PURPOSE: An antiallergic that contains a cyclic compound crosslinked with a specific double bond, as an active ingredient, thus being effective as a preventive and remedy for bronchial asthma and allergic rhinitis.

CONSTITUTION: The objective antiallergic contains a compound of formulaIor II[X is CH, N; Y is (CH2)n (n is 0, 1), CH=CH, N-alkyl, blank; R1, R2 are alkyl, allyl, cycloalkyl, heterocyclic ring; R3 is H, alkyl, aralkyl, cycloalkyl]as an active ingredient. This active ingredient inhibits the liberation of chemotransmitters from mastocytes or basophilic leukocytes to develop antiallergic activity. Some of compounds of formulaIand II are novel.