Department of Medicinal Chemistry

Research Interests

COBRE CCET

Natural Product Chemistry Research

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Garden to cultivate medicinal potential of plants.

Native medicinal plant project wins Kansas Bioscience Authority funding.

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COBRE Center for Cancer Experimental Therapeutics

Dr. Barbara Timmermann also leads the COBRE initiative for the Center for Cancer Experimental Therapeutics (CCET). Scientific projects at the cutting edge of cancer research, interactions among researchers at the interface of chemistry and biology, and the strong mentoring of junior faculty toward independent careers will contribute to the application for the establishment of a Comprehensive Cancer Center by the National Cancer Institute (NCI) at the University of Kansas Medical Center. The CCET has two scientific Cores.

Core B - High Throughput Screening

The High Throughput Screening (Core B) provides high throughput screening and target identification technology. Using state-of-the-art, automated equipment and a drug-like compound collection of synthetic and natural products, the lab provides a vital tool for biomedical research. The facility is dedicated to providing researchers with high throughput technologies and chemical libraries to assist in identifying biological probes/chemical leads for drug discovery.

Core C - Medicinal Chemistry

The Medicinal Chemistry (Core C) supports the research of all COBRE projects and the High Throughput Screening (HTS) laboratory. Its main role is the design and synthesis of chemical libraries, and large scale production of compounds for screening by the HTS core. The laboratory also conducts the preparation of natural product libraries in appropriate formats for biological screening in cell-free HTS assays. In addition, short courses, workshops and support seminars are conducted for COBRE clients and the core provides in silico guidance to the HTS core.

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Natural Product Chemistry Research

Dr. Timmermann's primary research interests focus on the discovery and biological investigation of novel drug lead compounds from plant and microbial biodiversity, including phenolics, terpenoids, alkaloids, phytoestrogens, and other natural products. Her studies involve evaluating the medicinal importance of these various classes of compounds, including estrogenic, anticancer, anti-oxidant, anti-inflammatory, anti-microbial, and anti-tuberculosis properties. Additionally, the research in her laboratory involves identification of enzymes in the biosynthetic pathway leading to the production of important metabolites; chemical and molecular phylogeny; chemosystematics; chemical ecology; biodiversity prospecting for drug lead discovery, and safety and efficacy studies of botanical dietary supplements with anti-inflammatory activity.

Advanced analytical and medicinal chemistry techniques are employed for drug lead discovery in the Timmermann laboratories, which are housed in the modern Multidisciplinary Resource Building (MRB) on KU's West Campus. Laboratory members employ NMR, MS, and UV spectroscopic techniques, as well as HPLC, GC/MS, LC/MS/MS and other chromatographic methods, for characterization, identification, and purification of novel natural products. Additionally, as part of the KU Medicinal Chemistry Department, Dr. Timmermann's laboratory has access to the state-of-the-art High-Throughput Screening (HTS) laboratory and its expert staff members, who are able to aid in the bioassay-guided isolation of active compounds from natural products.

Dr. Timmermann's interests in botanical dietary supplements and functional foods include the chemical and biological standardization and evaluation of natural product-based botanical medicines. With Complementary and Alternative Medicine (CAM) therapy becoming increasingly popular in the United States and abroad, it is more critical than ever that to evaluate and validate the benefits of supplements and other natural medicines, as well as to provide methods for their standardization. Completed studies include analysis of the anti-cancer effects of catechins from green tea (Camellia sinensis), particularly epigallocatechin gallate (EGCG).

Research by the Timmermann group, in conjunction with the Arizona Center for Phytomedicine Research, includes studies of the anti-inflammatory effects of ginger (Zingiber officinale) and turmeric (Curcuma longa) for the treatment of arthritis, colitis, and other inflammatory diseases. Studies of the characterization, identification, and quantification of constituents within the rhizomes, and the composition of marketed ginger- and turmeric-based dietary supplements, provided standardized material for pre-clinical studies. Further work continues to involve the elucidation of biosynthetic pathways for the gingerols and curcuminoids and both in vitro and in vivo studies of these natural products in models of inflammatory diseases.

Another of Dr. Timmermann's research interests, biodiversity prospecting, offers a valuable opportunity to directly address one of the most important relationships between biodiversity and human health: our dependence on Nature for medicine. Drug lead discovery from natural products, if appropriately designed and carried out, can provide economic incentives for the conservation of the diversity of plants, animals, and microorganisms on Earth. While natural products drug discovery has a long history, the idea that this process could yield conservation and development benefits is relatively new. Dr. Timmermann's research in this area has included bioprospecting in Chile, Argentina, and Mexico through an International Cooperative Biodiversity Group (ICBG) program, where her multidisciplinary and international team of researchers identified a number of novel natural products including the anti-tuberculosis compound saringosterol from Lessonia nigrescens, antibacterial diterpenoid acids from Azorella compacta, and a number of cytotoxic lignans from Larrea tridentata. Future work is projected to include prospecting in other parts of the world, where biodiversity- including a number of species with potential medicinal benefits- is quickly being lost to deforestation and other ecological problems. These projects will continue to focus on drug discovery and conservation of existing biodiversity.

Another area of interest in the Timmermann laboratory is chemical ecology. The viceroy-monarch and viceroy-queen butterfly associations are classic examples of mimicry. These relationships were originally classified as Batesian, or parasitic, but were later reclassified as Mullerian, or mutualistic, based on predator bioassays. The Mullerian reclassification implies that viceroy is unpalatable because it too is chemically defended like the queen and the monarch. However, unlike the queen and the monarch, the viceroy defensive chemistry has remained uncharacterized. We demonstrated that the viceroy butterfly (Limenitis archippus) not only sequesters nonvolatile defensive compounds from its larval host-plant, Carolina willow (Salix caroliniana), but also secretes volatile defensive compounds when disturbed. Our chemical results are consistent with other researchers’ reclassification of the viceroy-queen and viceroy-monarch butterfly as Mullerian. The viceroy butterfly possesses chemical defenses different from its monarch and queen butterfly counterparts (phenolic glycosides vs. cardiac glycosides, respectively), an unusual phenomenon in mimicry warranting future study.