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Minor and trace sterols in marine invertebrates 48. The isolation, structure elucidation and synthesis of 23(R),24(R)-methylenecholesterol.

✍ Scribed by John R. Proudfoot; Carl Djerassi

Publisher: Elsevier Science
Year: 1984
Tongue: French
Weight: 227 KB
Volume: 25
Category: Article
ISSN: 0040-4039
DOI: 10.1016/s0040-4039(01)81608-7

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✦ Synopsis

The isolation, structure determination and synthesis of 23{R),24{R)-methylene-:holesterol--a possible biosynthetic precursor of brassicasterol--is described.

We had earlier suggested that cyclopropylsterols may be biosynthetic intermediates in the alkylation of marine sterols 2 . In this communication we report the first isolation of ~3{R),24{R)-methylenecholesterol (1), a possible biosynthetic precursor of the naturally

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