Heterocycles beyond the DHPMs

This reaction also allows the synthesis of other interesting scaffolds with a wide range of biological activities, among them are coumarins and thiocoumarins [64] and their derivatives that display a remarkable array of biochemical and pharmacological actions and are abundant in numerous natural products. 

On the basis of aU the experimental results, an acceptable mechanism for the synthesis of 5-methylmercaptothio-carbonyl-4-aryl-3,4-dihydropyrimidin-2(l//)-ones 53 and substituted 2H-chromen-2-thiones 55 is disclosed in 

SCHEME 9.18 Ionic liquid-catalyzed Biginelli reaction. 

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