Synthesis, Characterization, Antimicrobial and Pesticidal Activity of Organoarsenic(iii) and Organoantimony(iii) Complexes with N

Some new Sb(III) and As(III) complexes of N∩S donor ligands N’[1-(2-oxo-2H-chrome-3yl-ethylidene] hydrazinecarbodithionic acid methyl ester (L1H) and N’ [1-(2-oxo-2H-chrome-3yl ethylidene] -hydrazinecarbodithionic acid benzyl ester (L2H) have been synthesized. All the synthesized compounds were characterized by elemental analyses, melting point determinations and a combination of electronic, IR, 1H NMR, and X-ray diffraction spectroscopic techniques. These studies showed that the ligands coordinated to organoantimony and organoarsenic in a monobasic bidentate manner through sulfur and nitrogen donor system. Thus, tetra and pentacoordinated environments around the antimony and arsenic atom have been proposed. In order to evaluate the effect of metal ions upon chelation, both the ligands and their complexes have been screened for their antimicrobial activity against the various pathogenic bacterial and fungal strains. The results indicate that the metal complexes are more potent antimicrobial agents than the parent ligands. Further, the ligands and their corresponding metal complexes have been tested for their pesticidal activity against the Corcyra cephalonica. The results of pesticidal screening are quite promising. INTRODUCTION: Metal complexes of Schiff bases derived from S-alkyl esters of dithiocarbazic acid have been the subject of a large number of studies due probably to their interesting properties 1 and potentially beneficial biological activities 2-3 . Coumarin derivatives constitute an important class of heterocyclic compounds with anticoagulant 4 , insecticide 5 , antibacterial 6 , and pharmacological properties. The number and diversity of nitrogen and sulfur chelating agents used to prepare new coordination and organometallic compounds have increased rapidly during the past few years 7-9 . Sulfur compounds and their metal complexes have antimicrobial activity and showed a high dependence on their substituents 10-11 . QUICK RESPONSE CODE DOI: 10.13040/IJPSR.0975-8232.5(12).5260-66 Article can be accessed online on: www.ijpsr.com DOI link: http://dx.doi.org/10.13040/IJPSR.0975-8232.5(12).5260-66 Organic compounds containing –C6H4S moiety are well known for their significant biological activities. The activity may be due to the presence of multi-coordination centers having the ability to form stable chelates with the essential metal ions which the organisms need in their metabolism. Interest in metal complexes of sulfur-nitrogen chelating agents, especially those formed from Smethyl/benzyl esters of dithiocarbazic acid has been stimulated by their interesting physicochemical properties and potentially useful pharmacological properties 12 . Organoarsenicals were the first compounds applied for the successful treatment of syphilis (they have since been replaced by penicillin) and have been used as feed additives in livestock to prevent bacterial and parasitic infections. Organoarsenic(III) compounds are known to be biologically active. Antimicrobial activities of some arsenic(III) complexes with Schiff bases have been evaluated 13 . The toxicity as well as