The Chemical Thesaurus
Reaction Chemistry Database

The Chemical Thesaurus reaction chemistry database was originally developed to store data about Lewis acids, Lewis bases and Lewis acid/base complexes, but it has now grown into something far, far larger.


A thesaurus – from the Greek – is a storehouse, and the Chemical Thesaurus is a storehouse of information about chemical species and chemical interactions and reactions. The software behaves rather like the thesaurus built into your word processor which allows you to jump from word to word to word by meaning:

happy    delighted    wild    savage   
                                     crude    raw    uncooked...

Likewise, the chemical thesaurus allows you to move from chemical species to chemical species (via their chemical reactions):

natural gas    methane    hydrogen cyanide    
                                        adiponitrile    1,6-diaminohexane    nylon-6,6

The software uses a relational database to store information about any chemical reaction process, including:

Phase change
Resonance structure interconversion
Interchanging conformation
Single electron transfer
Substitution-transfer-abstraction-displacement (STAD)
Redox reactions
Multi-step mechanisms
Synthetic pathways
Simple (non-feedback controlled) biosynthetic pathways
etc., etc., etc.

The application software is extensively hyper-linked. Just click around, explore, discover... Learn how the application works.

It is not possible to add all chemistry to any one database. The decision has therefore been made to fill The Chemical Thesaurus with as much fundamental chemistry as possible. It is hoped that the database contains all of the reaction chemistry knowledge that a chemistry major would be expected to be familiar, specialist modules excepted.

The present version has good coverage of:

Isotopes and major decay pathways
The periodic table
Atomic ions
Main group chemistry
Organic chemistry expressed in terms of generic functional group reactions
Industrial chemistry

There are 100 hydrogen reactions and more than 500 for water

No other chemistry database provides access to this type of chemical information.

Although the database does have references to the primary and secondary literature, the data is mainly at textbook level. However, this should be seen as a strength, not a weakness because The Chemical Thesaurus attempts to model reaction chemistry space from the ground up.

K.R. Cousins reviewed version 2.0 of the software for the Journal of the American Chemistry Society: JACS 123, 35, pp 8645-6 (2001). Her review starts:

"The Chemical Thesaurus is a reaction chemistry information system that extends traditional references by providing hyperlinks between related information. This program goes a long way toward meeting its ambitious goal of creating a non-linear reference for reaction information. With its built-in connections, organizing themes, and multiple ways to sort and view data, The Chemical Thesaurus is much greater than the sum of the data in its database. The program does an excellent job of removing the artificial barriers between different subdisciplinary areas of chemistry by presenting a unified vision of inorganic and organic reaction chemistry."

The Chemical Thesaurus cannot compete with the major on-line reaction chemistry databases such as Beilstein, Gmelin and CAS in terms of numbers of data items, and it does not attempt to.

Go to The Chemical Thesaurus

Chemogenesis Paper

© Mark R. Leach 1999-

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