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First Total Synthesis of 5'-O-?-d-Glucopyranosyl Tubercidin.

ABSTRACT: The first total synthesis of 5'-O-?-d-glucopyranosyl tubercidin was successfully developed. It is a structurally unique disaccharide 7-deazapurine nucleoside exhibiting fungicidal activity, and was isolated from blue-green algae. The total synthesis was accomplished in eight steps with 27% overall yield from commercially available 1-O-acetyl-2,3,5-tri-O-benzoyl-?-d-ribose. The key step involves stereoselective ?-O-glycosylation of the corresponding 7-bromo-6-chloro-2',3'-O-isopropylidene-?-d-tubercidin with 2,3,4,6-tetra-O-benzyl-glucopyranosyl trichloroacetimidate. All spectra are in accordance with the reported data for natural 5'-O-?-d-glucopyranosyl tubercidin. Meanwhile, 5'-O-?-d-glucopyranosyl tubercidin was also prepared using the same strategy.

SUBMITTER: Ouyang W

PROVIDER: S-EPMC7459636 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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First Total Synthesis of 5'-O-α-d-Glucopyranosyl Tubercidin.

Ouyang Wenliang W Huang Haiyang H Yang Ruchun R Ding Haixin H Xiao Qiang Q

Marine drugs 20200729 8

The first total synthesis of 5'-O-α-d-glucopyranosyl tubercidin was successfully developed. It is a structurally unique disaccharide 7-deazapurine nucleoside exhibiting fungicidal activity, and was isolated from blue-green algae. The total synthesis was accomplished in eight steps with 27% overall yield from commercially available 1-O-acetyl-2,3,5-tri-O-benzoyl-β-d-ribose. The key step involves stereoselective α-O-glycosylation of the corresponding 7-bromo-6-chloro-2' ...[more]

PMID: 32751067

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