Beilstein system

There is also a fourth division of Beilstein (systems 4721 -4877) that covers natural products of uncertain structure rubbers, sugars, and so on. These are treated in vols. 30 and 31, which do not go beyond 1935 and which are covered in the collective indexes. These volumes will not be updated. All such compounds are now included in the regular Beilstein volumes. 

This book encompasses indiscriminately all the types of reductions and superimposes them over a matrix of types of compounds to be reduced. The manner of arrangement of the compounds is a somewhat modified Beilstein system and is explained in the introduction. Numerous tables summarize reducing agents and correlate them with the starting compounds and products of the reductions. Reaction conditions and yields of reductions are mentioned briefly in the text and demonstrated in 175 examples of reductions of simple types of compounds and in 50 experimental procedures. 

Fragrance and flavor materials of commercial interest are arranged according to the Beilstein system of functional groups, not according to their sensory properties, since relationships between odor and structure are difficult to establish. However, the Beilstein system has been abandoned in a few cases for practical reasons. 

Within each series of the Handbook the entries are ordered using the Beilstein System of Compound Classification this is a set of rules which enables each organic compound to be assigned a position within the Handbook solely on the basis of its molecular structure conversely, knowledge of the rules enables any compound from the c. 1 million compounds already described in the Handbook to be found rapidly, purely on the basis of its structure. A further advantage of the system is that many structurally related compounds are brought together within the same volume of the Handbook. 

The best way of finding the entry for a particular compound in the Beilstein Handbook is to identify in which volume the compound is listed, and then to consult the appropriate volume index. In order to identify the volume of interest a few basic principles of the Beilstein System need to be understood and these are described below. 

For the purpose of classification in the Beilstein System, all organic compounds are divided into three basic types, viz. acyclic compounds (Volumes 1-4), isocyclic (i.e. carbocyclic) compounds (Volumes 5-16), and heterocyclic compounds (Volumes 17-27). Heterocyclic compounds are further subdivided according to the nature and number of the ring heteroatoms. All heterocycles... 

The position of the entry for any compound is determined by that fragment of its structure which is classified latest in the Beilstein System. Thus, for example, a compound containing a heterocyclic ring, a carbocyclic ring and an aliphatic chain is classified as a heterocycle, irrespective of the other structural elements, since all heterocycles are ordered after acyclic and isocyclic compounds in the Beilstein System. This feature of the systematic classification of compounds is called the Principle of Latest Systematic Entry. 

Derivatives are entered in the Handbook following the entry for the registry compound the order is again determined by the Beilstein System. (If the registry compound was not reported in the literature covered by a particular series, its entry is omitted, but this does not affect the ordering of its derivatives in the Handbook.)... 

Stephen R. Heller, The Beilstein System Strategies for Effective Searching, American Chemical Society, Washington, DC, 1998. 

Rouse, K. and Beckman, R. 1998. Beilstein s CrossFire a milestone in chemical information and interlibrary cooperation in academia, in The Beilstein System System Database and Software, S. Heller (Ed.), Washington, DC American Chemical Society, pp. 133-148. 

Beilstein Database are described in The Beilstein System Strategies for Effective Searching, ed. S. R. Heller (Washington, DC American Chemical Society, 1997). In the 1990s, the Beilstein Institute together with MDL produced an Internet-based client-server system of the Beilstein Database, CrossFire Beilstein, which is now owned and updated by Elsevier Information Systems, Frankfurt. 

CA uses the Hill instead of the Richter or Beilstein system of arranging formulas and of placing the symbols of the elements within these formulas. This practice has the advantage of simplicity and of suitability for inorganic as well as organic compounds. Beils-tein has changed to this practice. 

Consider the structure shown in Figure 2. The operation of the Beilstein System on this structure is unambiguous, as it is with any single complete structure. This structure alone fully localizes the position on the X-axis of the graph of Figure 1, and the printed Handbook indicates this position with a series of five pointers, completely independent of the Series concerned. 

The 12-digit Code. To illustrate this procedure, let us look at the example used above in Fig. 2 the structure is input, and the operation of the Beilstein System on the connection table is then carried out- The structure is recognised as being composed of three fragments (substructures), namely ... 

Beilstein grid, example of entries, 8l-82,84f Beilstein Handbook entry, 8l main series, 8l supplementary series, 8l Beilstein information pool future concept, 89,90f state of progress, 88-89,90f Beilstein system... 

Guidebooks to using Beilstein, which include a description of the Beilstein system, are recommended for anyone who wants to work extensively with Beilstein. Among such sources are ... 

Beim Zusammentieffen mehrerer Isomeren unter ein und derselben Bruttoformel sind die einzelnen Stiehworte entapechend ihrer Konstitation naoh dem Beilstein-System geordnet. 

A new and valuable literature based database and search system, called NetFire, has recently been made available on the Internet by Beilstein Information Systems. It is the first attempt by Beilstein to provide chemical information outside the main area of extracted and evaluated data. The existing Beilstein system, provided via their CrossFire system, is an in-house system which has received wide acceptance since it was introduced in the mid 1990s. NetFire is a very new and different system, a valuable Internet resource. It is yet another example of the innovation of new and modem electronic products by Beilstein. NetFire provides free access to titles, abstracts, and authors from the organic chemical literature, from 1980 to the present. ... 

We may expect a final system to be clearly defined intellectually and organized in a standard nested taxonomy, with some readily understood nomenclature, to provide an overall grasp for organic chemists to see easily the relationships among reaction examples and so to critically evaluate the system in practice. Thus every reaction should have a place in the system, as with structures in the Beilstein system. 

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