ISSN:
0268-2605
Schlagwort(e):
Organolead(IV)
;
N-protected aminoacids
;
dipeptides
;
structures
;
complexes
;
Chemistry
;
Organic Chemistry
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
The diphenyllead(IV) derivatives of N-benzoyl-(glycine, DL-alanine); N-formyl and N-acetyl-L-phenylalanine; N-monochloroacetyl-L-phenylalanine; N-benzoyl-(glycylglycine, DL-alanylglycine), and N-formyl- N-acetyl- and N-monochloroacetyl-(L-phenylalanylglycine) have been prepared in 1:2 molar ratio by reaction of diphenyllead dichloride with the appropriate amino-acid or dipeptide. Corresponding triphenyllead(IV) derivatives have been prepared in 1:1 molar ratio by reaction of triphenyllead chloride with the thallium(I) salts of the amino-acid or the dipeptide. These complexes have been characterized by elemental analysis, IR and 1H NMR spectral studies. A polymeric hexacoordinated octahedral structure for diphenyllead(IV), and a five-coordinated distorted trigonalbipyramidal chain-type structure for triphenyllead(IV), complexes is confirmed by IR spectra. The carboxylate group acts in a bidentate manner, not as in diorgano and triorganotin(IV) complexes with these acids, where it is monodentate. The available bonding sites such as amide and peptide carbonyl (CO) and amide and peptide nitrogen atoms are not involved in bonding with lead (IV) and thus are available for bonding with the biological systems. The presence of different N-protecting groups does not affect the coordination sites around lead(IV). The triphenyllead(IV) compounds are relatively more stable than the diphenyllead(IV) compounds.
Zusätzliches Material:
4 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/aoc.590040407
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