Dimethylformamide-Modulated Kdo Glycosylation for Stereoselective Synthesis of α-Kdo Glycosides.

A simple and direct DMF-modulated α-selective Kdo glycosylation approach for the stereoselective synthesis of the α-linked Kdo glycosides is developed. Glycosylation of the readily available peracetylated Kdo ortho-hexynylbenzoate with common acceptor alcohols using SPhosAuNTf2 as a promoter and DMF as a modulating molecule afforded a range of Kdo glycosides with good α-selectivities. Furthermore, the present method is effectively applied in the latent-active synthesis of the α-linked di-Kdo glycoside bearing a linker at the reducing end. Finally, the first observation of a Kdo imidinium ion in the low-temperature NMR provides evidence for the plausible mechanism of the DMF-modulated α-selective Kdo glycosylation.

Citation

Qixin Lou, Qingting Hua, Liangliang Zhang, You Yang. Dimethylformamide-Modulated Kdo Glycosylation for Stereoselective Synthesis of α-Kdo Glycosides. Organic letters. 2020 Feb 07;22(3):981-985

Mesh Tags

Substances

PMID: 31917587

search → result