1. Department
of Chemistry and Biochemistry and ‡Skaggs School of Pharmacy and Pharmaceutical
Sciences, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0358,
United States
2. Pharmacognosy
Laboratory and ⊥Department of Biochemistry, Federal University of South Brazil, Porto Alegre, 90610-000, RS, Brazil