Chemical Abstracts Conventions

Users of Chemical Abstracts may occasionally have difficulty in locating certain types of compounds. For example, sodium acetate will not be found under C2H3Na02 it appears under C2H4O2, which is the formula of the parent acid (acetic acid). The conventions that Chemical Abstracts uses include the following  

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The index consists of two parts. Part I contains entries referring to the conventional names of compounds as they appear in the preparations of this volume followed by the systematic names in brackets, if the nomenclature differs The bracketed names conform to the systematic nomenclature adopted by the Chemical Abstracts Service starting with Chemical Abstracts Volume 76 (1972) Part II of the index contains entries of the subjects of this volume with compound names in a reversed order of Part I... 

This chapter includes four indices the Alphabetical index, the Chemical Abstract Service (CAS) numbers index, the International Classification of Diseases, 10th Revision (ICD-10) numbers index, and the Organization for the Prohibition of Chemical Weapons key (OPCW) numbers index. OPCW numbers are found in the "Handbook on Chemicals, version 2002," Appendix 2 in Declaration Handbook 2002 for the Convention on the Prohibition of the Development, Production, Stockpiling, and Use of Chemical Weapons and on their Destruction. OPCW numbers were developed to provide an easy method for tracking chemical warfare agents and precursors if CAS numbers were not available. 

Abstract The Chemical Weapons Convention (CWC) is shortly characterised stressing... 

Abstract The chemical weapons convention provides for collection and analisis of... 

Blattner, R., Ferrier, R. J., Fumeaux, R. H., and Ludewig, M., Abstracts, 11th Royal Australian Chemical Institute Convention (2000) and Abstracts, 20th International Carbohydrate Symposium, Hamburg, Germany (2000), B-341, p. 228. 

In this series, three earlier reviews on carbazole alkaloids were published by Kapil (1), Husson (2), and Chakraborty (3) in the Volumes 13,26, and 44, respectively. The present chapter introduces a new classification of carbazole alkaloids and summarizes the recent synthetic efforts. The nomenclature of carbazole alkaloids used in this review is that of Chemical Abstracts. As shown in Scheme 1.1, the conventional tricyclic ring system of carbazole 1 is denoted by A, B, and C, and the numbering starts from ring A. The term carbazole generally refers to a 9H-carbazole. 

When the same number and kinds of substituents are carried by the two aromatic radicals, the IUPAC system simply numbers the substituents in a conventional manner, whereas the Chemical Abstracts system names the compound as an assembly of identical units with the prefix azodi- preceding the name of the unsubstituted parent compound ... 

This chapter presents a concise overview of the present conventions in coordination nomenclature. Generally, the IUPAC rules and recommendations have been followed. For the cases where the IUPAC practices seemed to be out of date or incomplete, the author has drawn upon the vast expertise in nomenclature available at Chemical Abstracts Service. Sections 3.2.3 and 3.4 deal with ligand locant notation and the numbering of polynuclear complexes may be considered provisional. These concepts are still under active consideration in the various national and international nomenclature commissions and committees. The presentation is relatively brief, but it is hoped that the nomenclature principles are evident, especially when examples presented are closely... 

The conventions used in the IUPAC Rules with respect to spelling, position of numerals, italicization, etc., are those of Chemical Abstracts. Current British practice is different in some respects, and it is useful at this point to note two principal differences. British conventions will be used in the present article. 

Alternative rules within the latter system may allow assigning more than one unambiguous name to a compound. The controlled alphabetic listing in the Chemical Substances Index of Chemical Abstracts Service (CAS), a part of the ACS, requires that each compound have a unique name. This convention ensures that all information for a single compound such as H2n—CH2—CH2—OH. which can be unambiguously named 2-aminoethanol. 2-aminoethyl alcohol, 2-hydroxyethylamine, etc., will appear in the index under one name ethanol, 2-amino-. Because universal... 

Corrin and a series of dehydrocorrins are known (Figure 15). Though conventional names are widely used for the dehydrocorrins, some of them are incorrect, and the names cited in Chemical Abstracts are used through this chapter. 

