(1S,3S)-1,2,3,4-tetrahydro-1-(2-methylpropyl)-2-(trifluoroacetyl)-9H-pyrido<3,4-b>indole-3-carbonitrile

(S)-2-(benzyloxycarbonyl)-1,2,3,4-tetrahydro-1-(2-methylpropyl)-9H-pyrido<3,4-b>indole

(5aS,12S,14aS)-12-isobutyl-11-(3-methylbut-2-en-1-yl)-1,2,3,5a,6,11,12,14a-octahydro-5H,14H-pyrrolo[1'',2'':4',5']pyrazino[1',2':1,6]pyrido[3,4-b]indole-5,14-dione

(1S,3S)-2-((R)-1-Benzyloxycarbonyl-pyrrolidine-2-carbonyl)-1-isobutyl-2,3,4,9-tetrahydro-1H-β-carboline-3-carboxylic acid methyl ester

cis-1-isobutyl-3-methoxycarbonyl-2-Z-L-prolyl-1,2,3,4-tetrahydro-β-carboline