New tools and advancements in chemical structure searches

A number of companies and researchers are working to produce a variety of chemicals with defined structures and functionalities across many industries, including the agriculture, pharmaceutical, general chemical and veterinary sectors. Due to increased research, searches for chemical structures must be simplified in order for IP experts to identify the patent and non-patent documents that they require. As an example, many polymer-based industries are working to introduce new biodegradable polymeric structures as plastic use is gradually being restricted in certain countries. This therefore creates a potential domain for IP research on chemical structures.

The IP industry uses various methods to check whether an invention or product feature is discussed in a patent or published article. Currently, only keyword-based/International Union of Pure and Applied Chemistry (IUPAC) name-based searches are possible, but these can prove insufficient when trying to extract the necessary information from patent and non-patent documents. IP experts therefore need domain-specific technical skills to carry out successful searches.

A chemical structure search is a useful method to identify a chemical compound. However, there are several obstacles to carrying out this kind of search as there is no common method for representing chemical structures in a patent or non-patent document. A chemical compound may be referred to in any format (eg, a systematic chemical name, trivial name, trade or rights holder name or trial preparation code, among others). It could be also presented in image form. At times, a chemical structure is disclosed broadly in Markush forms with numerous possibilities of substitutions and derivatives, which can be difficult to visualise and therefore complicate the search.

IP researchers may encounter difficulties when the invention or product feature covers chemical structures, because none of the conventional strategies are sufficient to capture the relevant art for various IP projects (ie, patentability or validity checks, product clearance searches or infringement studies). However, in recent years, new tools and search services are being introduced, which yield valuable results when conducting chemical structure searches.

Many tools and services now give the option to search for chemical structures when looking for broader chemical information. This information could include the substance’s:

• name;
• attributes (eg, molecular weight or solubility);
• reaction information;
• molecular formula; or
• Chemical Abstract Services (CAS) registry number.

Several free online portals (eg, WIPO-PatentScope) allow searching patent and non-patent articles by using chemical structures. For example, WIPO-PatentScope facilitates sub-structure searches and has 10 million structures interlinked. It provides option of editing structures means that users can access panoramic results of chemical sub-structures in a variety of forms. While these publicly available tools are free and require no training, their search coverage is not comprehensive.

Some third-party databases provide chemical structure searches with an auto-analysis function, which reduces analysis time and can be more flexible. These third-party databases are user-friendly and easy to operate. However, they are very expensive and require expert knowledge to be used. Further, only a limited number of available tools (eg, CAS registry hosted by STN International) have the capability to effectively search Markush structures. Fortunately, many new third-party patent databases (eg, PatSeer) are introducing chemical structure search options to their dashboards.

Comment

Recently developed tools and advancements in chemical structure searching will optimise workflow and improve accuracy and efficiency. To further fulfil the need for chemical structure searches, even more tools are needed to focus on wider parameters, such as data comprehensiveness, ease of operation and cost-effectiveness.