(7?)-7-Hydroxyginkgolide A; [1S-(1?,2?,3?,3aR*,4?,6a?,7a?,7b?,8?,10a?,11aR*)]-3-(1,1-Dimethylethyl)hexahydro-2,4,7b-trihydroxy-8-methyl-9H-1,7a-(Epoxymethano)-1H,6aH-cyclopenta[c]furo[2,3-b]furo[3',2':3,4]cyclopenta[1,2-d]furan-5,9,12(4H)-trione;BN 52024