Chemical Structures and Classification of Antimicrobial Drugs

This chapter aims to review the literature on anti-infective (also known as antimicrobial) drugs among the anti-infections drugs, and to highlight recent developments relating to novel antibiotics and their classification. Antibiotic classification is determined according to their structure and mechanism of action; the main groups include β-lactams, macrolides, fluoroquinolones, tetracyclines, and aminoglycosides. Despite significant progress in anti-infective therapies, infectious diseases caused by bacteria and fungi remain a major worldwide health problem due to the rapid development of resistance to existing drugs. This resistance increasingly limits the effectiveness of current anti-infective drugs. To overcome this problem, scientists are searching for novel therapeutic agents that are efficacious against microorganisms and cause limited side-effects. Naturally occuring compounds in plants have previously been used successfully to treat many types of infection and illness. For this reason, it is quite important to understand the chemical composition of natural products and their mechanisms of action, in order to synthesize semi-synthetic or synthetic anti-infective drugs. Indeed, many chemically synthesized drugs originated from natural sources, e.g. aspirin (willow plant), opioids such as morphine (opium poppy), atropine (Atropa belladonna), and quinine (cinchona). Therefore, nature is a very fruitful source for pharmacy, medicine, biology and chemistry students.

Keywords: Anti-bacterial drugs, Aminoglycosides, Anti-fungal drugs, Antiinfective agents, Antibiotic, Cephalosporins, Chloramphenicol, Classification of antibiotics, Drug research, Drug resistance, Fluoroquinolones, Infectious diseases, Macrolides, Microorganisms, Natural products, Penicillin, Penicillium species, Synthesis, Tetracyclines, β-lactams.