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Investigations into the Manzamine Alkaloid Biosynthetic Hypothesis
Jack E Baldwin1, Timothy D W Claridge1, Andrew J Culshaw1
1The Dyson Perrins Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QY (UK), Fax: (+44) 1865-275-632.
Abstract:
The biomimetic synthesis of a pentacyclic alkaloid (keramaphidin B, 1), an intermediate in the biogenetic pathway to the manzamine alkaloids, has been achieved. Compound 1 was formed by an intramolecular Diels-Alder reaction of macrocycle 2 in buffer followed by reduction with NaBH4 . This reaction provides the first direct expeimental evidence for the authors' biosynthetic hypothesis.
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