2-(4-Phenyl-5-pyridin-2-yl-4H-1,2,4-triazol-3-yl)cyclohexanecarboxylic Acid and Its DMSO Solvate: Synthesis, Crystal Structure and Biological Activity

A new 1,2,4-triazole derivative, 2-(4-phenyl-5-pyridin-2-yl-4H-1,2,4-triazol-3-yl)cyclohexanecarboxylic acid, C20H20N4O2 (I), and its dimethyl sulfoxide solvate 1:1 (II) have been synthesized and their crystal structure was established. Compound (I) was screened for its anti-proliferative and antiinflammatory activity. Structural analysis indicated the substantial difference between two symmetry independent molecules in (I) and this in (II), it manifests in the relative orientation of pyridine/phenyl and triazole rings, as well as in the orientation of carboxyl group with respect to cyclohexane ring. The molecules A and B in the crystal (I) form two hydrogen-bonded chains through O-H-carboxyl and N-triazole atoms, giving separate catemers of symmetry independent molecules. The catemer of (IA) running along the 2(1) axis is homochiral, while the catemer (IB) is racemic-formed about the c glide plane. In the crystalline solvate (II) complexation of (I) with DMSO induced enantiomeric self-resolution. Obtained crystals are racemic twins, in which each part is built of one enantiomer of (I) having the relative configuration 11S,12R or 11R,12S. A pair of host-guest molecules is linked by the O-H-carboxyl center dot center dot center dot O-DMSO hydrogen bond.