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Total Synthesis and Stereochemical Assignment of Nostosin B.

ABSTRACT: Nostosins A and B were isolated from a hydrophilic extract of Nostoc sp. strain from Iran, which exhibits excellent tryps inhibitory activity. Nostosin A was the most potent natural tripeptide aldehyde as trypsin inhibitor up to now. Both R- and S-2-hydroxy-4-(4-hydroxy-phenyl) butanoic acid (Hhpba) were prepared and incorporated into the total synthesis of nostosin B, respectively. Careful comparison of the NMR spectra and optical rotation data of synthetic nostosin B (1a and 1b) with the natural product led to the unambiguous identification of the R-configuration of the Hhpba fragment, which was further confirmed by co-injection with the authentic sample on HPLC using both reversed phase column and the chiral AD-RH column.

SUBMITTER: Wang X

PROVIDER: S-EPMC5367015 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Total Synthesis and Stereochemical Assignment of Nostosin B.

Wang Xiaoji X Feng Junmin J Xu Zhengshuang Z Ye Tao T Meng Yi Y Zhang Zhiyu Z

Marine drugs 20170227 3

Nostosins A and B were isolated from a hydrophilic extract of Nostoc sp. strain from Iran, which exhibits excellent tryps inhibitory activity. Nostosin A was the most potent natural tripeptide aldehyde as trypsin inhibitor up to now. Both R- and S-2-hydroxy-4-(4-hydroxy-phenyl) butanoic acid (Hhpba) were prepared and incorporated into the total synthesis of nostosin B, respectively. Careful comparison of the NMR spectra and optical rotation data of synthetic nostosin B (1a and 1b) with the natur ...[more]

PMID: 28264450

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