Searching Print Chemical Abstracts

Brief Summary:

Finding abstracts and references to articles:

1. To find the most recent information, use the keyword indexes in the Weekly CA issues.

2. Going back in time, use the Subject Indexes in the Semiannual Volumes published since the last collective index. FIRST, look up the appropriate index term in the Index Guide for that time period.

3. Going still further back in time, use the Subject Indexes in the Collective Indexes. FIRST, look up the appropriate index term in the Index Guide for that time period.

4. Copy down the volume and abstract numbers. Find the abstracts and bibliographic information in the Semiannual/Annual Volumes.

I. Chemical Abstracts Collection:

CAS is the producer of the world's largest and most comprehensive databases of chemical information. Chemical Abstracts include approximately 16 million documents and the Registry file has more than 28 million substance records.

The Chemical Abstracts Collection consists of the following elements:

  • Weekly Issues: contain the abstracts, bibliographic information, and three indexes
  • Index Guides: refer to the accepted terms used for indexing for a particular time period. Use these terms to search the Subject Indexes
  • Indexes:
    • Weekly Issue Indexes
      • Issue Keyword Index: terms from article abstracts and titles
      • Issue Author Index
      • Issue Patent Index

    • Annual/Semiannual Volume Indexes
      • General Subject Index: reactions, processes, equipment, substance classes, plant & animal species
      • Chemical Substance Name Index: provides a systematic CA index name for common and trade names of chemical substances
      • Author/Inventor Name Index
      • Patent Number Index
      • Molecular Formula Index
      • Index of Ring Systems

    • Date when each index was introduced:
      • 1907 Author Index
      • 1907 Subject Index (Split in 1972 into General Subject Index and Chemical Substance Index)
      • 1916 Index of Ring Systems
      • 1920 Formula Index
      • 1935 Numerical Patent Index
      • 1963 Patent Concordance
      • 1968 Index Guide
      • 1981 The Numerical Patent Index & Patent Concordance was consolidated into Patent Index

    • Collective Indexes
      • Same as annual volumes; Volume Indexes are merged; Saves searching time and shelf space:

          Every 10 years:
        • 1st Collective 1907-16 v. 1-10
        • 2nd Collective 1917-26 v. 11-20
        • 3rd Collective 1927-36 v. 21-30
        • 4th Collective 1937-46 v. 31-40
        • 5th Collective 1947-56 v. 41-50
          Every 5 years (annual volumes):
        • 6th Collective 1957-61 v. 51-55
        • 7th Collective 1962-66 v. 56-65
        • 8th Collective 1967-71 v. 66-75
        • 9th Collective 1972-76 v. 76-85
          Every 5 years (semiannual volumes):
        • 10th Collective 1977-81 v. 86-95
        • 11th Collective 1982-86 v. 96-105
        • 12th Collective 1987-91 v. 106-115
        • 13th Collective 1992-96 v. 116-125

    II. Finding Articles:

    Each abstract in CA has a variety of access points. As with any information search, you start with what you already know. This will help determine your access point. You can use any of the following to begin your search: areas of interest, general subject terms, chemical substance names, molecular formulas, ring systems, names of authors, coauthors, or inventors, or patent numbers.

    • Area of Interest:

      Use this access point of you have only a vary vague notion of your interest. The weekly abstracts in the Chemical Abstracts system are placed into one of 80 sections based on the principal interest of the document. The 80 sections are arranged in five broad groups: Biochemistry, Organic Chemistry, Macromolecular Chemistry, Applied Chemistry & Chemical Engineering, and Physical, Inorganic, & Analytical Chemistry. Cross-references are provided at the end of each section.

    • General Subject Indexes:

      Use these access points if your information needs are more focused.
      • Each weekly collection of abstracts has an index of keyword phrases which are chosen from the abstract text and document titles. The Keyword Index is only available for the weekly issues since use of keywords would make the yearly volumes and collective indexes too massive. If you are looking for information about cancer-causing materials, you might use keywords such as cancer, carcinogen, tumor, or malignancy.

      • 1. For the Semiannual Volume Indexes and the Collective Indexes, first go to the Index Guide for that particular time period. (The Index Guide began in 1968; prior to 1968 cross-references were included in the Subject Indexes.) The Index Guide will refer you to the correct Subject Term for a particular time period. For all the cancer-causing terms used in the Weekly Keyword Index, you would be referred to the single term "Carcinogens". You can also get CAS Registry Numbers from the Index Guide.

      • 2. Using the correct term found in the Index Guide, go to the General Subject Index in the semiyearly volumes or the Collective Index to find the Abstract Number of articles on that subject. The abstract number consists of one to six digits followed by an alphabetic character. The small number is just for CA quality control, but you can use it to confirm that you have found the correct abstract. People are often confused, because there two volumes of CA for each year from 1977 onward. The capital letters stand for: B=book, P=patent, and R=review article.

