Structures Systems Beilstein

The ROSDAL (Representation of Organic Structures Description Arranged Linearly) syntax was developed by S. Welford, J. Barnard, and M.F. Lynch in 1985 for the Beilstein Institute. This line notation was intended to transmit structural information between the user and the Beilstein DIALOG system (Beilstein-Ohlme) during database retrieval queries and structure displays. This exchange of structure information by the ROSDAL ASCII character string is very fast. 

ROSDAL is used in the Beilstein-DIALOG system [17] as a data exchange format. The code can represent not only full structures and substructures but also some generic structures. 

The system has been designed for both an optimised vectorial coprocessing unit connected to a mainframe to free the main CPU from the very special burden of substructure search, and a stand alone microprocessor-based substructure search system for selected parts of the Beilstein structure file (Beilstein Selects). 

The SDF structure file is used for delivery to hosts and in-house customers of the Beilstein structure file. Other delivery formats produced by the registry software include Tel6systemes-DARC and MDL MOLfile formats. Large DARC and MOLfile structure files have been created at the Beilstein Institute for the purpose of benchmarking the DARC-SMS and MDL MACCS-II substructure search systems against the S4 substructure search system developed jointly by the Beilstein Institute and the software house Softron GmbH . 

Vol. 19. General subject index and group index Vol. 20. General formula index Series 1 and II (volumes 1-11) were never published. Volume 12 was issued in two parts, 12A Bicyclic compounds, and 12B Naphthalene, in nine volumes (1948-1955). Volume 13 was published in 1946 and volume 14 in 1940 to which six supplements were added 1951-1962. Supplements 5 and 6 were issued under the auspices of the Beilstein Institute who took over the encyclopaedia in 1954 and combined it with the current supplement to Beilstein. The system of arrangement of Elsevier depends on the structure of the compound and brings together those that are most closely related. Occurrence in nature and in technical products is discussed followed by syntheses from systems with fewer carbon atoms and formation by the degradation of more complicated systems. 

The S4 search system itself embodies several novel and interesting concepts. The search file is built from the Beilstein structure file by encoding every atom of every molecule in terms of its extended connectivity encompassing every atom in the molecule. These compact atom codes are sorted into a file and further compressed. From this large file of atom codes a search tree is generated consisting of the first ten spheres around each atom. This tree forms the index through which the atom code file is accessed. 

Specinfo, from Chemical Concepts, is a factual database information system for spectroscopic data with more than 660000 digital spectra of 150000 associated structures [24], The database covers nuclear magnetic resonance spectra ( H-, C-, N-, O-, F-, P-NMR), infrared spectra (IR), and mass spectra (MS). In addition, experimental conditions (instrument, solvent, temperature), coupling constants, relaxation time, and bibliographic data are included. The data is cross-linked to CAS Registry, Beilstein, and NUMERIGUIDE. 

This reference work differs from Beilstein in that it is baaed upon structural formulae and compounds are grouped according to the carbon skeleton rather than the functional group the latter system has the advantage that closely related compounds are grouped together. The volumes are not published in numerical order but rather on the basis of fields of current interest. They are a valuable supplement to Beilstein. The volumes which have been published to date (1955) are ... 

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. 

Searching journal information continues to be the primary use of SciFinder for the medicinal chemist. One finds it especially useful for searching various topics, for instance, anti-inflammatory treatments. When performing structure/reaction-based searches, many chemists also use Beilstein CrossFire in conjunction with SciFinder. The reaction information from these systems is often complementary, and it is quite useful to have both SciFinder and CrossFire in a medicinal chemistry group. However, companies with restricted budget may have to choose one or the other. 

The structures of five additional endocydic allenes found in the Beilstein database (e.g. an 11-membered ring system [97e]) are probably incorrect. 

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. 

Databases include the Beilstein File, the Gmeliu File, the Registry File, the Description. Acquisition. Retrieval, and Correlation File, and Ihc Structure and Nomenclature Search System. 

Structure searching and display software are host-specific. The Softon Substructure Search System (S4) was developed by the Beilstein Institute and Softon of Graefelfing Germany (50). It is a full structure and substructure searching module. The S4 is used in-house by the Beilstein Institute and is operated by DIALOG. STN uses CAS ONLINE s messenger software for on-line structure searching of the Beilstein on-line database (51). 

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 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. 

ROSDAL. Linear notation scheme devised by the Beilstein Institute. It can contain just connection table information, or it may also contain atom coordinates. Several chemical information systems can convert ROSDAL strings to other structure file formats. 

Fig. A.l. Structure Search for CrossFire Beilstein Beilstein Data Copyright (c) 1988-2006, Beilstein Institut zur Foerdening der Chemischen Wissenschaften licensed to Beilstein GmhH and MDL Information Systems GmbH. All rights reserved.

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