1 H NMR ( 300 MHz , CDCl 3 ) δ 1 . 74 - 2 . 29 ( 4 H , m ) , 3 . 26 - 3 . 37 ( 2 H , m ) , 3 . 40 - 3 . 60 ( 2 H , m ) , 3 . 87 - 4 . 10 ( 3 H , m ) , 7 . 30 ( 1 H , d , J = 1 . 9 Hz ) , 7 . 42 - 7 . 51 ( 2 H , m ) , 7 . 56 - 7 . 63 ( 1 H , m ) , 7 . 75 - 7 . 85 ( 3 H , m ) .