center" valign="middle" >238.24</td><td align="center" valign="middle" >0.0104</td><td align="center" valign="middle" >231 nm</td></tr><tr><td align="center" valign="middle"  colspan="7"  >Excited State 3</td></tr><tr><td align="center" valign="middle" >54 → 57 54 → 58 54 → 61 56 → 57</td><td align="center" valign="middle" >0.52994 −0.12594 −0.17235 −0.34971</td><td align="center" valign="middle" >ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+2</sub> ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+5</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+1</sub></td><td align="center" valign="middle" >5.4852</td><td align="center" valign="middle" >226.03</td><td align="center" valign="middle" >0.0497</td><td align="center" valign="middle" ></td></tr></tbody></table></table-wrap><table-wrap id="table8" ><label><xref ref-type="table" rid="table8">Table 8</xref></label><caption><title> Spectral parameters, Einstein probabilities (A<sub>if</sub> and B<sub>if</sub>), dipole strength (D<sub>if</sub>), oscillator strength (F<sub>if</sub>), lifetime (τ) and extinction coefficient (ε<sub>max</sub>) of the electronic transition bands of Ibuprofen in different solvents</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Solvent</th><th align="center" valign="middle" ><sub>max</sub>λ</th><th align="center" valign="middle" >A<sub>if</sub> 10<sup>−7</sup> S<sup>−</sup><sup>1</sup><sup> </sup></th><th align="center" valign="middle" >B<sub>if</sub> 10<sup>−7</sup> S・g<sup>−</sup><sup>1</sup></th><th align="center" valign="middle" >D<sub>if</sub> 10<sup>18</sup></th><th align="center" valign="middle" >f<sub>if</sub> 10<sup>2</sup></th><th align="center" valign="middle" >ε<sub>max</sub></th><th align="center" valign="middle" >τ ns</th></tr></thead><tr><td align="center" valign="middle"  rowspan="2"  >Ethanol</td><td align="center" valign="middle" >230.05</td><td align="center" valign="middle" >2.45</td><td align="center" valign="middle" >3.00</td><td align="center" valign="middle" >4.14</td><td align="center" valign="middle" >1.95</td><td align="center" valign="middle" >830.78</td><td align="center" valign="middle" >40.82</td></tr><tr><td align="center" valign="middle" >263.51</td><td align="center" valign="middle" >0.455</td><td align="center" valign="middle" >1.67</td><td align="center" valign="middle" >1.15</td><td align="center" valign="middle" >0.476</td><td align="center" valign="middle" >254.41</td><td align="center" valign="middle" >219.78</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Methanol</td><td align="center" valign="middle" >230.89</td><td align="center" valign="middle" >2.13</td><td align="center" valign="middle" >5.28</td><td align="center" valign="middle" >3.64</td><td align="center" valign="middle" >1.71</td><td align="center" valign="middle" >827.39</td><td align="center" valign="middle" >46.95</td></tr><tr><td align="center" valign="middle" >263.68</td><td align="center" valign="middle" >0.457</td><td align="center" valign="middle" >1.68</td><td align="center" valign="middle" >1.16</td><td align="center" valign="middle" >0.478</td><td align="center" valign="middle" >264.90</td><td align="center" valign="middle" >218.82</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Isopropanol</td><td align="center" valign="middle" >230.76</td><td align="center" valign="middle" >2.29</td><td align="center" valign="middle" >5.66</td><td align="center" valign="middle" >3.90</td><td align="center" valign="middle" >1.84</td><td align="center" valign="middle" >855.45</td><td align="center" valign="middle" >43.67</td></tr><tr><td align="center" valign="middle" >263.68</td><td align="center" valign="middle" >0.479</td><td align="center" valign="middle" >1.76</td><td align="center" valign="middle" >1.22</td><td align="center" valign="middle" >0.501</td><td align="center" valign="middle" >273.23</td><td align="center" valign="middle" >208.77</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Cyclohexane</td><td align="center" valign="middle" >231.60</td><td align="center" valign="middle" >2.00</td><td align="center" valign="middle" >4.99</td><td align="center" valign="middle" >3.44</td><td align="center" valign="middle" >1.61</td><td align="center" valign="middle" >822.45</td><td align="center" valign="middle" >50.00</td></tr><tr><td align="center" valign="middle" >263.42</td><td align="center" valign="middle" >0.490</td><td align="center" valign="middle" >1.80</td><td align="center" valign="middle" >1.24</td><td align="center" valign="middle" >0.512</td><td align="center" valign="middle" >277.23</td><td align="center" valign="middle" >204.08</td></tr><tr><td align="center" valign="middle" >Chloroform</td><td align="center" valign="middle" >264.20</td><td align="center" valign="middle" >0.523</td><td align="center" valign="middle" >1.94</td><td align="center" valign="middle" >1.34</td><td align="center" valign="middle" >0.549</td><td align="center" valign="middle" >299.51</td><td align="center" valign="middle" >191.21</td></tr></tbody></table></table-wrap><p>[<xref ref-type="bibr" rid="scirp.66069-ref14">14</xref>] . However, the maximum absorption band positions exist at the same values 231 and 263 nm even by using different solvents with different polarities indicating to non-polarized ground and excited states for this molecule. The Einstein transition probabilities (A<sub>if</sub> and B<sub>if</sub>), oscillator strength f<sub>if</sub>, dipole strength D<sub>if</sub> and the life time of excitation τ between the initial (i) and the final (f) electronic states have been calculated according to El-Shahawy [<xref ref-type="bibr" rid="scirp.66069-ref12">12</xref>] [<xref ref-type="bibr" rid="scirp.66069-ref13">13</xref>] . The spontaneous transition probability A<sub>if</sub>, of IBF spectra in different solvents of different polarity has values which are higher at λ<sub>max</sub> = 231 nm than those at λ<sub>max</sub> = 263 nm as well as the same situation in the values of the induced transition probability, B<sub>if</sub>, of IBF spectra. The dipole strength D<sub>if</sub> values are higher at λ<sub>max</sub> = 231 than those at λ<sub>max</sub> = 263 nm. The absorption bands at λ<sub>max</sub> = 231 nm have higher oscillator strengths f<sub>if</sub> than those at λ<sub>max</sub> = 263 nm and this appears in <xref ref-type="fig" rid="fig3">Figure 3</xref>, that the absorption bands at λ<sub>max</sub> = 231 nm have higher intensities more than those at λ = 263 nm in different solvents. The life time of the electronic excited states τ, of this molecule has average value ~200 ns for the transitions at λ<sub>max</sub> = 263 nm but it has lower average value ~45 ns for the transitions at λ<sub>max</sub> = 231 nm.