Abstract: A pyridine compound of the formula ##STR1## wherein X is a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxyl group having 1 to 4 carbon atoms, a haloalkyl group having 1 to 4 carbon atoms or a haloalkoxyl group having 1 to 4 carbon atoms, n is 1 to 5, and when n is 2 or more, Xs may be identical to or different from each other, A is an alkyl residue or alkene residue in which a portion connecting the aryl group with the 4-position of the pyridyl group has 3 to 8 carbon atoms, or an alkapolyene residue in which said portion has 4 to 8 carbon atoms and 2 to 4 double bonds; the alkyl residue, alkene residue, and alkapolyene residue may have an alkyl side chain having 1 to 4 carbon atoms, an alkylidene side chain having 1 to 4 carbon atoms or 1 to 16 halogen atoms, and when there are 2 or more side chains, the side chains may be identical to or different from each other, and R.sup.1 and R.sup.