A series of isoxazole derivatives were synthesized and their antagonistic activities against LPA stimulation on both LPA1/CHO cells and rHSC cells were evaluated. Among them, 3-(4- {4-[1-(2-chloro-cyclopent-1-enyl)-ethoxycarbonylamino]-isoxazol-3-yl}-benzylsulfanyl)- propionic acid (34) showed the most potent activities.