Ranjala Ratnayake, Ph.D.

Ranjala Ratnayake

Research Assistant Professor

Medicinal Chemistry


EMAIL: rratnayake@cop.ufl.edu

PHONE: 352-627-9220



  • Ph.D., University of Queensland, Australia
  • MPhil, The Open University of Sri Lanka
  • BSc, The Open University of Sri Lanka

Biographical Sketch

Ranjala Ratnayake, Ph.D., was appointed a research assistant professor in the department of medicinal chemistry at the University of Florida College of Pharmacy in February 2017. Ratnayake previously served as an assistant scientist in the department since 2014, and completed her postdoctoral training at UF from 2009-11, under the supervision of Hendrik Luesch, Ph.D., a professor and chair of medicinal chemistry and the Debbie and Sylvia DeSantis Chair in Natural Products Drug Discovery and Development. As an experienced researcher in natural product chemistry, analytical techniques and mass spectrometry, as well as chemical library screening, she leads efforts to find new drug therapies and identify new drug cancer treatments at the UF College of Pharmacy’s Center for Natural Products, Drug Discovery and Development, or CNPD3. In 2016, she was awarded a National Cancer Institute Research Specialist Award to develop complex natural products libraries and multidimensional screening platforms to support drug discovery efforts at UF.

In addition to her postdoctoral fellowship at UF, Ratnayake completed an initial postdoctoral training at the National Cancer Institute and the Institute for Molecular Biosciences in Australia. She graduated in 2007 with her doctoral degree in organic chemistry from the University of Queensland in Australia. She earned a master of philosophy and bachelor of science degree from The Open University in her native country of Sri Lanka.


  • American Society of Pharmacognosy (ASP)
  • Royal Australian Chemical Institute (RACI)
  • Chartered Chemist (C. Chem), Institute of Chemistry Ceylon (Sri Lanka)
  • Sri Lanka Association for the Advancement of Science (SLAAS)

Research Interests

  • Drug discovery and development
  • Natural product chemistry

Recent Publications

Caldoramide, a Modified Pentapeptide from the Marine Cyanobacterium Caldora penicillata. Gunasekera SP, Imperial L, Garst C, Ratnayake R, Dang LH, Paul VJ, Luesch H. J Nat Prod. 2016, 79(7):1867-71.

Tasiamide F, a potent inhibitor of cathepsins D and E from a marine cyanobacterium. Al-Awadhi FH, Ratnayake R, Paul VJ, Luesch H. Bioorg Med Chem. 2016,24(15):3276-82.

Discovery, Total Synthesis and Key Structural Elements for the Immunosuppressive Activity of Cocosolide, a Symmetrical Glycosylated Macrolide Dimer from Marine Cyanobacteria. Gunasekera SP, Li Y, Ratnayake R, Luo D, Lo J, Reibenspies JH, Xu Z, Clare-Salzler MJ, Ye T, Paul VJ, Luesch H. Chemistry. 2016, 22(24):8158-66.

Englerin A Inhibits EWS-FLI1 DNA Binding in Ewing Sarcoma Cells. Caropreso V, Darvishi E, Turbyville TJ, Ratnayake R, Grohar PJ, McMahon JB, Woldemichael GM. J Biol Chem. 2016, 6;291(19):10058-66.

Multidimensional Screening Platform for Simultaneously Targeting Oncogenic KRAS and Hypoxia-Inducible Factors Pathways in Colorectal Cancer. Bousquet MS, Ma JJ, Ratnayake R, Havre PA, Yao J, Dang NH, Paul VJ, Carney TJ, Dang LH, Luesch H. ACS Chem Biol. 2016, 11(5):1322-31

C3 and 2D C3 Marfey’s Methods for Amino Acid Analysis in Natural Products. Vijayasarathy S, Prasad P, Fremlin LJ, Ratnayake R, Salim AA, Khalil Z, Capon RJ. J Nat Prod. 2016, 79(2):421-7.

Grassypeptolides as natural inhibitors of dipeptidyl peptidase 8 and T-cell activation. Kwan JC, Liu Y, Ratnayake R, Hatano R, Kuribara A, Morimoto C, Ohnuma K, Paul VJ, Ye T, Luesch H. Chembiochem. 2014, 15(6):799-804.

Cultivated sea lettuce is a multiorgan protector from oxidative and inflammatory stress by enhancing the endogenous antioxidant defence system. Ratnayake R, Liu Y, Paul VJ, Luesch H, Cancer Prev Res (Phila). 2013, 6(9): 989-99

Englerin A stimulates PKCθ to inhibit insulin signalling and to simultaneously activate HSF1: pharmacologically induced synthetic lethality. Sourbier C, Scroggins BT, Ratnayake R, Prince TL, Lee S, Lee MJ, Nagy PL, Lee YH, Trepel JB, Beutler JA, Linehan WM, Neckers L. Cancer Cell. 2013, 23(2): 228-37.

Flabelliferins A and B, sesterterpenoids from the South Pacific sponge Carteriospongia flabellifera. Diyabalanage T, Ratnayake R, Bokesch HR, Ransom T, Henrich CJ, Beutler JA, McMahon JB, Gustafson KR, J Nat Prod. 2012, 75(8): 1490-4