Crotaverric acid

Crotaverric acid is also a 8-lactone, obtained from crotaverrine (Table3Pii) by Suri etal 294). H-N.m.r. spectroscopy showed that crotaverric acid is diastereomeric with the 5-lactone of integerrinecic acid (72). Since lead tetraacetate oxidation of both diacids gave the same ketoacid, it was deduced that crotaverric acid has the opposite stereochemistry to (72) at either C-2 or C-3. 

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