methyl 3-hydroxy-5-methyl-2-methylene-4-hexenoate

(2'R,3'R,4'S,5'S)-2'-(2-Methoxy-2-methyl-propyl)-2-oxo-1,2-dihydro-spiro[indole-3,3'-pyrrolidine]-4',5'-dicarboxylic acid 4'-ethyl ester

(1S,2R,3R,5aS,10aS)-1',2',5a,6,7,8,10,10a-octahydro-3-(2-methoxy-2-methylpropyl)-2',5,10-trioxospiro[1H,5H-dipyrrolo[1,2-a:1',2'-d]pyrazine-2(3H),3'-[3H]indole]-1-carboxylic acid ethyl ester

(1S,2R,3R,5aR,10aS)-1',2',5a,6,7,8,10,10a-octahydro-3-(2-methoxy-2-methylpropyl)-2',5,10-trioxospiro[1H,5H-dipyrrolo[1,2-a:1',2'-d]pyrazine-2(3H),3'-[3H]indole]-1-carboxylic acid ethyl ester

(2'R,3R,4'S,5'S)-1,2-dihydro-2'-(2-methoxy-2-methylpropyl)-2-oxo-5'-[[(2R)-2-[(phenylmethoxy)carbonyl]-1-pyrrolidinyl]carbonyl]spiro[3H-indole-3,3'-pyrrolidine]-4'-carboxylic acid ethyl ester