Biologically Relevant Heterocyclic Compounds

Heterocyclic chemistry is a rapidly growing branch of organic chemistry. While it was estimated that original research papers in heterocyclic chemistry published before 1982 constituted about 40% of organic chemistry literature [1], the number increased to more than 60% in 1998 [2]. This explosive growth is even greater when one considers research with heterocyclic compounds published in bioorganic, biophysical, pharmaceutical, and medicinal journals, among others. It is of interest, therefore, to publish this special issue of Molecules devoted to biologically relevant heterocyclic compounds. In keeping with the high standards of this journal, the topics of the contributions selected, both reviews and original research papers, illustrate the general trends in current research. These include the development of novel synthetic methods, the rational design and synthesis of new drugs that target specific biological receptors, and the application of heterocyclic compounds as probes for biomolecules in biophysical and bioanalytical chemistry. I wish to thank the authors for their outstanding cooperation and support in putting this issue together.