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Total Synthesis of the Proposed Structure of Paraphaeosphaeride C.

ABSTRACT: Paraphaeosphaeride C is a demethoxy derivative of phaeosphaeride A and exhibits STAT3 inhibitory activity. Our previous papers reported the total synthesis of phaeosphaeride A using a diastereoselective vinyl anion aldol reaction as the key step to construct the dihydropyran ring. In this work, the first total synthesis of the proposed structure of paraphaeosphaeride C was achieved via a similar synthetic strategy. The synthetic compound was characterized through extensive nuclear magnetic resonance (NMR) analysis but the 1H and 13C-NMR data for this compound did not correspond to those reported in the literature for paraphaeosphaeride C.

SUBMITTER: Kobayashi K

PROVIDER: S-EPMC6930451 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Total Synthesis of the Proposed Structure of Paraphaeosphaeride C.

Kobayashi Kenichi K Kunimura Risako R Kogen Hiroshi H

Molecules (Basel, Switzerland) 20191121 23

Paraphaeosphaeride C is a demethoxy derivative of phaeosphaeride A and exhibits STAT3 inhibitory activity. Our previous papers reported the total synthesis of phaeosphaeride A using a diastereoselective vinyl anion aldol reaction as the key step to construct the dihydropyran ring. In this work, the first total synthesis of the proposed structure of paraphaeosphaeride C was achieved via a similar synthetic strategy. The synthetic compound was characterized through extensive nuclear magnetic reson ...[more]

PMID: 31766322

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