Description of drugs, particularly antibiotics, that are derived from natural products via chemical modification in the laboratory.
Semisynthetic drugs are not limited antibiotics, which otherwise are of microorganism origin, but can include any bioactive substance that is available in some quantity and, of course, chemically modifiable. The reason for taking this route towards synthesis is a combination of the utility of modifying drug chemical properties and the difficulties of synthesizing especially complex molecules from scratch.
The chemical modification of semisynthetic drugs is towards thwarting bacterial mechanisms of antibiotic resistance, to increase ability to penetrate into bacterial cells (thereby expanding spectrum of activity), to increase the potential for absorption into the body (such as by resisting acid lability during passage through the stomach), to increase persistence in the body, etc. In short, modifying drugs can give them a "new lease on life" and with semisynthetic drugs it is an otherwise natural product that is being modified.
For more on this topic, see Wikipedia and Google. Contact web master. Return to home.
