Inchemistry, aderivative is acompound that isderived from a similar compound by achemical reaction.
In the past, derivative also meant a compound thatcan be imagined to arise from another compound, if oneatom orgroup of atoms is replaced with another atom or group of atoms,[1] but modern chemical language now uses the termstructural analog for this meaning, thus eliminating ambiguity.[citation needed] The term "structural analogue" is common inorganic chemistry.
Inbiochemistry, the word is used for compounds that at least theoretically can be formed from theprecursor compound.[2]
Chemical derivatives may be used to facilitate analysis. For example,melting point (MP) analysis can assist in identification of many organic compounds. A crystalline derivative may be prepared, such as asemicarbazone or2,4-dinitrophenylhydrazone (derived fromaldehydes orketones), as a simple way of verifying the identity of the original compound, assuming that a table of derivative MP values is available.[3] Prior to the advent ofspectroscopic analysis, such methods were widely used.
Inanalytical chemistry,derivatization can be used to convertanalytes into other species for improving detection. For example,polar groups such asN-H orO-H can be converted into less polar groups. This reaction reduces theboiling point of the molecule, allowing non-volatile compounds to be analyzed bygas chromatography.[4]