A green and efficient photolabile protecting group(PPG)-mediated glycosidation approach for the synthesis of 2-deoxy-glycosides is reported.By employing ortho-nitrobenzyl carbonate(oNBC)as PPG,N,N-dimethylformamide(DM...A green and efficient photolabile protecting group(PPG)-mediated glycosidation approach for the synthesis of 2-deoxy-glycosides is reported.By employing ortho-nitrobenzyl carbonate(oNBC)as PPG,N,N-dimethylformamide(DMF)-modulated SPhosAuNTf_(2)-promoted glycosidation with per-oNBC-protected 2-deoxy-glycosyl ynenoates affords the 2-deoxy-glycosides with moderate to excellentα-selectivities presumably depending on the reactivities of the acceptor alcohols.Based on the PPG-mediated glycosidation approach,oligosaccharides with three to six oNBC groups are effectively achieved.The multiple oNBC groups in the 2-deoxy-glycosides are completely cleaved by irradiation at 365 nm,resulting in the desired 2-deoxy-glycosides in an efficient manner without affecting the common alkyne,alkene,azide functional groups and the traditional protecting groups on the aglycones.展开更多
基金Financial support from the National Natural Science Foundation of China(21871081,22071054)the Fundamental Research Funds for the Central Universities(50321031916002,22221818014)is gratefully acknowledged.
文摘A green and efficient photolabile protecting group(PPG)-mediated glycosidation approach for the synthesis of 2-deoxy-glycosides is reported.By employing ortho-nitrobenzyl carbonate(oNBC)as PPG,N,N-dimethylformamide(DMF)-modulated SPhosAuNTf_(2)-promoted glycosidation with per-oNBC-protected 2-deoxy-glycosyl ynenoates affords the 2-deoxy-glycosides with moderate to excellentα-selectivities presumably depending on the reactivities of the acceptor alcohols.Based on the PPG-mediated glycosidation approach,oligosaccharides with three to six oNBC groups are effectively achieved.The multiple oNBC groups in the 2-deoxy-glycosides are completely cleaved by irradiation at 365 nm,resulting in the desired 2-deoxy-glycosides in an efficient manner without affecting the common alkyne,alkene,azide functional groups and the traditional protecting groups on the aglycones.