Today, the value of the ginkgo biloba is being recognized by human beings step by step, especially its medicinal value. The extract of ginkgo biloba has been used at preventing and treating the disease of cardiovascular system and cerebrovascular system, and it has a miraculous effect. The flavonids and ginkgolides are the main components of the extract of ginkgo biloba. Up to now, the synthetic mechanism of the flavonids and ginkgolides is not very clear, so we can not prosecute man-made control. At presen...