81076-53-1Relevant academic research and scientific papers
A short and modular approach towards 3,5-disubstituted indolizidine alkaloids
Nebe, Marco M.,Zinn, Sina,Opatz, Till
, p. 7084 - 7091 (2016/07/30)
3,5-Dialkyl indolizidines have been prepared in four linear steps from commercially available starting materials. The sequence involves two direct α-functionalization steps and a subsequent reductive amination and provides diastereoselective access to both C-3 epimers of the 5,9-trans-substituted indolizines. The naturally occurring indolizidines 195B and 223AB have been synthesized using this methodology.
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 (2007/10/02)
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.
Rearrangement of Isoxazoline-5-spiro Derivatives. 5. Diastereofacial Selectivity in the Cycloaddition of Substituted Five-Membered Cyclic Nitrones and Methylenecyclopropanes. Srereoselective Synthesis of 3,5-Substituted Indolizidinones
Cordero, Franca M.,Brandi, Alberto,Querci, Cecilia,Goti, Andrea,Sarlo, Francesco De,Guarna, Antonio
, p. 1762 - 1767 (2007/10/02)
Substituted five-membered cyclic nitrones 1-3 cycloadd to substituted methylenecyclopropanes 4 and 5 with high diasrereofacial selectivity, through anti-anti transition states, to produce regioisomeric hexahydrospirocyclopropane-1,2'(and 3')-pyrrolo1.2-
AN INTRAMOLECULAR RING CONTRACTION APPROACH TO THE SYNTHESIS OF INDOLIZIDINE ALKALOIDS
Zeller, Emmanuel,Grierson, David S.
, p. 1575 - 1578 (2007/10/02)
Reaction of the anion of synthon 5 with PrBr followed by reductive decyanation gave the key intermediate 8.Ring opening of 8, on treatment with diethyl cyanophosphonate, produced 9.Compound 9 reacted with K plus 18-crown-6 in THF to give a 9:1 mixture of indolizidines 10 and 11.
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.
