Carbostyril derivatives and antiallergic agent.

摘要

1. A compound of the formula: <CHEM> wherein the symbol of a solid line with a broken line means a single bond or a double bond, R and R' are independently selected from the group consisting of hydrogen atom, halogen atom, lower alkyl, nitro, unsubstituted amino and substituted amino, A and B are independently selected from the group consisting of hydrogen atom, lower alkyl optionally substituted with a lower cycloalkyl, aryl optionally substituted with one or more halogen atoms and the group: -Y-R<2> wherein Y is lower alkylene and R<2> is the group: <CHEM> wherein m is integer of 1 to 3, n is 0 or 1, Z is >N-, >CH- or >C=, R<3> is diaryl(lower)alkyl optionally substituted with one or more halogen atoms or is condensed heterocyclic group optionally substituted with oxo, with the proviso that (a) at least one of A and B is the group -Y-R<2>, and (b) when A is hydrogen atom and B is the group -Y-R<2>, then Z is >CH- or >C= if R<3> is condensed heterocyclic group optionally substituted with oxo and n is O or a pharmaceutically acceptable salt thereof. The compounds of the above formula have antiallergic activity.