1 H NMR ( 300 MHz , CDCl 3 ) δ 1 . 64 ( m , 2 H ) , 1 . 78 ( m , 2 H ) , 1 . 96 - 2 . 04 ( m , 4 H ) , 2 . 20 ( s , 3 H ) , 2 . 24 ( t , 2 H ) , 2 . 43 ( m , 1 H ) , 2 . 78 ( brd , 2 H ) , 4 . 50 ( t , 2 H ) , 6 . 96 ( d , 1 H , J = 7 . 8 Hz ) , 7 . 24 - 7 . 33 ( m , 2 H ) , 7 . 42 ( d , 1 H , J = 7 . 8 Hz ) , 7 . 58 ( d , 2 H , J = 8 . 4 Hz ) , 7 . 77 ( d , 2 H , J = 8 . 4 Hz ) , 7 . 86 ( d 1 H , J = 8 . 7 Hz ) , 8 . 24 ( d , d 1 H , J = 8 . 7 Hz , 2 . 1 Hz ) , 8 . 54 ( d , 1 H , J = 2 . 1 Hz ) ; MS ( m / e , M +): 532