Synthesis, spectral and biological studies of organosilicon(IV) complexes of Schiff bases derived from amino acids

Several new organosilicon(IV) complexes of the type Me3Si(L/L') [where L/L'= anions of the Schiff bases derived from the condensation of 2-methoxybenzaldehyde (HL) or acetophenone (HL') with glycine (HL-1/HL'-1), L-leucine (HL-2/HL'-2). L-methionine (HL-3/HL'-3), DL-alpha -alanine (HL-4/HL'-4) and L-valine (HL-5/HL'-5)] have been synthesized and characterized by elemental analyses, molar conductance, electronic, infrared and multi-nuclear magnetic resonance (H-1 and C-13) studies. All the complexes are non-electrolytes. A pentacoordinate, trigonal-bipyramidal geometry is suggested for all of the complexes. The in vitro antimicrobial activity of the trimethyl- and triphenylsilicon(IV) complexes has also been screened against bacteria (E, coli, Rhizobium meliloti, Aeromonas formicans, Pseudomonas putida, Staphyllococcus aureus) and fungi (Penicillium notatum, Verticillium dahliae, Aureobasidium pullulans and Aspergillus niger), and the complexes were found to be active in this respect.