First total synthesis of kipukasin A

Chuang Li; Haixin Ding; Zhizhong Ruan; Yirong Zhou; Qiang Xiao

doi:10.3762/bjoc.13.86

First total synthesis of kipukasin A

Beilstein J Org Chem. 2017 May 9:13:855-862. doi: 10.3762/bjoc.13.86. eCollection 2017.

Authors

Chuang Li¹, Haixin Ding¹, Zhizhong Ruan¹, Yirong Zhou¹, Qiang Xiao¹

Affiliation

¹ Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science & Technology Normal University, Nanchang, Jiangxi 330013, China.

Abstract

In this paper, a practical approach for the total synthesis of kipukasin A is presented with 22% overall yield by using tetra-O-acetyl-β-D-ribose as starting material. An improved iodine-promoted acetonide-forming reaction was developed to access 1,2-O-isopropylidene-α-D-ribofuranose. For the first time, ortho-alkynylbenzoate was used as protecting group for the 5-hydoxy group. After subsequent Vorbrüggen glycosylation, the protecting group could be removed smoothly in the presence of 5 mol % Ph₃PAuOTf in dichloromethane to provide kipukasin A in high yield and regioselectivity.

Keywords: Vorbrüggen glycosylation; gold catalysis; kipukasin A; marine nucleoside; total synthesis.