To learn more about a substance in CAS REGISTRYSM that does not have any literature or patent references in an STN® database, consult the following fields:
- Source of Registrations (SR)
For CAS Registry Numbers® 97314-93-7 and higher, the SR field indicates the reason for first registering the substance. You can EXPAND or SEARCH the content of the SR field.
- Class Identifier (CI)
For substances registered to support CAS registration policies, the CI field may provide additional insights as to why the substance was registered.
Examples of substances in REGISTRY without any literature or patent references in an STN database.
The substance was initially registered |
And the SR (and CI) field contains |
Then the substance is |
To find additional information |
To support CAS registration policies |
SR: CA CI: RPS |
A component of a multicomponent substance such as a copolymer, salt, or mixture A translated protein from GenBank |
Search the CAS Registry Number in the Component Registry Number (/CRN) field to retrieve the multicomponent substances containing this component. Many of these multicomponent substances will have references. |
From chemical libraries in CAS Chemical Supplier Insights |
SR: Chemical Library |
An individual member of a chemical library |
Most of these substances are either new registrations not yet linked to CAS Chemical Supplier Insights or substances that were removed from CAS Chemical Supplier Insights at the suppliers request. See the name of the supplier in the SR field. |
From chemical catalogs in CAS Chemical Supplier Insights |
SR: Chemical Catalog |
From a chemical catalog |
Most of these substances are either new registrations not yet linked to CAS Chemical Supplier Insights or substances that were removed from CAS Chemical Supplier Insights at the suppliers request. See the name of the supplier in the SR field. |
From web sources |
SR: Other Sources |
From a web source |
Contact the database supplier listed under SR. |
From a reaction database |
SR: Reaction Database |
From processing of a reaction database |
Check the LC field. |
From data collections that are not represented in STN databases |
SR: American Society of Hospital Pharmacists SR: Environment Canada SR: European Union SR: U.S. Adopted Names Council (USAN) SR: U.S. Environmental Protection Agency (US EPA) SR: U.S. National Library of Medicine (NLM) SR: World Health Organization (WHO) |
Included at the request of one of these agencies |
Consult the original source for any additional known information. |
By CAS Custom ServicesSM |
SR: CAS Custom Services |
Included as a request submitted to CAS Custom Services |
Additional information is not available. |
*The CA Index Guide and Ring Systems Handbook have been discontinued.
Substances that become referenced due to REGISTRY updates
The content of the SR field reflects the reason a substance was initially registered. However, because REGISTRY is updated daily, reference information may be added for a substance that was initially registered without a reference. Here are two examples of substances initially registered from other sources. The first example does not have any associated references, while the second example is associated with a CASM/CAS References reference.
References not available:
References available: