Dr Sunny Sunassee
- Natural Products Discovery
- Marine Natural Products Chemistry (invertebrates, algae, micro-organisms)
- Plant Natural Products Chemistry
- Synthetic Organic chemistry
- Medicinal Chemistry
With the problems associated with an increasing incidence of cancer in an ageing society, the steady spread of HIV-AIDS, malaria and other diseases along with a growing resistance to current antibiotics, there is a continuous need for new and more effective drugs.
Natural products chemistry is a principal area of research at the interface of the fields of chemistry and biology, accounting for at least 50% of all approved drugs on the market. Ongoing drug discovery research requires a constantly expanding library of compounds with a wide range of molecular and chemical diversity. This is mainly achieved through the isolation of novel natural products, also known as secondary metabolites.
What are natural products and why study them? According to this editorial published in 2007 in Nature Chemical Biology, the simplest definition for a natural product is a small molecule that is produced by a biological source. The isolation and identification of these secondary metabolites by marine natural product chemists over the last three decades has provided important lead compounds for the discovery of new pharmaceuticals, especially anti-cancer drugs such as Halaven®, Adcetris® and Yondelis®.
Adcetris® originates from the MNP Dolastatin 10 which
was isolated from the sea hare Dolabella auriculari,
collected off the west coast of Mauritius in the early 1970’s
Yondelis® was originally isolated from the
Caribbean marine ascidian Ecteinascidia turbinate
Halaven® originates from the MNP Halichondrin B that was isolated from the marine sponge genus Halicondria.
The main objective of our research is to discover new chemical entities isolated from southern African marine organisms (invertebrates, algae and microbes) which may show potential pharmaceutical applications.
Below are some examples of South African Marine Natural Products (MNP) that have previously been patented for various anticancer properties. These examples also highlight the range chemical and structural diversity that is inherent to marine invertebrates.
We are interested in modern applications of Marine Natural Products (MNP) chemistry, which involves the isolation and structure elucidation of novel and/or bioactive organic compounds produced by various marine organisms (invertebrates, algae, micro-organisms). The structures of these new organic molecules are elucidated mainly by standard spectroscopic analyses such as 1D and 2D NMR (Nuclear Magnetic Resonance) experiments, UV/Vis, Infra-Red and Mass Spectrometry.
Biological Target Areas
Our research efforts are directed towards the discovery of natural products (and their synthetic analogues) that show promising activity against infectious diseases, pathogenic bacteria and non-communicable diseases such as cancer.
We have a very strong interest in finding new and more effective chemotherapeutic agents against various types of cancers. Additionally, by using compounds with distinctive mechanisms, we aim to further our basic biological and biochemical understanding different modes of action of cancer.
- Infectious Diseases
Our research group also has an interest in discovering new lead compounds against a range of infectious diseases, such as malaria, TB and HIV/AIDS. The Marine Natural Products research programme runs in accordance with the current focus areas of the MRC Drug Discovery Unit at UCT.