Abstract Two isoflavone derivatives, 5, 6, 7, 4′-tetramethoxyisoflavone (I) and 6, 4′- dimethoxy-7-ethoxy-5-hydroxylisoflavone (II), have been synthesized and their crystal structures were determined by 1 H NMR and single crystal X-ray diffraction studies. I is triclinic, space group P-1 with a= 7.828 (1) Å, b= 10.285 (2) Å, c= 11.608 (2) Å, α= 104.90 (2)°, β= 110.546 (9)°, γ= 99.54 (1)° and Z= 2. II is orthorhombic, space group Pna2 1 with a ...
