A3I a3i (4S,4aS,6aR,8R,9R,10aS,13S,14aS,18aR,18bR,E)-9-ethyl-4,8,19-trihydroxy-10a,12,13,18a-tetramethyl-2,3,4,4a,6a,7,8,9,10,10a,13,14,18a,18b-tetradecahydro-14a,17-(metheno)benzo[b]naphtho[2,1-h][1]azacyclododecine-16,18(1H,15H)-dione A3I