Chemical Terms

Chemaxon's Chemical Terms is a language for adding advanced chemical intelligence to cheminformatics applications. Chemical Terms provides chemistry and mathematical functions including property predictions, functional group recognition, isomer enumeration, conformer selection, ring and distance based topological functions, and other electronical, steric and structural functions.

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The functions are integrated via an open plugin interface providing dynamic loading, easy extension and programmatic access. The Chemical Terms expressions are understandable and easily modifiable. Some application examples:

Search filters calculated on the fly:

(heteroAromaticRingCount() < 4) &&
(rotatableBondCount() <= 10);

Calculated properties stored in a database column:

(mass() <= 500) &&
(logP() <= 5) &&
(donorCount() <= 5) &&
(acceptorCount() <= 10)

Goal function for random evolutionary drug design:

dissimilarity("ChemicalFingerprint", actives) -
dissimilarity("PharmacophoreFingerprint", actives) > 0.6

Reactitvity rule for determine activated ring systems in a virtual a reaction:

charge(ratom(1), "aromaticsystem") <= -0.2


Chemical Terms expressions can be used in various ChemAxon applications including JChem Base, JChem Cartridge, Instant JChem, Reactor, Screen, etc., in custom applications via the API, or from command line using the "evaluate" tool.

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