Abstract—Solubility, partition phenomena and lipophilicity are the three important physico-chemical parameters to be screened at early stage of the drug development process. Solubility of solid compound in solvent is governed by interactions between molecules in the crystal lattice, intermolecular interactions in the solution and the entropy changes accompying fusion and dissolution. N-arylhydroxamic acids shows drug likeliness therefore, the hydrogen bond donor (HBD), hydrogen bond acceptor (HBA) and solubility ratio (SO/SW) of three such molecules N-phenylbenzohydroxamic acid, N-phenyl-4-nitrobenzohydroxamic acid and N-phenyl-4- methyl-3-nitrobenzohydroxamic acid, were measured in water and co-solvent system by shake-flask method following the measurement of the concentration by UV spectroscopy. The co-solvents are methanol, ethanol, 1-propanol, 1-octanol and chloroform. The solubility ratio gives comparable estimates to that of the group contribution method for estimating the lipophilicity of the molecules. The values obtained after regression analysis are in the range from 0.996 to 0.999, which shows that the solubility ratio gives good estimate of the partition coefficient for the solutes used in the present study.

Index Terms—Hydroxamic acid, Partition coefficient, Solubility, Solubility ratio.

Authors are with School of Studies in Chemistry, Pt. Ravishankar Shukla University, Raipur (C.G.) 492010, India (e-mail: rama.pande11@ gmail.com).

Cite: Sandhya Patre, Piyush Thakur, and Rama Pande, "Solubility and Hydrophobic Descriptors of N-Arylhydroxamic Acids," International Journal of Bioscience, Biochemistry and Bioinformatics vol. 1, no. 4, pp.  267-270 , 2011.