</p><p>The ultraviolet spectra of 2-Phenylpropanoic acid <xref ref-type="fig" rid="fig4">Figure 4</xref>, show bands at λ = 257 nm and at λ<sub>max</sub> = 228 nm which have the induced transition probability (B<sub>f</sub>) in different solvents being higher than those of the spontaneous transition probability (A<sub>if</sub>) as in the same case of IBF spectra. The molar absoptivities of the two absorption bands at λ<sub>max</sub> = 231 and λ<sub>max</sub> = 263 in the IBF spectra are higher, <xref ref-type="table" rid="table8">Table 8</xref>, than those of absorption bands λ<sub>max</sub> = 228 and λ<sub>max</sub> = 257 nm in the spectra of 2-Phenylpropanoic acid, <xref ref-type="table" rid="table9">Table 9</xref>. The oscillator strengths f<sub>if</sub>, in 2-Phenylpropanoic acid spectra in different solvents are lower than those of IBF spectral bands. The dipole strengths D<sub>if</sub> of 2-Phenylpropanoic acid absorption bands in different solvents are lower than those of IBF but the life times of the excited states of the absorption bands in the spectra of 2-Phenylpropanoic acid are higher than those of IBF spectral bands. From the previous <xref ref-type="table" rid="table1">Table 1</xref>0, the transition energy from the ground state to the first excited state lies at 244 nm which is corresponding to an experimental value at 257 nm, <xref ref-type="table" rid="table9">Table 9</xref>. This first excited state of minimum energy structure of 2-PPA, <xref ref-type="fig" rid="fig5">Figure 5</xref>, is composed from configuration eigenfunctions of the electronic transitions ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+1</sub>, ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+4</sub>, ψ<sub>m</sub> → ψ<sub>m</sub><sub>+1</sub>, ψ<sub>m</sub> → ψ<sub>m</sub><sub>+2</sub> and ψ<sub>m</sub> → ψ<sub>m</sub><sub>+4</sub>. The main configuration eigenfunction in the first excited state having the transition ψ<sub>m</sub>-→ ψ<sub>m</sub><sub>+1</sub> of eigenvector 0.49968. The calculated transition energy to the second excite state at λ = 233 nm has good coincidence with the experimental position at λ = 228 nm and the main configuration eigenfunction of high contribution in the second excited state includes the transition ψ<sub>m</sub><sub>−1−→</sub> ψ<sub>m</sub><sub>+1</sub> of eigenvector 0.49872. The eigenfunction of high contribution in the third excited state includes the transition ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+1</sub> of eigenvector 0.46682.</p><p>The first calculated electronic transition from the ground state to the first singlet state lies at 236 nm which is not far from the experimental maximum wavelength at 259 nm, <xref ref-type="table" rid="table1">Table 1</xref>1. From comparison point of view between the spectral parameters between 2-PPA and 3-PPA it can be noticed that the Einstein transition probabilities (A<sub>if</sub> and B<sub>if</sub>), dipole sstrength D<sub>if</sub> and oscillator strength F<sub>if</sub> of 2-PPA are higher than those of 3-PPA spectral parameters but the life time of excitation of 3-PPA is higher than that of 2-PPA spectral parameters, <xref ref-type="table" rid="table9">Table 9</xref>,</p><fig id="fig4"  position="float"><label><xref ref-type="fig" rid="fig4">Figure 4</xref></label><caption><title> Electronic spectrum of 2-Phenylpropanoic acid (452 mmol・L<sup>−1</sup>) in (a) EtOH, (b) MeOH, (c) Isopropanol, (d) CHCl<sub>3</sub> and (e) Cyclohexane</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/1-1710047x29.png"/></fig><fig id="fig5"  position="float"><label><xref ref-type="fig" rid="fig5">Figure 5</xref></label><caption><title> Minimum energy structure of 2-Phenylpropanoic acid (2-PPA)</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/1-1710047x30.png"/></fig><table-wrap id="table9" ><label><xref ref-type="table" rid="table9">Table 9</xref></label><caption><title> Spectral parameters, Einstein probabilities (A<sub>if</sub> and B<sub>if</sub>), dipole strength (D<sub>if</sub>), oscillator strength (F<sub>if</sub>), lifetime (τ) and extinction coefficient (ε<sub>max</sub>) of the electronic transition bands of 2-Phenylpropanoic acid (2-PPA) in different solvents</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Solvent</th><th align="center" valign="middle" >λ<sub>max</sub> nm</th><th align="center" valign="middle" >A<sub>if</sub> &#215; 10<sup>−7</sup> S<sup>−</sup><sup>1</sup></th><th align="center" valign="middle" >B<sub>if</sub> &#215; 10<sup>−7</sup> S・g<sup>−</sup><sup>1</sup></th><th align="center" valign="middle" >D<sub>if</sub> &#215; 10<sup>18</sup></th><th align="center" valign="middle" >F<sub>f</sub> &#215; 10<sup>2</sup></th><th align="center" valign="middle" >ε<sub>max</sub> (mole・L<sup>−1</sup>・cm<sup>−1</sup>)</th><th align="center" valign="middle" >τ ns</th></tr></thead><tr><td align="center" valign="middle"  rowspan="2"  >Ethanol</td><td align="center" valign="middle" >228.23</td><td align="center" valign="middle" >2.16</td><td align="center" valign="middle" >5.16</td><td align="center" valign="middle" >3.56</td><td align="center" valign="middle" >1.69</td><td align="center" valign="middle" >728.83</td><td align="center" valign="middle" >46.37</td></tr><tr><td align="center" valign="middle" >256.93</td><td align="center" valign="middle" >0.354</td><td align="center" valign="middle" >1.21</td><td align="center" valign="middle" >0.834</td><td align="center" valign="middle" >0.352</td><td align="center" valign="middle" >181.25</td><td align="center" valign="middle" >282.46</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Methanol</td><td align="center" valign="middle" >227.71</td><td align="center" valign="middle" >1.70</td><td align="center" valign="middle" >4.03</td><td align="center" valign="middle" >2.78</td><td align="center" valign="middle" >1.32</td><td align="center" valign="middle" >675.83</td><td align="center" valign="middle" >58.97</td></tr><tr><td align="center" valign="middle" >256.93</td><td align="center" valign="middle" >0.316</td><td align="center" valign="middle" >1.08</td><td align="center" valign="middle" >0.744</td><td align="center" valign="middle" >0.31.4</td><td align="center" valign="middle" >161.75</td><td align="center" valign="middle" >316.46</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Isopropanol</td><td align="center" valign="middle" >228.55</td><td align="center" valign="middle" >1.71</td><td align="center" valign="middle" >4.11</td><td align="center" valign="middle" >2.84</td><td align="center" valign="middle" >1.35</td><td align="center" valign="middle" >728.01</td><td align="center" valign="middle" >58.39</td></tr><tr><td align="center" valign="middle" >256.98</td><td align="center" valign="middle" >0.316</td><td align="center" valign="middle" >1.08</td><td align="center" valign="middle" >0.442</td><td align="center" valign="middle" >0.314</td><td align="center" valign="middle" >167.77</td><td align="center" valign="middle" >316.46</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Cyclohexane</td><td align="center" valign="middle" >229.40</td><td align="center" valign="middle" >1.42</td><td align="center" valign="middle" >3.46</td><td align="center" valign="middle" >2.38</td><td align="center" valign="middle" >1.13</td><td align="center" valign="middle" >682.04</td><td align="center" valign="middle" >70.24</td></tr><tr><td align="center" valign="middle" >256.76</td><td align="center" valign="middle" >0.354</td><td align="center" valign="middle" >1.21</td><td align="center" valign="middle" >0.832</td><td align="center" valign="middle" >0.352</td><td align="center" valign="middle" >183.75</td><td align="center" valign="middle" >282.46</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Bidistilled water</td><td align="center" valign="middle" >227.71</td><td align="center" valign="middle" >1.95</td><td align="center" valign="middle" >4.63</td><td align="center" valign="middle" >3.19</td><td align="center" valign="middle" >1.52</td><td align="center" valign="middle" >708.69</td><td