6-chloro-1-(2-methoxycarbonylethyl)-1,3,4,9-tetrahydro-β-carboline-2-carboxylic acid tert-butyl ester

6-chloro-2-(4-nitrobenzenesulfonyl)-1-vinyl-2,3,4,9-tetrahydro-1H-β-carboline

10-chloro-6-oxo-1,2,3a,4,5,6-hexahydroindolo[3,2,1-de][1,5]naphthyridine-3-carboxylic acid tert-butyl ester

6-chloro-1-(2-methoxycarbonylvinyl)-1,3,4,9-tetrahydro-β-carboline-2-carboxylic acid tert-butyl ester

6-chloro-1-vinyl-2,3,4,9-tetrahydro-1H-β-carboline