Spectroscopic studies and characterization of Nill and Cull complexes with a nitrogen donor new azamacrocyclic ligand with pendent arms

Department of Chemistry, Zakir Husain College (University of Delhi), JLN Marg, New Delhi-110 002, India E-mail: schandra_00@yahoo.com Department of Chemistry, D. N. College, Meerut, Uttar Pradesh. India E-mail : deepali 101@yahoo.com NSIT (University of Delhi), Sector-3, Dwarka, Uttar Pradesh, India Manuscript received 17 June 2008. revised 23 September 2008, accepted 12 November 2008 The newly synthesised azamacrocyclic ligand L [2,6,12,16,21,22-hexaaza-3,4,5, 13,14, 15-hexamethyltricyclo- [15,3,1,17-11]-docasa-1(2,10,2,5, 7,9,11(22),12,15, 17, 19-decene] was prepared by the reaction of 3-methyl-2,4-pentadionc and 2,6-diaminopyridine. The complexes of Cull and Nill were synthesised with the new macrocyclic ligand. All the complexes were characterized by the molar conductance measurements, magnetic susceptibilit)' measurements, mass, IR, electronic and EPR spectral studies. The molar conductance measurement of the complexes in DMF solution is corresponding to non-electrolytic nature. Thus these complexes may be formulated as [M(L)X2] (where, M = Nill and Cull and X = Cl- and NO3)-. On the basis of spectral studies, an octahedral geometry for Nill complexes and tetragonal for Cull complexes is assigned. The biological activity of the ligand and complexes were screened in vitro against different pathogenic fungi and several bacteria to study their comparative capacity to inhibit the growth