Formula indexes Chemical Abstracts

The entries in Tables XIV-XXII have been arranged in order of formula, first the carbonyl compound then the olefin, as they would be found in Chemical Abstracts Formula Index. 

This same inquiry brought forth the information that 71.9% of our abstractors use the Chemical Abstracts Formula Indexes, though they find the Subject Indexes primarily more useful by the wide margin shown in the table. Another more extensive inquiry has shown that 48.6% of our readers use the Subject Index regularly while 33% use it occasionally. The corresponding figures for the Author Indexes are 19.9 and 40.0%, respectively. 

CAS Registry Number Index Author Index General Subject Index Patent Index Formula Index Compound Index Chemical Abstract Number Index Organisation Journal Title Index Language Index Year of Publication Index Document Type Index... 

From the dawn of organic chemistry as such to the present time there exists a continuous record in fonnula index form (Table II) of the compounds of this large branch of chemistry. Inorganic chemistry is not so fortunate. [Hoffman (12) indexed organic compounds by formula to 1909.] From this date to 1920, when Chemical Abstracts began indexing by formula, there is no compilation of inorganic compounds by formula. 

Chemical Abstracts—Subject Index and Formula Index (annual). Chemical Abstracts Service, American Chemical Society, Columbus, Ohio. 

If thorough searches in both Beilstein and SciFinder turn up no exact matches for the structure in question, it is advisable to search the molecular formula and/or name in the pre-1967 Chemical Abstracts printed indexes. If you still are unable to find a match, you can fairly safely assume that the compound has not been fully characterized in the literature. Further searches for similar compounds can then begin. 

The Chemical Abstracts System (CAS) produces a set of various databases ranging from bibliographic to chemical structure and reaction databases. All the databases originate from the printed media of Chemical Abstracts, which was first published in 1907 and is divided into different topics. Author index, general index, chemical structure index, formula index, and index guide arc entries to the corresponding database (Table 5-3). 

If you have access to Chemical Abstracts, look up each alcohol in the Formula Index and see if it has been prepared, or if it is only a theoretical curiosity. 

The systematic nomenclature used originally the term imidazo-1,2,3-triazine. The Chemical Abstracts indexes use the more accurate name imidazo[4,5-d]-Z -triazine (141). The numbering of the substituents is different in the two systems of nomenclature as may be seen in the formulas. 

According to the systematic nomenclature these substances were first named l-f-triazolo[d] pyrimidines in compliance with the general principles of the Ring Index/ More recent papers and Chemical Abstracts indexes use the term i -triazolo[4,5-d]pyrimidine (147) in accord with the lUPAC nomenclature. The numbering of substituents when using the last-mentioned name is different from that of the 8-aza analogs. For the formulas of oxygen and sulfur derivatives names derived from the lactim or thiolactim form are almost exclusively in use (in common with the purine derivatives). These derivatives are thus described as hydroxy and mercapto derivatives, respectively. The name 1,2,3,4,6-pentaazaindene is used only rarely for this system. 

In Chemical Abstracts and in Beilstein specific azo compounds are found under the heading diazenes . As their systematic nomenclature may be very complex (polyazo dyes ), it is much easier to search for them with the aid of the Formula Index of Chemical Abstracts. 

Carboranes are also called o-carboranes, while the 1,7- and 1,12-isomers are m- and / -car-boranes respectively. Chemical Abstracts uses the sequence C-H-B-N (etc.) in the Formula Index, whereas inorganic textbooks prefer B - C - H - N. 

Further steps toward universality are taken by the replacement of element and compound names wherever possible by symbols and formulas, and by adding to data in older units their recalculated SI equivalents. The usefulness of the reference sections has been increased by giving journal-title abbreviations according to the Chemical Abstracts Service Source Index, by listing in each reference all of its authors and by accompanying references to patents and journals that may be difficult to access by their Chemical... 

Compounds are identified by an IUPAC approved name [93-ano-l], the empirical molecular formula, and the Chemical Abstracts Service Registry Number. A summary table is available for each compound which includes the reported temperature and density values, an assigned uncertainty for the density, the difference between the observed and smoothed density values and an index key to the source of the data. A complete list of references, identified by the index keys, appears at the end of the volume. 

A single unstable compound of known composition is placed in the main first volume and is located on the basis of its empirical molecular formula expressed in the Hill system used by Chemical Abstracts (C and H if present, then all other element symbols alphabetically). The use of this indexing basis permits a compound to be located if its structure can be drawn, irrespective of whether a valid name is known for it. A representation of the structure of each compound is given on the third bold title line while the name of the compound appears as the first bold title line. References to the information source are given, followed by a statement of the observed hazard, with any relevant explanation. Cross-reference to similar compounds, often in a group entry, completes the entry. See Trifluoroacetyl nitrite p. 244. 

One common azeotrope is ethyl alcohol 96% water 4%. This combination can be boiled to dryness at one constant temperature. I cannot go into all the azeotropes you may run into during drug manufacture. So, before you attempt any formula, you must go to a science library and research all of the chemicals, solvents, reagents, etc., that are used in that particular formula and learn what can and cannot be used with what. Look in Chemical Abstracts, the Merck Index, or one of the many other fine reference books available. 

There are millions of different precursors for thousands of different dmgs, making it impossible for me to list all of them. I will stick with the more commonly called for items. If you need to find something that I have not listed, look in the Merck Index or Chemical Abstracts to find a reference of where the synthesis of this precursor can be found. At the end of the formulas given here, I have listed some hints or ways to get good precursors out of over the counter medication, like cough syrup, asthma pills, motion sickness pills, etc. Some of these precursors are psychoactive as is, such as ephidrine. 

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