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Synthesis of Solanum Alkaloid Demissidine Stereoisomers and Analogues
Juan A Rivas-Loaiza1, Aneta Baj1, Yliana López2
1Faculty of Chemistry, University of Białystok, Ciołkowskiego 1K, 15-245 Białystok, Poland.
Abstract:
Demissidine is an indolizidine alkaloid isolated from several potato species. A simple synthesis of demissidine stereoisomers and analogues from a common steroidal sapogenin tigogenin is presented in the paper. The key intermediate in the synthesis of these compounds is readily available tigogenoic acid. Its step-by-step transformation to indolizidine yielded 20R,25R or 20R,25S products while the direct reductive amination produced the 20S,25R compound (25-epi-demissidine).
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