TITLE:
A Slightly Modified Expression of the Polar Surface Area Applied to an Olfactory Study
AUTHORS:
Paul Laffort
KEYWORDS:
Polar Surface Area; QSAR; Cheminformatics; Olfaction; Honey-Bee; Psychophysics
JOURNAL NAME:
Open Journal of Physical Chemistry,
Vol.3 No.4,
October
28,
2013
ABSTRACT: The
polar surface area of a molecule is currently defined as the surface sum over
all polar atoms, primarily oxygen and nitrogen, also including their attached
hydrogens (named PSA1 in the
present study). Some authors also include sulfur and phosphor (PSA3). The
slight modification suggested here is based on the fact that it is difficult to
consider, on a theoretical point of view, hexavalent S and pentavalents N and P
as polar atoms. Indeed, in these cases, all their peripheral electrons are
involved in bondings. We propose to define PSA2 using the initial definition
extended to O, S, N, P, with the exception of hexavalent S and pentavalents N
and P. In order to test this hypothesis, the three expressions PSA1, PSA2 and
PSA3 have been applied in a QSAR to a physiological phenomenon called comfort
olfactory perceived intensity, for the human responses to 186 odorants
(QSAR stands for Quantitative Structure Activity Relationship). The PSA2
expression has been selected as the more suitable, associated with two other
molecular properties (molar refraction and Van der Waals molecular volume).