The present invention relates to compounds of: or a pharmaceutically acceptable salt thereof, wherein A is C5 alkyl, C6 alkyl, C5 alkenyl, C6 alkenyl, C(O)-(CH2)n-CH3 or CH(OH)-(CH2)n-CH3 wherein n is 3 or 4; R1 is H, F or OH; R2 is C5 alkyl, C6 alkyl, C5 alkenyl, C6 alkenyl, C(O)-(CH2)n-CH3 or CH(OH)-(CH2)n-CH3 wherein n is 3 or 4; R3 is H, F, OH or CH2Ph; R4 is H, F or OH; Q is 1) (CH2)mC(O)OH wherein m is 1 or 2, 2) CH(CH3)C(O)OH, 3) C(CH3)2C(O)OH, 4) CH(F)-C(O)OH, 5) CF2-C(O)OH, or 6) C(O)-C(O)OH; and compositions comprising the same and the method using the same for the prevention or treatment of various fibrotic diseases and conditions in subjects, including pulmonary fibrosis, liver fibrosis, skin fibrosis, renal fibrosis, pancreas fibrosis, systemic sclerosis, cardiac fibrosis or macular degeneration.本發明係關於如下化合物:或其醫藥學上可接受之鹽,其中A為C5烷基、C6烷基、C5烯基、C6烯基、C(O)-(CH2)n-CH3或CH(OH)-(CH2)n-CH3,其中n為3或4;R1為H、F或OH;R2為C5烷基、C6烷基、C5烯基、C6烯基、C(O)-(CH2)n-CH3或CH(OH)-(CH2)n-CH3,其中n為3或4;R3為H、F、OH或CH2Ph;R4為H、F或OH;Q為1)(CH2)mC(O)OH,其中m為1或2,2)CH(CH3)C(O)OH,3)C(CH3)2C(O)OH,4)CH(F)-C(O)OH,5)CF2-C(O)OH,或6)C(O)-C(O)OH;和包含其之組成物以及使用其用於預防或治療個體之各種纖維變性疾病及病狀,包括肺纖維化、肝纖維化、皮膚纖維化、腎纖維化、胰纖維化、全身性硬化、心臟纖維化或黃斑變性的方法。