11-Cyclopropyl-6-methyl-6,11-dihydro-5H-pyridazino[3,4-e]pyrido[3,2-b][1,4]diazepin-5-one AIDS-072936 AIDS072936 Azanevirapine derivative Pyridazino[3,4-e]pyrido[3,2-b][1,4]diazepin-5-one