7-(2-{1-[2-ethoxycarbonyl-1-(2-methoxy-phenyl)-ethyl]-1H-indol-5-yloxy}-ethyl)-3,4-dihydro-2H-[1,8]naphthyridine-1-carboxylic acid tert-butyl ester

7-{2-[1-(2-Ethoxycarbonyl-1-naphthalen-2-yl-ethyl)-1H-indol-5-yloxy]-ethyl}-3,4-dihydro-2H-[1,8]naphthyridine-1-carboxylic acid tert-butyl ester

7-(2-{1-[2-Ethoxycarbonyl-1-(5-methanesulfonyl-pyridin-3-yl)-ethyl]-1H-indol-5-yloxy}-ethyl)-3,4-dihydro-2H-[1,8]naphthyridine-1-carboxylic acid tert-butyl ester

3-phenyl-3-{5-[2-(5,6,7,8-tetrahydro-[1,8]naphthyridin-2-yl)-ethoxy]-indol-1-yl}-propionic acid

3-{5-[2-(5,6,7,8-tetrahydro-[1,8]naphthyridin-2-yl)-ethoxy]-indol-1-yl}-hexanoic acid ethyl ester