Guiding an enzyme all around a ring

Biocatalysis Most compounds of interest for pharmaceuticals, agrochemicals, and cosmetics have many C–H bonds, interspersed with a few carbon bonds to heavier elements that give them their distinct properties. Chemists therefore prize methods that let them selectively modify a variety of C–H bonds. Gilbert et al. report a versatile strategy that relies on a tethered amine to steer an engineered cytochrome P450 enzyme around 11- or 12-membered rings, transforming specific C–H bonds into C–O bonds. Subtle structural variation of the tether through click chemistry tunes the site selectivity. ACS Cent. Sci. 10.1021/acscentsci.7b00450 (2017).