Preface [Hot Topic: Biological Inhibitors (Executive Editors: Atta-ur-Rahman / M. Iqbal Choudhary)]

Understanding disease mechanisms at a molecular level and designing or discovering appropriate molecular entities through this understanding is an important approach to modern drug discovery. Ligands that can inhibit biochemical targets such as enzymes or receptors are specially important in this regard. Over 30% of drugs currently used are the inhibitors of enzymes and other receptors. This issue of Mini-Reviews in Medicinal Chemistry contains several good articles, contributed by leading experts on biological inhibitors. The review by Rossi and Zavalloni describes the progress made in the development of inhibitors of glycoprotein IIb / IIIa (GP IIb / IIIa) receptor, which is involved in platelet aggregation. Reszka and Rodan have reviewed the role of nitrogen-containing biophosphonate in the prevention of spinal and non-vertebral osteoporotic fractures, involving the inhibition of a key biosynthetic enzyme, farnesyl diphosphate synthase, which catalyzes the synthesis of 15-carbon isoprene moiety, farnesyl disphosphate. The isoprene moiety plays an important role in the biosynthesis of several regulatory proteins involved in the bone-resorbing osteoclast inhibition of serine proteases of eukaryotic and prokaryotic origins, which has been reviewed by Konaklieva and Plotkin. Serine proteases are involved in a variety of health disorders, such as pulmonary hypertension, destruction of the lung parenchyma in emphysema, as well as in resistance of bacteria to β-lactam antibiotics. A review by Miljkovic et al. focuses on the inhibition of nitric oxide synthase by mycophenolic acid. NO is synthesized from Larginine by intracellular enzyme NO synthase, while NO- is involved in immune response of an organism and in a multitude of other biochemical functions. Abell et al. have presented various inhibitors developed in recent years against types I and II 3- dehydroquinate dehydratase enzymes involved in shikimate and quiate pathways. Guerrero and Rosell in review the contribution of enzyme inhibitors in biorational approaches for pest control: another important application of enzyme inhibition strategy. These targeted enzymes are involved in normal physiology and reproduction of insect pests, and their disruption effects the life cycle of insects. ŧren et al. review the properties of matrix metalloproteinases and their role in the pathogenesis of intestinal anastomotic dehiscence. This review also contains a wealth of information about synthetic metalloproteinase inhibitors. Along with this three other general reviews have also been included in this issue of MRMC. It is hoped that these reviews from leading authorities will be of great interest to medicinal chemists as well as to researchers involved in drug development and discovery programs of pharmaceutical industries and R & D institutions.