1 H NMR ( 400 MHz , DMSO - d 6 ) : δ ppm 12 . 14 ( s , 1 H ) , 10 . 07 ( s , 1 H ) , 8 . 30 - 8 . 27 ( m , 1 H ) , 8 . 19 ( s , 1 H ) , 8 . 12 ( d , J = 8 . 4 Hz , 1 H ) , 8 . 05 - 8 . 00 ( m , 2 H ) , 7 . 94 - 7 . 92 ( m , 1 H ) , 7 . 74 - 7 . 73 ( m , 1 H ) , 7 . 66 - 7 . 59 ( m , 3 H ) , 6 . 76 ( s , 1 H ) , 4 . 24 ( s , 3 H ) . ( ESI ) : m / z 369 . 1 [ M + H ] +.