1 H NMR ( DMSO d 6 ) δ 8 . 42 ( 1 H , d , J = 4 . 6 Hz ) , 8 . 34 ( 1 H , br ) , 7 . 48 ( 1 H , br s ) , 7 . 39 ( 1 H , d , J = 7 . 9 Hz ) , 7 . 34 ( 1 H , br s ) , 7 . 22 ( 1 H , dd , J = 7 . 9 , 4 . 6 Hz ) , 5 . 11 ( 1 H , d , J = 3 . 3 Hz ) , 4 . 55 ( 1 H , br ) , 4 . 37 ( 2 H , d , J = 4 . 6 Hz ) , 3 . 73 ( 1 H , dd , J = 5 . 9 , 5 . 9 Hz ) , 2 . 36 ( 3 H , s ) , 2 . 22 ( 1 H , m ) , 2 . 05 ( 1 H , m ) , 1 . 84 ( 1 H , m ) , 1 . 65 ( 1 H , m ) .