Properly designed trans-2-aminocyclohexanols possess a negative allosteric cooperativity and can serve as powerful conformational pH-triggers. Their protonation leads to a conformational flip due to a strong intramolecular hydrogen bond. This 'impulse' is mechanically transmitted by the cycle to induce a conformational change of a remote site, thus altering its properties. Variation of NR2 groups allows a tuning of the conformational equilibrium, which was studied by NMR. These triggers were used in pH-sensitive lipid vesicles for drug and gene delivery.
Available at: http://works.bepress.com/xin-guo/60/