6-benzyl-5,6,7,8-tetrahydro-1,6-naphthyridin-2-ol

6-benzyl-1,2,5,6,7,8-hexahydro-1,6-naphthyridin-2-one

6-benzyl-5,6,7,8-tetrahydro-1,6-naphthyridin-2(1H)-one