ENANTA PHARMACEUTICALS, INC.; TANG, Datong; XU, Guoyou; PENG, Xiaowen; YING, Lu; WANG, Ce; CAO, Hui; LONG, Jiang; KIM, In, Jong; WANG, Guoqiang; QIU, Yao-ling; OR, Yat, Sun Patent: WO2013/59281 A2, 2013