title: Divergent total synthesis of 1,6,8a-tri-epi-castanospermine and 1-deoxy-6,8a-di-epi-castanospermine from substituted azetidin-2-one (β-lactam), involving a cascade sequence of reactions as a key step.
abstract: A divergent, short, and novel total synthesis of 1,6,8a-tri-epi-castanospermine (7) and 1-deoxy-6,8a-di-epi-castanospermine (8) has been developed via a common precursor, 15, obtained from D-mannitol derived β-lactam. The key step involves a one pot cascade sequence of trimethyl sulfoxonium ylide based cyclization of epoxy sulfonamide 14via epoxide ring opening, one carbon homologation followed by intramolecular cyclization.
authors.affiliation: Division of Inorganic and Physical Chemistry Division, Indian Institute of Chemical Technology, Tarnaka, Hyderabad-500007, India. dktiwari@iict.res.in dkt80.org@gmail.com.
authors.forename: Dipak Kumar
authors.initials: DK
authors.lastname: Tiwari
authors.forename: Kishor Chandra
authors.initials: KC
authors.lastname: Bharadwaj
authors.forename: Vedavati G
authors.initials: VG
authors.lastname: Puranik
authors.forename: Dharmendra Kumar
authors.initials: DK
authors.lastname: Tiwari
mesh_terms: D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D054836:Indolizidines / Q000138:chemical synthesis* / Q000737:chemistry; D007212:Indolizines / Q000138:chemical synthesis* / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D013237:Stereoisomerism; D047090:beta-Lactams / Q000737:chemistry*
chemical_list: D000470:Alkaloids; D054836:Indolizidines; D007212:Indolizines; D047090:beta-Lactams; C065905:1-deoxycastanospermine