Language Structures- GENSAL

Barnard, J. M., M. F. Lynch, and S. M. Welford. 1981. Computer storage and retrieval of generic structures in chemical patents. 2. GENSAL, a formal language for the description of generic chemical structures. J. Chem. Inf. Comput. Sci. 21(3) 151—161. 

Barnard, J.M. Lynch, M.F. Welford, S.M. Computer Storage and Retrieval of Generic Chemical Structures in Patents, Part 2, GENSAL, A Formal Language for the Description of Generic Chemical Structures. J. Chem. Inf. Comput. Sci. 1981, 21, 151-161. 

Another example is GENSAL, which provides a means for the representation of generic queries in an experimental system for the storage and retrieval of the Markush structures that occur in chemical patents. Here, the language allows the specification of lists of alternative substituents, of variant positions of substitution on rings, and of ranges of numbers of atoms in carbon chains. Thus, these lists reflect the very wide range of types of structural description that are found in patents for chemical substances. 

Since we have the GENSAL language (see Figure 2) for description of Markush structures , and software for translation of them into machine internal representations, we are able to derive search representations automatically. Great... 

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