ISSN:
0899-0042
Keywords:
β-methylaspartase
;
alkylfumarates
;
(2S,3S)-3-methylaspartic acid
;
(2S,3S)-3-isopropylaspartic acid
;
bioconversion
;
(3S,4R)-benzyl 3-alkylmalolactonates
;
poly[benzyl-β-(2S,3S)-3-alkylmalates]
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
(2S,3S)-3-methyl- and 3-isopropylaspartic acids were synthesized by bioconversion of the corresponding alkylfumarates (mesaconate and 3-isopropylfumarate) using β-methylaspartase from cell-free extracts of Clostridium tetanomorphum. Optically pure (2S,3S)-3-alkylaspartic acids were transformed in several steps to benzyl (3S,4R)-3-alkylmalolactonates without any racemization of the two chiral centers. These optically active α,β-substituted-β-lactones were polymerized by anionic ring opening polymerization yielding optically active semi-crystalline polyesters. 13C NMR analysis of poly[benzyl β-3-isopropylmalate] in CDCl3 has shown that only the iso-type stereosequence is present in the polymer, indicating that the macromolecular chain is constituted by the only units of benzyl β-(2S,3S)-3-isopropylmalate monomer. The polymerization reaction was done without any racemization of the two stereogenic centers as in the case of benzyl (3S,4R)-3-methylmalolactonate. © 1996 Wiley-Liss, Inc.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
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