Universal structure/substructure

Barnard, J.M. Jochum, C.J. Welford, S.M., A Universal Structure/Substructure Representation for PC-Host Communications . Chemical Structure Information Systems In ACS S3nnposium Series 400, American Chemical Society Washington, 1989 pp. 76-81. 

A Universal Structure/Substructure Representation for PC-Host Communication... 

Varnek, A. Fourches, D. Hoonakker, F. Solov ev, V.P. Substructural fragments A universal language to encode reactions, molecular and supramolecular structures. J. Comp. -Aided Mol. Design 2005, 19 (9-10), 693-703. 

The vernier model also turned out to be an approximation. It is now clear that although the metal atoms in these stmctures are similar to that found in the fluorite parent structure, the anion array is continuously modulated, and expands or contracts throughout the structure to fill the space optimally with respect to the chemical and crystallographic constraints that apply. Although for some modulation wavelengths the anion array is well described in terms of a square net or a hexagonal net, this is not universally correct, and the modulated description is a more accurate representation of the anion substructure. 

Another package in this category, Wisconsin Interactive Molecular Processor (WIMP, written by H. W. Whitlock, University of Wisconsin, Madison, W1 and marketed by Aldrich Chemical Company, Milwaukee, WI [5]) permits structure entry and high-quality output (again without substructure searching or interfacing with other systems). 

Barnard, J.M. Cook, A.P.F. Rohde, B. Storage and Searching of Stereochemistry in Substructure Search Systems . In Chemical Information Systems Beyond the Structure Diagram. Proceedings of a Conference held at the Collie of St Hild and St Bede, University of Durham, UK, 17-20 July 1989 Bawden, D. Mitchell, E., Eds Ellis Horwood Chichester pp. 29-41. 

Grindley, H.M. 3-D Distance Comparisons in Protein Secondary Structure Motifs For Substructure Search Refinement . M.Sc. dissertation. University of Sheffield, 1988. 

Regarding structural databases on the Internet, the WWW chemical structures database established by the Computer Chemistry Center at the University of Erlangen should be mentioned. Currently this database contains more than 2250 chemical structures collected automatically from the Internet, complete with information about the referring html pages. The search operations supported in this database include full structure search, substructure search, formula-oriented searches, and queries on names, CAS-Numbers,... 

The atom connection table has been used for many years, mainly for storage and retrieval of chemical structures and substructures. CAS became the first major user of connection tables when the Chemical Registry System was established. It was then followed by Telesystemes-DARC (Description, Acquisition, Retrieval, and Correlation) devised at the University of Paris. In comparison with the CAS format, that used in DARC was definitely more compact and easier to process on minicomputers. 

MarinLit As its name clearly implies, this is a database on the literature concerning natural substances of marine origin. The database is equipped with a graphic interface allowing the user to search by structures and substructures and, since version 11.4 (February 2002), it is possible to obtain a simulation of the proton and carbon-13 NMR spedra. Created and maintained by M.H.G. Munro and J. Blunt at the University of Canterbury at Christchurch (New Zealand), the database is updated twice a year, In version 12.3 (February 2004), the database has 15 485 references and approximately 15000 importable... 

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