Isolation of some immunosuppressive components from an ascomycete, Gelasinospora multiforis.

Five new components, named multiforisins A, B, C, D, and E, with immunosuppressive activity were isolated from an Ascomycete, Gelasinospora multiforis. Multiforisin A, the main immunosuppressive principle of this fungus, was deduced to be 5-formyl-3-(hydroxymethyl)-4-methoxy-6-(1E-propenyl)-alpha-pyrone. Multiforisins B, C, D, and E were also deduced to be alpha-pyrone derivatives related to multiforisin A. The IC50 values of multiforisins A, B, C, D, E, and dihydro multiforisin A were evaluated against proliferation of mouse spleen lymphocytes stimulated with concanavalin A and lipopolysaccharide.