Abstract

In ethyl 5-cyano-2,6-dimethyl-4-(5-nitro-2-furyl)-1,4-dihydropyridine-3-carboxylate, C 15H 15N 3O 5, the molecules are linked into chains by a single N - H⋯O hydrogen bond. The molecules in diethyl 2,6-dimethyl-4-(5-nitro-2-furyl)-1,4-dihydropyridine-3,5-dicarboxylate, C 17H 20N 2O 7, are linked by a combination of one N - H⋯O hydrogen bond and two C - H⋯O hydrogen bonds into sheets built from equal numbers of R 2 2(17) and R 4 4(18) rings. In 2,6-dimethyl-4-(5-nitro-2-furyl)-1,4-dihydropyridine-3,5-dicarbonitrile, C 13H 10N 4O 3, the molecules are linked by a combination of a three-centre N - H⋯(O) 2 hydrogen bond and two independent two-centre C - H⋯O hydrogen bonds into complex sheets containing four types of ring. © 2006 International Union of Crystallography.