(5aR,5bS,7aS,8R,10aS,10bR)-8-ethynyl-7a-methyl-2-oxo-2,3,4,5,5a,5b,6,7,7a,8,9,10,10a,10b,11,12-hexadecahydrocyclopenta[5,6]naphtho[1,2-d]azepin-8-yl acetate