| abstract |
Disclosed is a compound of formula (I) or a pharmaceutically acceptable salt thereof in the manufacture of a medicament for the therapeutic and / or prophylactic treatment of Duchenne muscular dystrophy, Becker muscular dystrophy or cachexia.n n n <Formula I>n n n n n n n n In the formula,n n n A 1 , A 2 , A 3 and A 4 , which may be the same or different, represent N or CR 1 ,n n n X is a divalent group selected from O, S (O) n , C = W, NR 4 , NC (= 0) R 5 and CR 6 R 7 ,n n n W is O, S, NR 20 ,n n n Y is N or CR 8 ,n n n One of R 4 , R 5 , R 6 , R 8 , R 9 and NR 20 represents -LR 3 , where L is a single bond or a linking group,n n n Also,n n n R 1 , R 3 to R 9 , which may be the same or different, independently represent hydrogen or a substituent,n n n R 2 O is hydrogen, hydroxyl, alkyl optionally substituted with aryl, alkoxy optionally substituted with aryl, aryl, CN, optionally substituted alkoxy, optionally substituted aryloxy, optionally substituted alkanoyl, optionally substituted aroyl, NO 2 , NR 30 R 31 , wherein R 30 and R 31, which may be the same or different, represent hydrogen, optionally substituted alkyl or optionally substituted aryl; In addition, one of R 30 and R 31 may represent an optionally substituted alkanoyl or an optionally substituted aroyl,n n n n represents an integer of 0 to 2,n n n Also,n n n When an adjacent pair of A 1 to A 4 each represents CR 1 , adjacent carbon atoms can form ring B with their substituents,n n n When X is CR 6 R 7 , R 6 and R 7 together with the carbon atom to which they are attached may form ring C. |