Introducing covalent warheads on spirocyclic sp2-sp3 fragments by innate C-H functionalization

Org Biomol Chem. 2023 Nov 29;21(46):9230-9235. doi: 10.1039/d3ob01746j.

Abstract

Sp2-sp3 fragments play a vital role in fragment-based drug design (FBDD). Strategies to chemically modify them and efficiently access libraries of these compounds have been goals of the highest priority in the last decades. In this work, a series of sp2-sp3 fragments was synthesized and validated for that purpose, based on their measured physical-chemical properties. Selective C-H cyanation and allylation of these fragments was demonstrated by simple heating in presence of an appropriate hydrogen-atom transfer reagent and a radical acceptor. These conditions enabled a streamlined access to covalent fragments in a single step, by direct introduction of the desired covalent binder. Preliminary results on vinylation, as well as late-stage functionalization of a drug analogue were disclosed.