Study of lipophilicity and application of selected structural descriptors in QSAR analysis of nicotinic acid derivatives. Investigations on RP18WF254 plates. Part II

Abstract

Nicotinic acid (NAC) and its derivatives methyl nicotinate (MN), ethyl nicotinate (EN), isopropyl nicotinate (IPN), butyl nicotinate (BN), hexyl nicotinate (HN), benzyl nicotinate (BNN), nicotinamide (NAM), and N -methylnicotinamide (MNAM) have been investigated on RP18WF 254 HPTLC plates with methanol-water in different volume proportions as mobile phases. Linear relationships were obtained between R M values of the compounds and the volume fraction of methanol in the mobile phase. Retention values R M were extrapolated to zero methanol content and the lipophilicity values R M0(RP18WF254) obtained were compared with measured partition coefficients (log P exp ) and with partition coefficients ( A log P s, IA log P , C log P , log P Kowin , and x log P ) calculated using five different software products. The most significant correlation was found between R M0(RP18WF254) and A log P s values. The values of chromatographic lipophilicities R M0(RP18WF254) and ϕ 0(RP18WF254) indicate that lipophilicity of the ...