viruses Article Identification of a Novel Inhibitor against Middle East Respiratory Syndrome Coronavirus Yaping Sun 1,2, Huaidong Zhang 1, Jian Shi 1, Zhe Zhang 1 and Rui Gong 1,* 1 Center for Emerging Infectious Diseases, CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, No. 44 Xiao Hong Shan, Wuhan 430071, China;