Comprehensive virtual reactions to explore the available chemical space at large scale.


Generate chemically feasible products

Based on defined reaction schemas Reactor performs virtual reactions on a large number of reactants and generates the corresponding products. Detailed reaction scheme definition enables incorporating organic chemistry knowledge to guide the virtual enumeration. The application is available in the form of a Desktop application, Command Line Tool, in workflow tools (KNIME, Pipeline Pilot) and as Java or REST API for programmatic access.

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Reaction synthesis on your desktop

Reactor is a high performance, integrable reaction enumeration engine. It works with generic reaction equations that can be drawn in Marvin or defined and imported in various different formats, including among others: SMIRKS/SMARTS strings, RDF, RXN and MRV files. The Reactor package includes a large and continuously growing library of organic chemical reactions that can be utilized directly, without any further configuration.


Define your chemical reactions

By using generic reaction equations, virtual synthetic compound libraries can be generated under full manual control. Therefore, users have the opportunity to draw and edit reactants directly, and to select chemically meaningful products from the output of the enumeration process - by using their chemical intuition on the fly. This approach is particularly advantageous for enumerating small, focused libraries.


Get synthesizable molecules by proper reaction rules

The reaction rules are defined in Chemical Terms, Chemaxon’s scripting language that is designed to add chemical intelligence to cheminformatics applications. Through Chemical Terms a large number of calculated properties can be included in the reaction rules to produce valid compound libraries. Besides calculating physicochemical properties on-the-fly, the Chemical Terms language also supports importing arbitrary fields from the input reactant files used in the evaluation of the reaction rules.


Stereochemically aware reactions

Reaction schemes can include stereochemical information. Reactor is capable of handling both tetrahedral and double bond stereochemistry flexibly. In addition, inversion and retention centers, as well as cis-trans configuration changes can be determined within Reactor’s smart reaction schemes. Prochiral reaction schemes are also supported since version 5.5, allowing the user to manage syn/anti additions.


Library design

Reactor can be set up to carry out simple sequential enumeration, in which case reactants are virtually reacted with each other in the order they are present in the input files. Reactor is also capable of combinatorial enumeration, generating combinatorial virtual synthetic libraries. Users also have the option to exclude unwanted products from the enumeration results manually, restricting the outcome of the reaction enumeration process to the desired main products. Reactor supports the generation of product or reaction libraries in a large variety of different output formats.

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Create rich molecular libraries

Reactor has the option to copy arbitrary property fields from the input reactant files to the results. These can include e.g. solubility or availability information of the reactants. Also, Reactor can generate synthesis codes for each reaction in the enumeration process containing selected information from the reaction scheme and the reactants.


A wizard-like user interface

The standalone version of Reactor has a clean and straightforward graphical user interface for reaction enumeration process configuration. The GUI leads users step by step through the whole configuration process of the virtual chemical reaction.


Accessibility on various platforms

Reactor is available as a standalone application, as well as integrated into Instant JChem, JChem Microservices, JChem for Office, and workflow management tools KNIME and Pipeline Pilot. In its standalone version, it can be used as a GUI application, as a command line application, and also as a full-featured Java API. Reactor is platform-independent, it is available on Windows, Mac OS and Linux systems.

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Create and test your reactions

Reactor has an integrated reaction sketcher and editor tool. Users can create their own reaction schemes and add corresponding reaction rules by using the Chemical Terms language. The created reaction schemes can be easily tested and the reaction rules can be validated using the integrated reaction testing tool in Reactor.

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