align="center" valign="middle" >51.24</td></tr><tr><td align="center" valign="middle" >257.24</td><td align="center" valign="middle" >0.363</td><td align="center" valign="middle" >1.24</td><td align="center" valign="middle" >0.856</td><td align="center" valign="middle" >0.361</td><td align="center" valign="middle" >201.10</td><td align="center" valign="middle" >275.48</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Mineral water</td><td align="center" valign="middle" >227.19</td><td align="center" valign="middle" >1.93</td><td align="center" valign="middle" >4.56</td><td align="center" valign="middle" >3.15</td><td align="center" valign="middle" >1.50</td><td align="center" valign="middle" >714.14</td><td align="center" valign="middle" >51.69</td></tr><tr><td align="center" valign="middle" >257.11</td><td align="center" valign="middle" >0.37 3</td><td align="center" valign="middle" >1.27</td><td align="center" valign="middle" >0.879</td><td align="center" valign="middle" >0.0371</td><td align="center" valign="middle" >198.51</td><td align="center" valign="middle" >268.10</td></tr><tr><td align="center" valign="middle" >Chloroform</td><td align="center" valign="middle" >258.23</td><td align="center" valign="middle" >0.397</td><td align="center" valign="middle" >1.37</td><td align="center" valign="middle" >94.7</td><td align="center" valign="middle" >0.0398</td><td align="center" valign="middle" >186.17</td><td align="center" valign="middle" >251.89</td></tr></tbody></table></table-wrap><table-wrap id="table10" ><label><xref ref-type="table" rid="table1">Table 1</xref>0</label><caption><title> Singlet transition energies of 2-Phenylpropanoic acid in gaseous state</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Excited State Singlet-A</th><th align="center" valign="middle" >Eigenvectors</th><th align="center" valign="middle" >Transition</th><th align="center" valign="middle" >ΔE eV</th><th align="center" valign="middle" >λ<sub>calc.</sub> nm</th><th align="center" valign="middle" >F</th><th align="center" valign="middle" >λ<sub>exp.</sub> nm</th></tr></thead><tr><td align="center" valign="middle"  colspan="7"  >Excited State 1</td></tr><tr><td align="center" valign="middle" >38 → 41 38 → 44 40 → 41 40 → 42 40 → 44</td><td align="center" valign="middle" >0.38938 0.15307 0.49968 0.12154 0.13478</td><td align="center" valign="middle" >ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+4</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+2</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+4</sub></td><td align="center" valign="middle" >5.0799</td><td align="center" valign="middle" >244</td><td align="center" valign="middle" >0.0310</td><td align="center" valign="middle" >257</td></tr><tr><td align="center" valign="middle"  colspan="7"  >Excited State 2</td></tr><tr><td align="center" valign="middle" >38 → 41 39 → 41 39 → 42 39 → 44 40 → 42 40 → 43 40 → 44</td><td align="center" valign="middle" >0.14958 0.49872 −0.12444 −0.13935 −0.35902 −0.23889 0.10196</td><td align="center" valign="middle" >ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+2</sub> ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+4</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+2</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+3</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+4</sub></td><td align="center" valign="middle" >5.3127</td><td align="center" valign="middle" >233</td><td align="center" valign="middle" >0.0010</td><td align="center" valign="middle" >228</td></tr><tr><td align="center" valign="middle"  colspan="7"  >Excited State 3</td></tr><tr><td align="center" valign="middle" >38 → 41 38 → 44 39 → 41 40 → 41</td><td align="center" valign="middle" >0.46682 0.15992 −0.15381 −0.41663</td><td align="center" valign="middle" >ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+4</sub> ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+1</sub></td><td align="center" valign="middle" >5.6450</td><td align="center" valign="middle" >220</td><td align="center" valign="middle" >0.0391</td><td align="center" valign="middle" ></td></tr></tbody></table></table-wrap><table-wrap id="table11" ><label><xref ref-type="table" rid="table1">Table 1</xref>1</label><caption><title> Spectral parameters, Einstein probabilities (A<sub>if</sub> and B<sub>if</sub>), dipole strength (D<sub>if</sub>),oscillator strength (F<sub>if</sub>), lifetime (τ) and extinction coefficient (ε<sub>max</sub>) of the electronic transition bands of 3-Phenylpropanoic acid (3-PPA) in different solvents</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Solvent</th><th align="center" valign="middle" >λ<sub>max</sub> nm</th><th align="center" valign="middle" >A<sub>if</sub> &#215; 10<sup>−</sup><sup>5</sup> S<sup>−</sup><sup>1</sup></th><th align="center" valign="middle" >B<sub>if</sub> &#215; 10<sup>−</sup><sup>6</sup> S・g<sup>−</sup><sup>1</sup></th><th align="center" valign="middle" >D<sub>if</sub> &#215; 10<sup>20</sup></th><th align="center" valign="middle" >F &#215; 10<sup>4</sup></th><th align="center" valign="middle" >ε<sub>max</sub> (mole・L<sup>−1</sup>・cm<sup>−1</sup>)</th><th align="center" valign="middle" >Τ ns<sup> </sup></th></tr></thead><tr><td align="center" valign="middle"  rowspan="2"  >Ethanol</td><td align="center" valign="middle" >215.66</td><td align="center" valign="middle" >10.7</td><td align="center" valign="middle" >2.17</td><td align="center" valign="middle" >14.9</td><td align="center" valign="middle" >4.52</td><td align="center" valign="middle" >45.18</td><td align="center" valign="middle" >930.65</td></tr><tr><td align="center" valign="middle" >259.03</td><td align="center" valign="middle" >2.82</td><td align="center" valign="middle" >0.985</td><td align="center" valign="middle" >6.79</td><td align="center" valign="middle" >2.85</td><td align="center" valign="middle" >17.43</td><td align="center" valign="middle" >3549.21</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Methanol</td><td align="center" valign="middle" >215.66</td><td align="center" valign="middle" >13.5</td><td align="center" valign="middle" >2.72</td><td align="center" valign="middle" >18.8</td><td align="center" valign="middle" >9.45</td><td align="center" valign="middle" >43.92</td><td align="center" valign="middle" >740.85</td></tr><tr><td align="center" valign="middle" >259.05</td><td align="center" valign="middle" >2.93</td><td align="center" valign="middle" >1.02</td><td align="center" valign="middle" >7.06</td><td align="center" valign="middle" >2.96</td><td align="center" valign="middle" >17.72</td><td align="center" valign="middle" >3414.77</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Isopropanol</td><td align="center" valign="middle" >215.10</td><td align="center" valign="middle" >12.9</td><td align="center" valign="middle" >2.58</td><td align="center" valign="middle" >17.8</td><td align="center" valign="middle" >8.98</td><td align="center" valign="middle" >45.14</td><td align="center" valign="middle" >775.76</td></tr><tr><td align="center" valign="middle" >258.90</td><td align="center" valign="middle" >2.67</td><td align="center" valign="middle" >0.933</td><td align="center" valign="middle" >6.44</td><td align="center" valign="middle" >2.70</td><td align="center" valign="middle" >15.87</td><td align="center" valign="middle" >3739.84</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Cyclohexane</td><td