1 H - NMR : ( 300 MHz , DMSO - d 6 ) δ 11 . 41 ( s , 1 H ) , 9 . 87 ( s , 1 H ) , 8 . 22 ( s , 1 H ) , 7 . 41 ( d , 1 H , J = 7 . 65 Hz ) , 7 . 28 ( m , 2 H , J = 7 . 35 Hz , 7 . 7 Hz ) , 6 . 06 ( s , 1 H ) , 4 . 80 ( t , 1 H , J = 5 . 5 Hz ) , 4 . 23 ( broad d , 2 H , 11 . 85 Hz ) , 4 . 048 ( t , 3 H , J = 5 . 25 ) , 3 . 57 ( q , 2 H , J = 5 . 3 Hz ) , 2 . 88 ( t , 2 H , 12 . 55 Hz ) , 2 . 40 ( s , 3 H ) , 2 . 28 ( d , 2 Hz , J = 7 Hz ) , 2 . 24 ( s , 3 H ) , 1 . 99 ( b , 1 H ) , 1 . 76 ( d , 2 H , J = 12 . 75 ) , 1 . 16 ( m , 2 H ) .