Synthesis and antimicrobial activity of new schiff bases having the -SiOR group (R = CH 3 or CH2CH3), and their transition metal complexes

Two new Schiff base ligands containing -SiOCH3 or -SiOCH2CH3 groups, 4-{[(3-trimethoxysilanepropyl)imino] methyl} benzene-1,3-diol (1) Hmsb and 4-{[(3-triethoxysilanepropyl)imino]methyl} benzene-1,3-diol (5) Hesb, have been synthesized by the reaction of 2,4- dihydroxybenzaldehyde with 3-aminopropyltrimethoxysilane and 3-aminopropyltriethoxysilane. Six new transition metal [Cu-II, Ni-II and Co-II] complexes of these Schiff Base ligands were prepared. The complexes are formed by coordination of N, O atoms of the ligands. Their structures were confirmed by elemental analyses, H-1 nmr, i.r. and u.v.-vis. spectral data. The analytical data shows that the metal-to-ligand ratio in the Schiff Base complexes contains silane in 1:2. In addition, the antimicrobial activity of (1) Hmsb and (5) Hesb Schiff ligands, and their [M(msb)(2)] and [M(esb)(2)] type coordination compounds, were investigated.