The CAS Patent Markush file
Chemical Abstracts Service (CAS)
MARPAT is a complex and rich data- base of chemical Markush struc-tures from patents cited in the CAplus file. Structure searching in MARPAT allows retrieval of patent records that might be missed by relying solely on other types of pa-tent searching. Covered are more than 1.2 million Markush structu-res from 63 patent authorities.MARPAT includes Markush struc-tures that are representations of organic or organometallic molecu-les. Usually, the Markush structure in a patent consists of a structure diagram with real atoms (C, N, P, etc.) and generic representations and textual descriptions defining the extent of the generic represen-tations. The textual descriptions can be specific or generic.