align="center" valign="middle" >219.94</td><td align="center" valign="middle" >35.5</td><td align="center" valign="middle" >0.760</td><td align="center" valign="middle" >5.24</td><td align="center" valign="middle" >2.59</td><td align="center" valign="middle" >25.37</td><td align="center" valign="middle" >2814.22</td></tr><tr><td align="center" valign="middle" >259.25</td><td align="center" valign="middle" >2.23</td><td align="center" valign="middle" >0.781</td><td align="center" valign="middle" >5.39</td><td align="center" valign="middle" >2.26</td><td align="center" valign="middle" >13.92</td><td align="center" valign="middle" >4486.45</td></tr><tr><td align="center" valign="middle" >Bidistilled water</td><td align="center" valign="middle" >258.25</td><td align="center" valign="middle" >3.42</td><td align="center" valign="middle" >1.19</td><td align="center" valign="middle" >8.17</td><td align="center" valign="middle" >3.44</td><td align="center" valign="middle" >19.97</td><td align="center" valign="middle" >2922.26</td></tr><tr><td align="center" valign="middle" >Mineral water</td><td align="center" valign="middle" >258.47</td><td align="center" valign="middle" >2.86</td><td align="center" valign="middle" >0.994</td><td align="center" valign="middle" >6.85</td><td align="center" valign="middle" >2.88</td><td align="center" valign="middle" >17.99</td><td align="center" valign="middle" >3493.48</td></tr><tr><td align="center" valign="middle" >Chloroform</td><td align="center" valign="middle" >260.09</td><td align="center" valign="middle" >3.24</td><td align="center" valign="middle" >1.15</td><td align="center" valign="middle" >7.91</td><td align="center" valign="middle" >3.30</td><td align="center" valign="middle" >20.06</td><td align="center" valign="middle" >3086.17</td></tr></tbody></table></table-wrap><p><xref ref-type="table" rid="table1">Table 1</xref>1. The first excited state of the minimum energy structure of 3-PPA, <xref ref-type="fig" rid="fig6">Figure 6</xref>, includes the transitions ψ<sub>m</sub><sub>−2</sub>→ψ<sub>m</sub><sub>+1</sub>, ψ<sub>m</sub><sub>−2</sub>-→ψ<sub>m</sub><sub>+2</sub> and ψ<sub>m</sub><sub>−2</sub>→ψ<sub>m</sub><sub>+4</sub>, <xref ref-type="table" rid="table1">Table 1</xref>2. The major transition in the first excited state is coming mainly from the transition ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+1</sub>, with eigenvector 0.65683. The calculated transition energy between the ground state to the second excited state lies at 234 nm which is not far from the experimental band position 215 nm in the spectra of 3-PPA, <xref ref-type="fig" rid="fig7">Figure 7</xref>. The major transition in the second and third excited states include mainly the transition from ψ<sub>m</sub> to ψ<sub>m</sub><sub>+1</sub> with eigenvectors 0.50780 and 0.46741 respectively. From comparison point of view of the spectral parameters, <xref ref-type="table" rid="table8">Table 8</xref>, <xref ref-type="table" rid="table9">Table 9</xref>, <xref ref-type="table" rid="table1">Table 1</xref>1 between IBF and propanioc acid derivatives (2-PPA and 3-PPA), it can be noticed that the spectral parameters of IBF and 2-PPA namely Einstein transition probabilities (A<sub>if</sub> and B<sub>if</sub>) are close to each other but the dipole strengths D<sub>if</sub>, oscillator strengths, f<sub>if</sub> and extinction coefficients ε<sub>max</sub>, of IBF are higher than those of 2-PPA but the life times of excitation τ, of 2-PPA are higher than those of IBF. From comparison general point of view, the spectral parameters of IBF and 2-PPA are higher than those of 3-PPA except the excitation life times of 3-PPA which are much higher than those of IBF and 2-PPA.</p><p>The blue or green colors (aquamarine) of the copper complexes as in the Cu(ligand)<sub>2</sub> complex are due to the of absorption band in the region 600 - 900 nm in the spectra. For Cu(IBF)<sub>2</sub> complex spectra, <xref ref-type="fig" rid="fig8">Figure 8</xref>, it has an absorption band at about λ<sub>max</sub> = 700 nm which is attributed to d → d transition [<xref ref-type="bibr" rid="scirp.66069-ref15">15</xref>] . From <xref ref-type="table" rid="table1">Table 1</xref>3, the d → d transition band of copper ion has high life time of excitation more than 2000 ns which is much higher than the excitation time of the band at about λ<sub>max</sub> = 280 nm, <xref ref-type="fig" rid="fig8">Figure 8</xref>. The Einstein transition probabilities (A<sub>if</sub> and B<sub>if</sub>), dipole strength D<sub>if</sub>, molar absorptivities ε and oscillator strength F<sub>if</sub> have much higher values at the absorption band at about λ<sub>max</sub> = 280 nm more than those at about λ<sub>max</sub> = 700 nm. From <xref ref-type="fig" rid="fig3">Figure 3</xref>, <xref ref-type="fig" rid="fig8">Figure 8</xref>, it has been noticed that the first excitation band of IBF at λ<sub>max</sub> = 263, has been red shifted to λ<sub>max</sub> = 280 nm in the spectra Cu(IBF)<sub>2</sub> complex due to some planarity in the complex molecule, <xref ref-type="fig" rid="fig9">Figure 9</xref>.</p><p>From <xref ref-type="table" rid="table1">Table 1</xref>4 of the spectral data of Zn-complex it can be concluded that this molecule has an absorption absorbance at the same wavelengths of IBF i.e. at λ<sub>max</sub> = 230 and λ<sub>max</sub> = 263 nm as well as in the molar absorptivities of IBF, ε<sub>max</sub>, are not far from those of Zn-complex spectral data. There is satisfied resemblance between the values of the dipole strengths, D<sub>if</sub> and life time of excitation, τ in the spectral data of IBF and the complex <xref ref-type="table" rid="table8">Table 8</xref> and <xref ref-type="table" rid="table1">Table 1</xref>4, except the oscillator strengths of IBF spectral data, <xref ref-type="table" rid="table8">Table 8</xref>, are higher than those of the Zn-complex spectral data.</p><p>From the minimum energy structure of Zn-complex, <xref ref-type="fig" rid="fig1">Figure 1</xref>0, shows that the IBF moieties in the complex are perpendicular to each other therefore the absorbance of the complex is confined in the absorption bands of IBF molecule at 228 and 263 nm, <xref ref-type="fig" rid="fig1">Figure 1</xref>1 as in the case in the spectra of IBF, <xref ref-type="fig" rid="fig3">Figure 3</xref>. This appears clearly from their appreciable resemblance between their spectral data, <xref ref-type="table" rid="table8">Table 8</xref>, <xref ref-type="table" rid="table1">Table 1</xref>4. This coincidence between the spectra of IBF and Zn-complex is coming out from the perpendicularity of the two IBF moieties in the complex therefore the conjugation overall the molecule is interrupted between the two IBF moieties in the complex.