DIORGANOTIN(IV) COMPLEXES OF PYRIDOXAL THIOSEMICARBAZONE - SYNTHESIS,SPECTROSCOPIC PROPERTIES AND BIOLOGICAL-ACTIVITY

The complexes [SnR2(L)] (R = Me, Et, Bu, Ph; H2L = pyridoxal thiosemic arbazone) have been prepared and characterized. In the light of the sp ectral properties of the complexes in the solid state (IR, mass, Mossb auer) the bideprotonated thiosemicarbazonato anion is O(phenolic)-, N( 3)-, S-bonded to the tin atom which probably has trigonal bipyramidal coordination with N(3) atom and R groups occupying equatorial position s. NMR(H-1, C-13 and Sn-119) data in CDCl3 or DMSO-d(6) suggest that t his coordinative picture remains in these solutions. The ethyl, butyl and phenyl derivatives suppress proliferation of Friend erithroleukaem ia cells (FLC), Of the pyridoxal thiosemicarbazone complexes so far ev aluated, [SnBu2(L)] and [SnPh2(L)] showed the lowest thresholds for in hibition of FLC proliferation. The effects of these compounds on DMSO- induced differentiation of FLC, DNA synthesis and reverse transcriptas e were also assayed. (C) 1998 Elsevier Science Inc. All rights reserve d.