3-(2,3,5,6,7,8-Hexahydro-1H-cyclopenta[b]quinolin-9-yl)-1,5-bis(4-methoxyphenyl)biuret

Abstract

Ipidacrine (2,3,5,6,7,8-hexahydro-1H-cyclopenta[b]quinolin-9-amine) was reacted with 4-methoxyphenyl isocyanate to give the title compound, C28H30N4O4. An intramolecular N—H...O hydrogen bond results in an essentially planar [r.m.s. deviation from the mean plane is 0.126 (1) Å] conformation for the biuret unit. The central ring of the quinoline unit is twisted by 78.2 (1)° with respect to the biuret mean plane, whereas the two 4-methoxybenzene rings are twisted out of this plane by 24.3 (1)° and 48.5 (1)°, resulting in an overall propeller-like structure. An intermolecular N—H...N hydrogen bond between the biuret NH atom and the quinoline ring nitrogen defines the crystal packing.