Three patent applications are reviewed that were published during 2015, including (1) an application by the pharmaceutical company, Novartis, for a process for the antimalarial drug candidate cipargamin, (2) an application by the University of Bradford, UK, for a solid-to-solid crystallization process to generate metastable polymorphs, and (3) an application by fine chemical company Cambrex for a new route to the antiepileptic (R)-lacosamide. Each application discloses previously unpublished chemistry. While medicinal chemists are avid followers of the patent literature in order to keep abreast of potential overlapping chemical space relevant to their particular programs, process chemists are generally indifferent to the patent literature. First of all, patents are not scientific publications but are documents written for legal and business purposes. As such, the scientific discussion is generally limited to just what is needed to support the claims with a focus on demonstrating what is new and useful about the invention. Other scientifically interesting aspects of the work that are not directly relevant to the claims are generally not discussed. Second, since published patent applications are not peer-reviewed and have yet to be reviewed by a patent examiner, the chemistry as described is often not reproducible, and many (or all) claims may not ultimately be granted. While irreproducibility is an issue with literature publications as well, patent applications pose a higher risk since much less analytical data and experimental details are provided than with peer-reviewed publications. Patent applicants are required to provide just enough detail such that one "skilled in the art" can reproduce the procedures, but often the sketchy experimental procedures leave much to imagination. The lack of scientific discussion in a patent application can be frustrating. In a literature publication, for example, if an asymmetric reaction is presented, data would be provided on ee's or de's under differing conditions, and the authors would likely provide perspective on how they arrived at the optimum conditions. But in a patent, no such context is provided-only the end results are presented. The discussion section of a patent, referred to as the specification or disclosure, is often focused on covering the widest scope possible for the chemistry and is not a scientific discussion of the results. Pertinent details are often missing, bringing up many questions for any reader who wishes to consider the chemistry for their particular application. With these caveats, however, patent applications are in many cases important scientific contributions. Since some companies do not encourage or allow publication by their scientists in peer-reviewed journals, patents may be the only disclosure of a synthetic process for a drug or drug candidate or a newly developed methodology. With this in mind, our goal is to review patents and patent applications that offer novel, important, and practical chemistry that is not covered in the scientific literature. In this article, three patent applications are reviewed that were published during 2015, each disclosing previously unpublished chemistry: · A process for the antimalarial drug candidate cipargamin, filed by the pharmaceutical company Novartis; · A new route to the antiepileptic (R)-lacosamide, filed by the fine chemical company Cambrex; and · A solid-to-solid crystallization process to generate metastable polymorphs, filed by the University of Bradford, UK. © 2016 American Chemical Society.
