BEILSTEIN RING SEARCH SYSTEM .1. GENERAL DESIGN

One of the most significant advantages of an online database is the possibility of accessing the data in many different ways using different types of search criteria. The Beilstein Online Database (Domokos, L. Mikrochim. Acta 1986, II, 423-429), which is the largest factual data collection of organic chemistry, has more than 400 different search keys. It is available on two online hosts, Dialog and STN. The online experience has shown that the most frequently used access methods are those which select compounds by their structural properties, like full structure and substructure, chemical name, chemical name fragments, molecular formula, molecular weight, atom counts, and Lawson number. The Beilstein ring search system (BRSS) was developed to allow an easy and fast retrieval of compounds by exact or fuzzy definition of their embedded ring systems. This paper gives a general overview of the BRSS itself and of the new database fields supporting the BRSS. An early stage of the development has been reported previously (Domokos, L. In Software Development in Chemistry; Gasteiger, J., Ed.; Springer-Verlag: Berlin, 1990; pp 31-41).