Enantioselective Synthesis of Poison-Frog Alkaloid 237D and Determination of Absolute Stereochemistry
作者:Naoki Toyooka、Hideo Nemoto、Masashi Kawasaki、John W. Daly、Thomas F. Spande、H. Martin Garraffo
DOI:10.3987/com-04-10269
日期:——
An enantioselective synthesis of the 5-heptyl-8-methylindolizidine ((-)7) has been achieved. Alkaloid ((-)-7, (MW 237)) was used to determine the relative and absolute stereochemistry of the natural indolizidine 237D from frog skin as 5S, 8S, 9R using GC-IR and GC-MS. Chiral gas-chromatographic comparisons with catalytically reduced (+)-235B" and (-)-235B' indicated (-)-7 had the same absolute stereochemistry as the dihydro-product resulting from (-)-23513' and is naturally occurring in certain extracts of Panamanian poison frogs (Dendrobates).