Compound Name Searching

Table 10. Output excerpt from a compound name search in the Cambridge Crystallographic Database showing independent occurrences of the search string solvent as a result of logical operations cross-referenced with different possible combinations of other denominations. (The final figure seems to be a pessimistic estimate)...

A special feature is provided for searches of compound names and their synonyms. These fields may be searched separately (as COMP or SYNO) or together under the composite field name XNAM. Here, the two names are first stripped of their non-alphabetic characters (blanks, numbers, punctuation symbols) and then concatenated. This feature removes some, but not all, of the possible vagaries of compound name searching and is discussed further in Section 3.7.3. 

Table 10. Output excsipt from a compound name search in the Cambridge Crystallographic Database showing independent occurrences of...

A search for derivatives of L-glutamate can be performed by a substructure search (SSS) (sec Section 6.3). figure 10,3-24b shows the query of the SSS observe that here, too, the stereochemistry can be specified and this is then considered in the SSS. The query provides 25 hits, including L-glutamatc, N-acctylghjtamate, etc. but also compounds such as tctrahydrofolatc, folate, etc. which would never be found by a name search,... 

To seat ch for available starting materials, similarity searches, substructure searches, and some classical retrieval methods such as full structure searches, name searches, empirical formula searches, etc., have been integrated into the system. All searches can be applied to a number of catalogs of available fine chemicals (c.g, Fluka 154]. In addition, compound libraries such as in-housc catalogs can easily be integrated. 

In the search for new fluorometric reagents for trace metal determinations, ferroin-type compounds, namely 2-(2-pyridyl)-2//- and 2-(3-isoquinolyl)-3//-imidazo[4,5-/i]quinolines, and their silver, lead, and zinc chelates were tested for luminiscence in aqueous ethanol solutions at various pH values (80TAL1021). 

The CD-ROM version of the data base can be efficiently searched with a menu-driven type of software called Search Express. It allows one to search with Boolean expressions as well as individual words and/or frequency of hits as a function of the number of documents retrieved on a given topic. Numerous searchable fields have been included, allowing one to retrieve information by a variety of means, for example, the compound name the chemical registry number, the amount of material released into the air, water, or land the location of the site of release and the SIC code of the releasing party. One can also employ ranging methods with available numeric fields and sorting of output. 

Each series has a set of keywords that specify the series properties. The database can be searched by author name, citation, compound name, SMILES or keywords. A search of a substructure or a generic pattern is also possible. The pattern of molecules in a series is highlighted. Compounds in most series include the same or parent structures with different functional groups. Many series also include existing drugs or other lead compounds. A possible correlation can be derived between the structure and the measured bioactivity. 

To obtain useful information on chemical (including biochemical) compounds from ChemFinder at http //www.chemfinder.com, enter the compound name and click Search. The server returns with synonymous names, chemical formula and structure, and onsite information, as well as links for further biochemical information. The structure can be saved in. cdx format (ChemDraw) and viewed with Chem3D. 

There are 19 text fields available for searching, e.g. compound name, synonym name, authors names, journal volume and page numbers , etc. The general test construct... 

The book s contents and the two indexes (species classes and compound names) may provide a method for quicker searching. 

In the course of a search for antitumor compounds in dinoflagellates, the culture broths of two strains of Pr cf reticulatum showed extremely potent cytotoxicity against human tumor cell lines. The four equally active compounds, named protoceratins III, III, and TV, were purified and their structures were studied. The major compound (protoceratin I) was proved to be identical to homoYTX... 

Spectral data banks contain all sorts of information about a particular substance in the form of tables. The requested field of a table can be accessed by the user either via abbreviations (e.g., MF for molecular formula) or via input masks, which place the necessary denominations of the field at the user s disposal. Some fields may contain searchable information only as alphanumerical text (e.g., compound names), others may be searched only numerically (e.g., molecular weight). In the case of numerical fields, some numerical operators (e.g., < = > or-for area allocation) may also be applied. 

One of the most useful features of the NIST WebBook we have found is the name search, where a large selection of alternative names for a particular compound are available and searchable, greatly increasing the chance of finding the information you want on a particular substance of you do not know the lUPAC or CAS name or the CAS registry number and are not reaUy too sure of the chemical structure. However it is possible to upload chemical structures for example (Fig. 24.5). 

Anderson and Covert (1967) have described a computer search system for the retrieval of infrared data. The system uses an IBM 7080 computer to search the data on magnetic tape for about 100,000 compounds, 90,000 of which are from the ASTM collection. Eastman Organic Chemicals, Rochester, New York 14650, runs a service based on this system. One can send copies of the infrared curve or curves of unknown compounds and ask for service under the catalogue number Eastman No. 6070. The computer output is a printed report listing in order of best probable match the names of up to 25 compounds most closely resembling the unknown compound. This search service supplies names of compounds only, not infrared spectra. 

PubChem A chemical database is a database specifically designed to store chemical informatioa Chemical stmctures are traditionally represented using hnes indicating chemical bonds between atoms and drawn on paper (2D stmctural formulae). Various chemical databases are available on the Internet which are free for all. Large chemical databases are expected to handle the storage and searching of information on millions of molecules. PubChem is one of the free chemical databases which is developed by the National Center for Biotechnology Information (NCBI). More than 24 millions of compound stmctures and descriptive datasets can be freely downloaded from PubChem. PubChem is a user-friendly database, we can search the compounds by compound name/key word, and we can also search the compound by chemical properties. We can download the compounds in SDF format which is the standard one for various stractural viewers. PubChem has three components, namely PubChem Compounds, PubChem Substances, and PubChem BioAssay described below. 

Fig. 7.30 NMR spectrum of a spiro compound retrieved Horn Spectral Database for Organic Compounds (SDBS) by chemical name search...

The notion, that radicals played an important role in heterogeneous reactions of this type was mentioned at the very beginning of the development of organometallic chemistry Frankland discovered the formation of organozinc compounds when searching for, what in those days were named organic radicals (see chap. 1). 

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