1 H NMR ( 600 MHz , DMSO - d 6 ) d = 8 . 97 ( d , J = 6 Hz , 1 H ) , 7 . 72 - 7 . 66 ( m , 2 H ) , 7 . 55 - 7 . 40 ( m , 3 H ) , 7 . 22 - 7 . 16 ( m , 3 H ) , 6 . 36 ( s , 1 H ) , 4 . 86 - 4 . 80 ( m , 1 H ) , 4 . 17 ( t , J = 9 . 0 Hz , 1 H ) , 3 . 96 - 3 . 89 ( m , 4 H ) , 3 . 85 - 3 . 82 ( m , 1 H ) , 3 . 63 - 3 . 57 ( m , 2 H )