</p><fig id="fig6"  position="float"><label><xref ref-type="fig" rid="fig6">Figure 6</xref></label><caption><title> Minimum energy structure of 3-Phenylpropanoic acid (3-PPA)</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/1-1710047x31.png"/></fig><fig id="fig7"  position="float"><label><xref ref-type="fig" rid="fig7">Figure 7</xref></label><caption><title> Electronic spectra of 3-Phenylpropanoic acid (50.7 mmol・L<sup>−1</sup>) in (a) EtOH, (b) MeOH, (c) Isopropanol, (d) CHCl<sub>3</sub>, (e) Cyclohexane, (f) Bidistilled water, and (g) Mineral water</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/1-1710047x32.png"/></fig><fig id="fig8"  position="float"><label><xref ref-type="fig" rid="fig8">Figure 8</xref></label><caption><title> Electronic spectra of Cu-Ibuprofen complex (1.9 mmol・L<sup>−1</sup>) in (a) EtOH, (b) MeOH, (c) Isopropanol, (d) CHCl<sub>3</sub>, and (e) Cyclohexane</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/1-1710047x33.png"/></fig><fig id="fig9"  position="float"><label><xref ref-type="fig" rid="fig9">Figure 9</xref></label><caption><title> Minimum energy structure of Cu(IBF)<sub>2</sub> complex</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/1-1710047x34.png"/></fig><fig id="fig10"  position="float"><label><xref ref-type="fig" rid="fig1">Figure 1</xref>0</label><caption><title> Minimum energy structure of Zn(IBF)<sub>2</sub> complex, [<xref ref-type="bibr" rid="scirp.66069-ref11">11</xref>] </title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/1-1710047x35.png"/></fig><fig id="fig11"  position="float"><label><xref ref-type="fig" rid="fig1">Figure 1</xref>1</label><caption><title> Electronic spectra of Zn(IBF) 2.-2H<sub>2</sub>O complex (1.17 mmol・L<sup>−1</sup>) in (a) EtOH, (b) MeOH, (c) Isopropanol, (d) CHCl<sub>3</sub>, (e) Cyclohexane, and (f) Bidistilled water</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/1-1710047x36.png"/></fig><table-wrap id="table12" ><label><xref ref-type="table" rid="table1">Table 1</xref>2</label><caption><title> Singlet transition energies of 3-Phenylpropanoic acid</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Excited State Singlet-A</th><th align="center" valign="middle" >Eigenvectors</th><th align="center" valign="middle" >Transition</th><th align="center" valign="middle" >ΔE eV</th><th align="center" valign="middle" >λ<sub>calc.</sub> nm</th><th align="center" valign="middle" >F</th><th align="center" valign="middle" >λ<sub>exp.</sub> nm</th></tr></thead><tr><td align="center" valign="middle"  colspan="7"  >Excited State 1</td></tr><tr><td align="center" valign="middle" >38 → 41 38 → 42 38 → 44</td><td align="center" valign="middle" >0.65683 −0.16373 −0.10939</td><td align="center" valign="middle" >ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+2</sub> ψ<sub>m</sub><sub>−2</sub> → ψ<sub>m</sub><sub>+4</sub></td><td align="center" valign="middle" >5.2628</td><td align="center" valign="middle" >236</td><td align="center" valign="middle" >0.0001</td><td align="center" valign="middle" >259</td></tr><tr><td align="center" valign="middle"  colspan="7"  >Excited State 2</td></tr><tr><td align="center" valign="middle" >39 → 41 39 → 42 39 → 44 40 → 41 40 → 44</td><td align="center" valign="middle" >−0.15524 −0.31449 0.16121 0.50780 0.30508</td><td align="center" valign="middle" >ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+2</sub> ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+4</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+4</sub></td><td align="center" valign="middle" >5.3097</td><td align="center" valign="middle" >234</td><td align="center" valign="middle" >0.0107</td><td align="center" valign="middle" >215</td></tr><tr><td align="center" valign="middle"  colspan="7"  >Excited State 3</td></tr><tr><td align="center" valign="middle" >39 → 41 39 → 42 40 → 41 40 → 42 40 → 44</td><td align="center" valign="middle" >0.13112 0.24926 0.46741 −0.24198 −0.37012</td><td align="center" valign="middle" >ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub><sub>−1</sub> → ψ<sub>m</sub><sub>+2</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+1</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+2</sub> ψ<sub>m</sub> → ψ<sub>m</sub><sub>+4</sub></td><td align="center" valign="middle" >5.5265</td><td align="center" valign="middle" >224</td><td align="center" valign="middle" >0.0044</td><td align="center" valign="middle" ></td></tr></tbody></table></table-wrap><table-wrap id="table13" ><label><xref ref-type="table" rid="table1">Table 1</xref>3</label><caption><title> Spectral parameters, Einstein probabilities (A<sub>if</sub> and B<sub>if</sub>), dipole strength (D<sub>if</sub>), oscillator strength (F<sub>if</sub>), lifetime (τ) and extinction coefficient (ε<sub>max</sub>) of the electronic transition bands of Cu<sup>+2</sup> ion in Cu(IBF)<sub>2</sub> complex in different solvents</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Solvent</th><th align="center" valign="middle" >λ<sub>max</sub> nm</th><th align="center" valign="middle" >A<sub>if</sub> &#215; 10<sup>−</sup><sup>6</sup> S<sup>−</sup><sup>1</sup></th><th align="center" valign="middle" >B<sub>if</sub> &#215; 10<sup>−</sup><sup>8</sup> S・g<sup>−</sup><sup>1</sup></th><th align="center" valign="middle" >D<sub>if</sub> &#215; 10<sup>18</sup></th><th align="center" valign="middle" >f<sub>if</sub> &#215; 10<sup>3</sup></th><th align="center" valign="middle" >ε<sub>max</sub> (mole・L<sup>−1</sup>・cm<sup>−1</sup>)</th><th align="center" valign="middle" >τ ns<sup> </sup></th></tr></thead><tr><td align="center" valign="middle"  rowspan="2"  >Ethanol</td><td align="center" valign="middle" >285.98</td><td align="center" valign="middle" >157</td><td align="center" valign="middle" >7.37</td><td align="center" valign="middle" >50.8</td><td align="center" valign="middle" >193</td><td align="center" valign="middle" >2414.24</td><td align="center" valign="middle" >6.37</td></tr><tr><td align="center" valign="middle" >694.42</td><td align="center" valign="middle" >0.486</td><td align="center" valign="middle" >0.328</td><td align="center" valign="middle" >2.26</td><td align="center" valign="middle" >3.53</td><td align="center" valign="middle" >206.27</td><td align="center" valign="middle" >2057.61</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Methanol</td><td align="center" valign="middle" >275.02</td><td align="center" valign="middle" >107</td><td align="center" valign="middle" >4.48</td><td align="center" valign="middle" >30.9</td><td align="center" valign="middle" >122</td><td align="center" valign="middle" >2527.24</td><td align="center" valign="middle" >9.35</td></tr><tr><td align="center" valign="middle" >693.64</td><td align="center" valign="middle" >0.384</td><td align="center" valign="middle" >0.258</td><td align="center" valign="middle" >1.78</td><td align="center" valign="middle" >2.78</td><td align="center" valign="middle" >154.24</td><td align="center" valign="middle" >2604.17</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Isopropanol</td><td align="center" valign="middle" >291.04</td><td align="center" valign="middle" >142</td><td align="center" valign="middle" >7.04</td><td align="center" valign="middle" >48.6</td><td align="center" valign="middle" >181</td><td align="center" valign="middle" >2265.86</td><td align="center" valign="middle" >7.04</td></tr><tr><td align="center" valign="middle" >699.87</td><td align="center" valign="middle" >0.556</td><td align="center" valign="middle" >0.383</td><td align="center" valign="middle" >2.64</td><td align="center" valign="middle" >4.10</td><td align="center" valign="middle" >238.56</td><td align="center" valign="middle" >1798.56</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Chloroform</td><td align="center" valign="middle" >275.58</td><td align="center" valign="middle" >88.7</td><td align="center" valign="middle" >3.73</td><td align="center" valign="middle" >25.8</td><td align="center" valign="middle" >101</td><td align="center" valign="middle" >2305.71</td><td