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(0)-(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(0)-(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(0)OH wherein m is 1 or 2, 2) CH(CH3)C(0)OH, 3) C(CH3)2C(0)OH, 4) CH(F)-C(0)OH, 5) CF2-C(0)OH, or 6) C(0)-C(0)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.
