Chemical Abstracts Service examples

Chemical Abstracts Service. The Chemical Abstracts Service (CAS), a division of the American Chemical Society, has produced Chemical Abstracts (CA) since 1907. Since the demise of Chemisches Zentralblatt and British Chemical Abstracts CA has been the preeminent medium for documenting new pubhcations in the field of chemistry and chemical engineering. CA documents chemical pubHcations of all types. It is not a patent database per se, but its patent component is larger than most databases devoted entirely to patents. Thus, for example, the number of patent references in CA for the years 1991—1993 ranged from 95,500—99,400 per year. 

The Chemical Abstracts Services Registry Number and lUPAC nomenclature for PVP are [9003-39-8] and l-ethenyl-2-pyrrohdinone homopolymer, respectively however, it is known by a variety of approved names by foreign and domestic regulatory authorities. For example ... 

Chemical Abstract Service Registry Number for a typical example of the sensitizer listed. See Figure 7 for some stmctural formulas. 

CAS Number - Chemical Abstracts Service Registry Number A CAS (Chemical Abstracts Service) Registry Number is a unique identifier that tells you, for example, that aeetone and dimethyl ketone are actually the same substance. The Chemical Abstracts Service is a division of the American Chemical Society. OSHA only requires certain items on an MSDS and a CAS number is not one of them. However, authors of MSDS s are allowed to add additional information, such as the CAS number, if they desire. The numbers you see on trucks on the highway are not CAS Numbers, butU.S. Department of Transportation (DOT) codes, which are not necessarily specific to each chemical. Their aim is to assist emergency responders. 

Finally, journal web sites and fee-based services can be used with success to find additional references to key topics. Examples of services that are particularly good include the American Chemical Society s Chemical Abstracts Service (CAS http //www.cas.org/) and their journal search page (http //pubs.acs.org/index.html) the Elsevier Scopus search engine (http //info. scopus.com/) and ScienceDirect database (http //www.sciencedirect.com/) and the ISI Web of Knowledge (http //isiwebofknowledge.com/). 

It becomes difficult to decide whether, for example 1 is cis or trans isomer No. two groups are the same and the same is true for the compound II. The Chemical Abstracts Service has proposed an unambiguous system that has been adopted by IUPAC and is based on the preferences of groups. It is also called the E-Z system and applies to alkene diastereomers of all types. 

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... 

As a compound is represented by a square matrix having a number of rows and columns equal to its number of atoms, it is clear that such a representation cannot be used for input purposes, but is rather an internal representation of structures and reactions. Furthermore, as the numbering of the atoms in a chemical compound is a priori arbitrary, several connectivity tables can be deduced from a given compound. Thus, special algorithms are required to obtain a canonical connectivity table. For example, the Chemical Abstracts Services have recourse to an algorithm devised by Morgan [234]. 

For reasons of economy of space, some volumes usually treated in this serial publication as books are styled as periodicals [as recommended by CASSI (Chemical Abstracts Service Source Index of the American Chemical Society)]. For example, Chem. Heterocycl. Compd. refers to the Weissberger-Taylor series The Chemistry of Heterocyclic Compounds published by Wiley (Interscience) Alkaloids (London) is the Specialist Periodical Report, covering that subject, of the Chemical Society (London). 

Literature searching—for example Chemical Abstracts Service http //www.cas.org Litlink literature server http //www.litlink.com Science Citation Index http //www.isinet.com Scirus http //www.scirus.com Thomson/ISI Web of Science http //www.isinet.com/isi/ products/citation/wos/. 

Finally, there are extensive classes of heterocycles, which are intramolecularly coordinated 3-boraheteropropanes or 3-boraheteropropenes. For example, compound 25 would be 1,2-phosphoniaboratolane. Chemical Abstracts Service (CAS), which uses the kappa system to name (T-coordination compounds, indexes 25 as dihydro[3-(phos-phino-KP)propyl-KC]boron. Heterocyclic chemists may find the CAS system cumbersome. It will not be used in this chapter. 

Recent reviews for hyphenated techniques have also been published,14 15 and the field continues to grow rapidly. As of writing the present chapter, Chemical Abstract Services lists over 2600 entries for LC-NMR alone The possibility of presenting an authoritative work on the whole topic of hyphenated characterization techniques in a single chapter would be, therefore, impossible. Instead, a few techniques have been chosen, based on the author s experience, to be common and useful. The vast majority of these examples are organic qualitative analyses at trace levels to address the commonly asked question in the pharmaceutical industry What is it . 

An example of the process is the estimation of the toxicity to D. magna of the simple organic isopropylamine. The compound was given a unique identification and that is usually the Chemical Abstracts Service (CAS) number for easy identification. The chemical structure is then represented in SMILES and the model selected. In the case of the D. magna model the estimate was ... 

One or more national standardization organizations and the International Organization of Standardization approve standard names. The chemical names are either according to the rules of the International Union of Pure and Applied Chemistry or according to Chemical Abstracts. The so-called Chemical Abstracts Services Registry Number (CAS-RN) is a number that makes it easy to find the product or chemical in databases from Chemical Abstracts. The standard names are regarded as ordinary nouns, but the pesticide products are sold under a trade name that is treated as a proper name with a capital initial letter. We use the various names of a fungicide as an example ... 

Figure 6 Example types of 3D fragments investigated at Chemical Abstracts Service.

The hazards of chemicals and commodities can be ranked by various systems of commodity classifications. Chemical identity can be established through the International Union of Pure and Applied Chemistry (IUPAC) name, trade name, common name, United Nations/North America (UN/ NA) number, Chemical Abstract Service (CAS) registry number, Registry of Toxic Effects of Chemical Substances (RTECS) number or chemical formula. As an example, acrylonitrile can be identified as follows ... 

A few other entry-level jobs entail no laboratory work. They track an orbit remote from the pharmaceutical industry nucleus, but make indispensable contributions to this and other chemical industries and to the community of researchers. For example, the Chemical Abstracts Service employs organic chemists to summarize the world s scientific literature. Academic qualifications span the range from bachelor s to doctor s degrees strong candidates know languages like Japanese, Russian, or German. 

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