Beilstein data base

The purpose of this paper is to describe the implementation of a structure browsing tool in computerized data bases, with particular reference to the Beilstein data base as an example. The retrieval term which will form the main subject of this paper is the so-called Lawson-Number (LN). For obvious reasons, it is somewhat embarrassing for the present author to give an account of a descriptor which bears his own name. However, the driving force behind the choice of that particular name was not the author himself, but rather a combination of circumstances, the prime being that all sensible names for numbers of all descriptions had already been used up in the early days of the Beilstein Online venture. There were (and still are) the following terms in daily use in the production processes at the Beilstein Institute ... 

The BRN is a number with no structural information whatsoever. It is assigned sequentially to each structure new to the registration software of the Beilstein Data Base. It is the primary key of Beilstein Online. 

Beilstein Abstracts (http //www.chemweb.com/data bases/belabs) is one of the most important databases in organic chemistry due to its completeness (although not for patent data). It is clearly data-oriented. About 300 different physical properties can be searched and retrieved for each compound, if they are reported in the literature. Full access to the database is restricted, but Beilstein Abstracts is available free through ChemWeb (author, title or abstracts are searchable). 

The production of databases has become very expensive and many earlier compendia, such as Beilsteins Handbuch der Organischen Chemie, have been essentially driven out of competition as hardbound volumes (although at this writing much of it remains available through a commercial online data base, Reaxys (www.reaxys. com) owned and operated by Elsevier B.V. in Amsterdam, The Netherlands). Similarly, other specialist databases such as Methoden der Organischen Chemie (Houben-Weyl) have been transformed into Science of Synthesis Houben-Weyl... 

CrossFire Abstracts is a companion to the highly popular in-house database management system Cross-Fir .-/.< jReactions. It provides immediate access to the whole Beilstein knowledge base, with 7 million compounds, 10 million reactions, 20 million factual data, and 50 million hyperlinks, and also to titles and abstracts from the organic chemical literature from 1980 to the present. (See CrossFire Abstracts Titles and Abstracts from the Organic Chemical Literature.)... 

MOLKICK (sold by Springer Verlag), which is described in Chapter 8 of this book, is a memory-resident query editor which converts a structure to a string suitable for uploading to Beilstein/Softron, CAS or DARC data bases. Its chemical structure input is very similar to Beilstein s MOLMOUSE software (55). 

Sandy Lawson s contribution on chemical structure browsing (Chapter 4) may seem peripheral to the main topic of the symposium, but the algorithm he employs could, he hopes, be used for data bases other than Beilstein in future. 

A number of systems now offer graphics-based substructure search capabilities for online access to a variety of chemical structure data bases. From December 1988 the first subset of the Beilstein Online data bank (organic heterocyclic compounds reported in the literature prior to 1960) goes online on STN International. Other hosts, which at present offer only name-based structure and substructure search capabilities are also likely to provide online access to the Beilstein files in the near future these include Dialog, Pergamon Orbit Infoline and Datastar. 

The Beilstein Database. The Beilstein Database, with over 8 million structures, is the oldest in existence, based on the Beilstein Handbook of Organic Chemistry, and contains data that extend back to 1771. The database is produced by the independent Beilstein Institute... 

When the comparison is with the real chemical world, novelty concerns much smaller numbers. In March 2002, the Chemical Abstracts Registry file contained more than 37 million chemical substance registrations, which contained almost 19.5 million organic and inorganic substances. The CrossFire Beilstein database contained data on over 8 million organic compounds on the same search date. It is a tedious exercise, but very much worth the effort, to take databases such as these based on Beilstein and remove trivial small molecules ( non-druglike ) and see how many compounds remain. The result is less than half a million. 

Beilstein database The database covers the scientific literature from 1771 to the present and contains experimentally validated information on millions of chemical reactions and substances from original scientific publications. The electronic database was based on Beilstein s Handbook of Organic Chemistiy. In this database, each compound is given a unique Beilstein Registiy Number which helps in their easy identification. Each substance has up to 350 fields containing chemical and physical data. References to the literature in which the reaction or substance data appears are also given. The content is made available through the CrossFire Beilstein database. 

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. 

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. ... 

While the Beilstein file contains a good deal of data in this area, there are also excellent compilations dedicated to thermodynamic quantities. DETHERM is produced by Dechema, and contains thermophysical properties for ca. 17000 compounds and mixtures (see Chemical Engineering Databases). The subject matter is taken from phase equilibria, PVT behavior, thermodynamic quantities, transport phenomena, surface properties, and electrolyte properties. Attention must also be drawn to the compilations of the US National Institute of Standards and Technology (NIST). The NIST Chemistry WebBook contains thermodynamic data for over 5000 compounds and ion energetics data for over 10000 compounds. The user may search on specific compounds based on name, chemical formula, or CAS Registry Number. Structures are given for all species, as well as common and commercial names. 

---