6-Bromo-2-chloro-8-cyclopentyl-5-methylpyrido[2,3-d]pyrimidin-7-one; 6-Bromo-2-chloro-8-cyclopentyl-5-methylpyrido-[2,3-d]pyrimidin-7(8H)-one; 6-bromo-2-chloro-8-cyclopentyl-5-methylpyrido[2,3-d]pyrimidin-7-one