Tutorial Searching the Internet for Chemical Information

Given the enormous number of resources for chemical information available, many researchers do not have the time to learn the details of the variotis systems, and they end up searching in only a few resources with which they are familiar. This is a dangerous approach Knowing that both fee and non-fee resources are available on the Internet and both hold the desired information, it is prudent to search non-fee systems first and then use proprietary databases to fill data gaps [49]. 

If users are inexperienced in searching for information, they should first consult search engines, meta-databases or portals (Table 5-6). Searchers who are familiar with databases may consult known databases (numeric databases, bibliographic databases, etc.) directly, being aware that they might miss new data sources (see Section 5.18). The reliability and quality of data are only given in peer-reviewed data sources. 

The large seareh engines (Tabic 5-6) generally provide a larger number of hits, hilt often from commercial if not even dubious sources. Yet if information on a new or rare compound is needed, they ean be recommended as a fust choice. The smaller subject engines provide more reliable data, but vary considerably in their results [47]. 

Another approach to obtain an overview on chemical information or on information related to specified topies in chemistry, is to use websites that eontain link lists. These link lists arc usually provided by universities and private persons and are classified into subject areas, Table 5-7 gives an sample of the thousands of link lists in chemistry, and in addition some other valuable URLs that deal with chcmoinformatics. 

All the methods of obtaining information via the Internet presented above carry one risk - dead links. Although a search term may be found by a search engine in its own website-metadata database, the original link to the website could be broken and the information is lost. In this book a conscious effort has been made to limit the URLs and to reduce the web address to the index page of the seiwer, to avoid this sometimes annoying problem. 

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