Cited by 720Computational Drug Discovery MethodsSynthesis and Characterization of Heterocyclic CompoundsHistory and advancements in chemistry

The Chemical Space Project

Open access
Reymond, Jean-Louis·2015·Accounts of Chemical Research

Abstract

One of the simplest questions that can be asked about molecular diversity is how many organic molecules are possible in total? To answer this question, my research group has computationally enumerated all possible organic molecules up to a certain size to gain an unbiased insight into the entire chemical space. Our latest database, GDB-17, contains 166.4 billion molecules of up to 17 atoms of C, N, O, S, and halogens, by far the largest small molecule database reported to date. Molecules allowed by valency rules but unstable or nonsynthesizable due to strained topologies or reactive functional groups were not considered, which reduced the enumeration by at least 10 orders of magnitude and was essential to arrive at a manageable database size. Despite these restrictions, GDB-17 is highly relevant with respect to known molecules. Beyond enumeration, understanding and exploiting GDBs (generated databases) led us to develop methods for virtual screening and visualization of very large databases in the form of a "periodic system of molecules" comprising six different fingerprint spaces, with web-browsers for nearest neighbor searches, and the MQN- and SMIfp-Mapplet application for exploring color-coded principal component maps of GDB and other large databases. Proof-of-concept applications of GDB for drug discovery were realized by combining virtual screening with chemical synthesis and activity testing for neurotransmitter receptor and transporter ligands. One surprising lesson from using GDB for drug analog searches is the incredible depth of chemical space, that is, the fact that millions of very close analogs of any molecule can be readily identified by nearest-neighbor searches in the MQN-space of the various GDBs. The chemical space project has opened an unprecedented door on chemical diversity. Ongoing and yet unmet challenges concern enumerating molecules beyond 17 atoms and synthesizing GDB molecules with innovative scaffolds and pharmacophores.

Integrity signals

Registry

Crossref · 10.1021/ar500432k

Cites

98 of 98 references verified0 citation errors · 0 not checkable

Statistics

Recomputing p-values needs the paper’s full text.

Claims the paper makes

We couldn’t retrieve this paper’s full text, so its claims and self-check weren’t run. The registry and citation checks still apply.

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Training sets for conventional QSAR models do not exceed millions of entries, while the estimated size of drug-like chemical space is up to 10^60 molecules.

    “To conclude this section, we note that training sets used to develop conventional QSAR models do not exceed millions of entries, while the estimated size of drug-like chemical space is up to 1060 molecules.123”

    From QSAR without borders (2020) · cites this paper as [123]

  • Public databases contain experimentally determined bioactivity data for about a million molecules, which represent only a small percentage of commercially available compounds and a negligible fraction of the synthetically accessible chemical space.

    “Currently, public databases contain experimentally determined bioactivity data for about a million molecules, which represent only a small percentage of commercially available compounds6 and a negligible fraction of the synthetically accessible chemical space7.”

Cites

Flagged first, then by citations

Cited by

Sorted by citations

Authors
Reymond, J.-L.
Affiliations
University of Bern (CH)
Corresponding author
Reymond, Jean-Louis
Venue
Accounts of Chemical Research
Published
2015-02-17
Volume
48
Issue
3
Pages
722-730
ISSN
  • 0001-4842 (ISSN-L)
  • 1520-4898
OpenAlex
W1992156271
Cited by
720
References
98
Citations by year
2026: 87 · 2025: 94 · 2024: 90 · 2023: 80 · 2022: 62 · 2021: 60 · 2020: 67 · 2019: 59 · 2018: 35 · 2017: 44 · 2016: 31 · 2015: 10
FWCI
41.56
Type
journal article
Language
en
Open access
Locations
  • Accounts of Chemical Research (publishedVersion, other-oa)
  • PubMed (publishedVersion)
  • BORIS (University Library Bern) (submittedVersion, other-oa)
  • Open Access CRIS of the University of Bern
Funders
Swiss National Science Foundation
Topics
  • Physical Sciences › Computer Science › Computational Theory and Mathematics › Computational Drug Discovery Methods
  • Physical Sciences › Chemistry › Organic Chemistry › Synthesis and Characterization of Heterocyclic Compounds
  • Physical Sciences › Chemistry › Physical and Theoretical Chemistry › History and advancements in chemistry
Keywords
chemical space, virtual screening, molecular fingerprints, nearest neighbor search, drug discovery, chemical diversity

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review