Biological potential study of metal complexes of sulphonylurea glibenclamide on the house fly, Musca domestica (Diptera-Muscidae): preparation, spectroscopic and thermal characterization.

The ligatation behaviour of sulphonylurea glibenclamide drug is studied in order to give an idea about its potentiality towards some transition metals in vitro systems. Metal complexes of glibenclamide (GCA; H(3)L) drug are prepared and characterized based on elemental analyses, IR, diffused reflectance, magnetic moment, molar conductance and thermal analysis (TG and DTG) techniques. From the elemental analyses data, the complexes are proposed to have the general formulae [M(H(3)L)Cl(n)(H(2)O)(m)].yH(2)O (where M=Cr(III) (n=3, m=1, y=3); Mn(II) (n=2, m=0, y=1); Fe(III) (n=3, m=1, y=0), Co(II) (n=2, m=2, y=0); Ni(II) (n=2, m=2, y=3); Cu(II) (n=2, m=2, y=2) and Zn(II) (n=2, m=0, y=0). The molar conductance data reveal that all the metal chelates are non-electrolytes. IR spectra show that GCA is coordinated to the metal ions in a neutral bidentate manner with OO donor sites of the amide-O and sulphone-O. From the magnetic and solid reflectance spectra, it is found that the geometrical structures of these complexes are octahedral except Mn(II) and Zn(II) complexes which have tetrahedral structure. The thermal behaviour of these chelates is studied using thermogravimetric analysis (TG and DTG) technique. The activation thermodynamic parameters are calculated using Coats-Redfern method. The GCA drug, in comparison to its metal complexes also is screened for its biological activity against house fly, Musca domestica (Diptera-Muscidae). Dose of 5 microg/insect of GCA is topically applied against 3 days old larval instar of M. domestica. Survival of pupal and adult stages has been affected by the complexes of GCA more than larval instars. Morphogenic abnormalities of larvae, pupae and adults are studied. On the other hand pupation and adult emergence program is deteriorated by the effect of different chemicals.