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Fact Sheet
ChemIDplus

ChemIDplus is a free, web-based search system that provides access to structure and nomenclature authority files used for the identification of chemical substances cited in National Library of Medicine (NLM) databases. ChemIDplus also provides structure searching and direct links to many biomedical resources at NLM and on the Internet for chemicals of interest. The database contains over 368,000 chemical records, of which over 206,000 include chemical structures, and is searchable by Name, Synonym, CAS Registry Number, Molecular Formula, Classification Code, Locator Code, and Structure.

A new ChemIDplus Lite version is available for Name and RN searching without the need for plugins or applets.

Web Access/Searching

To use ChemIDplus, you will need a web browser that provides the capabilities needed to accept a structure query into the Chime plug-in which allows you to view the structures. A compatible structure drawing package such as ISIS/Draw will allow custom structure queries to be drawn. There is also a Java-based structure search and display applet.

The Locator Codes are hyperlinked at the substance level to biomedical databases at NLM and on the Internet and to the SuperList compilation of chemical substances of interest to Federal and state regulatory agencies. Ease of navigation from the Locator Display Page to these other Web sites and vice versa is a characteristic feature of ChemIDplus.

For advanced searchers, there are three types of structure queries: Substructure Search, Similarity Search, and Exact Structure Search. ChemIDplus facilitates structure searching by providing two options that eliminate the need to draw the structure queries. One option, Use Structure for Query, pastes the retrieved structure from a previous query to the Structure Input Box while the other option, Use Structure for Similarity, starts an immediate search for similar structures.

Further Information

For ChemIDplus content, search strategies, and access, contact:

Specialized Information Services
National Library of Medicine
Two Democracy Plaza, Suite 510
6707 Democracy Boulevard, MSC 5467
Bethesda, MD 20892-5467
Telephone: (301) 496-1131
FAX: (301) 480-3537
e-mail: tehip@teh.nlm.nih.gov
URL: http://sis.nlm.nih.gov

For information on NLM services, contact:

Customer Service
National Library of Medicine
8600 Rockville Pike
Bethesda, MD 20894
Telephone: 1-888-FINDNLM (1-888-346-3656)
e-mail: custserv@nlm.nih.gov

A complete list of NLM Fact Sheets is available at:
(alphabetical list) http://www.nlm.nih.gov/pubs/factsheets/factsheets.html
(subject list): http://www.nlm.nih.gov/pubs/factsheets/factsubj.html

Or write to:

FACT SHEETS
Office of Communications and Public Liaison
National Library of Medicine
8600 Rockville Pike
Bethesda, Maryland 20894

Phone: (301) 496-6308
Fax: (301) 496-4450
email: publicinfo@nlm.nih.gov

Last updated: 28 May 2004
First published: 01 January 1994
Metadata| Permanence level: Permanent: Stable Content