butyl, and benzyl ester modified MBH ketones which were shown to have a good performance and provided the respective derivatives 3w-3y in very good yields. Besides, the utility of this protocol was investigated successfully for the synthesis of an analogue of pyrimidobenzimidazole. Towards this, a reaction was carried out using MBH ketone 1a with 1-methyl-2-aminobenzimidazole in place of 2-aminobenzothiazole, following the optimized reaction conditions, leading to the formation of 4a in good yield.