21. This compound is a protonated morpholine molecules. 22. Some studies of the C NMR in particular favored interpretation via the protonated nortricyclene structure. 23. Both the protonated and neutral forms lessen the membrane permeability of the nerve to sodium. 24. In an acid environment, the inactive drug is protonated and rearranges into its active form. 25. The negatively charged glucose-bound oxygen is then protonated by His119 forming a free glucose. 26. Protonated bipyridine adopts a cis conformation.27. To close the fructose ring, the reverse of ring opening occurs and the ketose is protonated . 28. The hydroxyl is protonated using hydrogen from formic acid, which allows for water molecule to leave. 29. Thus the mechanism was proposed to occur via attack of the protonated carbonyl with the forming enol. 30. Under strongly acid conditions periodic acid can be protonated to give the " orthoperiodonium " cation.
