1. Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry and Pharmacy, Northwest A&F University, Yangling, Shaanxi 712100, People’s Republic of China
2. School of Pharmaceutical Sciences, South Central University for Nationalities, Wuhan, Hubei 430074, People’s Republic of China
3. Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, United States
4. Departamento de Química Fundamental, Universidade Federal de Pernambuco, Avenida Professor Moraes Rego, 1235, Cidade Universitária, Recife, Pernambuco 50670-901, Brazil