Molecular conformation of N,N-dimethyl-4-amino-3-chloroangelicin C13H10O3NCl

The title compound was characterized by X-ray diffraction analysis. The crystals belong to the triclinic system, space group P1, with four molecules in the unit cell having a = 16.344(5), b = 10.343(3), c = 7.283(2) A, alpha = 109.1(1), beta = 90.2(1), gamma = 94.2(1), dc = 1.51 Mgm-3. The structure was determined from 1945 intensity data with I greater than or equal to 3 sigma (I) collected on a Philips PW 1100 diffractometer and refined by full matrix least-squares to the final R values R = 0.046 and Rw = 0.046. The molecular conformation is close to that of angelicin, the additional methyl groups being sandwiched with respect to the molecular plane, in order to minimize their steric hindrance. The possible intercalation of the title compound inside DNA has been considered.