Modern chemical and biological databases

Chemical structure databases and information management systems are a standard item in nearly all chemical structure research environments [1]. They are used to store and retrieve chemical structures as a data type as well as data associated with them. These systems have been designed for, and are customarily used for, single chemical structures that are reasonably well characterized. The recent surge in combinatorial chemistry work has provided a challenge to these systems since the number of chemical structures involved has grown dramatically. In addition, the actual entity studied may be a mixture of tens to millions of structures or more. Such mixtures can often be represented by a generic or Markush structure. This latter challenge will be emphasized in the discussion that follows.