Preparative Isolation and Separation Procedure for Ginkgolides A, B, C, and J and Bilobalide

A simple preparative method for the isolation and purification of ginkgolides A, B, C, and J and bilobalide (ginkgo terpene trilactones) was developed. As starting material, a commercially available leaf extract from Ginkgo biloba containing ≥ 6% ginkgo terpene trilactones was used. After a partition step with EtOAc, the enriched intermediate extract was separated into the individual terpenes by medium-pressure liquid chromatography on silica impregnated with 6.5% NaOAc with a gradient from petroleum ether−EtOAc to EtOAc−MeOH. After recrystallization from H 2 O−MeOH, all five terpenes could be isolated in high purity. After a selective extraction with H 2 O, leaves could also be used as a starting material.