Vol. 7, Issue 12, Part A (2025)

Hydroxamic acids are a group of weak organic acids having the general formula RC(=O)N(R^’)OH, shows a wide spectrum of activities in analytical, agricultural, biological and medicinal fields. The logarithmic n-octanol/water partition coefficient (logP_O/W) is an important property for pharmacology, toxicology and medicinal chemistry. Some commonly available software including XLOGP, KowWin, CLOGP, ALOGPS and miLOGP were used to estimate the log P_O/W values of the hydroxamic acids. Moderate correlation were obtained between the shake flask derived logP_O/W and the software computed logP_O/W, with squared correlation coefficients (R²) ranging from 0.4022 to 0.5688.

Quantitative structure-property relationship (QSPR) for the lipophilic behaviour, logP_(O/W), of N-arylhydroxamic acid (HAs) is analysed using the molecular descriptors by partial least square (PLS) regression. The cross-validation Q² cum values for the optimal QSPR model of HAs is above 0.860 (remarkably higher than 0.500), indicating good predictive-abilities for logP_O/W values of HAs. The resulting QSPR model shows that logP_O/W values of HAs are mainly governed by molar volume (Vx), excess molar refraction (XRM), energy GAP (E_HOMO- E_LUMO), hydrogen bond parameters (α, β) and chlorine atoms attached in upper or/and lower phenyl rings (I_Cl).