Organometallic complexes with biological molecules. XI. Solid state and in vivo investigations of some diorganotin(IV)-chloramphenicol and cycloserine derivatives

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• 作者：Pellerito ; A. ; Fiore ; T. ; Pellerito ; C. ; Fontana ; A. ; Di Stefano ; R. ; Pellerito ; L. ; Cambria ; M.T. ; et. al.
• 关键词：Organotin ; Antibiotics ; Chloramphenicol ; D-cycloserine ; Infrared ; Mö ; ssbauer ; NMR ; Ascidian eggs ; Development
• 刊名：Journal of Inorganic Biochemistry
• 出版年：1998
• 出版时间：December, 1998
• 年：1998
• 卷：72
• 期：3-4
• 页码：115-125
• 全文大小：400 K

文摘

Diorganotin(IV) derivatives of chloramphenicol, {=D-(-)threo-2,2-dichloro-N-[β-hydroxy-α-(hydroxymethyl)-β-(4-nitrophenyl)ethyl]acetamide (=Hchloramph)}, and D-cycloserine, {=(R)-4-amino-3-isoxazolidone [=Hcyclos]} have been prepared. The stoichiometries of the obtained compounds were R₂SnClantib and R₂Snantib₂ (antib⁻¹=chloramph⁻¹, R=methyl and phenyl; antib⁻¹=cyclos⁻¹, R=methyl). The solid state configuration of the complexes was investigated by I.R. and Mössbauer spectroscopy, from which structural hypotheses were inferred. In particular, the experimental data suggested monomer structures both for R₂Sn(IV)Clchloramph and R₂Sn(IV)chloramph₂, in which chloramphenicolate anion behaved as monoanionic monodentate ligand through the oxygen atom of the deprotonated secondary alcoholic group, with formation of tetrahedral R₂SnOCl and R₂SnO₂ environments. In R₂Sn(IV)Clcyclos and R₂Sn(IV)cyclos₂ derivatives, Mössbauer spectroscopy, and in particular the narrowness of the full width at half height of the resonant peaks, Γ₁ and Γ₂, suggested the occurrence of two different absorbing tin sites with different environments around the tin(IV) atoms. According to calculations performed by applying the point charge model formalism, one site was constituted by a tin(IV) tetrahedrically coordinated by monoanionic monodentate cycloserinate groups, through the oxygen atom of the resonance stabilised hydroxamate anion, originating R₂SnClO and R₂SnO₂ polyhedrons both in R₂Sn(IV)Clcyclos and R₂Sn(IV)cyclos₂, respectively. The second site would correspond to a tin(IV) in a polymeric octahedral configuration with Me₂SnCl₂ON and Me₂SnO₂N₂ environments, in Me₂Sn(IV)Clcyclos and Me₂Sn(IV)cyclos₂ derivatives, respectively, in which the second donor atoms was the amino nitrogen atom. ¹H and ¹³C NMR spectra, of both chloramphenicol and its diorganotin(IV) derivatives were carried in DMSO-d₆ solution, in which R₂Sn(IV)Clchloramph and R₂Sn(IV)chloramph₂ underwent total, (R=Me), or partial, (R=Ph), dissociation. As far as the organotin(IV)-D-cycloserine derivatives were concerned, ¹H and ¹³C NMR spectra, also carried out for the free D-cycloserine, showed that, owing to the coordinating properties of the solvent, octahedral and trigonal bipyramidal isomers were present in DMSO solution of Me₂Sn(IV)Clcyclos and Me₂Sn(IV)cyclos₂. Finally, the cytotoxic activity of the free chloramphenicol, D-cycloserine and of their dimethyltin(IV) derivatives has been investigated towards Ciona intestinalis and Ascidia malaca fertilised eggs, at different developing stages.