抄録
Procedures for the estimation of the novel quantitative structure-activity relationship (QSAR) descriptor σS°, representing the contributions from both dispersion and repulsion interactions, have been presented for the poly-substituted benzene derivatives.Observed values σS° for C6H6-nRn (R=F, Cl, Me, Et : n=2-6)can be given by the equation σS°(Rn)=a log n+b, where the slope a and the intercept b are also linear against σS°(mono). Consequently, the slope a and the intercept b estimated from σS°(mono) and log n afford σS° for poly-substituted benzene derivatives having an optional set of substituent groups. The values thus obtained agreed well with the observed ones, and were also found to be linear against ΣσS°(mono), where the correction of the number of symmetry should be taken into account.Furthermore, the net increases of polarizabilities Δα for the tetra-, penta-, and hexa-substituted benzene series from benzene reference are approved to be expressed by the linear relation against ΣΔα(mono).