      • 3. Look up the Abstract in the abstract volumes. The entry will also include the bibliographic information for the article or document.

      • 4. Copy the bibliographic information for the article or document. Check to see if we have the journal. If, not, order through Interlibrary Loan


    • Chemical Substance Index:

      • Many substances have several names; some have hundreds of names. CA Index Names are based on principles adopted by the International Union of Pure and Applied Chemistry (IUPAC). The principles ensure that each substance receives a single name which completely describes a single substance. The rules for deriving CA index names can be found in Appendix IV of the Index Guide.

      • Substances are arranged alphabetically in the Substance Index by Parent, Substituents, Modification, then Stereo. For example:

Cyclohexanecarboxylic acid, 4-chloro-3-[2-(methylamino)ethyl]-, methyl ester, (1 alpha, 3 beta, 4 beta)-
PARENT SUBSTITUENTS MODIFICATION STEREO

      • 1. Use the appropriate Index Guide to find the systematic CA index name for common or trade names of chemical substances.

      • 2. Use the correct name from the Index Guide to search the Semiannual Volume or Collective indexes, using the Chemical Substance Index. Note the abstract numbers of interest.

      • 3. Look up the Abstract in the abstract volumes.

    • Molecular Formula Index:

      • If you have the molecular formula for a substance, you can use the Molecular Formula Index. This index provides CA index names, CAS Registry Numbers, and abstract numbers for substances.

      • In the Formula Index, elements are arranged by the Hill System. For all compounds containing carbon, C is listed first, followed by H, if present, and them by remaining elements in alphabetical order. The resulting Hill formulas are arranged in ascending numerical order. For example, C is listed before C2. CH appears before CH2. Formulas for substances that do not contain carbon are arranged alphabetically by element symbol, therefore some formulas will differ from the usual chemical conventions.

      • If a large number of references are published for a particular entry, abstracts will not be listed. You will need to note the index names, and used the Chemical Substance Index to find abstracts.

    • Ring System Index:

      For example the ring analysis for the ring parent in Carbapenem (1-Azabicyclo[3.2.0]hept-2-ene-2-carboxylic acid, 7-oxo-) would be:
      Number of rings: 2
      Size of rings: 4, 5
      Elemental analysis: C3N-C4N

      • 1. Go to 2-Ring Systems
      • 2. Under 4,5 look for C3N-C4N
      • 3. You will find 1-Azabicyclo[3.2.0]heptane, the index name.
      • 4. Use the Index Name in the Chemical Substance Index to find references about substances that contain that ring system.
      • You can also consult the Ring Systems Handbook

    • Author Index:

      • The Issue and Volume Author Indexes list authors, coauthors, inventors, patent assignees, and corporate authors, and link them with abstract numbers.
      • In the Issue Indexes, only the last name and initials are included. The Volume Indexes list the full name. Note that for identical last names, the order is alphabetical by first initial and second initial rather than by letters of the first name. This can be confusing.

    • Patent Number Index:

      • Beginning in 1981, references related to patent numbers can be found in the Patent Number Indexes.
      • For information related to Patents prior to 1981, use the Numerical Patent Index and the Patent Concordance

    • Finding the Abstract:

      • Use the abstract number to find the abstract and bibliographic information.
      • Use the bibliographic information to find or order the relevant articles.

      Example:

      116: 214261y Synthesis and biological evaluation of functionalized epoxides structurally related to the carbapenem family. Marchand-Brynaert, Jacqueline; Davies, John; Ghosez, Leon (Lab. Chim. Org. Synth., Univ. Cathol. Louvain, BG-1348 Louvain-la-Neuve, Belg.). Heterocycles 1992, 33(1), 313-26 (Eng). Epoxides syn- and anti-I, topol. related to the carbapenem antibiotics, were designed as potential alkylating inhibitors of the bacterial.....

      CA Volume: 116
      CA Abstract Number: 214261
      Check Number: y
      Article Title: Synthesis and biological evaluation of functionalized epoxides structurally related to the carbapenem family.
      Authors: Marchand-Brynaert, Jacqueline; Davies, John; Ghosez, Leon
      Location of Work: (Lab. Chim. Org. Synth., Univ. Cathol. Louvain, BG-1348 Louvain-la-Neuve, Belg.).
      Journal Title: Heterocycles
      Publication Year: 1992
      Volume, (Issue) 33(1)
      Pages: 313-326
      Language: (Eng)
      Abstract: Epoxides syn- and anti-I, topol. related to the carbapenem antibiotics, were designed as potential alkylating inhibitors of the bacterial.....

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