Isolation of erinacine P, a new parental metabolite of cyathane-xylosides, from Hericium erinaceum and its biomimetic conversion into erinacines A and B

A new cyathane-xyloside, erinacine P, was isolated from mycelia of basidiomycetous Hericium erinaceum YB4-6237 in a shaken culture. Since its aglycon closely resembles typical cyathane diterpenoids such as cyathins and cyathatriols in its substitution pattern, this glycoside seems to be an important metabolite in the biosynthesis of erinacines and striatins. In fact, according to our biogenesis studies, erinacine P can be successfully converted chemically into erinacine B and, further, to erinacine A under mild conditions.