(R)-ethyl 7-(8-acetoxy-2,3-diphenyl-7,8-dihydropyrido[2,3-b]pyrazin-5(6H)-yl)heptanoate

rac-ethyl 7-(8-ethyl-2,3-diphenyl-7,8-dihydropyrido[2,3-b]pyrazin-5(6H)-yl)heptanoate

(R)-7-(8-hydroxy-2,3-diphenyl-7,8-dihydropyrido[2,3-b]pyrazin-5(6H)-yl)heptanoic acid

(E)-7-(2,3-diphenyl-7,8-dihydropyrido[3,2-b]pyrazin-5(6H)-yl)hept-3-enoic acid

rac-5-(tert-butoxycarbonyl)-2,3-diphenyl-5,6,7,8-tetrahydropyrido[2,3-b]pyrazine-7,8-diyl diacetate