1 H NMR ( 300 MHz , DMSO - d 6 ) δ 10 . 84 ( s , 1 H ) , 8 . 75 ( d , J = 8 . 4 Hz , 1 H ) , 7 . 86 - 7 . 82 ( m , 1 H ) , 7 . 59 ( d , J = 6 . 4 Hz , 1 H ) , 7 . 28 ( d , J = 8 . 4 Hz , 1 H ) , 7 . 04 ( d , J = 8 . 4 Hz , 1 H ) , 5 . 81 - 5 . 70 ( m , 1 H ) , 4 . 31 - 4 . 16 ( m , 4 H ) , 3 . 76 ( s , 3 H ) , 3 . 16 ( s , 2 H ) , 3 . 10 ( s , 3 H ) , 2 . 32 ( s , 6 H ) , 1 . 16 ( t , J = 7 . 2 Hz , 3 H ) . LCMS : [ M + H ] + = 505 . 2 .