Elements of Drug Discovery and Development

In this section we describe some exotic applications of the bioisostery concept implying the utilization of unusual elements such as silicon, boron, selenium, arsenic, and antimony. The use of those elements as bioisosteres of carbon in existing drugs is a different approach enabling the introduction of a new drug-like chemical space into the drug discovery and development process. 

Originating from the academic labs, these methodologies foimd almost immediate use in the pharmaceutical industry and have revolutionized Drug Discovery and Development in the last decades [15]. Indeed, young process chemists can hardly imagine how chemistry was done without Pd, Ni, Rh, or Ru and can hardly conceive of a retrosynthetic analysis without the use of these magic elements. 

Liquid chromatography—mass spectroscopy has become one of the most powerful analytical techniques in the drug discovery and development proeess. LC tandem MS is obviously the technique of choice for the identification of metabolites as illustrated in this chapter. Exact mass measurements and elemental composition assignment are essential for the characterization of the metabolites. Accurate mass measurements of the product ions, formed in an MS/MS experiment, greatly facilitate the structure elucidation of the metabolites. With the ever evolving technological advances in mass spectrometry and separation science, LC MS will continue to play an important role in metabolite identification in the future. 

---