1 H NMR ( 400 MHz , DMSO ) δ 8 . 33 ( d , J = 2 . 9 Hz , 1 H ) , 8 . 06 ( d , J = 3 . 1 Hz , 1 H ) , 7 . 88 ( dd , J = 14 . 9 , 2 . 9 Hz , 1 H ) , 7 . 64 ( d , J = 2 . 9 Hz , 1 H ) , 7 . 62 - 7 . 57 ( m , 1 H ) , 7 . 57 - 7 . 53 ( m , 1 H ) , 7 . 36 ( d , J = 2 . 9 Hz , 1 H ) , 7 . 31 ( d , J = 15 . 0 Hz , 1 H ) , 6 . 89 ( s , 2 H ) , 4 . 07 ( t , J = 14 . 4 Hz , 2 H ) , 3 . 54 ( s , 2 H ) , 2 . 72 ( t , J = 14 . 4 Hz , 2 H ) , 2 . 52 - 2 . 44 ( m , 4 H ) , 2 . 38 - 2 . 30 ( m , 4 H ) , 2 . 27 ( s , 6 H ) , 2 . 14 ( s , 3 H ) . LR - MS ( ESI ) m / z 615 ( M + 1 ) .