“…Benzimidazole is widely used in antihypertensive, antituberculous, anti-inflammatory, antibacterial, antiviral, analgesic, antihypertensive, antibacterial, and rare applications in cardiovascular diseases. ,− Vitamin B12 consists of benzimidazole, and also thiabendazole, azomycin, chlotrimazole, mebendazole, Omeprazole and albendazole, rabeprazole are the important drugs composed of benzimidazole derivatives. , The synthesis of benzimidazole and quinazoline is 100% atom efficient due to 100% utilization of CO 2 and other substrates . Traditionally, benzimidazole was synthesized from DMF (dimethylformamide) derivatives, formic acid, esters, and methanol. − Benzimidazole was synthesized using a basic medium or strong medium, toxic reagents and high temperatures, but nowadays the synthesis is more environmentally friendly and sustainable by using catalysts. , Another important intermediate used in the pharmaceutical industry is quinazolines-2,4(1 H ,3 H )-diones synthesized by harmful chemicals such as anthranilamide with phosgene, anthranilic acid with urea, and antranilic acid with chlorosulfonyl isocyanate or potassium cyanate (Figure ). , Therefore, there is an urge to synthesize benzimidazole and quinazoline through an environmentally friendly, sustainable process as CO 2 is a low-cost and nontoxic C1 source.…”