5'-tert-Butoxycarbonyl-3,3'-diethyl-4,4'-dimethyl-2,2'-dipyrrylmethane-5-carboxylic acid

benzyl 4-(2-ethoxycarbonylethyl)-3-ethoxycarbonylmethyl-3'-ethyl-5'-formyl-4'-methyl-2,2'-dipyrrylmethane-5-carboxylate

t-butyl 3'-2-ethyl-5-formyl-4-(2-methoxycarbonylethyl)-3,4'-dimethylpyrromethane-5'-carboxylate

3-ethyl-18-(2-chloroethyl)-8,12-bis-(2-methoxycarbonylethyl)-2,7,13,17-tetramethyl-b-bilene-1,19-dicarboxylic acid hydrobromide