ISSN 1070-3284, Russian Journal of Coordination Chemistry, 2009, Vol. 35, No. 5, pp. 373–380. © Pleiades Publishing, Ltd., 2009. 373 1 INTRODUCTION To overcome the alarming problem of microbial resistance to antibiotics, the discovery of novel active compounds against new targets is a matter of urgency. However, plant-based drugs have shortened the life span of the source of material. There is a continuous search for more potent and cheaper raw material to feed the industry. Coordination compounds exhibit different characteristic properties, which depend on the metal ion to which they are bound, the nature of the metal, as well as the type of ligand. These metal complexes have found extensive applications in various fields of human interest. The nature of a coordination compound depends on the metal ion and the donor atoms, as well as on the structure of the ligand and the metal–ligand interaction [1]. With increasing knowledge of the prop- erties of functional groups, as well as the nature of donor atoms and the central metal ion, ligands with more selective chelating groups, i.e., imines or azome- thines which are more commonly known as Schiff bases, are used for complex formation studies. It is 1 The article is published in the original. reported that the rapidly developing field of bioinor- ganic chemistry is centered on the presence of coordi- nation compounds in living systems [2]. Although syntheses of S-benzyldithiocarbazate Schiff bases and their complexation products were reported in the recent past [3–5], the evaluation of their biological properties has not been described. In addi- tion, their complexes with transition metals have exten- sively been studied [6–8]. A variety of complexes of phenyldihydroxyborane with substituted dihiocarba- zates were also prepared in a benzene solution. The pathogenicity of microbial infection associated with the complexes has been subjected to a variety of biointer- action studies and the results are discussed [9]. Boron complexes of benzothiazolines with N ∩ S donor system are gaining enormous importance on account of their inherent biological potential [10]. A number of boron azomethine derivatives have been reported, and these were synthesized by the reaction of isopropoxyborane and phenyldihydroxyborane [11]. A variety of organolead compounds possess antimi- crobial and fertility regulatory activities [12–13]. The antimycobacterial activities of some lead compounds Organoboron(III) and Organolead(IV) Complexes as Antimicrobial and Antimycobacterial Agents: Synthetic, Structural, and Biological Aspects 1 M. Swami a , K. Mahajan a , S. Arya b , S. K. Mehla c , and R. V. Singh a a Department of Chemistry, University of Rajasthan, Jaipur 302004, India b Department of Zoology, University of Rajasthan, Jaipur 302 004, India c Department of Chemistry, College of Engineering and Technology, Bikaner–334004 e-mail: rvsjpr@hotmail.com Received April 29, 2008 Abstract—Phenylboron(III) and triorganolead(IV) derivatives of the types PhB(OH)(DTCZ), PhB(DTCZ) 2 , and Ph 3 Pb(DTCZ) (where DTCZ – is the anion of a S-benzyldithiocarbazate ligand) have been synthesized by the substitution reactions of phenylboronic acid and triphenyllead chloride with S-benzyldithiocarbazate. The resulting complexes have been characterized by elemental analyses, molecular weight determinations, and con- ductivity measurements. The mode of bonding has been established on the basis of infrared and 1 H, 13 C, and 11 B NMR spectroscopic studies. Probable tetrahedral and trigonal bipyramidal structures for the resulting deriv- atives have been proposed. The X-ray powder diffraction study of the compound [PhB(OH)(L 1 )] was carried out in order to have an idea about the molecular symmetry of the compound. The results show that the com- pound belongs to the orthorhombic crystal system. In the quest for better fungicides and bactericides, the stud- ies were conducted to assess the growth inhibiting potential of the synthesized complexes against various fungal and bacterial strains. The studies demonstrate the concentration reached levels which are sufficient to inhibit and kill the pathogens. The antimycobacterial effects of the organolead(IV) compounds were also examined. The results obtained indicated that the compounds display antimycobacterial activity. DOI: 10.1134/S1070328409050108