1 H 　 NMR ( DMSO - d 6 , 400 MHz ) δ 10 . 43 ( s , 1 H ) , 9 . 66 ( s , 1 H ) , 9 . 18 ( s , 1 H ) , 7 . 81 ( br , 2 H ) , 7 . 66 ( s , 1 H ) , 7 . 09 ( s , 1 H ) , 7 . 08 - 1 . 06 ( m , 2 H ) , 4 . 00 ( s , 6 H ) , 3 . 75 - 3 . 58 ( m , 2 H ) , 3 . 25 - 2 . 72 ( m , 3 H ) , 2 . 44 - 2 . 08 ( m , 4 H ) , 1 . 87 - 1 . 34 ( m , 4 H ) .