ORGANOMETALLIC COMPLEXES WITH BIOLOGICAL MOLECULES .7. KYL-TIN(IV)[MESO-TETRA(4-CARBOXYPHENYL)PORPHINATE] AND KYL-TIN(IV)[MESO-TETRA(4-CARBOXYPHENYL)PORPHINATE] DERIVATIVES - SOLID-STATE, SOLUTION-PHASE STRUCTURAL ASPECTS AND IN-VIVO EFFECTS

The synthesis, the structural features and the in vivo biological acti vity of diorganotin(IV) and triorganotin(IV) derivatives of [mesotetra (4-carboxyphenyl)porphine] (H4TPPC) are reported, Derivatives with gen eral formula (R2Sn)(2)TPPC and (R3Sn)(4)TPPC (R = Me, Bu, and Ph) were obtained, and the main information extracted from the infrared and Mo ssbauer spectral data, in the solid state, was in favor of the occurre nce of five-coordinated tin(IV) atoms, in a polymeric trigonal-bipyram idal configuration, attained through two differently coordinated, este rtype and chelating respectively, carboxylate anions in [R2Sn](2)TPPC, while in [Alk(3)Sn](4)TPPC five-coordination of the tin(IV) atom is r eached through bridging carboxylate groups. H-1 and C-13 NMR spectra, in DMSO-d(6) or CDCl3 suggested that the soluble derivatives, at room temperature or at 342 K, were present in solution as simple monomers. The interactions of thyltin)(4)[meso-tetra(4-carboxyphenyl)porphinate] (TMTPPC) and (tributyltin)(4)[meso -tetra(4-carboxyphenyl)porphinate] (TBTPPC) with Bluescript KS(+) plasmid and cultured 3T3 fibroblasts w ere studied. Both compounds have a clear inhibitory effect on the grow th of cultured mouse embryonal fibroblasts (NIH-3T3), TBTPPC being muc h more active, No evidence was found, however, for DNA cleavage by the compounds at molar ratios as high as 1:10 (TMTPPC, TBTPPC/DNA base pa irs). According to our observations, the cytotoxicity of TBTPPC and TM TPPC does not seem to be based on direct interaction with DNA. (C) 199 7 by John Wiley & Sons, Ltd.