1 H NMR ( CD 3 OD ) δ : 9 . 71 ( s , 1 H ) , 7 . 59 - 7 . 61 ( m , 2 H ) , 7 . 33 - 7 . 42 ( m , 3 H ) , 6 . 93 ( s , 1 H ) , 6 . 65 ( s , 1 H ) , 4 . 52 - 4 . 81 ( m , 4 H ) , 3 . 87 ( s , 3 H ) , 3 . 70 ( brs , 1 H ) , 2 . 25 ( m , 1 H ) , 1 . 08 - 1 . 77 ( m , 10 H ) .