Versatile Computer Techniques for Searching by Structural Formulas, Partial Structures, and Classes of Compounds

The principles of the topological encoding of formulas and machine searching are briefly described. These methods have been developed to the point where it is now possible to carry out a computer search for a given structural fragment without the risk of false drops. It is also possible to carry out searches whose requirements, while well‐defined and readily used by chemists, cannot be represented exclusively by element symbols and chemical bonds.