申请人:Hildbrand Stefan
公开号:US06878829B2
公开(公告)日:2005-04-12
β-alaninamides of the general formula
Wherein R
1
is hydrogen or C
1-6
alkyl which is unsubstituted or substituted with hyroxy, amino, carboxy, carbamoyl, methylmercapto, guanidino, unsubstituted or substituted aryl or heteroaryl, and R
2
is hydrogen, or R
1
and R
2
together form a group of the formula —(CH
2
)
n
— where n is 3 or 4, and R
3
is hydrogen, a negative charge compensated by an equivalent of an inorganic or organic cation or is C
1-6
alkyl, are prepared, without using an amino-protective group, by reacting the corresponding α-amino acid or the corresponding α-amino acid ester with a cyanoacetic ester to give a cyanoacetamide and by subsequent catalytic hydrogenation. The method is particularly suitable for preparing carnosine (β-alanyl-L-histidine, R
1
=imidazol-4-yl-methyl, R
2
=R
3
=H), a naturally occurring dipeptide which used as a dietary supplement with antioxidative action.
通式为的β-丙氨酰胺衍生物其中R1是氢或C1-6烷基,未取代或取代羟基、氨基、羧基、氨基甲酰、甲硫基、胍基、未取代或取代芳基或杂环芳基;R2是氢,或者R1和R2共同形成公式-(CH2)n-的基团,其中n为3或4;R3是氢,由等量的无机或有机阳离子补偿的负电荷或C1-6烷基。无需使用氨基保护基,通过将相应的α-氨基酸或相应的α-氨基酸酯与氰乙酸酯反应以得到氰乙酰胺,然后进行催化加氢即可制备β-丙氨酰-L-组氨酸(肉碱,R1=咪唑-4-基甲基,R2=R3=H),这是一种天然二肽,具有抗氧化作用,被用作膳食补充剂。