Leslie Gunatilaka

Leslie Gunatilaka

Professor, Natural Resources and the Environment
Director, Natural Products Center
Professor, Pharmacology and Toxicology
Professor, Cancer Biology - GIDP
Professor, Arid Lands Resources Sciences - GIDP
Professor, BIO5 Institute
Contact
(520) 621-9932

Work Summary

Discovery of natural products from plants and their associated microorganisms as potential drugs to treat cancer. Application of medicinal chemistry approach for structure-activity relationship studies and to obtain compounds for preclinical evaluation. Development of alternative agricultural systems for sustainable utilization of natural resources.

Research Interest

Despite many therapeutic successes, cancer remains a major cause of mortality in the US. Natural products (NPs) represent the best source and inspiration for the discovery of drugs and molecular targets. Our aim is to discover effective and non-toxic NP-based anticancer drugs. Working with NCI we have recently discovered a class of plant-derived NPs useful in cancer immunotherapy. The main focus of our current research is to utilize medicinal chemistry approach to obtain their analogues for preclinical evaluation. Leslie Gunatilaka is Professor at the School of Natural Resources and the Environment and Director of the Natural Products Center. He is also Adjunct Professor of Department of Nutritional Sciences, and a member of the Arizona Cancer Center. He is a member of several professional societies, editorial boards, and pharmaceutical company advisory groups. He is a Fellow of the Academy of Sciences for the Developing World (TWAS), Italy, and the National Academy of Sciences, Sri Lanka. Dr. Gunatilaka has over 200 peer-reviewed publications and book chapters and over 150 communications in natural product science to his credit. He is the recipient of the Sri Lankan Presidents’ gold medal for “creating a center of excellence in natural products research at the University of Peradeniya, Sri Lanka” (1987), CaPCURE award for “dedication to ending prostate cancer as a risk for all men and their families” (2000), Research Faculty of the Year Award of the UA College of Agriculture and Life Sciences (2003), the UA Asian American Faculty, Staff and Alumni Association Outstanding Faculty Award (2005), and the UA Leading Edge Researcher Award for Innovative Research (2012). He has delivered over 100 invited lectures worldwide and was the Chief Guest and Plenary Lecturer at the International Herbal Medicine Conference held in Sri Lanka (2005), and the Keynote Speaker and the Guest of Honor at Chemtech-2007, an International Conference organized by the Institute of Chemistry, Ceylon. His current research interests include discovery, identification of protein targets, and structure-activity relationship (SAR) studies of natural product-based drugs to treat cancer, neurodegenerative, and other diseases from plants, and plant- and lichen-associated microorganisms, maximization of chemistry diversity and production of microbial and plant secondary metabolites, and scientific investigation of medicinal plants and herbal supplements. Keywords: Natural Product-Based Drug Discovery, Medicinal Chemistry, Cancer Immunotherapeutic Agents

Publications

Xu, Y., Bashyal, B. P., Liu, M. X., Espinosa-Artiles, P., U'Ren, J. M., Arnold, A. E., & Gunatilaka, A. L. (2015). Cytotoxic Cytochalasins and other Metabolites from Xylariales sp. FL0390, A Fungal Endophyte of the Spanish moss. Natural Product Communications, 10(10), 1655-1658.
Wijeratne, E. K., Liu, M. X., Kantipudi, N. B., Brochini, C. B., Gunatilaka, A. L., & Canfield, L. M. (2006). Synthesis and preliminary biological evaluation of β-carotene and retinoic acid oxidation products. Bioorganic and Medicinal Chemistry, 14(23), 7875-7879.

PMID: 16908162;Abstract:

Synthesis of the β-carotene oxidation product, 2,3-dihydro-5,8-endoperoxy-β-apo-carotene-13-one (1) was achieved in six steps starting from β-ionone. Photo-oxygenation of all trans-retinoic acid (8) and 13-cis-retinoic acid (9) produced a mixture of 5S*,8S*-epidioxy-5,8-dihydroretinoic acid (10) and 13-cis-5S*,8S*-epidioxy-5,8-dihydroretinoic acid (11). Methylation of the crude photo-oxygenation mixture afforded the corresponding methyl esters 12 and 13, respectively, both of which underwent ready aerial oxidation yielding hitherto unknown oxidation products of retinoic acid identified as methyl 5S*,8S*-epidioxy-9,10β-epoxy-5,8,9,10-tetrahydroretinoate (14) and methyl 13-cis-5S*,8S*-epidioxy-9,10β-epoxy-5,8,9,10-tetrahydroretinoate (15). Evaluation of 1, all trans-retinoic acid (8), 13-cis-retinoic acid (9), and the photo-oxygenation products 10-15 in a panel of five cancer cell lines showed 1 to be inactive and that 11 is significantly cytotoxic compared with the other retinoic acid analogs suggesting the requirement of the carboxylic acid moiety and the cis-geometry of the 13(14) double bond for cytotoxic activity. © 2006 Elsevier Ltd. All rights reserved.

Gunatilaka, A., & Kingston, D. G. (1997). DNA-damaging natural products with potential anticancer activity. Studies in Natural Products Chemistry, 20(PART F), 457-505.
Kamal, G. M., Gunaherath, B., Gunatilaka, A., & Thomson, R. H. (1984). Structure of plumbazeylanone: a novel trimer of plumbagin from plumbago zeylanica. Tetrahedron Letters, 25(42), 4801-4804.

Abstract:

Plumbazeylanone, a quinone from Plumbago zeylanica is probably 5b,11a,12,12a-tetrahydro-1,7-dihydroxy-5b-(8-hydroxy-3-methyl-1,4-naphthoquinon-2-yl)-5a,12a-dimethyl-5aH-dibenzo[b,h]fluorene-5,13:6,11-diquinone, a novel trimer of plumbagin with an additional methyl group. © 1984.

A., A., G., D., M., E., M., B., Hofmann, G. A., & Johnson, R. K. (1994). Biological activity of some coumarins from Sri Lankan Rutaceae. Journal of Natural Products, 57(4), 518-520.

PMID: 8021652;Abstract:

Twelve coumarins isolated from plants of the Rutaceae collected in Sri Lanka have been subjected to a mechanism-based anticancer bioassay employing DNA repair-deficient and repair-proficient yeasts. Of these, seselin [10] and xanthyletin [11] were found to be active. Seselin also exhibited moderate cytotoxicity.