trans-2-(Azaarylsulfanyl)cyclohexanol derivatives as potential pH-triggered conformational switches

A series of trans-2-(azaarylsulfanyl)cyclohexanol derivatives, structurally similar to previously studied trans-2-amino-cyclohexanols, were synthesized through epoxide ring opening under basic conditions with sodium tetraborate as a catalyst. 1H NMR spectroscopy was used to elucidate the conformational equilibrium in various solvents and its acid-induced change due to stabilization of the conformer with the azaarylsulfanyl and hydroxy groups in equatorial position by an intramolecular hydrogen bond and electrostatic interactions.