1 H NMR ( 300 MHz , CDCl 3 ) δ 1 . 59 ( m , 2 H ) , 1 . 74 ( m , 2 H ) , 1 . 91 - 2 . 03 ( m , 4 H ) , 2 . 18 ( t , 2 H , J = 6 . 0 Hz ) , 2 . 27 ( s , 3 H ) , 2 . 44 ( m , 1 H ) , 2 . 87 ( m , 2 H ) , 3 . 30 ( m , 2 H ) , 3 . 40 ( m , 2 H ) , 4 . 29 ( t , 2 H , J = 6 . 4 Hz ) , 6 . 87 ( m , 1 H ) , 7 . 05 ( s , 1 H ) , 7 . 21 - 7 . 32 ( m 4 H ) , 7 . 38 ( m , 1 H ) , 7 . 71 ( dt , 1 H , J = 7 . 8 , 1 . 8 Hz ) , 7 . 77 ( m , 1 H ) , 7 . 89 ( br dd , 1 H , J = 8 . 2 , 1 . 2 Hz ) , 8 . 51 ( dd , 1 H , J = 4 . 8 , 1 . 6 Hz ) , 8 . 76 ( d , 1 H , J = 1 . 8 Hz ) , 9 . 37 ( br s , 1 H ) ; MS ( m / e , M +): 481 ( M +), 245 , 159 , 70 .