List of chemical classifications

This is adynamic listand may never be able to satisfy particular standards for completeness. You can help byadding missing itemswithreliable sources.

Chemical classification systems attempt to classifyelementsorcompoundsaccording to certain chemical functional orstructuralproperties. Whereas the structural properties are largelyintrinsic,functional properties and the derived classifications depend to a certain degree on the type ofchemical interactionpartners on which the function is exerted. Sometimes other criteria like purely physical ones (e.g.molecular weight) or – on the other hand – functional properties above the chemical level are also used for building chemicaltaxonomies.

Some systems mix the various levels, resulting in hierarchies where the domains are slightly confused, for example having structural and functional aspects end up on the same level. Whereas chemical function is closely dependent on chemical structure, the situation becomes more involved when e.g.pharmacologicalfunction is integrated, because theQSARcan usually not be directly computed from structural qualities.

Physico-chemical

• bymolecular weight
• byelectrical charge:uncharged, positively, negatively,partially charged
  • formal charge,oxidation state
• solubility
• pH value(orpKAvalue)

Functional

• byfunctional groups
• bybiological activity(mostly appropriate only for large biological molecules (as at least one interacting partner), in particularenzymes,depends on chemical functions of their constituentamino acids)
  • ligandvs.receptor,coenzyme
  • EC number
  • TC number
  • pharmacophorevs. non-drug
• Generalcommercial classification of chemicals

Mixed systems and directories

• Anatomical Therapeutic Chemical Classification System
• Gene Ontology
• Globally Harmonized System of Classification and Labelling of Chemicals
• Chemical Entities of Biological Interest

Historical

• Döbereiner's triads

External links

• Media related toChemical classificationat Wikimedia Commons