NH2 NHCOCH NHCOCH (CH3 CO)2O B uridine NH Br t ch3co2h HCI Br ①D NH2 ⑨D NaHcoOrganic Chemistry Organic Chemistry Xiamen Xiamen University University NH 2 (CH 3CO) 2 O Py r idi n e NHCOCH 3 NHCOCH 3 Br 2 Br H 2 O HCl NH 2 Br + C H 3CO 2 H NH 2 I 2 NaHCO 3 NH 2 I