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Searching SciFinder

SciFinder: A CAS Solution

Databases Covered

Chemical Abstracts

Chemical Abstracts is comprised of the CAS REGISTRY database of substances and the CAplus database of references.


    • Organic and inorganic substances.  As of 2018, there were over 143 million substances, with more being indexed every day; click here for the most up-to-date numbers.

    • More than 67 million sequences ; click here for the most up-to-date numbers.

    • Contains Information on different substances;

      • Synonyms​

      • Molecular formulae 

      • Ring analysis data

      • Structure diagrams

      • Experimental and predicted property data

      • Literature references

  • CAplus

Chemical identifiers used by Chemical Abstracts

  • CAS REGISTRY Number-  a unique numerical identifier assigned by Chemical Abstracts Service to every chemical substance described in the open scientific literature.  It consists of three sets of digits separated by hyphens.

  • CAS index nameA unique name assigned to the substance by the Chemical Abstracting Service, according to their rules of nomenclature

  • Chemical Structure- using the Java or Non-java editor users can draw the chemical structure

  • Molecular Formulaformula giving the number of atoms of each of the elements present in one molecule of a specific compound.

    • Note: large biomacromolecules, protein sequences, and polymers may not have a molecular formula

  • Other Names- Synonyms for the compound may include trade names and common names

  • Properties- experimental and calculated physical properties, complete with references


MEDLINE is a database created by the National Library of Medicine (NLM) in 1966.

  • More than 25.3 million records 

  • More than 5,600 biomedical and related health sciences journals (including chemistry and biochemistry),

  • Covers from1946 to today in medicine, medicinal chemistry, biology, biochemistry, and bioengineering

  • Updated with new information daily 

Sources for Medline include

  • About 5,300 journals

  • Citations from Index Medicus

  • Index to Dental Literature

  • HealthSTAR database

  • International Nursing Index


  • ​Data from NLM's Cumulated Index Medicus (CIM) (1960 through 1965)

  • Current List to Medical Literature (1949 through 1959)

How to search MEDLINE:

  • Medical Subject Headings: MeSH is the controlled vocabulary created by the U.S. National Library.  It is not directly searchable in SciFinder, but MeSH terms are hot-linked in the indexing of the references and can be clicked to acquire all other references containing that term.

  • List of Serials Indexed for Online Users: provides bibliographic information for all journals whose articles are indexed in MEDLINE

  • Substance Searching: It is possible to search by substance identifier to retrieve articles that include substances of interest. You can specify an exact structure, a substructure, or a similarity structure, or you can search by substance identifier or molecular formula.  Note that NLM only began adding CAS REGISTRY numbers to the indexing of MEDLINE articles in 1986; if you wish to locate older articles that reference a substance of interest, you should search for its name as a topic.

  • Research Topic or Author Searching: Both topic and author searches will return MEDLINE results.  For best results, use only author initials when searching to retrieve MEDLINE references.


ChemZent provides access to the Chemisches Zentralblatt database, a historic collection of German-language abstracts to literature published between 1830 and 1969.  Each record in the database includes a machine translation of the title and the abstract into English (some translations are better than others), as well as a link back to the original German-language abstract within a scan of the Chemisches Zentralblatt issue in which it was indexed.  ChemZent records include indexed substances and reactions.


CASREACT searches a graphical database of reactions that have appeared in the literature since 1840.

  • More than 106 million single and multi-step reactions, as of 2018

  • More than 14 million synthetic preparations

  • Records include:

    • Structure diagrams for reactants and products

    • CAS Registry Numbers for all reactants, products, reagents, solvents, and catalysts

    • Detailed reaction conditions

    • Experimental procedures

How to search CASREACT

  • By Reaction: Draw a partial or complete reaction into the structure editor, and click Get Reactions.

  • By Chemical Structure: From a list of substances, click on Get Reactions, and specify the reaction role that the substances are to play.  Currently, this is the only way to search for a substance used as a solvent or catalyst in a reaction.

  • Explore by Topic or Explore by Author: From a list of references, click on Get Reactions.  This will retrieve all reactions indexed from each document.

For the latest statistics, see


CHEMCATS is a commercial availability database linked to the Registry database.

  • Millions of commercially available products

  • Millions of unique CAS Registry Numbers

  • Information about commercially available chemicals and their suppliers:

    • CAS Registry Number 

    • Supplier information

    • Quantities

    • Prices ( not all companies supply price and size)

    • Entries are provided by the chemical suppliers and should be taken on an "as-is" basis

    • You can customize the view to prioritize preferred vendors.

How to search CHEMCATS

  • By Chemical Stucture:  Substances with an orange flask beside them have commercial availability available.  To get availability for an entire set of substances, click Get Commercial Sources.

  • By Reaction: From a reaction result, mouse over a substance, and click on the double arrow to see if commercial sources are present for the substance.

For the latest statistics, see


CHEMLIST substances that are regulated by state, federal and international agencies, including EINECS (European Inventory of Existing Commercial Chemical Substances) and TSCA (Toxic Substances Control Act (TSCA) Inventory.

  • More than 346,000 inventoried or regulated chemicals

  • Information on regulated chemical substances

    • Chemical names

    • Synonyms

    • Regulatory lists

    • Chemical inventory status 

Unfortunately, the database only lists the appropriate sections of the various regulations and does not, for the most part, contain the applicable text.

How to Search CHEMLIST

  • By Chemical Stucture: The regulated substances information will appear within the full view of the substance record.
  • By Reaction: Draw a partial or complete reaction into the structure editor, and click Get Reactions.  From the reaction record, mouse over any substance and click on the double arrow button to see if it has regulatory information in its record.

For the latest statistics, see

Screen shots throughout this guide are taken from SciFinder and are used with permission from CAS. Copyright 2020 American Chemical Society, all rights reserved.

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