Synthesis of Novel Spiro Uracil-1,4-dihydropiridine via One-Pot, Three Component Reaction

Green synthesis of spiro uracil-1,4-hydropyridine has been reported via one-pot three componentreaction in the presence of p-TSA as catalyst. Spiro oxindoles are classified as an importantstructural motif due to their distribution in diverse natural products, biologically andpharmaceutical activities such as the influenza virus [1], as inhibitors of the denque virus [2]and anti-cancer agents [3]. Therefore, we conducted a series of examination the chemistry of5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinolone-1,2-dione, in which the reactivity of the ketonecarbonyl group of the 2-keto-amide unit was utilized. Thus, we were able to construct variousspiro[3,3’-oxindoles] via three and four component combination [1-3]. Amongst, spirouracil-1,4-dihydropyridine moieties have shown important biological and medicinal activities. As apart of our ongoing interest in this context, we reported a simple and facile synthesis of a newtype of spiro uracil-1,4-dihydropyridines (4) in the presence of p-TSA as catalyst (Figure 1)from starting 6-aminouracil (2), 3-oxo-3-phenyl propannitrile (3) and 5,6-dihydro-1Hpyrrolo[3,2,1-ij]quinolone 1,2(4H)-dione (1) in environmentally friendly solvent, EtOH/H2O.The key features confirming the structures can be illustrated with the data of product (4).