Diels-Alder approaches to pentacyclic triterpenes of the arborane and the fernane families
摘要:
The high pressure Diels-Alder reaction of diene 2 and ene-dione 3 does not lead to the arborane skeleton but to angular isomers 5. The AB + D synthesis of tetracyclic ene-dione 6, followed by construction of the E-ring by a double alkylation, yields the isoarborinol precursor 7; the fernane series is similarly accessed.
Diels-Alder approaches to pentacyclic triterpenes of the arborane and the fernane families
摘要:
The high pressure Diels-Alder reaction of diene 2 and ene-dione 3 does not lead to the arborane skeleton but to angular isomers 5. The AB + D synthesis of tetracyclic ene-dione 6, followed by construction of the E-ring by a double alkylation, yields the isoarborinol precursor 7; the fernane series is similarly accessed.
Studies towards the total synthesis of pentacyclic triterpenes of the arborane and fernane family
作者:Simeon Arseniyadis、Ricardo Rodriguez、José Camara、Jean F. Gallard、Eric Guittet、Loïc Toupet、Guy Ourisson
DOI:10.1016/0040-4020(95)00530-l
日期:1995.1
Stereo and regrochemcal variations in conjugate addition reactions leading to isoarborinal and fernenol-Hke interpenes via a five-step protccol are described. The Gngnard addition on 9, 10, 15 and 18 served lo establish the relative stereoehemicul details.
The high pressure Diels-Alder reaction of diene 2 and ene-dione 3 does not lead to the arborane skeleton but to angular isomers 5. The AB + D synthesis of tetracyclic ene-dione 6, followed by construction of the E-ring by a double alkylation, yields the isoarborinol precursor 7; the fernane series is similarly accessed.