Rh-Catalyzed C-C Bond Activation For Total Synthesis Of Ergot Alkaloids

Ergot alkaloids are several important natural toxins and drugs in human history.It was first known because of the spread of diseases such as rye and a wide range of diseases.With the development of science and technology,people have a deep understanding of ergot alkaloids and found that it has a good pharmacological effect,which has therapeutic effects on promoting production,inhibiting postpartum hemorrhage,cardiovascular and nervous system.It can be seen from the structure that the lysergic acid family is a 3,4-poly anthracene ring structure which exists in many important natural products.Due to the good biological activity of ergot alkaloids and its unique structure,many research groups around the world have been attracted to complete the synthesis of this family.Xylanigripones A is a special type of structure in alkaloids with a completely aromatized tetracyclic structure that is isolated in the ginseng.Wuling Ginseng is a valuable Chinese herbal medicine in China.It has anti-insomnia,sedative and other neurological pharmacological effects.However,due to the special environment and living conditions of Wuling Ginseng,it is not easy to separate and extract,which makes it not widely used in medicine.During treatment.Because Xylanigripones A and other lysergic acid family molecules have important biological activities,they are of great significance for their research.In this paper,the method of carbon-carbon bond activation is used to complete the synthesis of the tricyclic core skeleton of this kind of natural product.On this basis,the complete synthesis of the natural product Xylanigripones A was completed in a simple and rapid manner by simple functional group modification and transformation.Specific steps include: carbon-carbon bond activation of the synthesis of the precursor benzotetrahydrone.The catalytic system is screened,including catalysts,ligands,solvents and temperatures,construction of pyridine rings,and the like.The paper provides a new idea for the synthesis of ergot alkaloid Xylanigripones A,which has important reference significance for the synthesis of other members of the ergot ergot family.