The influence of the functional groups present in the glycosyl donor on the stereoselective glycosylation of 2‐azido‐2‐deoxy sugar thioglycosides under the N‐iodosuccinimide (NIS) and triflic acid (TfOH) mediated glycosylation conditions has b...
http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
https://www.riss.kr/link?id=O112845522
2020년
-
1434-193X
1099-0690
SCI;SCIE;SCOPUS
학술저널
3398-3409 [※수록면이 p5 이하이면, Review, Columns, Editor's Note, Abstract 등일 경우가 있습니다.]
0
상세조회0
다운로드다국어 초록 (Multilingual Abstract)
The influence of the functional groups present in the glycosyl donor on the stereoselective glycosylation of 2‐azido‐2‐deoxy sugar thioglycosides under the N‐iodosuccinimide (NIS) and triflic acid (TfOH) mediated glycosylation conditions has b...
The influence of the functional groups present in the glycosyl donor on the stereoselective glycosylation of 2‐azido‐2‐deoxy sugar thioglycosides under the N‐iodosuccinimide (NIS) and triflic acid (TfOH) mediated glycosylation conditions has been studied in detail. It was observed that beta glycosides of 2‐azido‐2‐deoxy sugar are formed mainly via a stable alpha‐glycosyl triflate intermediate followed by SN2 substitution of the triflate group by the acceptor. The presence of an electron withdrawing functional group such as O‐picoloyl (Pico) in the glycosyl donor facilitates the formation of stable α‐glycosyl triflate to furnish β‐glycosides, whereas the presence of an electron donating hydrogen bond mediating functional group such as p‐methoxybenzyl (PMB) in the glycosyl donor directs the formation of 1,2‐cis glycosides via the glycosyl oxycarbenium ion intermediate with B2,5 and 4H3 conformation. Excellent yields of the β‐glycosides were obtained in case of 2‐azido‐2‐deoxy‐d‐mannose and 2‐azido‐2‐deoxy‐d‐galactose thioglycosides, and 2‐azido‐2‐deoxy‐d‐glucose thioglycosides furnish moderate yields of the β‐glycosides.
A detailed study is reported on the influence of the functional groups present in the glycosyl donor towards the stereoselective glycosylation of 2‐azido‐2‐deoxy sugar thioglycosides under the N‐iodosuccinimide (NIS) and TfOH mediated glycosylation conditions.
Front Cover: Aliphatic α‐Boryl‐α‐bromoketones: Synthesis and Reactivity (Eur. J. Org. Chem. 23/2020)
Supramolecular Catalysts Featuring Crown Ethers as Recognition Units