1 H NMR ( 500 MHz , DMSO - d 6 ) 9 . 78 ( NH , br s , 1 H ) , 7 . 46 ( d , J = 8 . 5 Hz , 2 H ) , 7 . 27 - 7 . 24 ( m , 2 H ) , 7 . 21 - 7 . 15 ( m , 4 H ) , 7 . 09 - 7 . 05 ( m , 4 H ) , 7 . 02 - 6 . 99 ( m , 1 H ) , 5 . 05 ( OH , t , J = 5 . 5 Hz , 1 H ) , 4 . 39 ( d , J = 5 . 5 Hz , 2 H ) , 4 . 13 - 4 . 08 ( m , 1 H ) , 3 . 95 - 3 . 89 ( m , 1 H ) , 3 . 80 - 3 . 74 ( m , 2 H ) , 3 . 21 ( sep , J = 7 . 0 Hz , 1 H ) , 2 . 30 ( dd , J = 15 . 0 Hz , 5 . 0 Hz , 1 H ) , 2 . 19 - 2 . 15 ( m , 1 H ) , 1 . 63 - 1 . 50 ( m , 2 H ) , 1 . 38 ( s , 9 H ) , 1 . 36 ( d , J = 7 . 0 Hz , 6 H ) , 1 . 35 - 1 . 30 ( m , 1 H ) , 1 . 31 ( s , 3 H ) , 1 . 16 ( s , 3 H ) , 0 . 96 - 0 . 89 ( m , 1 H ) .