Abstract
The effective and high yielding synthesis of poly-functionalized pyrimidines, using multicomponent reactions (MCRs), is imperative in organic and medicinal chemistry. The classic Biginelli reaction is a typically one-pot three-component cyclocondensation reaction involving an aldehyde, a β-ketoester and urea, resulting in the construction of multi-functionalized 3,4-dihydropyrimidin-2(1H)-ones (DHPMs). In recent years, other active methylene compounds, various derivatives of urea and diversely substituted aldehydes have also been used, resulting in the preparation of a new series of various novel dihydropyrimidinones via the Biginelli-Type Reactions (BTRs) or modified Biginelli reactions (MBRs). In this review, we try to underscore the recent advances in BTRs or MBRs.
Keywords: Biginelli reactions, multicomponent reactions, one-pot reaction, Biginelli-type reactions, modified Biginelli reactions, β- ketoester, urea, dihydropyrimidinones.
Graphical Abstract
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