1. Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, United States
2. Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093-0358, United States
3. Department of Chemistry, University of Riau, Faculty of Mathematics and Natural Sciences, Pekanbaru 28293, Indonesia