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Asymmetric Synthesis of the C15?C32 Fragment of Alotamide and Determination of the Relative Stereochemistry.

ABSTRACT: Alotamide is a cyclic depsipetide isolated from a marine cyanobacterium and possesses a unique activation of calcium influx in murine cerebrocortical neurons (EC₅₀ 4.18 µM). Due to its limited source, the three stereocenters (C19, C28, and C30) in its polyketide fragment remain undetermined. In this study, the first asymmetric synthesis of its polyketide fragment was achieved. Four relative possible diastereomers were constructed with a boron-mediated enantioselective aldol reaction and Julia?Kocienski olefination as the key steps. Comparison of ¹³C NMR spectra revealed the relative structure of fragment C15?C32 of alotamide.

SUBMITTER: Shi HY

PROVIDER: S-EPMC6266257 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Asymmetric Synthesis of the C15⁻C32 Fragment of Alotamide and Determination of the Relative Stereochemistry.

Shi Hao-Yun HY Xie Yang Y Hu Pei P Guo Zi-Qiong ZQ Lu Yi-Hong YH Gao Yu Y Huang Cheng-Gang CG

Marine drugs 20181030 11

Alotamide is a cyclic depsipetide isolated from a marine cyanobacterium and possesses a unique activation of calcium influx in murine cerebrocortical neurons (EC<sub>50</sub> 4.18 µM). Due to its limited source, the three stereocenters (C19, C28, and C30) in its polyketide fragment remain undetermined. In this study, the first asymmetric synthesis of its polyketide fragment was achieved. Four relative possible diastereomers were constructed with a boron-mediated enantioselective aldol reaction a ...[more]

PMID: 30380702

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