Tetrahedron

An expeditious route to the synthesis of kelampayosides A and B

HI Duynstee, MC de Koning, GA van der Marel…

Index: Duynstee, Howard I.; De Koning, Martijn C.; Van der Marel, Gijs A.; Van Boom, Jacques H. Tetrahedron, 1999 , vol. 55, # 32 p. 9881 - 9898

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Citation Number: 16

Abstract

Chemoselective NIS/cat. TfOH-mediated glycosylation of ethyl2, 3, 4-tri-O-benzoyl-1-thio-β-d- glucopyranoside (13) with ethyl2, 3-di-O-acetyl-5-O-benzyl-1-thio-αβ-d-erythro- apiofuranoside (4a) gave dimer14 in an excellent yield. BF3• Et2O-catalysed condensation of the α-trichloroacetimidate31, accessible in two steps from14, with 3, 4, 5-trimethoxyphenol gave β-linked derivative32 followed by deprotection gave Kelampayoside A. Protecting ...