2-fluoro-4-hydroxybenzoic acid 4-bromo-3-fluoroanisole 4-ethoxyphenylacetylene 4-cyano-4-ethylbiphenyl 1-bromo-4-iodobenzene 4-ethoxycinnamic acid triphenyl amine derivatives 4-(4-n-pentylphenyl)benzoic acid 2-fluoro-4-hydroxybenzonitrile