Journal of Computer-Aided Molecular Design

, Volume 28, Issue 8, pp 795–802 | Cite as

Chemical space networks: a powerful new paradigm for the description of chemical space

  • Gerald M. Maggiora
  • Jürgen BajorathEmail author


The concept of chemical space is playing an increasingly important role in many areas of chemical research, especially medicinal chemistry and chemical biology. It is generally conceived as consisting of numerous compound clusters of varying sizes scattered throughout the space in much the same way as galaxies of stars inhabit our universe. A number of issues associated with this coordinate-based representation are discussed. Not the least of which is the continuous nature of the space, a feature not entirely compatible with the inherently discrete nature of chemical space. Cell-based representations, which are derived from coordinate-based spaces, have also been developed that facilitate a number of chemical informatic activities (e.g., diverse subset selection, filling ‘diversity voids’, and comparing compound collections).These representations generally suffer the ‘curse of dimensionality’. In this work, networks are proposed as an attractive paradigm for representing chemical space since they circumvent many of the issues associated with coordinate- and cell-based representations, including the curse of dimensionality. In addition, their relational structure is entirely compatible with the intrinsic nature of chemical space. A description of the features of these chemical space networks is presented that emphasizes their statistical characteristics and indicates how they are related to various types of network topologies that exhibit random, scale-free, and/or ‘small world’ properties.


Chemical space Molecular representations Descriptor vectors Cell-based methods Molecular networks Chemical space networks 



The authors wish to thank Dr. Vijay Gokhale for reading the manuscript and for his helpful comments and Dr. Dagmar Stumpfe for the design of exemplary network representations and review of the manuscript.


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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  1. 1.University of Arizona BIO5 InstituteTucsonUSA
  2. 2.Translational Genomics Research InstitutePhoenixUSA
  3. 3.Department of Life Science Informatics, B-IT, LIMES Program Unit Chemical Biology and Medicinal ChemistryRheinische Freidrich-Wilhelms-UniversitätBonnGermany

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