Modulating the selectivity of inhibitors for prolyl oligopeptidase inhibitors and fibroblast activation protein-α for different indications.

We have previously described several different chemical series of bicyclic prolyl oligopeptidase (POP) inhibitors as probes for neurodegenerative diseases that demonstrated nanomolar activity in vitro and submicromolar activity in cellulo. The more recent implication of POP in cancer, together with homologous fibroblast activation protein α (FAP), implicated in tumor growth, led us to consider developing POP/FAP dual inhibitors as a promising strategy for the development of cancer therapeutics. At this stage, we thought to evaluate the requirements for selectivity of inhibitors for POP over FAP and to evaluate molecular platforms that would enable the development of selective POP and dual POP/FAP inhibitors.

Design, synthesis and in vitro evaluation of novel SARS-CoV-2 3CL covalent inhibitors.

Severe diseases such as the ongoing COVID-19 pandemic, as well as the previous SARS and MERS outbreaks, are the result of coronavirus infections and have demonstrated the urgent need for antiviral drugs to combat these deadly viruses. Due to its essential role in viral replication and function, 3CL (main coronaviruses cysteine-protease) has been identified as a promising target for the development of antiviral drugs. Previously reported SARS-CoV 3CL non-covalent inhibitors were used as a starting point for the development of covalent inhibitors of SARS-CoV-2 3CL.

Targeting MYC: From understanding its biology to drug discovery.

The MYC oncogene is considered to be a high priority target for clinical intervention in cancer patients due to its aberrant activation in more than 50% of human cancers. Direct small molecule inhibition of MYC has traditionally been hampered by its intrinsically disordered nature and lack of both binding site and enzymatic activity. In recent years, however, a number of strategies for indirectly targeting MYC have emerged, guided by the advent of protein structural information and the growing set of computational tools that can be used to accelerate the hit to lead process in medicinal chemistry.

Design and discovery of boronic acid drugs.

Research related to boronic acids, from synthetic development to materials to drug discovery, has skyrocketed in the past 20 years. In terms of drug discovery, the incorporation of boronic acids into medicinal chemistry endeavours has seen a steady increase in recent years. In fact, the Food and Drug Administration (FDA) and Health Canada have thus far approved five boronic acid drugs, three of which were approved in the past four years, and several others are in clinical trials.

Discovery of covalent prolyl oligopeptidase boronic ester inhibitors.

Over the past decade, many drug discovery endeavors have been invested in targeting the serine proteases prolyl oligopeptidase (POP) for the treatment of Alzheimer's and Parkinson's disease and, more recently, epithelial cancers. Our research group has focused on the discovery of reversible covalent inhibitors, namely nitriles, to target the catalytic serine residue in this enzyme. While there have been many inhibitors discovered containing a nitrile to covalently bind to the catalytic serine, we have been investigating others, particularly boronic acids and boronic esters, the latter of which have been largely unexplored as covalent warheads.