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Synthesis and structural reassignment of (+)-epicalyxin F.

ABSTRACT: We have established the structure of (+)-epicalyxin F through chemical synthesis. An acid-promoted rearrangement of synthetic benzopyran 6 led to the identification of the natural product as (3S,5S,7R)-epicalyxin F (22). Comparison with NMR spectra and optical rotation of the natural product confirms our assignment, and the reassigned structure is compatible with the proposed biosynthetic pathway.

SUBMITTER: Tian X

PROVIDER: S-EPMC2496922 | biostudies-other | 2007 Nov

REPOSITORIES: biostudies-other

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Synthesis and structural reassignment of (+)-epicalyxin F.

Tian Xia X Rychnovsky Scott D SD

Organic letters 20071025 24

We have established the structure of (+)-epicalyxin F through chemical synthesis. An acid-promoted rearrangement of synthetic benzopyran 6 led to the identification of the natural product as (3S,5S,7R)-epicalyxin F (22). Comparison with NMR spectra and optical rotation of the natural product confirms our assignment, and the reassigned structure is compatible with the proposed biosynthetic pathway. ...[more]

PMID: 17958435

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