Development of Photoredox Cross-Electrophile Coupling of Strained Heterocycles with Aryl Bromides Using High-Throughput Experimentation for Library Construction.

Microscale high-throughput experimentation was used to develop a photoredox-assisted reductive cross-coupling reaction of aryl halides with strained aliphatic heterocycles facilitated via a ring-opening reaction. This methodology was found to be applicable to medicinally relevant substrates including Boc-protected strained aliphatic heterocycles and (hetero)aryl bromides and was used for compound library construction via parallel medicinal chemistry. Furthermore, the coupling reactions were shown to be scalable to the gram scale by continuous flow reaction. A possible reaction mechanism is also discussed.

Fragment-Based Discovery of a Novel, Brain Penetrant, Orally Active HDAC2 Inhibitor.

Fragment-based ligand discovery was successfully applied to histone deacetylase HDAC2. In addition to the anticipated hydroxamic acid- and benzamide-based fragment screening hits, a low affinity (∼1 mM) α-amino-amide zinc binding fragment was identified, as well as fragments binding to other regions of the catalytic site. This alternative zinc-binding fragment was further optimized, guided by the structural information from protein-ligand complex X-ray structures, into a sub-µM, brain penetrant, HDAC2 inhibitor (17) capable of modulating histone acetylation levels in vivo.