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

Abstract

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) Å, b = 8.5956(4) Å, c = 11.2047(5) Å, β = 107.423(1)°, V = 1526.54(12) Å3, Z = 2, D calcd = 1.430 g cm−3, F(000) = 692, μ = 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) Å, b = 11.6611(5) Å, c = 15.3972(7) Å, β = 96.195(1)°, V = 1754.26(13) Å3, Z = 2, D calcd = 1.468 g cm−3, F(000) = 804, μ = 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 µg mL−1 against P. putida, while the nickel complex also exhibited good inhibitory potency with an MIC value of 5 µg mL−1 against B. subtilis.