Synthetic studies of himbacine, a potent antagonist of the muscarinic M2 subtype receptor 1. Stereoselective total synthesis and antagonistic activity of enantiomeric pairs of himbacine and (2′S,6′R)-diepihimbacine, 4-epihimbacine, and novel himbacine congeners
Total synthesis of an enantiomeric pair of himbacine 1 and ent-1 was achieved in a highly stereoselective manner by employing an intermolecular Diels–Alder reaction of tetrahydroisobenzofuran 8 with chiral furan-2(5H)-one (S)-9 and (R)-9, respectively, as a key step. An enantiomeric pair of (2′S,6′R)-diepihimbacine 24 and ent-24, 4-epihimbacine 4-epi-1, and novel himbacine congeners bearing the same
Hydronaphtho[2,3-c]furan derivatives and process for the preparation thereof
申请人:Sagami Chemical Reasearch Center
公开号:US06392059B1
公开(公告)日:2002-05-21
Intermediates for the preparation of himbacine exhibiting muscarinic M2 receptor antagonism, which are hydronaphtho[2,3-c]furan derivatives represented by general formula (1) or intermediates for the preparation thereof:
wherein R1 is lower alkyl or aralky; R2 is hydrogen, lower alkyl or aralkyl; R3 and R4 together represent oxygen or methylene, or alternatively R4 is hydroxyl, lower alkoxy, aralkyloxy or lower acyloxy, with R3 being hydrogen; R5 and R6 together represent oxygen, or alternatively R6 is hydroxyl, lower alkxy, aralkyloxy or lower acyloxy, with R5 being hydrogen; and either of the broken lines is a single bond and the other thereof is a double bond, or alternatively both are single bonds.
HYDRONAPHTHO 2,3-c]FURAN DERIVATIVES AND PROCESS FOR THE PREPARATION THEREOF
申请人:SAGAMI CHEMICAL RESEARCH CENTER
公开号:EP1138679A1
公开(公告)日:2001-10-04
The invention provides useful intermediates for preparing himbacine, being an alkaloid with potent and selective antagonism against muscarine M2 receptor.
Hydronaphtho[2,3-c]furan derivatives represented by a following general formula (1)
(wherein R1 denotes a lower alkyl group or substituted or unsubstituted aralkyl group, R2 denotes a hydrogen atom, lower alkyl group or substituted or unsubstituted aralkyl group, R3 and R4 unitedly denote an oxygen atom or methylene group, or R3 denotes a'hydrogen atom and R4 denotes a hydroxyl group, lower alkoxy group, substituted or unsubstituted aralkyloxy group or lower acyloxy group, R5 and R6 unitedly denote an oxygen atom, or R5 denotes a hydrogen atom and R6 denotes a hydroxyl group, lower alkoxy group, substituted or unsubstituted aralkyloxy group or lower acyloxy group, and, in the case of broken lines accompanied, one denotes single bond and the other denotes double bond, or both denote single bonds), and their intermediates.