Studies on the terpenoids and related alicyclic compounds. XXIX. Chemical transformations of .ALPHA.-santonin into C-8 lactonized eudesmanolides: Telekin and pinnatifidin.
The chemical transformations of α-santonin (1), a C-6 lactonized eudesmanolide, into C-8 lactonized eudesmanolides, telekin (4) and pinnatifidin (5), are described. Desulfurization of the thio-ketal (8), derived from tetrahydroyomogin (7), with Raney Ni gave the 4-ene (10), which was converted into the α-epoxide (12). Ring-opening of the epoxy ring with LiNEt2 afforded the allyl alcohol (13). Phenylselenenylation of 13 gave the selenide (14), and oxidative elimination then gave telekin (4). Bromination of 3-oxoeudesman-8, 13-olide (18) gave the 2α-bromo-3-ketone (19). Reduction of 19 with NaBH4 gave bromohydrins (20 and 21), which were treated with Zn dust to afford the olefin (22). Treatment of 22 with N-bromosuccinimide afforded the 2-hydroxy-3-bromide (24), which was oxidized to give the 2-oxo-3-bromide (25). Dehydrobromination of 25 afforded the 2-oxo-3-ene (26). Pinnatifidin (5) was synthesized from 26 by phenylselenenylation and deselenoxylation procedures.
TRANSFORMATION OF ARTEMISIN INTO YOMOGIN AND 1-DEOXYIVANGUSTIN
作者:Manuel Arnó、Miguel Carda、J. Alberto Marco、Eliseo Seoane
DOI:10.1246/cl.1984.1021
日期:1984.6.5
Partial syntheses of the sesquiterpene lactones yomogin and 1-deoxyivangustin from artemisin are disclosed.
披露了来自青蒿的香酮倍半萜内酯yomogin和1-去氧伊万斯汀的部分合成。
MARCO, J. ALBERTO;CARDA, MIGUEL, TETRAHEDRON, 43,(1987) N 11, 2523-2532
作者:MARCO, J. ALBERTO、CARDA, MIGUEL
DOI:——
日期:——
Synthesis of umbellifolide and three natural eudesman-12,8-olides from (-)-artemisin
作者:J. Alberto Marco、Miguel Carda
DOI:10.1016/s0040-4020(01)81659-8
日期:——
Synthesis of yomogin, 1-deoxyivangustin, and 1-deoxy-8-epiivangustin
作者:Juan Alberto Marco、Manuel Arno、Miguel Carda
DOI:10.1139/v87-108
日期:1987.3.1
The chemical transformation of (−)-artemisin 1 into the natural sesquiterpene lactones yomogin 2, 1-deoxyivangustin 3, and 1-deoxy-8-epiivangustin 4 is described.