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Titolo:
Enantioselective synthesis of beta-amino acids. Part 10: Preparation of novel alpha,alpha- and beta,beta-disubstituted beta-amino acids from (S)-asparagine
Autore:
Juaristi, E; Balderas, M; Lopez-Ruiz, H; Jimenez-Perez, VM; Kaiser-Carril, ML; Ramirez-Quiros, Y;
Indirizzi:
Inst Politecn Nacl, Ctr Invest & Estudios Avanzados, Dept Quim, Mexico City 07000, DF, Mexico Inst Politecn Nacl Mexico City DF Mexico 07000 ico City 07000, DF, Mexico
Titolo Testata:
TETRAHEDRON-ASYMMETRY
fascicolo: 18, volume: 10, anno: 1999,
pagine: 3493 - 3505
SICI:
0957-4166(19990910)10:18<3493:ESOBAP>2.0.ZU;2-E
Fonte:
ISI
Lingua:
ENG
Soggetto:
ASYMMETRIC-SYNTHESIS; ALPHA-ALKYLATION; STEREOSELECTIVE SYNTHESIS; ASPARTIC ACIDS; PEPTIDES; 1-BENZOYL-2(S)-TERT-BUTYL-3-METHYLPERHYDROPYRIMIDIN-4-ONE; REARRANGEMENT; DERIVATIVES; CHIRALITY; ALDEHYDES;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
35
Recensione:
Indirizzi per estratti:
Indirizzo: Juaristi, E Inst Politecn Nacl, Ctr Invest & Estudios Avanzados, Dept Quim, Apartado Postal 14-740, Mexico City 07000, DF, Mexico Inst Politecn Nacl Apartado Postal 14-740 Mexico City DF Mexico 07000
Citazione:
E. Juaristi et al., "Enantioselective synthesis of beta-amino acids. Part 10: Preparation of novel alpha,alpha- and beta,beta-disubstituted beta-amino acids from (S)-asparagine", TETRAHEDR-A, 10(18), 1999, pp. 3493-3505

Abstract

Perhydropyrimidinone (S)-1 is alkylated with very high diastereoselectivity to give trans products (2S,5R)-3, (2S,5R)-4 and (2S,5R)-5. Dialkylation of (S)-1 also proceeds with complete stereoselectivity to afford adducts (2S,5R)-6, (2S,5S)-6, (2S,5R)-7 and (2S,5S)-7. Hydrolysis (6N HCl, 100 degreesC) of monoalkylated derivative (2S,5R)-3 gives enantiopure alpha-substituted beta-amino acid (R)-8. Hydrolysis of dialkylated adducts 6 and 7 affordsenantiopure alpha,alpha-disubstituted beta-amino acids (R)- or (S)-9 and (R)- or (S)-10. Related iminoester (2S,6S)-2 is alkylated with complete diastereoselectivity to give products (2S,6S)-11-13 whose hydrolysis under relatively mild conditions (2N CF3CO2H, CH3OH, 100 degrees C) affords enantiopure N-benzoylated beta,beta-disubstituted beta-amino acid esters (S)-14-16, with intact double bonds in the olefinic substituents. (C) 1999 Elsevier Science Ltd. All rights reserved.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 27/11/20 alle ore 22:08:35