Diastereoselective and Efficient Synthesis of Indeno[2″,1″: 4′,5′]furo[3′,2′: 5,6]pyrido[2,3‐ d ]pyrimidine‐2,4,6(1 H ,3 H )‐trione and 6‐(2,3‐Dihydro‐2‐hydroxy‐1,3‐dioxo‐1 H ‐inden‐2‐yl)‐5,8‐dihydropyrido[2,3‐ d ]pyrimidine‐2,4,7(1 H ,3 H ,6 H )‐trione Derivatives

A diastereoselective synthesis of some new N ‐containing heterocyclic compounds, indeno[2″,1″: 4′,5′]furo[3′,2′: 5,6]pyrido[2,3‐ d ]pyrimidine‐2,4,6(1 H ,3 H )‐trione derivatives, is presented. Products were obtained in good to excellent yields by the reaction of amino(thio)uracils with 2‐hydroxy‐2‐(3‐oxobut‐1‐en‐2‐yl)‐2 H ‐indene‐1,3‐dione in AcOH under reflux conditions. Also, a simple and efficient method was introduced for the synthesis of 6‐(2,3‐dihydro‐2‐hydroxy‐1,3‐dioxo‐1 H ‐inden‐2‐yl)‐5,8‐dihydropyrido[2,3‐ d ]pyrimidine‐2,4,7(1 H ,3 H ,6 H )‐triones via the reaction of amino(thio)uracils and methyl 2‐(2,3‐dihydro‐2‐hydroxy‐1,3‐dioxo‐1 H ‐inden‐2‐yl)acrylate. The simple procedure and easy work‐up, high yields, short reaction times, and diastereoselectivity of the reaction are salient features of this method. The structural assignments are supported by 1 H‐ and 13 C‐NMR, and X‐ray crystallography data.