Crystal Structure and Conformation Study of 3-Methyl-2, 6-bis (4-chlorophenyl) Piperidin-4-one Thiosemicarbazone Derivative

Abstract

Thiosemicarbazones (TSCs) are very versatile tridentate ligands having the ability to bind transition metal ions by bonding through sulfur and hydrazinic terminal nitrogen atoms. TSC also inhibits the enzyme ribonucliotide diphosphate reductase (RDR) which is involved in the synthesis of DNA precursors in the mammalian cells. One of the important heterocyclic thiosemicarbazones, the title compound (MBCPT) has been synthesized based on the Mannich reaction and it was characterized by X-ray diffraction methods. The crystallographic data of MBCPT are: C19H20Cl2N4S; M.W = 407.35, Monoclinic, space group, P21/n, with cell parameters a = 12.053(8) A, b = 11.431(10) A, c = 14.695(7) A, β = 95.82(4)o; V = 2014(2) A3, Z = 4, Dcal = 1.343 Mg/m3, λ (Cu K α ) = 1.54184 A. The ring piperine adopts chair conformation. The phenyl rings are oriented equatorially at 2 and 6th positions of the piperidine ring. Molecular packing can be viewed as a dimer held together by two N–H⋯S intermolecular hydrogen bonds. Molecules are tightly bound in the unit cell by C–H⋯N, N–H⋯S and N–H⋯N types inter and intra molecular hydrogen bonds. One of the piperidin-4-one thiosemisemicarbazones, MBCPT, has been synthesized and its structural chemistry has been proved by X-ray crystallographic study.