A concise and stereoselective synthesis of α-galactosylceramide (α-GalCer) is described. The key features of the synthetic strategy are the use of a phytosphingosine in which the amine is masked as a tetrachlorophthalimide and the diol as an isopropylidene acetal, and the galactosyl donor is protected as a 4,6-benzylidene to improve the α selectivity of the glycosylation reaction. The pattern of protecting groups on the donor and the acceptor have proven to give an excellent match of reactivity, allowing the glycosylation reaction to take place stereoselectively. The overall synthesis gave α-GalCer in good yields and in few steps.

中文翻译：

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一种高效简洁的α-半乳糖神经酰胺合成方法

描述了 α-半乳糖神经酰胺 (α-GalCer) 的简洁立体选择性合成。合成策略的关键特征是使用植物鞘氨醇，其中胺被掩蔽为四氯邻苯二甲酰亚胺，二醇被掩蔽为异丙叉缩醛，半乳糖基供体被保护为 4,6-亚苄基以提高α选择性糖基化反应。供体和受体上的保护基团模式已被证明提供了极好的反应性匹配，允许立体选择性地进行糖基化反应。整个合成以良好的收率和几个步骤得到 α-GalCer。