| abstract |
Novel isoxazole and thiazole compounds of the general formula [1] and salts thereof; and use of both as excellent lysophosphatidic acid (LPA) receptor antagonists, wherein R1 and R2 are each optionally substituted alkyl or the like; R3 is hydrogen or the like; R4 is a group selected from the group consisting of (I) phenyl, aryl, and heterocyclic groups which may be substituted, (II) optionally substituted alkyl, and (III) optionally substituted alkenyl; and X is oxygen or sulfur, with the provisos that R3 and R4 together with the carbon atom to which they are bonded may form a cyclic structure and that when R3 is hydrogen, R4 is a group exclusive of methyl. |