Premium
Regiochemistry‐Directed Syntheses of Polyhydroxylated Alkaloids from Chiral Aziridines
Author(s) -
Eum Heesung,
Choi Jihye,
Cho CheonGyu,
Ha HyunJoon
Publication year - 2015
Publication title -
asian journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.846
H-Index - 44
eISSN - 2193-5815
pISSN - 2193-5807
DOI - 10.1002/ajoc.201500285
Subject(s) - indolizidine , chemistry , regioselectivity , aziridine , stereoselectivity , pyrrolizidine , dihydroxylation , stereochemistry , stereocenter , castanospermine , enantioselective synthesis , reductive amination , ring (chemistry) , bicyclic molecule , organic chemistry , alkaloid , enzyme , catalysis
In this study, two possible regiochemical pathways of aziridine ring opening, termed “regiochemistry‐directed branches for 2‐substituted aziridines” are described, providing easy access to two classes of compound from a common synthetic intermediate. Application of this synthetic strategy, with stereoselective dihydroxylation and reductive amination as the key steps, allowed the asymmetric synthesis of natural and unnatural polyhydroxylated alkaloids including the calyculin fragment C 33 –C 37 , 1,4‐dideoxy‐1,4‐imino‐ l ‐ribitol and analogues of hyacinthacine, swainsonine, castanospermine, and deoxynojirimycin. The initial domino reactions consisted of aziridine ring opening and debenzylation, and reductive double annulations were established for the preparation of bicyclic pyrrolizidine and indolizidine—represented by 8‐deoxyhyacinthacine and (3 R )‐methyl‐8‐deoxyswainsonine—with remarkable stereoselectivity and in high yield.