Synthesis and Pharmacological Activity of 1-Hydroxy-, 1-Amino-, and 1-Hydrazino-Substituted 2,3-Dihydro-1H-pyrazolo[1,2-a]pyridazine-5,8-diones and 2,3-Dihydro-1H-pyrazolo[1,2-b]phthalazine-5,10-diones