X-ray structure of 5-[2-chlorophenyl]-10-[4-methylphenyl] 1,2,5,8,9,10 hexahydro 4,6[3H,6H] acridinedione and its interaction with calf thymus DNA by spectroscopic methods

The molecule [C26H24O2 NCl] mainly consists of a partially hydrogenated acridine ring system, with one phenyl and chlorophenyl substituent at the central pyridine ring. The cell parameters are; a = 10.715(1), b = 11.183(1), c = 9.267(2) Angstrom, alpha = 90.31(1), beta = 105.58(1) and gamma = 88.56(2)degrees. The central part of acridine ring adapts a boat conformation. Of the two outer 6-membered rings of the acridine moiety, one adopts a conformation intermediate between a sofa and a half-chair (ring I), while the other adopts a twist (ring III) conformation. The methyl substituted phenyl ring is equatorial and the chlorophenyl ring is axial with respect to the central pyridine ring. The acridine ring system is considerably folded along the bonds at the ring junctions. The chlorophenyl and phenyl rings are nearly parallel to each other. Packing of the molecules mainly involves van der Waals interactions. A preliminary DNA interaction study of this molecule has been carried out using spectroscopic methods. It shows evidence for the formation of a complex between dye and DNA. The results are interpreted in terms of its crystal structure.