Paliperidone Related Compound D (20 mg) (3-{2-[4-(6-Fluoro-1,2-benzisoxazol-3-yl) piperidin-1-yl]ethyl}-9-hydroxy-2-methyl-6,7,8,9-tetrahydro-4H-pyrido[1,2-a]pyrimidin-4-one N-oxide)