Imidazole is a five-membered heterocyclic compound with two nitrogen atoms. Hydrogen atoms move between two nitrogen atoms, so there are two tautomers. It is not only a component of histidine in organisms, but also a component of ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) purine. Imidazole molecule itself has the characteristics of good electron transfer and easy functionalization. Many compounds containing imidazole ring play an important role in the field of medicine and pesticide because of their good biological activity. Many drugs also contain imidazole rings, such as nitroimidazole and imidazole antifungal agents. In recent years, imidazoles have become a research hotspot in the synthesis and application of new nitrogen-containing heterocyclic compounds at home and abroad. Imidazole ring structure exists widely in biomolecules, such as histidine and corresponding Holmont histamine.
The resonance structures of imidazole
There are imidazole functional groups in many important biomolecules. The most common is histidine, which contains the side chain of imidazole. Histidine appears in many proteins and enzymes, and it is also an important structural component of hemoglobin, which is of great significance to its coordination ability. At the same time, it has been found that some drugs can selectively act on the imidazoline receptor and reduce the effect on the a2 receptor, thus avoiding some central side effects of clonidine, such as Moxonidine.
One use of imidazole is to purify His tagged proteins in metal chelate affinity chromatography ((IMAC)). The label protein binds to the nickel ion medium in the bead hole on the surface of the chromatography column, and the excess imidazole elutes the label protein coordinated with nickel through the chromatography column to obtain the target protein with high purity. The (PBIS)derivative of 4H-pyrrolo[1,2-a]benzimidazole is a kind of nitrogen heterocyclic compound. It has been found that the substituents of-CN and-CO2 Et on the PBIS pyrrole ring have good fluorescence color aid, while-COOPh and-COOMe play a quenching role.
Imidazolines are used as herbicides: Imidazolinones are a kind of highly active broad-spectrum herbicides, and excellent varieties have been developed, such as imidazolide, fenpromaquine and so on. Used as a fungicide: fruit green, Etem, etc.
Imidazole and its derivatives are a very important kind of epoxy resin curing agent, especially in recent years, with the development of the electronic industry, the amount of imidazole epoxy resin curing agent has increased by 15% to 20% every year. At present, the amount of imidazole and its derivatives has accounted for more than 90% of the total production of imidazole and its derivatives.