1. Department of Chemistry; The RNA Institute; University at Albany; State University of New York; 1400 Washington Ave. Albany NY 12222 USA
2. Institute of Biosciences and Technology; Texas A&M Health Science Center; 2121 W. Holcombe Blvd Houston TX 77030 USA
3. Department of Chemistry; University of South Florida; 4202 E. Fowler Ave. Tampa FL 33620 USA
4. School of Pharmacy; Shandong University; 44 Wenhua Road W. Jinan Shandong 250012 China