华东理工大学杨友团队报道了光不稳定的邻硝基碳酸苄作为永久羟基保护基，用于合成双半乳糖二酰基甘油。相关研究成果发表在2024年10月16日出版的《中国化学》。

传统的保护基团通常在恶劣条件下用潜在危险的试剂去除，从而阻碍了低聚糖和糖苷的方便合成。

该文中，研究人员提出利用光不稳定的邻硝基苄基碳酸酯（oNBC）作为永久羟基保护基团，用于糖苷的立体控制合成。

Ph3PO通过强解除全-O-oNBC保护的糖基炔酸酯调节糖基化，优选通过β-鏻过渡态提供具有优异α选择性的糖苷。

基于oNBC介导的半乳糖基化，以简单的方式合成了含有六个双键和两个酯的糖脂二半乳糖基二酰基甘油（DGDG）。

附：英文原文

Title: Photolabile ortho-Nitro-Benzyl Carbonate as a Permanent Hydroxyl Protecting Group for the Synthesis of Digalactosyl Diacylglycerol

Author: Jibin Zheng, Hongyu Chen, Jintao Shang, Lvfeng Zhang, Youling Liang, Dongsheng Chang, You Yang

Issue&Volume: 2024-10-16

Abstract: Traditional protecting groups are often removed under harsh conditions with potentially hazardous reagents, thereby impeding the convenient synthesis of oligosaccharides and glycosides. Herein, we present to utilize the photolabile ortho-nitro-benzyl carbonate (oNBC) as a permanent hydroxyl protecting group for stereocontrolled synthesis of glycosides. The Ph3PO-modulated glycosylation with strongly disarmed per-O-oNBC-protected glycosyl ynenoates preferred to afford glycosides with excellent α-selectivities via the β-phosphonium transition state. Based on the oNBC-mediated galactosylation, synthesis of the glycolipid digalactosyl diacylglycerol (DGDG) containing six double bonds and two esters was achieved in a straightforward manner.

DOI: 10.1002/cjoc.202400866

Source: https://onlinelibrary.wiley.com/doi/full/10.1002/cjoc.202400866