4-[2-(4-ethoxycarbonylphenyl)ethenyl]benzenesulfonic acid
4-[(E)-2-(4-ethoxycarbonylphenyl)ethenyl]benzenesulfonic acid
4-[(E)-2-(4-ethoxycarbonylphenyl)vinyl]benzenesulfonic acid
4-[2-(4-ethoxycarbonylphenyl)vinyl]benzenesulfonic acid
4-[(E)-2-(4-carbethoxyphenyl)vinyl]benzenesulfonic acid
4-[2-(4-carbethoxyphenyl)vinyl]benzenesulfonic acid