1 H NMR ( 400 MHz , CD 3 OD ) δ = 8 . 70 ( s , 1 H ) , 8 . 49 ( s , 1 H ) , 8 . 23 ( s , 1 H ) , 8 . 09 ( s , 1 H ) , 6 . 34 ( br s , 2 H ) , 5 . 83 ( br s , 2 H ) , 5 . 73 - 5 . 53 ( m , 2 H ) , 5 . 38 - 5 . 01 ( m , 2 H ) , 4 . 76 - 4 . 32 ( m , 6 H ) , 3 . 95 ( br s , 2 H ) , 3 . 69 - 3 . 64 ( m , 2 H ) ; 31 P NMR ( 162 MHz , CD 3 OD ) δ = 55 . 57 ( s , 1 P ) , 55 . 32 ( s , 1 P ) .