Chemical Information Sources/Guides

Introduction

Most students of chemistry know about CambridgeSoft's ChemBioFinder, an example of a Web guide and handbook produced by a reliable company that carefully selects the Web sources to index via ChemBioFinder. Other Web guides and guides to printed literature are introduced in this lesson. Works that help you decide what secondary or primary tools to use or works that actually help you use those tools are referred to as GUIDES, sometimes called TERTIARY tools. These may help:

• find relevant tools to solve an information problem
• learn how to use those tools.

Guides are found as printed books, directories of databases, directories of resources on the Internet, "how-to" manuals that accompany software or databases, and in several other formats, including online help files.

Database Summary Sheets for Command Driven Searches

A particular type of guide is the DATABASE SUMMARY SHEETS provided by the vendors or producers of online databases. VENDORS are commercial entities that lease database content from DATABASE PRODUCERS and sell access to those files over public or restricted-access communication lines. The vendor Dialog Information Services makes available their "bluesheet" database summary sheets. STN's database summary sheets are also available as Internet files. Look at the database summary sheets for the LCA (Chemical Abstracts Learning File on STN) and LREGISTRY (Chemical Abstracts chemical dictionary learning file on STN). Note the different search and display possibilities that are possible with these files and how the summary sheets help you select the right way to enter the search if you were using the native command language of the STN system, STN Messenger. Nowadays, most chemical searchers don't have to know anything about the STN command language because Chemical Abstracts Service's SciFinder product does much of that work for you behind the scenes. Nevertheless, some examples of the STN Messenger command language searches are included throughout this work in order to demonstrate the power of command-language searching. Command line searching on the vendor systems is still very much in demand in industry because it allows experienced online searchers to be much more precise with their search strategies.

It is important to note that the same database may be available on several different vendors' systems, sometimes with different components of the database or different time periods available, and most likely different codes for the various fields of data in the records. For example, STN International offers the most data for the Chemical Abstracts database in its CA, Registry, and other files. These provide the text of the abstracts, the drawings of the chemical structures, enhanced indexing, and the capability to use the chemical structure as a search key. The CA and Registry databases and others are searchable in SciFinder, although it may be transparent to you when you are in one database or the other. Even a single vendor may offer multiple access points to certain databases, some designed for experienced searchers and others, for novices.

Designed to serve the chemical information needs of undergraduate students, CA Student Edition contains references from January 1, 1967 to the present from the Chemical Abstracts database. Included are references and abstracts from a select ""&results=paged&PageSize=25&B1=Search list of a few hundred journals and review serials, as well as over 200,000 chemistry dissertations. Searches may be performed by author names, subject words (including chemical substance names), and CAS Registry Numbers, as well as other search strategies. No structure searching is possible in the database.

Database Guides and Online Aids for Database Selection

There are comprehensive printed directories of commercially available databases and an ever-increasing number of guides to free resources on the Internet, e.g., Chemistry Databases on the Web. Also, many people have compiled guides to chemistry resources on the Internet.

Another approach to selecting a database is to let the commercial vendor's search system analyze which databases among their offerings have information relevant to your search. Dialog Information's DIALINDEX identifies which DIALOG files have information on a given topic; INFODEX is an online index to the contents of more than 30 databases on the Chemical Information System, a collection of environmentally-oriented databases. The corresponding type of search on STN would be done with the STNindex feature. The STNGuide file is a database of STN Summary Sheets. It can assist in selecting the proper database to search. Here is a search on STNGUIDE to identify databases that have information on organometallic compounds. The results are brief descriptions of the databases that include organometallic compounds in their coverage.

Comprehensive Chemistry Guides

A past champion of chemical literature instruction, George Gorin, once compiled a list of guides to the chemical literature that began with a German book by Ostwald published in 1919 and included works by over a dozen other authors whose books appeared up to 1983. The classic work of this type was Mellon's Chemical Publications which came out in five editions between 1928 and 1982. Remember that databases have been around only a few decades, whereas the printed archive of chemical knowledge extends back in time several centuries. Much of the printed literature of chemistry may never be available on the Web. A more recent printed guide is Andrew Foss's Library Handbook for Organic Chemists (Chemical Publishing Company, 2000). The "Search Orientation Table" in that work relates questions to appropriate sources. You will find there the tables of contents of standard printed works such as the treatise Comprehensive Organic Chemistry. Here is a link to a list of printed guides in science, technology, and medicine. Chemical information teaching resources are being deposited in XCITR, a cooperative site sponsored by the American and German chemical societies and FIZ Chemie Berlin.

There is an increasing amount of chemical information available on the Internet. A powerful guide to chemical data, including structures, on the Web is ChemBioFinder from CambridgeSoft. In addition to linking chemical substances to Web pages on the Internet, ChemBioFinder is also a handbook with reliable chemical data for many compounds.

A searchable guide to both printed and computer-based reference tools is the Chemistry Reference Sources Database (CRSD).

Search Strategy Formulation

A SEARCH STRATEGY is a map of a course of action in searching that ought to result in finding an answer to a chemical information problem. It could involve using library, free internet, and/or commercial database resources. A search strategy includes such tasks as:

• identifying the main concepts and other parameters for the search (time period, types of documents to be retrieved, other factors to be considered, e.g., immediacy of the need for the answer)
• drawing up a list of terms and other search keys to be used (e.g., chemical structures, authors' names, chemical names, etc.)
• deciding what sources are most likely to have the answers
• searching the printed works or databases until the answer is found or you are satisfied that no answer can be found in the available resources.

For the third step, the works in this chapter will help you make appropriate choices.

Summary

The literature of chemistry is so huge that it can be a bewildering task to decide just where to start. The guides that have been developed over the years can remove most of the uncertainty about the best path to find an answer to a chemical question. One thing to keep in mind, however, is that some chemical questions will not have answers in the literature. It is up to the searcher to decide how much time and effort should be used in the pursuit of an answer. A well thought-out strategy, based on the information gleaned from the guides, can make the search much more fruitful.

SIRCh Link for Guides

Problem Set on this topic