Imidazole is a heterocyclic compound of five-membered diunsaturated ring structure composed of three carbon atoms and two nitrogen atoms at nonadjacent positions. The simplest member of the imidazole family is imidazole itself, colorless to pale yellow crystalline solid with a weak aminelike odor; soluble in water and alcohol, melts at 89 C, boils at 256 C. Imidazoles are poorly soluble in water generally, but are dissolved in organic solvents, such as chloroform, propylene glycol, and polyethoxylated castor oil. Imidazole ring is found in histidine (an essential amino acid) and histamine, the decarboxylated compound from histamine. Some imidazole compounds inhibit the biosynthesis of ergosterol, required in cell membrane in fungal. They have antibacterial, antifungal, antiprotozoal, and anthelmintic activity. Several distinct phenylimidazoles are therapeutically useful antifungal agents against either superficial or systemic infections. Thiabendazoles which have anthelmintic and antifungal properties are imidazole class compounds. Benzimidazole is a dicyclic compound having midazole ring fused to benzene. Benzimidazole structure is a part of the nucleotide portion of vitamin B₁₂ and the nucleus in some drugs such as proton pump inhibitors and anthelmintic agents. Imidazole has two nitrogen atoms. The one is slightly acidic, while the other is basic. Imidazole and its derivatives are widely used as intermediates in synthesis of organic target compounds including pharmaceuticals, agrochemicals, dyes, photographic chemicals, corrosion inhibitors, epoxy curing agents, adhesives and plastic modifiers. Some imidazole analogues which contain nitrogen in five-membered ring structure are:

Imidazole is a heterocyclic compound of five-membered diunsaturated ring structure composed of three carbon atoms and two nitrogen atoms at nonadjacent positions. The simplest member of the imidazole family is imidazole itself, colorless to pale yellow crystalline solid with a weak aminelike odor; soluble in water and alcohol, melts at 89 C, boils at 256 C. Imidazoles are poorly soluble in water generally, but are dissolved in organic solvents, such as chloroform, propylene glycol, and polyethoxylated castor oil. Imidazole ring is found in histidine (an essential amino acid) and histamine, the decarboxylated compound from histamine. Some imidazole compounds inhibit the biosynthesis of ergosterol, required in cell membrane in fungal. They have antibacterial, antifungal, antiprotozoal, and anthelmintic activity. Several distinct phenylimidazoles are therapeutically useful antifungal agents against either superficial or systemic infections. Thiabendazoles which have anthelmintic and antifungal properties are imidazole class compounds. Benzimidazole is a dicyclic compound having midazole ring fused to benzene. Benzimidazole structure is a part of the nucleotide portion of vitamin B₁₂ and the nucleus in some drugs such as proton pump inhibitors and anthelmintic agents. Imidazole has two nitrogen atoms. The one is slightly acidic, while the other is basic. Imidazole and its derivatives are widely used as intermediates in synthesis of organic target compounds including pharmaceuticals, agrochemicals, dyes, photographic chemicals, corrosion inhibitors, epoxy curing agents, adhesives and plastic modifiers. Some imidazole analogues which contain nitrogen in five-membered ring structure are: