Synthesis of pyrazines and imidazoles using lemon juice (Citrus limon) as a recyclable catalyst

One-pot four component synthesis of 2,5,6-triaryl pyrazines, 1,2,4,5-tetraaryl imidazoles and 2,2,4,5-tetraaryl imidazoles have been achieved from benzoin, aryl amine, ammonium acetate and aryl ketone /aryl aldehydes using lemon juice (Citrus limon) as an ecofriendly catalyst in good yield under mild conditions. The antibacterial action exhibited by the synthesized compounds against clinical isolates obtained from urinary tract catheters of infected patients is close to the standard drug tetracycline. Recovery of lemon juice after completion of reaction eliminates the need to handle side products, making this process more safe and user friendly.