align="center" valign="middle" >11.27</td></tr><tr><td align="center" valign="middle" >695.78</td><td align="center" valign="middle" >0.515</td><td align="center" valign="middle" >0.349</td><td align="center" valign="middle" >2.41</td><td align="center" valign="middle" >3.76</td><td align="center" valign="middle" >214.75</td><td align="center" valign="middle" >1941.75</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Cyclohexane</td><td align="center" valign="middle" >272.74</td><td align="center" valign="middle" >127</td><td align="center" valign="middle" >5.19</td><td align="center" valign="middle" >35.8</td><td align="center" valign="middle" >143</td><td align="center" valign="middle" >2187.01</td><td align="center" valign="middle" >7.87</td></tr><tr><td align="center" valign="middle" >703.37</td><td align="center" valign="middle" >0.376</td><td align="center" valign="middle" >0.263</td><td align="center" valign="middle" >1.81</td><td align="center" valign="middle" >2.80</td><td align="center" valign="middle" >169.81</td><td align="center" valign="middle" >2659.57</td></tr></tbody></table></table-wrap><table-wrap id="table14" ><label><xref ref-type="table" rid="table1">Table 1</xref>4</label><caption><title> Spectral parameters, Einstein probabilities (A<sub>if</sub> and B<sub>if</sub>), Dipole strength (D<sub>if</sub>), Oscillator strength (F<sub>if</sub>), Lifetime (τ) and Extinction coefficient (ε<sub>max</sub>) of the electronic transition bands of Zn(IBF)<sub>2</sub>・2H<sub>2</sub>O in different solvents</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Solvent</th><th align="center" valign="middle" >λ<sub>max</sub> nm</th><th align="center" valign="middle" >A<sub>if</sub> &#215; 10<sup>−</sup><sup>7</sup> S<sup>−</sup><sup>1</sup></th><th align="center" valign="middle" >B<sub>if</sub> &#215; 10<sup>−</sup><sup>7</sup> S・g<sup>−</sup><sup>1</sup></th><th align="center" valign="middle" >D<sub>if</sub> &#215; 10<sup>18</sup></th><th align="center" valign="middle" >F<sub>f</sub> &#215; 10<sup>3</sup></th><th align="center" valign="middle" >ε<sub>max</sub> (mole・L<sup>−1</sup>・cm<sup>−1</sup>)</th><th align="center" valign="middle" >τ ns<sup> </sup></th></tr></thead><tr><td align="center" valign="middle"  rowspan="2"  >Ethanol</td><td align="center" valign="middle" >227.67</td><td align="center" valign="middle" >2.17</td><td align="center" valign="middle" >5.16</td><td align="center" valign="middle" >3.56</td><td align="center" valign="middle" >0.170</td><td align="center" valign="middle" >2325.29</td><td align="center" valign="middle" >46.08</td></tr><tr><td align="center" valign="middle" >263.60</td><td align="center" valign="middle" >0.528</td><td align="center" valign="middle" >1.95</td><td align="center" valign="middle" >1.34</td><td align="center" valign="middle" >5.53</td><td align="center" valign="middle" >281.74</td><td align="center" valign="middle" >189.39</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Methanol</td><td align="center" valign="middle" >227.99</td><td align="center" valign="middle" >2.95</td><td align="center" valign="middle" >7.03</td><td align="center" valign="middle" >4.85</td><td align="center" valign="middle" >0.231</td><td align="center" valign="middle" >2372.86</td><td align="center" valign="middle" >33.90</td></tr><tr><td align="center" valign="middle" >263.90</td><td align="center" valign="middle" >0.542</td><td align="center" valign="middle" >2.00</td><td align="center" valign="middle" >1.38</td><td align="center" valign="middle" >5.68</td><td align="center" valign="middle" >313.70</td><td align="center" valign="middle" >184.50</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Isopropanol</td><td align="center" valign="middle" >230.07</td><td align="center" valign="middle" >2.17</td><td align="center" valign="middle" >5.32</td><td align="center" valign="middle" >3.67</td><td align="center" valign="middle" >0.173</td><td align="center" valign="middle" >1592.12</td><td align="center" valign="middle" >46.08</td></tr><tr><td align="center" valign="middle" >263.21</td><td align="center" valign="middle" >0.509</td><td align="center" valign="middle" >1.87</td><td align="center" valign="middle" >1.29</td><td align="center" valign="middle" >5.31</td><td align="center" valign="middle" >288.61</td><td align="center" valign="middle" >196.46</td></tr><tr><td align="center" valign="middle" >Chloroform</td><td align="center" valign="middle" >262.82</td><td align="center" valign="middle" >0.522</td><td align="center" valign="middle" >1.91</td><td align="center" valign="middle" >1.32</td><td align="center" valign="middle" >5.43</td><td align="center" valign="middle" >311.87</td><td align="center" valign="middle" >191.57</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Cyclohexane</td><td align="center" valign="middle" >228.94</td><td align="center" valign="middle" >4.95</td><td align="center" valign="middle" >11.9</td><td align="center" valign="middle" >8.23</td><td align="center" valign="middle" >0.390</td><td align="center" valign="middle" >2505.71</td><td align="center" valign="middle" >20.20</td></tr><tr><td align="center" valign="middle" >262.95</td><td align="center" valign="middle" >0.911</td><td align="center" valign="middle" >3.33</td><td align="center" valign="middle" >2.30</td><td align="center" valign="middle" >9.49</td><td align="center" valign="middle" >421.21</td><td align="center" valign="middle" >109.77</td></tr><tr><td align="center" valign="middle"  rowspan="2"  >Bidistilled water</td><td align="center" valign="middle" >229.20</td><td align="center" valign="middle" >5.44</td><td align="center" valign="middle" >13.2</td><td align="center" valign="middle" >9.08</td><td align="center" valign="middle" >0.430</td><td align="center" valign="middle" >2547.47</td><td align="center" valign="middle" >18.38</td></tr><tr><td align="center" valign="middle" >262.64</td><td align="center" valign="middle" >0.587</td><td align="center" valign="middle" >2.16</td><td align="center" valign="middle" >1.49</td><td align="center" valign="middle" >6.14</td><td align="center" valign="middle" >352.47</td><td align="center" valign="middle" >170.36</td></tr></tbody></table></table-wrap></sec><sec id="s4_2"><title>4.2. Anticancer Effect of Ibuprofen Drug</title><p>To deepen the denotation of cancer, it is mutual electron transfer between the nucleic acid bases and electron donor or electron acceptor, i.e. free radicals, drugs even some food like grills and fries. Losing an electron from the nucleic acid bases inside the nucleus produces carcinogenic cell in which the nucleus acts as electron donor to any electron acceptor such as in case of Paracetamol metabolite in the liver, NABQI, <xref ref-type="fig" rid="fig1">Figure 1</xref>2 having high electron affinity being sufficient to withdraw an electron from guanine in the nucleus of liver cell in absence of glutathione [<xref ref-type="bibr" rid="scirp.66069-ref12">12</xref>] . Therefore the nucleus looses an electron producing cationic nucleus as a free radical which can behave as positive carcinogenic cell. The positive cancer means that the nucleus lacks an electron due to the mutual electron transfer; therefore it behaves abnormally i.e. cancer. This type of cancer can be treated by drugs having spontaneous electron donor character in a certain condition to compensate the electron deficiency from the nucleus such as Ibuprofen drug in its anionic forms.