1 H NMR ( 300 MHz , CDCl 3 ) δ 1 . 48 ( m , 2 H ) , 1 . 71 - 2 . 00 ( m , 8 H ) , 2 . 15 ( s , 3 H ) , 2 . 30 ( t , 2 H ) , 2 . 42 ( m , 1 H ) , 2 . 91 ( br , 2 H ) , 4 . 26 ( t , 2 H ) , 6 . 95 ( d , 1 H ) , 7 . 23 - 7 . 38 ( m , 6 H ) , 7 . 45 - 7 . 52 ( m , 3 H ) , 7 . 67 ( d , 2 H ) , 7 . 80 ( m , 1 H ) ; MS ( m / e , M +): 500 , 458 , 324 , 284 ,