TITLE:
Synthesis, Electrochemistry and Antitumor Activity of 1’H, 3’H(Me)-spiro-[(aza)benzimidazoline-2’, 3-(1,2-diferrocenylcyclopropenes)], 2-(1,2-Diferrocenylvinyl)benz- and Azabenzimidazoles
AUTHORS:
Jessica J. Sánchez García, Luis Ortiz-Frade, Elena Martínez-Klimova, Juan C. García Ramos, Marcos Flores-Alamo, Teresa Ramírez Apan, Elena I. Klimova
KEYWORDS:
Diferrocenyl(methylthio)cyclopropenylium, 2-(1, 2-Diferrocenylvinyl)(aza)benzimidazoles, 1’H, 3’H(Me)-spiro-[(aza)benzimidazoline-2’, 3-(1, 2-diferrocenylcyclopropenes)], Electrochemistry, Antitumor Activity
JOURNAL NAME:
Open Journal of Synthesis Theory and Applications,
Vol.3 No.4,
October
22,
2014
ABSTRACT: A new
method of synthesis of 2-(1,2-diferrocenylvinyl)benz- and azabenzimidazoles
(3a-f), (4a-f) and 1’H,3’H(Me)-spiro-[(aza)benzimidazoline-2’,3-(1,2-diferrocenylcyclopropenes)]
(5a-f) via reactions of diferrocenyl(methylsulfanyl)cyclopropenylium
iodide (1) with aromatic o-diamines
(2a-f) in the presence of Et3N (80°C - 82°C) is described. The
structures of the resultant compounds are established using IR, 1H
and 13C NMR spectroscopy, mass spectrometry and elemental analysis.
The structure of one compound, cis-2-(1,2-diferrocenylvinyl)-1-methylbenzimidazole
(3b), is confirmed by X-ray diffraction analysis. The electrochemical
properties of compounds 3a, 3b, 3d and 5f are investigated using cyclic square wave
voltammetry. Two electrochemical processes (I-II), attributed to oxidation of
the ferrocene moieties, and the values of E0’(I), E0’(II), DE0’(II-I) and comporportionation constant Kcom are reported. The bioactivities of seven compounds 3a,
3c-f, 5d, 5f are evaluated. Compound 5f is the most active compound with a
modest cytotoxic activity against six human cancer cell lines: U-251 (glioma),
PC-3 (prostate cancer), K-562 (leukemia), HCT-15 (colon cancer), MCF-7 (breast
cancer) and SKLU-1 (lung cancer).