Arteether , its cas register number is 75887-54-6. It also can be called (3R,5aS,6R,8aS,9R,10S,12R,12aR)-10-Ethoxydecahydro-3,6,9-trimethyl-3,12-epoxy-12H-pyrano(4,3-j)-1,2-benzodioxepin ; Artemotil ; Dihydroartemisinin ethyl ether ; 3,12-Epoxy-12H-pyrano(4,3-j)-1,2-benzodioxepin, 10-ethoxydecahydro-3,6,9-trimethyl-, (3S-(3alpha,5alpha,6alpha,8aalpha,9beta,10beta,12beta,12aalpha))- ; 3,12-Epoxy-12H-pyrano(4,3-j)-1,2-benzodioxepin, decahydro-10-ethoxy-3,6,9-trimethyl-, (3R-(3alpha,5abeta,6beta,8abeta,9alpha,10alpha,12beta,12aR*))- . It is a white crystalline solid.