Syntheses, crystal structures, and antimicrobial activities of nickel(II) and cadmium(II) complexes with 4-methylsulfonyl cinnamate and diamines

Two metal complexes, [NiII(mscinn)2(pda)2] (1) and [CdII(mscinn)2(dmeda)2.2H2O] (2) (mscinn?=?4-methylsulfonyl cinnamate, pda?=?propane-1,3-diamine, dmeda?=?N',N'-dimethylethane-1,2-diamine), were synthesized by reacting 4-methylsulfonyl cinnamate with the diamines and metal salts. Their structures were determined by single-crystal X-ray diffraction analysis. Crystal parameters of 1: C26H38N4NiO8S2, M?=?657.43, monoclinic, P21/c, a?=?16.6123(8)?angstrom, b?=?8.5956(4)?angstrom, c?=?11.2047(5)?angstrom, beta?=?107.423(1)degrees, V?=?1526.54(12)?angstrom 3, Z?=?2, D calcd?=?1.430?g?cm-3, F(000)?=?692, mu?=?0.825?mm-1, R 1?=?0.0257, wR 2?=?0.0669. Crystal data of 2: C28H42CdN4O8S2?.?2(H2O), M?=?775.24, monoclinic, P21/c, a?=?9.8278(4)?angstrom, b?=?11.6611(5)?angstrom, c?=?15.3972(7)?angstrom, beta?=?96.195(1)degrees, V?=?1754.26(13)?angstrom 3, Z?=?2, D calcd?=?1.468?g?cm-3, F(000)?=?804, mu?=?0.798?mm-1, R 1?=?0.0299, wR 2?=?0.0770. Antimicrobial activities for 1 and 2 against Escherichia coli, Pseudomonas putida, Bacillus subtilis, and Bacillus cereus had better antibacterial activity than their parent carboxylic acid against Gram-positive bacteria (B. subtilis and B. cereus). The cadmium complex of the cinnamate displayed high inhibitory activity with an MIC value of 5?mu g?mL-1 against P. putida, while the nickel complex also exhibited good inhibitory potency with an MIC value of 5?mu g?mL-1 against B. subtilis.