Working Paper The DENDRAL Project: A Short Summary Bruce Buchanan Stanford University March, 1977

The DENDRAL research project was started in 1965 by Professors J. Lederberg and E.A. Feigenbaum and now includes Professor C. Djerassi in the Chemistry Department and about 20 other persons in Computer Science, Chemistry and Genetics. There are several aspects to the whole project, including research in chemistry and genetics, development of new chemical instrumentation and supporting computer programs, as well as artificial intelligence research. We have had two main computer science goals in this work: to study scientific inference and to aid working scientists. The two programs described below illustrate these concerns. Heuristic DENDRAL The Heuristic DENDRAL Program is designed to aid organic chemists determine the molecular structure of unknown compounds. Parts of the program have been highly tuned to work with experimental data from an analytical instrument known as a mass spectrometer. Mass spectrometry is a new and still developing analytical technique. It is not ordinarily the only analytic technique used by chemists, but is one of a broad array of analytic techniques including NMR, IR, UV, and "wet chemistry" analysis. It is particularly useful when the quantity of the sample to be identified is very small, for mass spectrometry requires only micrograms of sample.