Conventional Terpene Baeyer-Type Recommended For Adoption Ring Index Chemical Abstracts... 

The accepted conventional nomenclature based on the cepham (the fused /3-lactam-perhydrothiazine system) is used throughout this chapter. Carbon atom bonded to C-3 has been numbered as C-10 (or C-3 ). Stereochemistry at C-7 is specified either as absolute configuration R/S, or as a//3 depending on the orientation of the substituent, below or above the plane, respectively. The above abbreviated common names and numbering for the cephalosporins should not be confused with the IUPAC systematic nomenclature as used by Chemical Abstract, which, for example, designates 7-ACA as (6/3,7/3)-3-(acctoxymcthyl)-7-amino-8-oxo-5-thia-l-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid. 

The use of proper chemical nomenclature is essential for effective scientific communication. More than one million new substances are reported each year, each of which must be identified clearly, unambiguously, and completely in the primary literature. Chemical compounds are named according to the rules established by the International Union of Pure and Applied Chemistry (IUPAC), the International Union of Biochemistry and Molecular Biology (IUBMB) [formerly the International Union of Biochemistry (IUB)], the Chemical Abstracts Service (CAS), the Committee on Nomenclature, Terminology, and Symbols of the American Chemical Society, and other authorities as appropriate. For more information on naming chemical compounds, refer to the bibliography in Chapter 18. This chapter gives the editorial conventions and style points for chemical compound names. 

There are disadvantages too. Some databases do not include all of the material available in conventional form for example, much of the early Chemical Abstracts is not available on-line. Another problem is that the software for on-line searching is relatively complex, so it is more difficult to learn and, as a result, on-line searches by inexperienced users can be unreliable. The increasing use of personal computers and graphical input and output have made database searching much easier but a good understanding of the software is stUl essential. Finally the cost of hardware, software, consumables, and the searches themselves, can be considerable. 

As in CHEC(1984) and CHEC-II(1996), oxazole and its derivatives are named and numbered following the conventions of Chemical Abstracts. The general structures are arranged in increasing oxidation state and saturation in Figure 1. 

As in CHEC-I <84CHEC-I(6)177>, the naming and numbering of oxazole and its derivatives follow the convention of Chemical Abstracts. The fully conjugated compounds are called oxazoles (1), benzoxazoles (2), oxazolium salts (3), and oxazole A -oxides (4). Hydroxy-substituted oxazoles exist in the oxo form, and there are five representatives the 2QH)-, 2(SH)-, 4(5//)-, 5(2//)-, and 5(4//)-oxazolones, (5)-(9) respectively. There are two mesoionic structures, the anhydro-4-hydroxy-oxazolium hydroxides (10) and the 5-hydroxy analogues (11), the latter of which are also referred to as the munchnones. Compound (12) is named 4,5-dihydrooxazole instead of A -oxazoline or 2-oxazoline, which is commonly used in the general literature. The other dihydrooxazoles include the less common 2,3- and 2,5-dihydrooxazoles, (13) and (14), respectively. The fully saturated compound... 

The parent isoxazolidine (1) can be named as 1,2-oxazolidine according to the extension of the Hantzsch-Widman system. However, since the corresponding heterocycle (2) with the greatest number of non-cumulative double bonds is conventionally called isoxazole, 1 is most frequently referred to as isoxazolidine, which is used in Chemical Abstracts (CA). The hydro-isoxazole or -isoxazoline nomenclature is used solely in connection with the condensed ring for instance, compound 3 may be called either octahydro-l,2-benzisoxazole (CA nomenclature) or 4,5-tetramethyleneisoxazolidine (as a derivative of the isoxazolidine), or 7-oxa-8-azabicyclol4.3.0]nonane (3 ) (Stelzner method). A bis-isoxazolidine is called tetrahydro-2//-isoxazolo[2,3-6]-isoxazole (4) (CA method), or conventionally isoxazolizidine (4 ). 

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