</p><p>After administration of Ibuprofen drug, it passes via human stomach of pH ~ 2 and in full stomach of pH ~ 4 - 5 saving the molecular form of the drug AH. After the drug arrival to gastrointestine of pH ~8 - 9, therefore the anionic form A<sup>−</sup> of Ibuprofen drug exists side by side with the molecular form AH in intestine. The ionization constant of Ibuprofen dsrug pK<sub>a</sub> = s4.85, using the relation:</p><disp-formula id="scirp.66069-formula43"><graphic  xlink:href="http://html.scirp.org/file/1-1710047x37.png"  xlink:type="simple"/></disp-formula><p>Therefore the ratio between anions A<sup>−</sup> and molecules AH being equal to 1 approximately. The pH value of human blood equals to 7.4 and its pK<sub>a</sub> = 5.2, hence the ratio between anions A<sup>−</sup> and molecules AH is still nearly equal to 1. Therefore Ibuprofen drug exists in the intestine and in the blood as the anionic form A<sup>−</sup> and the molecular form AH. The existence of free molecule of the drug AH together with the anion A<sup>−</sup> in the intestine establishes equilibrium between them. This mixture is spontaneous electron donor to the carcinogenic cells rendering them being in normal state.</p><disp-formula id="scirp.66069-formula44"><graphic  xlink:href="http://html.scirp.org/file/1-1710047x38.png"  xlink:type="simple"/></disp-formula><p>The ionization energy, Ip, of Ibuprofen drug molecule by DFT method in the stomach being equal to, 6.6804 eV, and decreases when the drug arrives to the small intestine at which the pH value lies between 8 - 9 and the value of the ionization potential decreases to 0.9015 eV, table. Therefore the Ibuprofen drug behaves as spontaneous electron donor in the small intestine. In the same way, the electron affinity of Ibuprofen drug molecule in the stomach is equal to 0.81634 eV, table, which decreases in the small intestine to be −1.4392 eV. This means that Ibuprofen drug anion hasn’t the ability to receive an electron from the IBF molecules. Spontaneous electron donor to nucleic acid bases must fulfill the following condition:</p><fig id="fig12"  position="float"><label><xref ref-type="fig" rid="fig1">Figure 1</xref>2</label><caption><title> Three path ways of Paracetamol metabolism</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/1-1710047x39.png"/></fig><disp-formula id="scirp.66069-formula45"><graphic  xlink:href="http://html.scirp.org/file/1-1710047x40.png"  xlink:type="simple"/></disp-formula><p>where Ip is the ionization potential energy of the anion and Ea(NAB) is the electron affinity of nucleic acid bases.</p><p>From comparison point of view with respect to the nucleic acid bases it has been found the following values of the electronic total energy, ionization energy and electron affinity in the following <xref ref-type="table" rid="table1">Table 1</xref>6.</p><p>From <xref ref-type="table" rid="table1">Table 1</xref>5, it has been found that guanine has the lowest Ip, 6.1879 among all the other nucleic acid bases hence it acts as an electron donor forming the cationic nucleus of the carcinogenic cell.</p><p>Since Ibuprofen in the small intestine has very low ionization energy, 0.9015 eV and the electron affinity values of nucleic acid bases are higher than that of IBF anion; therefore IBF anions in the presence of IBF molecules can act as spontaneous electron donor to compensate the electron deficiency of the carcinogenic cells in the intestine. The presence of the mixture of A<sup>−</sup> and AH in the blood gives the chance to inhibit different types of cancers such as protostate, lung and breast cancers [<xref ref-type="bibr" rid="scirp.66069-ref2">2</xref>] - [<xref ref-type="bibr" rid="scirp.66069-ref4">4</xref>] .</p><p>From the previous <xref ref-type="table" rid="table1">Table 1</xref>6, it can be concluded that the anions of (2PPA) and (3-PPA) have Ip values which are lower than that of the anion of IBF therefore these two compounds can act as spontaneous electron donor and can be used as stronger anticancer more than IBF drug. The heat contents (ΔH) of alteration of AH molecule to its A<sup>− </sup>anion for the studied compounds (IBF, 2-PPA and 3-PPA) have the following values respectively, 352.393, 347.619 and 349.504 k・scal・mol<sup>−1</sup> at 37˚C. Therefore this mixture of molecules and anions of the studied compounds are anticancer [<xref ref-type="bibr" rid="scirp.66069-ref2">2</xref>] - [<xref ref-type="bibr" rid="scirp.66069-ref4">4</xref>] .</p></sec><sec id="s4_3"><title>4.3. Metabolism of IBF Drug</title><p>The metabolic activation may be via chiral inversion not only leads to higher therapeutic potency; from another hand it may also cause a great risk of acute kidney failure in patients with renal disorder. The side effect of Ibuprofen includes gastrointestinal disturbance and central nervous system (CNS) depression. All of these adverse effects are found to be mild, [<xref ref-type="bibr" rid="scirp.66069-ref16">16</xref>] . After arrival of ibuprofen to the blood after absorption from the small intestine to follow up via blood of pH 7.4 toward liver where its metabolism takes place to give ibuprofen acylglucuronide, [<xref ref-type="bibr" rid="scirp.66069-ref16">16</xref>] [<xref ref-type="bibr" rid="scirp.66069-ref17">17</xref>] , oxidation to produce two major metabolites, 2-hydroxyibuprofen (2HIBF) and carboxy-ibupro- fen (CIBF), <xref ref-type="fig" rid="fig1">Figure 1</xref>3. The other minor oxidation products are: 1-hydroxyibuprofen (1HIBF), 3-hydroxyibu- profen (3HIBF) and 2-(4-carboxyphenyl) propanoic acid (CPPA) were detected in the human urine. CYP2C9 is the predominant enzyme which is responsible for the oxidation metabolism of Ibuprofen (IBF). The DFT Parameters including total electronic energy (TE), ionization potential (Ip) and electron affinity (Ea) of the metabolite products are given in the following <xref ref-type="table" rid="table1">Table 1</xref>7.</p><table-wrap id="table15" ><label><xref ref-type="table" rid="table1">Table 1</xref>5</label><caption><title> DFT/6-31G**Parameters of nucleic acid bases (N.A.B.) and IBF drug</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Compound</th><th align="center" valign="middle" >TE au</th><th align="center" valign="middle" >Ip eV</th><th align="center" valign="middle" >Ea eV</th></tr></thead><tr><td align="center" valign="middle" >Adenine</td><td align="center" valign="middle" >−467.17488</td><td align="center" valign="middle" >6.4061</td><td align="center" valign="middle" >+1.2672</td></tr><tr><td align="center" valign="middle" >Guanine</td><td align="center" valign="middle" >−542.37704</td><td align="center" valign="middle" >6.1879</td><td align="center" valign="middle" >+1.2828</td></tr><tr><td align="center" valign="middle" >Cytosine</td><td align="center" valign="middle" >−394.82291</td><td align="center" valign="middle" >6.5819</td><td align="center" valign="middle" >+1.4768</td></tr><tr><td align="center" valign="middle" >Uracil</td><td align="center" valign="middle" >−414.70313</td><td align="center" valign="middle" >7.3316</td><td align="center" valign="middle" >+1.8626</td></tr><tr><td align="center" valign="middle" >S-Ibuprofen in the Stomach</td><td align="center" valign="middle" >−656.5408</td><td align="center" valign="middle" >6.6837</td><td align="center" valign="middle" >+0.8879</td></tr><tr><td align="center" valign="middle" >S-Ibuprofen in the small intestine</td><td align="center" valign="middle" >−655.9788</td><td align="center" valign="middle" >0.9015</td><td align="center" valign="middle" >−1.4392</td></tr></tbody></table></table-wrap><p>TE is the total energy, Ip is the ionization energy, Ea is the electron affinity.