1. Department of Pharmacology and Toxicology, Division of Medicinal and Natural Products Chemistry, College of Pharmacy, University of Arizona, Tucson, Arizona 85721, Institute for Tuberculosis Research (M/C 964), College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois 60612, and Departamento de Ciencias Vegetales, Facultad de Agronomía e Ingeniería Forestal, Pontificia Universidad Católica de Chile, Avenida Vicuña Mackenna 4860, Santiago, Chile