Department of Pharmacology, Northwestern University, Chicago, Illinois 60611, Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin, Madison, Wisconsin 53706, Laboratory of Chemistry for Natural Products, Tokyo Institute for Natural Products, Tokyo Institute for Technology, and Tokyo College of Pharmacology, Tokyo, Japan

Department of Pharmacology, Northwestern University, Chicago, Illinois 60611, Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin, Madison, Wisconsin 53706, Laboratory of Chemistry for Natural Products, Tokyo Institute for Natural Products, Tokyo Institute for Technology, and Tokyo College of Pharmacology, Tokyo, Japan

Department of Pharmacology, Northwestern University, Chicago, Illinois 60611, Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin, Madison, Wisconsin 53706, Laboratory of Chemistry for Natural Products, Tokyo Institute for Natural Products, Tokyo Institute for Technology, and Tokyo College of Pharmacology, Tokyo, Japan

Department of Pharmacology, Northwestern University, Chicago, Illinois 60611, Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin, Madison, Wisconsin 53706, Laboratory of Chemistry for Natural Products, Tokyo Institute for Natural Products, Tokyo Institute for Technology, and Tokyo College of Pharmacology, Tokyo, Japan

Department of Pharmacology, Northwestern University, Chicago, Illinois 60611, Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin, Madison, Wisconsin 53706, Laboratory of Chemistry for Natural Products, Tokyo Institute for Natural Products, Tokyo Institute for Technology, and Tokyo College of Pharmacology, Tokyo, Japan