A compound of Formula (I): or a metabolite thereof, or an ester of the compound of Formula (I) or the metabolite thereof, or a pharmaceutically acceptable salt of each thereof, wherein m, n, X1 and X2 are as defined herein, is useful for inhibiting or treating idiopathic pulmonary fibrosis, conditions leading to or arising from it, and/or negative effects of each thereof.具化學式(I)之一化合物:或其代謝物,或具化學式(I)的化合物之酯類或其代謝物,或其中各者之藥學上可接受的鹽類,其中m、n、X1及X2係如本申請案中所界定,其係適用於抑制或治療自發性肺纖維化、導致自發性肺纖維化或由其產生之病況及/或其中各者的負面影響。