Four new organotin(IV) chlorin derivatives, [chlorin = chlorin-e6 = 21H,23H-porphine-2-propanoic acid, 18-carboxy-20-(carboxymethyl)-8-ethenyl-13-ethyl-2,3-di-hydro-3,7,12,17-tetramethyl-(2S-trans)–], with formula (R2Sn)3(chlorin)2 Æ 2H2O (R = Me,n-Bu) and (R3Sn)3chlorin Æ 2H2O (R = Me, Ph) have been synthesized. The solid state and solution phase structures have been investigatedby FT-IR, 119Sn Mo¨ssbauer, 1H and 13C NMR spectroscopy. In the solid state, (R2Sn)3(chlorin)2 Æ 2H2O complexes containsix coordinated Sn(IV), in a skew trapezoidal environment by forming trans-R2SnO4 polymeric units. As far as (R3Sn)3chlorinÆ 2H2O complexes are concerned, Sn(IV) is five coordinated in a polymeric (oligomeric) trigonal bipyramidal environmentand eq-R3SnO2 units, in the solid state. In saturated solutions, a polymeric structure comparable to the solid phase, with carboxylategroups of the ligand behaving in monoanionic bidentate fashion bridging Sn(IV) atoms, was detected for the (Me3Sn)3chlorinÆ 2H2O complex, while in more diluted ones a tetrahedral configuration for the trimethyltin(IV) moieties was observed.Cytotoxic activity of the novel organotin(IV) chlorin was investigated in order to assay the effect on sea urchin embryonic development.The results obtained demonstrated that (n-Bu2Sn)3(chlorin)2 Æ 2H2O and (Ph3Sn)3chlorin Æ 2H2O exerted the antimitoticeffect on the early stages of sea urchin development. In addition, the cytotoxic effect exerted by (n-Bu2Sn)3(chlorin)2 Æ 2H2Oappeared with necrosis of the blastomeres, which were clearly destroyed. After treatment with (Ph3Sn)3chlorin Æ 2H2O, a programmedcell death was triggered, as shown by light microscope observations through morphological assays. The apoptotic eventsin 2-cell stage embryos revealed: (i) DNA fragmentation, with the TUNEL reaction (terminal deoxynucleotidyl transferase-mediateddUTP nick end labelling); (ii) phosphatidylserine translocation in the membrane, with Annexin-V assay and (iii) cytoplasm blebbing,with the TUNEL reaction. The results demonstrated that the novel compound (Ph3Sn)3chlorin Æ 2H2O was the most toxic derivative,by exerting antimitotic effect very early and by triggering apoptosis in the 2-cell stage of sea urchin embryonic development.
|Numero di pagine||12|
|Rivista||Journal of Inorganic Biochemistry|
|Stato di pubblicazione||Published - 2005|
All Science Journal Classification (ASJC) codes
- Inorganic Chemistry