Molecular rearrangements in derivatives of grandiflorenic acid [(-)-kaur-9(11),16-dien-19-oic acid]
Year: 1994
Type: article
Abstract: Seven new skeletal diterpenes, 4,6,8,9,11,13 and 14, were obtained via the rearrangements of lb,c, 3,10a,b,c and 12, the derivatives of la, and the structures and stereochemistries of these compounds and also the mechanisms for their formation iire described.The objective of this work is to study the rearrangements in the derivatives of grandiflorenic acid la [(-)-kaur-9(11),16-dien-19-oic acid] in order to construct diterpenes with new ring systems.Our initial investigation aimed to transform la to the analogs of zoapatlin 2a (l), eupatalbin 2b, or eupatoralbin 2c (2).We fiist investigated this possibility via the rearrangements of the 9.1 1-epoxide of methyl (-)-kaur-9(1 l)-en-19-oate lb.Epoxidation of l b with MCPBA took place stereoselectively at the more accesible a-side and yielded exclusively 9, 1 la-epoxide 3.During this epoxidation we observed that when l b contained N-nitrosomethylurea as an impurity, the expected 3 was not obtained, but instead 4 was isolated.
Source: Pure and Applied Chemistry
Institution: Instituto Venezolano de Investigaciones Científicas
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W1991972035