New dimeric cyclodiphosph(V)azane complexes of Cr(III), Co(II), Ni(II), Cu(II), and Zn(II): preparation, characterization and biological activity studies.

The complexes of type [CrLCl](2).3.5H(2)O and [ML(H(2)O)](2).nH(2)O in which M = Co(II); n = 1, Ni(II); n = 4, Cu(II); n = 0.5 and Zn(II); n = 2 ions and L is 1,3-dimethyl-2,4-dioxo-2',4'-bis(2iminothiophene)cyclodiphosph(V)azane, were prepared and their structures characterized by elemental analysis, IR, (1)H NMR, (31)P NMR, EPR, XRD, SEM, TGA, mass, molar conductance, magnetic moment and UV-Visible spectra. Antimicrobial activities have been studied using the agar-disc diffusion technique, and the higher antimicrobial activity has been observed for the Chromium(III) complex compared to the other metal complexes.