1 H NMR ( 400 MHz , DMSO - d 6 ) : δ 9 . 71 ( s , 1 H ) , 8 . 48 ( d , J = 8 . 4 Hz , 1 H ) , 8 . 08 ( s , 1 H ) , 7 . 79 - 7 . 83 ( m , 1 H ) , 7 . 59 ( d , J = 6 . 8 Hz , 1 H ) , 7 . 10 ( s , 1 H ) , 5 . 86 ( dd , J = 10 . 8 , 3 . 6 Hz , 1 H ) , 5 . 86 ( dd , J = 3 . 6 , 7 . 2 Hz , 1 H ) , 4 . 40 ( dd , J = 14 . 8 , 3 . 6 Hz , 1 H ) , 4 . 16 - 4 . 19 ( m , 1 H ) , 4 . 10 ( q , J = 7 . 2 Hz , 2 H ) , 3 . 82 ( s , 3 H ) , 3 . 09 ( s , 3 H ) , 2 . 19 ( s , 3 H ) , 1 . 32 ( t , J = 7 . 2 Hz , 3 H ) . LCMS : [ ( M + 1 ) ] + = 461 . 9 .