54594-06-8Relevant articles and documents
Synthesis of chiral cyclic nitrones via a nitrosoketene intermediate and their use for the complete EPC synthesis of nonproteinogenic amino acids
Katagiri, Nobuya,Okada, Makoto,Kaneko, Chikara,Furuya, Toshio
, p. 1801 - 1804 (1996)
New cyclic chiral nitrones constituting two diastereomers were synthesized by the reaction of isonitroso Meldrum's acid with l-menthone via a nitrosoketene intermediate. Both nitrones reacted with allyltrimelhylsilane diastereoselectively to give the corresponding isoxazolidine derivatives as sole products, which were converted to (S)- and (R)-allylglycines in ca. 100% ee, respectively.
Epoxy amino acids produced from allylglycines intramolecularly cyclised to yield four stereoisomers of 4-hydroxyproline derivatives
Krishnamurthy, Suvratha,Arai, Toru,Nakanishi, Kanae,Nishino, Norikazu
, p. 2482 - 2490 (2014/01/06)
Derivatives of 2-amino-4-pentenoic acid (allylglycine) were efficiently resolved using Subtilisin or acylase. The side-chain unsaturated bond of the enantiomerically pure amino acid with tert-butoxycarbonyl (Boc) protection was smoothly epoxidized with m-chloroperbenzoic acid. When the Boc protection of the amino group was removed, the amino group intramolecularly attacked the side-chain epoxide, generating compounds with five-membered rings: the 4-hydroxyproline derivatives. Two diastereomeric products were formed through the cyclisation reaction, for example, (2S,4S)-4-hydroxyproline benzyl ester (cis-8) and (2S,4R)-4-hydroxyproline benzyl ester (trans-8) were formed from (2S)-amino acid with a side-chain epoxide. Compound (2S,4S)-4-hydroxyproline benzyl ester (cis-8) was transformed to a lactone (cis-hydroxyproline lactone, 10) with the removal of benzyl alcohol. The cis-conformation was essential for the intramolecular ester exchange reaction; in fact, no lactone formation was observed for the trans isomer (trans-8). The separation of cis-hydroxyproline lactone and the trans-isomeric hydroxyproline benzyl ester was facile and clear, in contrast to the difficult separation of cis- and trans-hydroxyproline derivatives. Thus, two diastereomers of hydroxyproline derivatives for l-hydroxyproline and also for d-hydroxyproline were obtained, i.e., four diastereomers of hydroxyproline derivatives.
Novel preparation of chiral α-amino acids using the Mitsunobu-Tsunoda reaction
Noisier, Anais F. M.,Harris, Craig S.,Brimble, Margaret A.
supporting information, p. 7744 - 7746 (2013/09/02)
An efficient synthesis of racemic or optically active α-amino acids by modified-Mitsunobu alkylation of a racemic or chiral glycine template from alcohols was developed. Libraries of amino acids were prepared in moderate to good yield with good to high enantioselectivity. This simple method widens the scope for preparation of structurally diverse amino acids.
Phase-transfer enantioselective monoalkylation of prochiral nickel(ii) complexes catalyzed by 3,3′-bis[hydroxy(diphenyl)methyl]-1,1′- binaphthyl-2,23′-diol (BIMBOL) as a route to α-amino acids
Belokon,Maleev,Samoilichenko,Moskalenko,Hakobyan,Saghyan
, p. 2344 - 2349 (2013/10/01)
An achiral nickel complex with a Schiff base derived from glycine was alkylated with alkyl halides under conditions of asymmetric phase-transfer catalysis. The chiral tetraol (R)-BIMBOL was employed as a catalyst. The enantiomeric purity of the alkylation products was up to 88%. Subsequent decomposition of the complexes afforded the corresponding a-amino acids.