A convenient and biogenetic type synthesis of few naturally occurring chromeno dihydrochalcones and their in vitro antileishmanial activity 

 -  Bioorganic & Medicinal Chemistry Letters, 14(15), p.3913-3916, 2004 .
<br/><br/> 20,20-Dimethyl chromeno dihydrochalcones are very rare in nature as plant secondary metabolites. Recently we have reported three such compounds from the plant Crotalaria ramosissima. Chromeno dihydrochalcones contain a 20,20-dimethyl benzopyran system, which are frequently encountered in many natural products and exhibit a variety of biological activities. We here report the strategy to conveniently synthesize naturally occurring chromeno dihydrochalcones by biogenetic type pyridine or Amberlyst-15 catalyzed chromenylation of dihydrochalcones and in vitro antileishmanial activity of chromeno dihydrochalcones and their intermediates.