1 H NMR ( 400 MHz ; DMSO ; Me 4 Si ) , δ ( ppm ) : 13 . 00 ( 1 H , brs ) , 9 . 67 ( 1 H , s ) , 8 . 95 ( 1 H , d , J = 8 Hz ) , 8 . 24 ( 1 H , s ) 7 . 36 - 6 . 97 ( 16 H , m ) , 5 . 76 - 5 . 71 ( 1 H , m ) , 5 . 11 ( 2 H , d , J = 4 Hz ) , 5 . 03 ( 2 H , s ) , 4 . 46 - 4 . 44 ( 1 H , m ) , 3 . 84 ( 1 H , m ) , 3 . 61 ( 3 H , s ) , 3 . 04 - 3 . 00 ( 1 H , m ) , 2 . 96 - 2 . 90 ( 1 H , m ) , 2 . 59 - 2 . 55 ( 3 H , d , J = 16 Hz ) , 1 . 36 ( 3 H , d , J = 4 Hz ) .