Synthesis 2024; 56(07): 1147-1156
DOI: 10.1055/a-2183-0175
paper
Emerging Trends in Glycoscience

Expedient Synthesis of Superarmed Glycosyl Donors via Oxidative Thioglycosidation of Glycals

Nicholas P. Forsythe
,
Emma R. Mize
,
Gustavo A. Kashiwagi
,
A.V.D. thanks the National Institute of General Medical Sciences (GM111835) and the National Science Foundation (CHE-2147156) for support of this work. N.P.F. was supported by the National Institute of General Medical Sciences (T32, GM141602 grant).


Abstract

Superarmed glycosyl donors have higher reactivity compared to their perbenzylated armed counterparts. Generally, the 2-O-benzoyl-3,4,6-tri-O-benzyl protecting group pattern gives rise to increased reactivity due to an O-2/O-5 cooperative effect. Despite having a high reactivity profile and applicability in many expeditious strategies for glycan synthesis, regioselective introduction of the superarming protecting group pattern is tedious for most sugar series. Reported herein is a streamlined synthetic route to yield superarmed glycosyl donors of the d-gluco and d-galacto series equipped with an ethylthio, phenylthio, p-tolylthio, benzoxazol-2-ylthio, O-allyl, or O-pentenyl anomeric leaving group. This streamlined approach was made possible due to the refinement of the oxidative thioglycosylation reaction of the respective glucal and galactal precursors. The applicability of this approach to the direct formation of disaccharides is also showcased.

Supporting Information



Publication History

Received: 08 August 2023

Accepted after revision: 27 September 2023

Accepted Manuscript online:
27 September 2023

Article published online:
31 October 2023

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