Carboxyl/imidazole

Etomidate is a carboxylated imidazole that can be used for induction of anesthesia in patients with limited cardiovascular reserve. Its major advantage over other intravenous anesthetics is that it causes minimal cardiovascular and respiratory depression. Etomidate produces a rapid loss of consciousness, with minimal hypotension even in elderly patients with poor cardiovascular reserve. The heart rate is usually unchanged, and the incidence of apnea is low. The drug has no analgesic effects, and coadministration of opioid analgesics is required to decrease cardiac responses during tracheal intubation and to lessen spontaneous muscle movements. Following an induction dose, initial recovery from etomidate is less rapid (< 10 minutes) compared with recovery from propofol. 

When an amine is oxidized, electrons pass from the amine to the disulfide and then to the flavin. The formation in MAO of a carboxyl-imidazole-disulfide triad, similar to that demonstrated for disulfide oxidoreductases, would result in an increased positive charge on the disulfide,... 

Candour, R. D., Nabulsi, N. A. R., and Fronczek, F. R., Structural model of a short carboxyl-imidazole hydrogen bond with a nearly centrally located proton Implications for the Asp-His dyad in serine proteases, J. Am. Chem. Soc. 112, 7816-7817 (1990). 

Amines carboxylates imidazole Imidazole cysteine glutamic acid SH... 

Etomidate is the ester of a carboxylated imidazole, with a log P of 3 and a weak base pKa of 4.5, that is available as the D-isomer solubilized in 35% propylene glycol for intravenous injection in addition to being available for reotal administration. It is a potent, short-acting hypnotic agent (<3 min) without analgesic activity and with a rapid onset of action. This agent is useful for the induction of anesthesia in hemodynamically unstable patients prone to hypotension because of hypovolemia, coronary artery disease, or cardiomyopathies. Recovery is similarly rapid following... 

Amphoteric surfactants are divided into two groups based on their response to pH. One class of compounds that contain carboxylated imidazoles and A-alkyl betaines are zwitterionic at pHs at, and above, their isoelectric points and cationic at lower pHs. Sulfobetaines and phosphobetaines, on the other hand, exhibit zwitterionic characteristics as the anionic portion is dissociated at all pHs. Although the former are the major ingredients in many baby shampoos or those products that provide mildness, they also function as foam and viscosity enhancers when utilized as secondary surfactants, having good water solubility over a wide pH range. ° ... 

As outlined in Sect. 5.1, the inclusion of two molecules of hydrating water enhanced the belief in the extension of the initially assumed similarity of the carboxyl-imidazole pair to the respective functions in serine proteases. The presence of two to four water molecules (or assigned as such) in this family of enzymes and in... 

In parallel, various affinity systems were also investigated such as the specific interactions between maltose-binding protein and positively charged polypyrrole film or a metal affinity immobilization concept based on the coordination of polyhistidine-tagged proteins or DNA to metal centers such as Ni " or chelated by polypyrrole films containing carboxylate, imidazole, or nitrilotriacetic acid groups (NTA) [15]. 

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