AIDS-223809 AIDS223809 Clausenolide-1 ethyl ether Furo[3',4':5,6]naphth[2,1-c]oxireno[d]pyran-5,7(3H,6aH)-dione, 1-ethoxy-9-(3-furanyl)decahydro-11-hydroxy-1,3,3,5a,9a,11b-hexamethyl-, (1S,3aR,5aR,5bR,6aS,9R,9aS,11S,11aR,11bR)-