An efficient one-pot four-component condensation reaction of acenaphthoquinone, pyrazolones or barbituric acid and 1,1-bis(methylthio)-2-nitroethene and alkylamines in ethanol for the synthesis of novel spiro[acenaphthylene-1,4′-pyrano[2,3-c]pyrazol]-2-one and spiro[acenaphthylene-1,5′-pyrano[2,3-d]pyrimidine]-trione is descibed. The significant features of this method include, readily available starting materials, operational simplicity, green solvent, catalyst-free condition, no column chromatographic purification and good to high yields.