- Semisynthesis
"Semisynthesis" or partial chemical synthesis is a type of
chemical synthesis that uses compounds isolated fromnatural source s (e.g.plant material orbacteria l orcell culture s) as starting materials. These naturalbiomolecule s are usually large and complexmolecule s. This is opposed to atotal synthesis where large molecules are synthesized from a stepwise combination of small and cheap (petrochemical) building blocks.Semisynthesis is usually used when the precursor molecule is too structurally complex, too costly or too inefficient to be produced by
total synthesis . It is also possible that the semisynthetic derivative outperforms the original biomolecule itself with respect to potency, stability or safety.Drugs derived from natural sources are usually produced by harvesting the natural source or through semisynthetic methods: one example is the semisynthesis of
LSD fromergotamine , which is isolated fromergot fungus cultures. The commercial production ofpaclitaxel is also based on semisynthesis (see:paclitaxel total synthesis ).The antimalarial drug
artemether (a component ofCoartem ) is a semisynthetic derived from naturally occurringartemisinin . The latter is unstable due to the presence of alactone group and therefore this group is replaced by anacetal throughorganic reduction with potassium borohydride and methoxylation ["An Improved Manufacturing Process for the Antimalaria Drug Coartem. Part I"Matthias Boehm, Peter C. Fuenfschilling, Matthias Krieger, Ernst Kuesters, and Fritz Struber Org. Process Res. Dev.; 2007; 11(3) pp 336 - 340; (Article) DOI|10.1021/op0602425 ] ::
ee also
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Drug discovery
*Drug development References
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