Evidence of robust participation by an equatorial 4-O group in glycosylation on a 2-azido-2-deoxy-glucopyranosyl donorElectronic supplementary information (ESI) available: Experimental details and NMR spectra of new compounds. See DOI: 10.1039/c7cc00274b

• Main Authors: Yao, Dongming, Liu, Yichu, Yan, Shiqiang, Li, Yingxia, Hu, Chun, Ding, Ning
• Format: Article
• Language: English
• ISSN: 1359-7345; 1364-548X
• DOI: 10.1039/c7cc00274b

Although there are numerous claims of remote group participation leading to the synthesis of the expected glycosides with improved anomeric geometry outcome in glycosylation, there is still a lack of enough strong evidence and this has led to a long-term debate, particularly for equatorial 4- O group participation. In this work, we were able to synthesize and isolate a stable seven-membered trichlorooxazepine ring bridging intermediate with a high yield by employing a 2-azido-2-deoxy-glucopyranosyl donor, which provides strong evidence to support the putative participation of the equatorial 4- O group in glycosylation. An isolated bridging intermediate as evidence of equatorial 4- O group participation in glycosylation.