title: Asymmetric synthesis of (-)-7-epiaustraline and (+)-1,7-diepiaustraline.
abstract: A diastereoselective and modular approach to the synthesis of the 3-hydroxymethyl-2,3,5,6,7,7a-hexahydro-1H-pyrrolizine-1,2,7-triol structure, characteristic of several natural pyrrolizidine natural products, has been developed. This approach culminated in the synthesis of (-)-7-epiaustraline and (+)-1,7-diepiaustraline. The oxazolidinone group has been found to be a useful protecting group in the RCM reaction and, as part of a pyrrolo[1,2-c]oxazol-3-one ring system, has functioned as a stereo- and regio-directing group in a key diastereoselective cis-dihydroxylation reaction and a regioselective nucleophilic ring-opening of a S,S-dioxo-dioxathiole.
mesh_terms: D006900:Hydroxylation; D008958:Models, Molecular; D023303:Oxazolidinones / Q000737:chemistry; D011758:Pyrroles / Q000737:chemistry; D011763:Pyrrolizidine Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D023303:Oxazolidinones; D011758:Pyrroles; D011763:Pyrrolizidine Alkaloids; C412020:epiaustraline