Markush Structures Derwent

Suhr, C von Harsdorf, E. Dethlefsen, W. Derwent s CPI and IDC s GREMAS Remarks on their Relative Retrieval Power with Regard to Markush Structures . In Proceedings of a Conference organised by the Chemic Structure Association at the University of Sheffield, England, 26-29 March 1984. 

The WPIM file corresponds to Derwent World Patents Index (DWPI) online file, and therefore includes documents from all of the countries that Derwent normally covers. Indexing for WPIM began in 1987, and since 1987, Derwent has double indexed all chemical patents with both the fragmentation codes and WPIM indexing. Specific structures are indexed if they are not part of a Markush structure in the same patent document. Polymers are not indexed in detail in the WPIM database. Polypeptides of 10 or more amino acids are indexed in a separate non-Markush database and are not included in WPIM. All four online services that carry the DWPI also have the WPIM accession numbers. WPIM indexes patents from all countries in the Derwent database, but it is available to subscribers only. 

Apart from MARPAT there is another database describing Markush structures, it is the Markush system of Derwent in combination with the database PHARMPAT of the Institut National de la Propriete, which is offered exclusively by the host QUESTEL, where it is searchable using the Markush-Darc system. Markush-Darc is a joint venture by Derwent Publications Ltd., the Institut National de la Propriete Industrielle and QUESTEL. It has been available since 1989 online and contains two files ... 

There is a gateway to QUESTEL, making the Derwent file for Markush structures, Markush Dare, accessible to the searcher (Sect. 7.8). 

QUESTEL and STN are the only hosts providing the graphic structure search using the Generic DARC System. Under the same command mode Derwent s Markush Dare file, containing the Markush structures is available. Regrettably, there is no nomenclature file text on QUESTEL which would allow searches for substance names und molecular formulae. 

WPIM (World Patents Index Markush), produced by Derwent Publications, Ltd., contains the specific and generic structure records for compounds in the patents included in Derwent Sections B (Farmdoc), C (Agdoc), and E (Chemdoc) since 1987. Sources include patents from 29 industrialized countries as well as European and PCT patents and also items from Research Disclosure and International Technology Disclosures. The compound numbers of relevant references found in WPIM can be searched in Derwent s WPI database to retrieve the corresponding bibliographic information. 

Whatever the search software offered, however, the database was of utmost importance. The DARC system not only offered a means to search generic structures in the short term, it also offered a way to record all of the information about structures found in patents, through a new and flexible input system. This capability was of incredible import to Derwent we could build a database that would not only serve the users today, but in future could be of more utility as search software was further developed. As opposed to the fragmentation code, there should never be a question of time-ranging. Moreover, though we assume that Markush DARC is a system not only of today but of tomorrow, we are building a database that can be converted and adapted to other search systems that may be offered by other organisations. 

Segment 1 denotes that a specific structure has been claimed in a patent in isolation, or as one of a very small group of specific compounds. Derwent is using Segment 1 as an efficiency factor in indexing, and in presentation to the user. For example, if there are 1,000 patents on production of aniline, the user would only wish to see one graphic aniline record, along with any representations of aniline as a possibility of a Markush. 

CAS = chemical abstracts service CDB = IFI/Plenem comprehensive code DWPI = Derwent world patents index INPI = Institut national de la propriete industrielle (the french patent office, producer of pharmsearch) MARPAT = chemical abstracts service database of Markush chemical structures from patents MDARC = Markush DARC MPHARM = pharmsearch Markush file, produced by INPI WPIM = world patents index Markush file. 

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