[6-(4-Carbamimidoyl-phenylethynyl)-1-oxo-3,4-dihydro-1H-isoquinolin-2-yl]-acetic acid tert-butyl ester

2-tert-Butoxycarbonylmethyl-1-oxo-1,2,3,4-tetrahydro-isoquinoline-6-carboxylic acid methyl ester

{6-[4-(tert-Butoxycarbonylamino-imino-methyl)-phenylethynyl]-1-oxo-3,4-dihydro-1H-isoquinolin-2-yl}-acetic acid tert-butyl ester

6-amino-3,4-dihydro-1-oxo-2(1H)-isoquinolineacetic acid 1,1-dimethylethyl ester

6-[(3-{[N,N'-bis[(1,1-dimethylethoxy)carbonyl]aminoiminomethyl]amino}butyl)oxy]-3,4-dihydro-1-oxo-2(1H)-isoquinolineacetic acid 1,1-dimethylethyl ester