</p><table-wrap id="table16" ><label><xref ref-type="table" rid="table1">Table 1</xref>6</label><caption><title> Anions DFT-parameters of IBF Drug and some analogues</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Anion</th><th align="center" valign="middle" >TE au</th><th align="center" valign="middle" >Ip eV</th><th align="center" valign="middle" >Ea eV</th><th align="center" valign="middle" >Dip. Mom. D</th></tr></thead><tr><td align="center" valign="middle" >IBF</td><td align="center" valign="middle" >−655.9788</td><td align="center" valign="middle" >0.9015</td><td align="center" valign="middle" >−1.4392</td><td align="center" valign="middle" >17.4635</td></tr><tr><td align="center" valign="middle" >2-PPA</td><td align="center" valign="middle" >−498.7676</td><td align="center" valign="middle" >0.8966</td><td align="center" valign="middle" >−2.0580</td><td align="center" valign="middle" >10.6771</td></tr><tr><td align="center" valign="middle" >3-PPA</td><td align="center" valign="middle" >−498.7635</td><td align="center" valign="middle" >0.6289</td><td align="center" valign="middle" >−1.7385</td><td align="center" valign="middle" >15.5631</td></tr></tbody></table></table-wrap><fig id="fig13"  position="float"><label><xref ref-type="fig" rid="fig1">Figure 1</xref>3</label><caption><title> Metabolic pathways for ibuprofen, [<xref ref-type="bibr" rid="scirp.66069-ref16">16</xref>] [<xref ref-type="bibr" rid="scirp.66069-ref17">17</xref>] ―HPPA has not been detected</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/1-1710047x41.png"/></fig><table-wrap id="table17" ><label><xref ref-type="table" rid="table1">Table 1</xref>7</label><caption><title> Anions DFT-parameters of IBF drug and some analogues</title></caption><table><tbody><thead><tr><th align="center" valign="middle" >Compound</th><th align="center" valign="middle"  colspan="2"  >TE</th><th align="center" valign="middle"  colspan="2"  >Ip</th><th align="center" valign="middle" >Ea</th></tr></thead><tr><td align="center" valign="middle" >S-IBF</td><td align="center" valign="middle"  colspan="2"  >−656.54088</td><td align="center" valign="middle"  colspan="2"  >6.6804</td><td align="center" valign="middle" >0.8163</td></tr><tr><td align="center" valign="middle" >1HIBF</td><td align="center" valign="middle"  colspan="2"  >−731.73070</td><td align="center" valign="middle"  colspan="2"  >6.8831</td><td align="center" valign="middle" >1.0591</td></tr><tr><td align="center" valign="middle" >2HIBF</td><td align="center" valign="middle"  colspan="2"  >−731.73523</td><td align="center" valign="middle"  colspan="2"  >6.5980</td><td align="center" valign="middle" >0.8376</td></tr><tr><td align="center" valign="middle" >3HIBF</td><td align="center" valign="middle"  colspan="2"  >−731.72320</td><td align="center" valign="middle"  colspan="2"  >6.8916</td><td align="center" valign="middle" >1.0803</td></tr><tr><td align="center" valign="middle" >CIBF</td><td align="center" valign="middle"  colspan="2"  >−805.74479</td><td align="center" valign="middle"  colspan="2"  >6.8097</td><td align="center" valign="middle" >1.0071</td></tr><tr><td align="center" valign="middle"  colspan="2"  >CPPA</td><td align="center" valign="middle" >−687.83361</td><td align="center" valign="middle" >7.5253</td><td align="center" valign="middle"  colspan="2"  >2.0444</td></tr><tr><td align="center" valign="middle" ></td><td align="center" valign="middle" ></td><td align="center" valign="middle" ></td><td align="center" valign="middle" ></td><td align="center" valign="middle" ></td><td align="center" valign="middle" ></td></tr></tbody></table></table-wrap><p>From comparative point of view, the Ip’s and Ea’s of the metabolite products of IBF, <xref ref-type="table" rid="table1">Table 1</xref>7, <xref ref-type="fig" rid="fig1">Figure 1</xref>4, with those of nucleic acid bases, <xref ref-type="table" rid="table1">Table 1</xref>5 using the same method of calculations, it can be concluded that all the values of Ip’s and Ea’s of the IBF metabolite products are consistent with those of the nucleic acid bases. Therefore there isn’t possibility of electron transfer between them and the acidic metabolites tend to have some anionic forms in the slightly basic medium in the human blood, 7.4, hence, the metabolite products of IBF are safe from cancer effect in the liver or in the kidney.</p><p>From the different values of Ip’s of nucleic acid bases, <xref ref-type="table" rid="table1">Table 1</xref>5, it has been found that guanine has the lowest Ip value among all the other nucleic acid bases, 6.1879 eV and with respect to that of 1HIBF metabolite, 6.8831 eV. The metabolite 1HIBF has an electron affinity being equal to 1.0591 eV. Therefore guanine acts as electron donor with respect to 1HIBF metabolite and the electron transfer energy between them reaches to 3.841 eV which is corresponding to a wavelength being equal to 322 nm. The electron affinity of uracil, 1.8626 eV, <xref ref-type="table" rid="table1">Table 1</xref>5, is higher than that of 2HIBF, 0.8376 eV, and the ionization energy of uracil, 7.3316 eV is higher than that of 2HIBF, 6.598 eV therefore uracil acts as electron acceptor with respect to 2HIBF metabolite to produce the negative cancer of the anionic nucleus. Therefore the electron transfer energy barrier, 4.734 eV (262 nm)</p><fig id="fig14"  position="float"><label><xref ref-type="fig" rid="fig1">Figure 1</xref>4</label><caption><title> The minimum energy structures of IBF metabolites in the human body</title></caption><graphic mimetype="image"   position="float"  xlink:type="simple"  xlink:href="http://html.scirp.org/file/1-1710047x42.png"/></fig><p>prevents the electron transfer between them [<xref ref-type="bibr" rid="scirp.66069-ref12">12</xref>] [<xref ref-type="bibr" rid="scirp.66069-ref18">18</xref>] [<xref ref-type="bibr" rid="scirp.66069-ref19">19</xref>] leading to the absence of the cancer disease in the liver. From general point of view, guanine due to its lowest Ip and low Ea, acts as electron donor producing positive cancer and uracil due to its high Ea and high Ip, acts as an electron acceptor producing negative cancer. Generally, the anion of 3-PPA is more electron donor than that of IBF in <xref ref-type="table" rid="table1">Table 1</xref>6, since 3-PPA anion has the lowest ionization energy. Therefore it is advisable to use this compound instead of IBF as a drug to inhibit positive cancer diseases.</p></sec></sec><sec id="s5"><title>5. Conclusions</title><p>1) It is good for the health to take Ibuprofen drug regularly to avoid cancers of gastrointestine, protostate, breast and lung.</p><p>2) 2PPA and 3-PPA are better as anticancer than Ibuprofen drug.</p><p>3) Ibuprofen metal ion complexes are not anti-cancers like anions of IBF, 2-PPA and 3-PPa.</p></sec><sec id="s6"><title>Cite this paper</title><p>Anwar El- Shahawy,Hana Gashlan,Safaa Qusti,Ghada Ezzat,Hossam Emara, (2016) DFT-Quantum Spectroscopic Studies and Anti-Cancer Effect of Ibuprofen Drug and Some Analogues. 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