C15H15N03,Mr=257·28, rhombohedral, R≈3,a=40·510(4),c=4·5456(3)Å,V=6460(2)Å,Z=18,dc=1·1905(3)g/cm3, CuKα(λ=1·5418Å), μ= 6·5cm−1,F(000)=2448,T=295K, finalR(F)=0·091,wR=0·141 for 1425 significant reflections,I≤2·5 σ(I). The molecules are stacked along thec axis and are stabilized in the unit cell by N−…O and C−H…O types of hydrogen bonds. Centrosymmetrically related molecules form dimers about the centre of inversion, and the hydrogen bond pattern is reminiscent of pyrimidine-purine base pairing in nucleotides.
