CrossFire data structure

Crossfire Beilstein Information Service Three main types of data, structural and properties, reactions including preparations and chemical literature references. 

Factual databases are generally described in terms of the standardization of the data structure and the data content. In the case of the Beilstein file and CrossFire the following distinction is important to note, and will apply also to other major sources of factual data (e.g., Gmelin). 

The top level of architecture (Table 4) of this very large data collection is fundamentally different in its data structure from the Beilstein Handbook, or the Beilstein file at STN or DIALOG, which have never claimed to be reaction- or document-oriented, and are simple linear lists. It is ultimately responsible for the unifying hyperlink philosophy in CrossFire, which contains upwards of 50 million hyperlinks (see below). 

The CrossFire Beilstein database is the world s largest compilation of chemical facts. This database indexes three primary data domains substances, reactions and literature. The substance domain stores structural information with aU associated facts and literature references, including chemical, physical and bioactivity data. The reaction domain details the preparation of substances, enabling scientists to investigate specific reaction pathways with reaction search queries. The literature domain includes citations, titles and abstracts, which are hyperhnked to the substance and reaction domain entries. It contains over 320 million experimental data, over 10 million reactions and data indexed from over 175 journals. 

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.

The literature search of X-ray crystal diffraction data was conducted by means of the Cambridge Structural Dalahase (1997) and Beilstein Crossfire... 

Crossfire is usually searched by drawing a chemical structure or reaction. It is also searchable by identifying elements, such as chemical name, name fragment, CAS RN, and molecular formula, as well as by numeric and keyword searches in various data fields. Crossfire, which will be fully replaced by a... 

Beilstein provides a large amount of chemical and physical data, as well as many retrospective references to preparation and reaction articles. Searching in Crossfire is compound-based it allows searching by chemical name, name segment(s), molecular formula. Registry Number, and (sub)structure. 

This description sees the elements of the database as structures linked to properties linked to references, and a chemical reactions database is included . This reflects exactly the historical development of the Beilstein Handbook, and later the Beilstein file on STN and DIALOG these collections are lists of compounds, with subsections on property type, linked to sub-subsections of reference lists. But the CrossFire implementation is much more than this. It has a different data orientation, and can justly be regarded as a new implementation, in fact a... 

The situation is not nearly as favorable for exporting results. Accord by Synopsys, the new Beilstein CrossFire for Excel clients, and particularly ISIS, are much more flexible than others, enabling the user to extract almost any desired structure or data into a spreadsheet of her or his definition for postprocessing of results. One step further, condensing a number of similar structures into a common structure plus R groups, is already realized in ISIS structure-activity relationship (SAR) tables and Accord. Such a feature would be particularly useful for the large databases as they are the most in need of such tools, but they lack them at present. Apart from the standard display of reactions, the public database CASREACT (and STN Cheminform RX) permit only role-specific extraction with STN s powerful SmartSelect of compounds from reactions to collect, for example, reagents or solvents from a set of reactions. 

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