The present invention provides a pharmaceutical composition for use as a Th2 differentiation inhibitor comprising a compound represented by Formula (I): ##STR1##

wherein each of ring A, ring B and ring C is an aromatic carbocyclic ring, a heterocyclic ring and the like, X is a single bond, —O—, —CH₂—, —NH—, —SO— and the like, Y is hydrogen, optionally substituted lower alkyl, optionally substituted lower alkenyl and the like, each of V¹ and V² is a single bond, —O—, —NH—, —OCH₂— and the like, a prodrug, pharmaceutically acceptable salt or solvate thereof.