Abstract

Enantiomers differ in absorption rates across membranes, bind with different affinities to plasma proteins, undergo alternative metabolic and detoxification processes and possess distinct binding interactions with their enzyme or receptor targets. Homochiral pharmaceuticals generally display both increased potency and decreased side effects when compared with their racemates. The pharmaceutical industry is taking advantage of the potential financial benefits of homochiral drugs by reinvestigating the enantiomers of chiral racemic drugs and patenting new pharmacological data and production technology for single enantiomers. Differences in the biological activities, pharmacodynamics, pharmacokinetics and metabolism of enantiomeric pairs are briefly reviewed for the following drug classes: antihypertensive agents including -blockers, calcium channel blockers, and angiotensin converting enzyme inhibitors; nonsteroidal antiinflammatory drugs; central nervous system depressant drugs; antimicrobial drugs; opioid analgesic drugs; anticoagulant drugs; neurotransmitters; antineoplastic drugs; and peptidomimetic agents. Methods for the preparation of homochiral drugs, determination of absolute configuration and measurement of enantiomeric purity are discussed.