Publicação
Synthesis and reactivity of beta-bromo-beta-substituted dehydroalanines
| Resumo: | The methyl ester of N-tert-butoxycarbonyl-(Z)-beta-bromo-beta-(1,2,4-triazol-1-yl)dehydroalanine was prepared by treatment of the methyl ester of N-tert-butoxycarbonyl-(E)-beta-(1,2,4-triazol-1-yl)dehydroalanine with N-bromosuccinimide (NBS), followed by Et3N. The reactivities of this compound and of our previously synthesized methyl ester of N-tert-butoxycarbonyl-beta,beta-dibromodehydroalanine towards several nucleophiles were studied, and it was found that these compounds react with oxygen nucleophiles to give the corresponding alpha-alkoxy-beta,beta-disubstituted alanines. Addition to the a-carbon atom also occurred when the beta,beta-dibromodehydroalanine derivative was treated with primary amines, giving alpha-amino-beta,beta-dibromoalanines. Treatment of the beta-bromo-beta-(1,2,4-triazol-1-yl)dehydroalanine derivative with amines gave alpha-(alkylamino)-beta-(alkylimino)alanines in high yields. These iminoalanines afforded alpha-aminoglycines when treated with silica in dichloromethane. (c) Wiley-VCH Verlag GmbH & Co. |
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| Autores principais: | Ferreira, Paula M. T. |
| Outros Autores: | Monteiro, Luís S. |
| Assunto: | Nonproteinogenic amino acids Alanine derivatives Glycine derivatives |
| Ano: | 2006 |
| País: | Portugal |
| Tipo de documento: | artigo |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Universidade do Minho |
| Idioma: | inglês |
| Origem: | RepositóriUM - Universidade do Minho |
| Resumo: | The methyl ester of N-tert-butoxycarbonyl-(Z)-beta-bromo-beta-(1,2,4-triazol-1-yl)dehydroalanine was prepared by treatment of the methyl ester of N-tert-butoxycarbonyl-(E)-beta-(1,2,4-triazol-1-yl)dehydroalanine with N-bromosuccinimide (NBS), followed by Et3N. The reactivities of this compound and of our previously synthesized methyl ester of N-tert-butoxycarbonyl-beta,beta-dibromodehydroalanine towards several nucleophiles were studied, and it was found that these compounds react with oxygen nucleophiles to give the corresponding alpha-alkoxy-beta,beta-disubstituted alanines. Addition to the a-carbon atom also occurred when the beta,beta-dibromodehydroalanine derivative was treated with primary amines, giving alpha-amino-beta,beta-dibromoalanines. Treatment of the beta-bromo-beta-(1,2,4-triazol-1-yl)dehydroalanine derivative with amines gave alpha-(alkylamino)-beta-(alkylimino)alanines in high yields. These iminoalanines afforded alpha-aminoglycines when treated with silica in dichloromethane. (c) Wiley-VCH Verlag GmbH & Co. |
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