title: The preparation of (-)-grandisine B from (+)-grandisine D; a biomimetic total synthesis or formation of an isolation artefact?
abstract: An efficient new alkyne-acetal cyclization procedure has been developed to prepare enantiopure indolizidine building blocks from l-proline and then applied to prepare the Elaeocarpus-derived alkaloids grandisine B and grandisine D in an efficient manner. However, evidence is presented which indicates that grandisine B does not occur naturally but is formed by reaction of grandisine D with ammonia during the extraction/purification process.
authors: Department of Chemistry, University of York, Heslington, York YO10 5DD, UK.
authors: James D
authors: JD
authors: Cuthbertson
authors: Andrew A
authors: AA
authors: Godfrey
authors: Richard J K
authors: RJ
authors: Taylor
mesh_terms: D040761:Biomimetic Materials / Q000138:chemical synthesis* / Q000302:isolation & purification; D003500:Cyclization; D007212:Indolizines / Q000138:chemical synthesis* / Q000302:isolation & purification; D008958:Models, Molecular; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D007212:Indolizines; C499761:grandisine B; C546802:grandisine D