1. Instituto de Química, Universidad Nacional Autónoma de México, Av. Universidad 3000, C. U., México City, 04510, Mexico
2. Facultad de Química, Universidad Nacional Autónoma de México, Av. Universidad 3000, C. U., México City, 04510, Mexico
3. Department of Medicinal Chemistry, College of Pharmacy, University of Utah, 2000 East 30 South Skaggs 201, Salt Lake City, UT 84112, USA