Plant sources drug development

The drug development process starts with the synthesis of novel chemical compounds. Substances with complex structures may be obtained from various sources, e.g., plants (cardiac glycosides), animal tissues (heparin), microbial cultures (penicillin G) or cultures of human cells (urokinase), or by means of gene technology (human insulin). As more insight is gained into structure-activity relationships, the search for new agents becomes more clearly focused. 

In view of these developments, one must be somewhat pessimistic about the future of cinchona alkaloids and other plant products in the treatment of malaria. Certainly the extensive researches on cinchona alkaloids offer little hope that an improved drug will be found in this field. The situation with respect to development of better antimalarials from other plant sources seems to be even less hopeful. 

Natural products have been used as therapeutic agents or medicinal products for millennia in one form or another and a huge number of these, especially prior to the last 50 years, are derived from plants [2]. Today, natural products derived from plant sources continue to play a vital role in the treatment of diseases. There are many examples where the active compound in plant-derived traditional medicines has been used as a pharmaceutical agent. A particularly important example is the discoveiy and development of anti-malarial drugs such as quinine and artemisinin (Fig. 1.3). Quinine was isolated as early as 1820 and was used extensively until the... 

The advent of electrospray ionization certainly opened many new application areas for mass spec-trometric analysis. This is based on the ability to provide extreme soft liquid-based ionization. Perhaps the most important application area is the analysis of peptides and proteins. The possibility to perform rapid molecular-weight determination of proteins up to 200 kDa stimulated the commercial availability of MS instrumentation featuring atmospheric-pressure ion sources, equipped with electrospray ionization. Other application areas benefited from these developments. LC-MS has become an important analytical tool in many areas of drug development within the pharmaceutical industry, in the study of natural products in plants, in food and environmental analysis. It is about to enter the clinical application area for therapeutic drug monitoring, systematic toxicological analysis, and monitoring of inherited metabolic diseases. 

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