ethyl 4-oxo-2-(2-phenylethenyl)but-2-enoate

4-((1E,3E)-3-Ethoxycarbonyl-5-hydroxy-penta-1,3-dienyl)-benzoic acid methyl ester

ethyl (E,E)-4-hydroxy-2-(4-N-tert-butoxycarbonylaminostyryl)but-2-enoate

(E)-4-Hydroxy-2-[(E)-2-(4-methoxy-phenyl)-vinyl]-but-2-enoic acid ethyl ester

ethyl (E,E)-4-oxo-2-(p-methoxystyryl)but-2-enoate