Asymmetric synthesis of threonine and retroracemization of amino acids using Ni(II) complexes of Schiff bases with S-2-n-(N?-benzylprolyl)aminobenzaldehyde

Autor: N. I. Chernoglazova, Konstantin A. Kochetkov, N. S. Garbalinskaya, V. M. Belikov, S. V. Vitt, M. B. Saporovskaya, E. A. Paskonova, Victor I. Maleev, Vladimir I. Bakhmutov, M. G. Ryzhov, Yu. N. Belokon
Rok vydání: 1984
Předmět:
Zdroj: Bulletin of the Academy of Sciences of the USSR Division of Chemical Science. 33:738-746
ISSN: 1573-9171
0568-5230
DOI: 10.1007/bf00947824
Popis: 1. Complexes of Ni(II) with Schiff bases of 2-N-(2′-S-N-benzylpyrrolidin-2-carbonyl)aminobenzaldehyde (S-BPaB) with glycine and valine have been synthesized in which the Ni ion is coordinated with the N atoms of the proline fragment, of the aldimine group, of the ionized amide, and with the carboxyl group. 2. The presence has been shown of enantioselective effects in complexes of Schiff bases of S-BPAB with R,S-amino acids with Ni(II) which increase with an increase in volume of the amino acid side chain. The enantiomer excess for the complex with S-Val was 78%. 3. The retroracemization of alanine, valine, norvaline, phenylalanine, phenylglycine, and tryptophan was carried out using S-BPAB and Ni(II) with enantiomer yields of 15, 78, 42, 40, 39, and 64% respectively. 4. The asymmetric synthesis of S-threonine has been effected by condensing acetaldehyde with (S-BPAB-Gly)·Ni(II) on catalysis with Et3N with a S-Thr and S-allo-Thr ratio of 1∶2 and enantiomer yield of 86 and 76% respectively. An increase in pH led to a reduction in enantiomer yield and reversal of the sign of the enantioselective effect. 5. A method has been developed for enantiomer analysis of tryptophan using high-pressure liquid chromatography as has a GLC method for difficult amino acids using a high-temperature chiral chromatographic phase, viz., N-heptadecanoyl-S-Val tert-butylamide.
Databáze: OpenAIRE
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