Benzimidazole

Benzimidazole

Names
Preferred IUPAC name 1H-1,3-Benzimidazole
Other names 1H-Benzo[d]imidazole
Identifiers
CAS Number	51-17-2 Y
3D model (JSmol)	Interactive image
Beilstein Reference	109682
ChEBI	CHEBI:41275 Y
ChEMBL	ChEMBL306226 Y
ChemSpider	5593 Y
DrugBank	DB02962
ECHA InfoCard	100.000.075
EC Number	200-081-4
Gmelin Reference	3106
KEGG	C02009 Y
PubChem CID	5798
UNII	E24GX49LD8 Y
CompTox Dashboard (EPA)	DTXSID8024573
SMILES c1ccc2c(c1)[nH]cn2
Properties
Chemical formula	C7H6N2
Molar mass	118.14 g·mol−1
Melting point	170 to 172 °C (338 to 342 °F; 443 to 445 K)
Acidity (pKa)	12.8 (for benzimidazole) and 5.6 (for the conjugate acid)[1]
Hazards
GHS labelling:
Pictograms	Template:GHS07
Signal word	Warning
Hazard statements	H302, H315, H319, H335
Precautionary statements	P261, P264, P270, P271, P280, P301+P312, P302+P352, P304+P340, P305+P351+P338, P312, P321, P330, P332+P313, P337+P313, P362, P403+P233, P405, P501
Safety data sheet (SDS)	External MSDS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y verify (what is YN ?)
Infobox references

Benzimidazole is an organic compound. It has the chemical formula C₇H₆N₂. It is made of a benzene ring that shares a side with an imidazole ring. Like benzene and imidazole, it is an aromatic compound.

Chemicals that have the benzimidazole structure are called benzimidazoles. The chemical benzimidazole has few uses, but many benzimidazoles are used as drugs, plastics and dyes.

Some examples of benzimidazoles:

• Angiotensin II receptor blockers such as azilsartan, candesartan, and telmisartan.
• Anthelmintic agents such as albendazole, ciclobendazole, fenbendazole, flubendazole, mebendazole, oxfendazole, oxibendazole, triclabendazole, and thiabendazole.
• Antihistamines such as astemizole, bilastine, clemizole, emedastine, mizolastine, and oxatomide.
• Benzimidazole fungicides such as benomyl, carbendazim, fuberidazole, and thiabendazole.
• Nitazenes, or Benzimidazole opioids, such as bezitramide, brorphine, clonitazene, etodesnitazene, etonitazene, etonitazepipne, etonitazepyne, isotonitazene, metodesnitazene, and metonitazene.
• Proton-pump inhibitors such as dexlansoprazole, esomeprazole, ilaprazole, lansoprazole, omeprazole, pantoprazole, rabeprazole, and tenatoprazole.
• Typical antipsychotics such as benperidol, clopimozide, droperidol, neflumozide, and oxiperomide, and pimozide.
• Benzimidazole can also be found in abemaciclib, bendamustine, dabigatran, daridorexant, and glasdegib.

When printed circuit boards are manufactured (or made), benzimidazole can be used as an organic solderability preservative. (When that kind of preservative gets used, it can protect copper contacts (for years), until the contact gets soldered.)