For 10 points, identify this heterocyclic functional group whose structure is a cyclopentadiene with two nitrogens, the functional group that forms the side chain of histidine.
A reaction named for Bamberger acylates these compounds via a ring-opening step. The earliest synthesis of these compounds involved a condensation of an aldehyde with an alpha-dicarbonyl compound such as glyoxal using 2 equivalents of ammonia in the presence of alcohol; that reaction is named for Radziszewski and Debus. This functional group is most commonly found in drugs such as proton pump inhibitors. It has a pKa of 7, and its nucleophilic character makes it an ideal base for ester hydrolysis. It is much more basic than related compounds such as pyrrole because the sp2 electrons on one of the nitrogens are not delocalized into the pi-system. For 10 points, identify this heterocyclic functional group whose structure is a cyclopentadiene with two nitrogens, the functional group that forms the side chain of histidine.
A reaction named for Bamberger acylates these compounds via a ring-opening step.
imidazole [or C3H4N2; or 1,3-diazole; or 1,3-diazacyclopenta-2,4-diene; or glyoxaline]