Synthesis of N-trifluoroacetyl-l-acosamine, N-trifluoroacetyl-l-daunosamine, and their 1-thio analogs
作者:István Pelyvás、Akira Hasegawa、Roy L. Whistler
DOI:10.1016/0008-6215(86)85039-x
日期:1986.2
A simple and efficient route to N-trifluoroacetyl-L-acosamine (13), N-trifluoroacetyl-L-daunosamine (12), and their 1-thio analogues (18 and 20) is described. Stereoselective reduction of oxime 5 with borane, followed by trifluoroacetylation resulted in the arabino methyl glycoside (8), which, on mild acid hydrolysis gave N-trifluoroacetyl-L-acosamine (13) in an overall yield of 33%, based on L-rhamnal
描述了一种简单而有效的途径来制备N-三氟乙酰基-L-花生胺(13),N-三氟乙酰基-L-豆胺(12)及其1-硫代类似物(18和20)。用硼烷对肟5进行立体选择性还原,然后进行三氟乙酰化,生成阿拉伯糖甲基糖苷(8),经轻度酸水解后,得到的N-三氟乙酰基-L-花生四烯胺(13)的总收率为33%,基于L-隆鼻(1)。在氧化C-4羟基并立体选择性还原生成的酮11后,将L-阿拉伯糖构型的化合物8以一烧瓶顺序转化为N-三氟乙酰基-L-柔红胺(12),总产率为28以1为单位计算%。苯甲硫醇的迈克尔型加成反应由烯酮2合成1-苄基1-硫代-N-三氟乙酰基-α-L--胺(18),然后进行肟化,用硼烷进行立体选择性还原,然后进行三氟乙酰化。通过相应的糖基氯衍生物从12制备4-O-乙酰基-1-S-乙酰基-N-三氟乙酰基-1-硫代-β-L-柔红胺20。