Int. J. Information Technology and Management, Vol. 1, No. 1, 2002 69 Copyright © 2002 Inderscience Enterprises Ltd. Chemoinformatics: a tool for modern drug discovery M. Karthikeyan and S. Krishnan SMIS Division, National Chemical Laboratory, Pune – 411 008, India Fax: +91-20-5893973 E-mail: karthi@ems.ncl.res.in krish@ems.ncl.res.in Abstract: The exponential rise in costs despite numerous years of hard work has hampered the proficiency, productivity and efficiency of this research. Nevertheless, due to in silico and computational advances, databanks have accelerated the decoding of genes sequences to 3D complex biomolecules in a very short time span. The important advantage of a computational technique is its ability to eliminate unpromising lines of inquiry early in the discovery process. With the help of the combinatorial library and database mining, it is possible to undertake a specific chemical reaction on various identical reactants in all possible combinations. Chemoinformatics will help to identify promising molecules of greater importance at earlier stages viz., to eliminate failures at the latter stages. Keywords: Chemoinformatics; computational chemistry; virtual library of molecules; knowledge based computing; drug discovery; in silico synthesis. Reference to this paper should be made as follows: Karthikeyan, M. and Krishnan, S. (2002) ‘Chemoinformatics: a tool for modern drug discovery’, Int. J. Information Technology and Management, Vol. 1, No. 1, pp.69–82. Biographical notes: M. Karthikeyan is a scientist in the Scientific Management Information System Division, National Chemical Laboratory, Pashan Rd., Pune 411 008, India. After graduating in chemistry from Pondicherry University, he carried out his research in the area of synthetic organic chemistry at the national chemical laboratory and obtained his PhD from the Pune University. His major interests include designing knowledge management tools to handle digital databases with chemical structure information. He received two student awards in this area for originality and novelty from the Chemical Structure Association. S. Krishnan is the head of the Management and Information Services Division, National Chemical Laboratory, Pashan Rd., Pune 411 008, India. He obtained his PhD in biophysics from the Indian Institute of Science, Bangalore. After a postdoctoral fellowship at the University of California, Santa Cruz, he worked in the Scientific Information group at Ciba-Geigy, Basel, Switzerland. His major interests include chemical information and digital libraries. 1 Introduction Competition and cost has changed the drug design paradigm from the hit and trial approach to the drug design approach allowing the tailormade design of active molecules. This has resulted in both targeted drug discovery and reduced drug development cycle