96894-83-6Relevant academic research and scientific papers
General Entry to the 3,5-Disubstituted Indolizidine Class of Dendrobatid Alkaloids. Total Syntheses of Both Enantiomers of Indolizidines 195B, 223AB, 239AB, and 239CD from a Common Chiral Synthon
Machinaga, Nobuo,Kibayashi, Chihiro
, p. 5178 - 5189 (1992)
A general protocol for the total syntheses of both enantiomers of dendrobatid alkaloids, indolizidines 195B, 223AB, 239AB, and 239CD, belonging to the 3,5-disubstituted indolizidine subclass is described, in which 3,4-dideoxy-D-threo-hexitol (8) has been used as single and common chiral synthon.The syntheses of the (+)- and (-)-enantiomers of these alkaloids begin with (S,S)- and (R,R)-1,2:5,6-diepoxyhexanes (7), respectively, both of which were derived from 8 in three steps and are carried out by way of pyrrolidine formation via the cyclic sulfates leading to the(2R,5R)- and (2S,5S)-trans-2,5-dialkylated pyrrolidines, which were converted to the (+)- and (-)-enantiomers, respectively, of the title indolizidine alkaloids.These syntheses involve the first chiral preparations of indolizidines 239AB, 239CD both in natural (-)- and unnatural (+)-enantiomeric forms, which confirm the absolute configurations of natural 239AB and 239CD as 3R,5S,8aR and 3R,5R,8aR, respectively.
Indolizine Alkaloid Synthesis. Preparation of the Pharaoh Ant Trail Pheromone and Gephyrotoxin 223 Stereoisomers
Macdonald, Timothy L.
, p. 193 - 194 (2007/10/02)
A stereoselective entry into the 3,5-dialkylindolizidine alkaloid skeleton proceeding via N1-C2 vicinal annulation of a 1,4-dibromoalkane onto a pyrroline system is described.
