Provided are IDO inhibitor compounds of Formula I and pharmaceutically acceptable salts thereof, their pharmaceutical compositions, their methods of preparation, and methods for their use in the prevention and/or treatment of diseases such as chronic viral infection, chronic bacterial infections, cancer, sepsis or a neurological disorder.
                            本发明提供了式 I 的 
IDO 抑制剂化合物及其药学上可接受的盐、其药物组合物、其制备方法以及用于预防和/或治疗慢性病毒感染、慢性细菌感染、癌症、败血症或神经紊乱等疾病的方法。