Searching Chemical Structures

Thus, if the user wants to look for literature including requested chemicals or reactions, it is possible to query the database by the first option Chemical Substance or Reaction , The compound can be entered as a query in three different ways drawing the chemical structure in a molecule editor (Chemical Structure) searching by names or identification number, such as the CAS Number (Structure Identifier) and searching by molecular formula (Figure 5-12). 

Feldman A, Hodes, L. An efficient design for chemical structure searching. I. The screens. J Chem Inf Comput Sci 1975 15 147-52. 

Willett P, Winterman V, Bawden, D. Implementation of nearest neighbour searching in an online chemical structure search system. J Chem Inf Comput Sci 1986 26 36-41. 

The information retrieval in MAECIS is accomplished using one of three available commands SHOW, FIND, or SEARCH. The SHOW command is the simplest one to use and requires only a code number or registry number. It allows the user to retrieve all chemical structures and associated information stored under a particular code number. In most cases this fulfills the user s needs. The FIND command is used for complex searches involving various combinations of multiple data fields, handles substructure searching. Queries such structures with a molecular weight between 200 and 250 containing an ester substructure" are handled by the FIND command. Finally, the SEARCH command is used for chemical structure searches. This search takes only seconds and allows the chemist to determine if a particular molecule is already in the database. 

Feldman, Alfred, and Louis Hodes, "An Efficient Design for Chemical Structure Searching I, the Screens," Journal of Chemical Information and Computer Sciences, 15(3), 147-151 (1975). 

Feldman, R. J., "Interactive Graphic Chemical Structure Searching," in Computer Representation and Manipulation of Chemical Information, ed. W. T. Wipke, John Wiley, N.Y., 1974. 

Willett, P., V. Winterman, and D. Bawden, Implementation of Nearest-Neighbor Searching in an Online Chemical Structure Search System. J. Chem. Inf. Comput. Sci., 1986 26, 36-41. 

PubChem Chemical Structure Search South SMUS or Fornmfe [d-CC-CC-Cl Shofcli... 

Databases of Three-Dimensional Chemical Structures, Searching Techniques for... 

The EPO esp cenet (ep.espacenet.com) database contains more than 60 million patents from 85 conntries worldwide (not just European Convention countries). The database is searchable by application number, assignee, inventor, or keywords from the title or abstract. Chemical structure searches are not possible. Patents can be viewed as images of the original document in PDF format one page at a time, or the whole patent can be viewed as a text document. Instantaneous translation from French or German into English is available for the latter document type if required. Equivalent pnblished patents, if any, are also listed and are available in PDF format. The text documents do not show chemical structures or diagrams, but these can be viewed in PDF format if required. 

Free patent information is provided by the website http //www.freepatentsonline.com/, covering U.S., EP, and PCT patents/applications and Japanese patent abstracts. In addition to the usual text-based searches in various search fields, this site also enables graphically input chemical structure searches to be performed on over 9 million compounds (including prophetic compounds) using exact structure, substructure, or chemical similarity searches. Chemistry searches using SMILES strings or chemical names are also possible. Full patent documents may be viewed in text or PDF format. 

Barnard JM. Substructure Searching Methods Old and New. J. Chem. Inf. Comput. Sci. 1993 33 532-538. An overview of the chemical structure search methods used in modem databases and in databases created before the development of computers powerful enough for topological stmcture searching. 

Hodes, L. (1976) Selection of descriptors according to discrimination and redundancy. Application to chemical structure searching. /. Chem. Inf. Comput. Sci., 16, 88-93. 

Some of the special advantages of STN include advanced chemical structure searching, easy searching and cross-searching of complementary data-... 

The PubChem structure search tool enables one to query and subset PubChem Compound by a variety of chemical structure search types and optional filters. The chemical structure search service may be directly accessed using the URL ... 

Step 4. Some of the chemical structures searched for in Step 3 must contain the lead structures of agonists and antagonists for the target protein. Bloassay of the compounds will reveal the structural features necessary for the lead compounds. 

Spectra and chemical structure searches are based on distance and similarity measures as introduced in Section 5.2. Different strategies are known sequential search, search based on inverted lists, and hierarchical search trees. The strategies are explained for search of spectra. 

Watson, D. Some Experiences with the DARC System. In Proceedings of the CNA(UK) Seminar on Chemical Structure Searching of the Published Literature Dareshury, UJC., 17-19 March 1980. Chemical Structure Association, 1982. 

Feldmann, R.J. Interactive Graphic Chemical Structure Searching. In Computer Represent-... 

Gould, S. R. Chemical Structure Searches on an IBM PC from a 5V4 Floppy Disk . Papers presented at the 192nd Meeting of the American Chemical Society, Anaheim, California, 1986, COMP abstract number 14. 

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