Effective Methods for the Synthesis ofN-Methylβ-Amino Acids from All Twenty Commonα-Amino Acids Using 1,3-Oxazolidin-5-ones and 1,3-Oxazinan-6-ones
作者:Andrew B. Hughes、Brad E. Sleebs
DOI:10.1002/hlca.200690235
日期:2006.11
N-Methyl β-amino acids are generally required for application in the synthesis of potentially bioactive modified peptides and other oligomers. Previous work highlighted the reductive cleavage of 1,3-oxazolidin-5-ones to synthesise N-methyl α-amino acids. Starting from α-amino acids, two approaches were used to prepare the corresponding N-methyl β-amino acids. First, α-amino acids were converted to
应用N-甲基β-氨基酸通常是潜在合成具有生物活性的修饰的肽和其他寡聚体的应用。先前的工作强调了1,3-恶唑烷-5-酮的还原裂解以合成N-甲基α-氨基酸。从α-氨基酸开始,使用两种方法来制备相应的N-甲基β-氨基酸。首先,α -氨基酸转化为Ñ甲基α -氨基酸由所谓的“-1,3-恶唑-5-酮的策略”,将它们再由同系阿恩特-艾斯特方法,得到Ñ-protected Ñ -甲基β -氨基酸选自20种常见衍生α -氨基酸。这些化合物的制备产率为23–57%(相对于N-甲基α-氨基酸)。在第二种方法中,可以通过Arndt–Eistert方法将12个N保护的α-氨基酸直接同源,然后将所得的β-氨基酸以30–45%的产率转化为1,3-恶二嗪-6-酮。 。最后,还原裂解以41–63%的收率提供了所需的N-甲基β-氨基酸。