Immunosuppressive Sesquiterpenoids from the Edible Mushroom Craterellus odoratus .

The aim of this work was to comprehensively understand the chemical constituents of the edible mushroom Craterellus ordoratus and their bioactivity. A chemical investigation on this mushroom led to the isolation of 23 sesquiterpenoids including eighteen previously undescribed bergamotane sesquiterpenes, craterodoratins A-R ( 1 - 18 ), and one new victoxinine derivative, craterodoratin S ( 19 ). The new structures were elucidated by detailed interpretation of spectrometric data, theoretical nuclear magnetic resonance (NMR) and electronic circular dichroism (ECD) calculations, and single-crystal X-ray crystallographic analysis. Compounds 1 and 2 possess a ring-rearranged carbon skeleton. Compounds 3 , 10 , 12 - 15 , 19 , 20 and 23 exhibit potent inhibitory activity against the lipopolysaccharide (LPS)-induced proliferation of B lymphocyte cells with the IC 50 values ranging from 0.67 to 22.68 μM. Compounds 17 and 20 inhibit the concanavalin A (ConA)-induced proliferation of T lymphocyte cell with IC 50 values of 31.50 and 0.98 μM, respectively. It is suggested that C. ordoratus is a good source for bergamotane sesquiterpenoids, and their immunosuppressive activity was reported for the first time. This research is conducive to the further development and utilization of C. ordoratus .