Registry Handbook - Number Section

The Registry Handbook - Number Section contains all the CAS Registry Numbers so far assigned. It is, therefore, a part of the CAS Registry database, which was described in Sect. 1.3.1. 

Consecutive Registry Numbers are awarded to each new substance registered in the CAS Registry database. Although they contain no inherent information about the chemical composition or structure of the substance, they represent a unique identification tag for each substance and its stereo chemical descriptor. E.g. different CAS Registry Numbers are assigned to isomers, chemicals marked with isotopes or ions with different valences. It is important to know that unspecific chemicals also have a unique number  

In order to find all literature concerning o-xylene for online searching, 95-47-6 has to be used as well as 1330-20-7. Under the number for the unspecific substance information on o-xylene can also be included. 

Exactly defined oligomers are indexed individually and receive a unique CAS Registry Number. Starting in 1987 block, grafted and altering copolymers are separately stored in the CAS Registry database. 

N The digits of the CAS Registry Number from right to left, excluding the check number R Check number Example 7732-18-5 

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For the organic chemist, knowledge of, and access to, the more familiar components of the printed products of Chemical Abstracts is still desirable CA abstracts CA Volume Indexes and CA Collective Indexes CA Index Gnide CAS Source Index (CASSI) Registry Handbook Number Section the Ring Systems Handbook and CA Selects. 

Eollowing the introduction of the system of CAS registry numbers in 1965 (see Chapter 9), CAS published the Registry Handbook—Number Section. The initial handbook covered the period 1965-1971 (registry numbers 35-66-5 to 33913-68-7). Annual supplements of registry numbers were published from 1972 to 2001 (registry numbers 33913-69-8 to 380148-63-0), when publication... 

The CAS Registry Handbook (Number Section) and supplements should be consulted for obtaining the substance name and elemental formula corresponding to a Registry Number. 

The Registry Handbook—Number Section provides the CA Index names and the molecular formulas for more than 15 million substances. The base book covers 1965—1971. Additions are provided in annual supplements. 

Present name attributed by CAS Registry Handbook Number Section-1995... 

The Registry Handbook - Number Section, also available in microform, lists CA index names and molecular formulas of all the chemical substances recorded in the CAS Registry. The Registry Handbook - Common Names, in microform, links common names with CA index names for some selected 1.5 million substances. 

Fig. 71. Excerpt from the Registry Handbook - Number Section...

The handbook has some useful appendices that include the CAS registry numbers, a biological activity index, a formula index, and a name index that also includes synonyms. When looking up a compound in one of the indexes, you need to remember that the numbers provided are compound numbers, rather than page numbers. There is also a very useful section on organic name reactions that includes references to the primary literature. 

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