Furo[2',3',4':3,4]indeno[1,2-b:6,7-b']bis[1]benzopyran-5b,7(5H)-dicarboxylic acid, 7,7a,7b,8,14,14b-hexahydro-4,7,13-trihydroxy-2,11-dimethyl-5,14-dioxo-, dimethyl ester, (5bS,7S,7aR,7bR,14bS)-

Remisporine B is a polyketide and derivative of remisporine A that has been found in Penicillium and has immunosuppressant activity.1,2 It inhibits LPS- or concanavalin A-induced proliferation of isolated mouse splenic lymphocytes (IC50s = 30.1 and 32.4 μg/ml, respectively).1

1.Liu, H., Chen, S., Liu, W., et al.Polyketides with immunosuppressive activities from mangrove endophytic fungus Penicillium sp. ZJ-SY2Mar. Drugs14(12)217(2016) 2.Kong, F., and Carter, G.T.Remisporine B, a novel dimeric chromenone derived from spontaneous Diels-Alder reaction of remisporine ATetrahedron Lett.44(15)3119-3122(2003)