2,3-difluoro-3-[4-[(2,2,2-trifluoroacetyl)amino]phenyl]prop-2-enoic acid

2,3-difluoro-3-(4-iodophenyl)prop-2-enoic acid

2,3-difluoro-3-(2-nitrophenyl)prop-2-enoic acid

methyl 2,3-difluoro-3-(4-nitrophenyl)prop-2-enoate

methyl 3-(4-aminophenyl)-2,3-difluoroprop-2-enoate