SUBSTITUTED 3,4,12,12A-TETRAHYDRO-1H-[1,4]OXAZINO[3,4-C]PYRIDO[2,1-F][1,2,4]TRIAZINE-6,8-DIONE, PHARMACEUTICAL COMPOSITION, AND METHODS FOR PREPARING AND USING SAME

Influenza is an acute infectious respiratory disease caused by the influenza virus. It is part of the group of Acute Respiratory Viral Infections (ARVI). It occasionally spreads in the form of epidemics and pandemics. Currently, more than 2000 variants of the influenza virus differing in the antigen spectrum have been identified. Given that influenza is a serious threat to public health (worldwide, these annual epidemics lead to 3-5 million cases of severe illness, millions of hospitalizations, and up to 650,000 deaths), it seems appropriate to search for new anti-influenza drugs with improved characteristics.The inventors surprisingly found out that the previously unknown substituted 3,4,12,12a-tetrahydro-1 H-[1,4] oxazino[3,4-c]pyrido[2,1-f] [1,2,4]triazine-6,8-dione of general formula 1, its stereoisomer, their prodrug, pharmaceutically acceptable salt, solvate, hydrate, and a crystalline or polycrystalline form thereof are effective agents for prophylaxis and treatment of viral diseases, including influenzawhereR1 is (6,7-difluoro-5,10-dihydrothieno[3,2-c][2]benzothiepin-10-yl, (7,8-difluoro-4,9-dihydrothieno[2,23-c][2]benzothiepin-4-yl, (3,4-difluorophenyl)(phenyl)methyl, (3,4-difluorophenyl)(2-methylsulfanylphenyl)methyl, diphenylmethyl, bis(4-fluorophenyl)-methyl; R2 is hydrogen or a protective group selected from a series comprising (C1-C3 alkyl) oxycarbonyloxy, {[(C1-C3 alkyl)oxycarbonyl]-oxy}methoxy, {[2-(C1-C3 alkyl) oxyethoxy]carbonyl}oxy, ({[(1R)-2-[(C1-C3alkyl)oxy]-1-methylethoxy}carbonyl)oxy, {[(3S)-ethoxyfuran-3-yloxy]-carbonyl}oxy, [(ethoxy-2H-pyran-4-yloxy)carbonyl]oxy,{[(1-acetylazetidine)-3-yloxy]carbonyl}oxy, {[(C1-C3alkyl) oxycarbonyl] -oxy}methoxy, ({[2-(C1-C3 alkyl)oxyethoxy]carbonyl}oxy) methoxy.