Two ethyl 3-acetamido-4-aryl-6-methyl-2-oxo-3,4-dihydropyran-5-carboxylates(3) were synthesized with high diastereoselectivities and characterized by IR,NMR and MS.The configuration of 3a was confirmed by single-crystal X-ray diffraction,ethyl 3-acetamido-4-(4-nitrophenyl)-6-methyl-2-oxo-3,4-dihydropyran-5-carboxylate(3a),C17H18N2O7.The crystal is of orthorhombic,space group Pbca with a = 11.7781(16),b = 9.5979(10),c = 32.115(3),V = 3630.4(7)3,Z = 8,Mr = 362.33,Dc = 1.326 Mg/m^3,λ = 0.71073,μ(MoKα) = 0.104 mm^-1,F(000) = 1520,the final R = 0.0646 and wR = 0.1464 for 1788 observed reflections with I 〉 2σ(I).The N-H and oxygen atom are involved in intermolecular hydrogen bonds which link the molecules into a one-dimensional chain and stabilize the structure.
N-[2-(4-chlorophenyl)-1-(1-methylcarbamoyl-2-phenyl-ethylcarbamoyl)-3-phenyl-cyclopropyl]benzamide,C33H30ClN3O3,has been synthesized and characterized by IR,1H NMR,13C NMR and single-crystal X-ray diffraction.The crystal is of triclinic,space group P1 with a = 11.646(2),b = 13.795(3),c = 14.559(3),α = 76.422(4),β = 78.028(4),γ = 74.500(4)°,V = 2164.6(7)3,Z = 3,Mr = 552.05,Dc = 1.270 g/cm3,λ = 0.71073 ,μ(MoKα)= 0.171 mm–1,F(000)= 870,the final R = 0.0469 and wR = 0.0805 for 5554 observed reflections with I 2σ(I).The N–H and oxygen atoms are involved in one-dimensional intermolecular hydrogen bonds,which further stabilize the structure.