In
chemistry, a derivative is a
compound that is
derived from a similar compound by a
chemical reaction
A chemical reaction is a process that leads to the chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and break ...
.
In the past, derivative also meant a compound that ''can be imagined to'' arise from another compound, if one
atom
Every atom is composed of a nucleus and one or more electrons bound to the nucleus. The nucleus is made of one or more protons and a number of neutrons. Only the most common variety of hydrogen has no neutrons.
Every solid, liquid, gas ...
or
group of atoms is replaced with another atom or group of atoms,
but modern chemical language now uses the term
structural analog for this meaning, thus eliminating ambiguity. The term "structural analogue" is common in
organic chemistry
Organic chemistry is a subdiscipline within chemistry involving the science, scientific study of the structure, properties, and reactions of organic compounds and organic materials, i.e., matter in its various forms that contain carbon atoms.Clay ...
.
In
biochemistry
Biochemistry or biological chemistry is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology ...
, the word is used for compounds that at least theoretically can be formed from the
precursor compound.
Chemical derivatives may be used to facilitate analysis. For example,
melting point
The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends ...
(MP) analysis can assist in identification of many organic compounds. A crystalline derivative may be prepared, such as a
semicarbazone or
2,4-dinitrophenylhydrazone
2,4-Dinitrophenylhydrazine (2,4-DNPH or DNPH) is the organic compound C6H3(NO2)2NHNH2. DNPH is a red to orange solid. It is a substituted hydrazine. The solid is relatively sensitive to shock and friction. For this reason DNPH is usually handled a ...
(derived from
aldehyde
In organic chemistry, an aldehyde () is an organic compound containing a functional group with the structure . The functional group itself (without the "R" side chain) can be referred to as an aldehyde but can also be classified as a formyl group ...
s or
ketone
In organic chemistry, a ketone is a functional group with the structure R–C(=O)–R', where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group –C(=O)– (which contains a carbon-oxygen double bon ...
s), as a simple way of verifying the identity of the original compound, assuming that a table of derivative MP values is available.
Prior to the advent of
spectroscopic analysis, such methods were widely used.
See also
*
Derivatization
*
Precursor (chemistry)
In chemistry, a precursor is a compound that participates in a chemical reaction that produces another compound.
In biochemistry, the term "precursor" often refers more specifically to a chemical compound preceding another in a metabolic pathway ...
*
Product (chemistry)
Products are the species formed from chemical reactions. During a chemical reaction, reactants are transformed into products after passing through a high energy transition state. This process results in the consumption of the reactants. It can be ...
*
Structural analog
References
Chemical compounds
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