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 greater than or equal to 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 H2O-MeOH, all five terpenes could be isolated in high purity. After a selective extraction with H2O, leaves could also be used as a starting material.