Concise and divergent total synthesis of swainsonine, 7-alkyl swainsonines, and 2,8a-diepilentiginosine via a chiral heterocyclic enaminoester intermediate
The concise and divergenttotalsyntheses of (−)-swainsonine, (−)-7-alkyl swainsonines, and (−)-2,8a-diepilentiginosine from a common chiral heterocyclic enaminoester intermediate in five-step sequences are presented. The highly efficient annulation reaction of the chiral heterocyclic enaminoester with various α,β-unsaturated carboxylates, and a straightforward carboxy inversion constituted the key
The intramolecular cycloaddition of azides with ω-chloroalkenes. A facile route to (±)-swainsonine and other indolizidine alkaloids
作者:William H. Pearson、Ko-Chung Lin
DOI:10.1016/s0040-4039(00)97301-5
日期:1990.1
A potentially generalroute to the 1-azabicyclo[n.m.O]alkane skeleton of various alkaloids is embodied in the intramolecular 1,3-dipolar cycloaddition of aliphatic azides with ω-chloroalkenes. Cycloaddition is followed by rearrangement and intramolecular N-alkylation, affording bicyclic iminium ions1 in one operation. The application of this method to the synthesis of (±)-δ-coniceine6, (1S,2R,8aR)-indolizidine-1
Stereoisomeric Sugar-Derived Indolizines as Versatile Building Blocks: Synthesis of Enantiopure Di- and Tetrahydroxyindolizidines
作者:Claudio Paolucci、Lucia Mattioli
DOI:10.1021/jo0016428
日期:2001.7.1
The synthesis of the sugar-derived (1S,2R,8aR)-1,2-di-O-isopropylidene-1,2,3,5,6,8a-hexahydro-5- oxoindolizine (8) and by analogy of the corresponding stereoisomers ent-8 and ent-7, an epimer at C-2 of ent-8, has been accomplished in a straightforward manner. The carbon-carbon double bond and the carbonyl functionalities on the six-membered ring make these nitrogen-containing heterocycles useful building blocks for the efficient preparation of a variety of enantiopure polyhydroxylated indolizidines of interest for their glycosidase inhibitory activity. We report here the synthesis of 2,8a-diepilentiginosine 12 from 8 and the preparation of stereoisomeric 1,2,7,8-tetrahydroxyindolizidines 9-11 performed by OsO4-catalyzed double bond syn dihydroxylation of 7 and 8, followed by deoxygenation of the amide group.
PEARSON, WILLIAM H.;LIN, KO-CHUNG, TETRAHEDRON LETT., 31,(1990) N2, C. 7571-7574
作者:PEARSON, WILLIAM H.、LIN, KO-CHUNG
DOI:——
日期:——
COLEGATE, S. M.;DORLING, P. R.;HUXTABLE, C. R., AUSTRAL. J. CHEM., 1984, 37, N 7, 1503-1509