3-Ethyl-9,10-dimethoxy-2-(2-nitro-benzenesulfonyl)-1,2,3,6,7,11b-hexahydro-pyrazino(2,1-a)isoquinolin-4-one 4H-pyrazino[2,1-a]isoquinolin-4-one, 3-ethyl-1,2,3,6,7,11b-hexahydro-9,10-dimethoxy-2-[(2-nitrophenyl)sulfonyl]-, (3R,11bS)- InChI=1/C22H25N3O7S/c1-4-16-22(26)23-10-9-14-11-19(31-2)20(32-3)12-15(14)18(23)13-24(16)33(29,30)21-8-6-5-7-17(21)25(27)28/h5-8,11-12,16,18H,4,9-10,13H2,1-3H3/t16-,18-/m1/s rel-(3R,11bS)-3-ethyl-9,10-dimethoxy-2-[(2-nitrophenyl)sulfonyl]-1,2,3,6,7,11b-hexahydro-4H-pyrazino[2,1-a]isoquinolin-4-one