On January 4, 2022, Hu, Shuanghua; Lin, Zhaiwei; Cui, Baicheng published a patent.Name: Ethyl 3-fluoro-2-methylbenzoate The title of the patent was Preparation of pyridazinone derivatives and its application as anti-influenza drugs with CEN inhibitory effect. And the patent contained the following:
The present invention relates to the preparation of pyridazinone derivatives and its application as anti-influenza drugs with CEN inhibitory effect. In particular, the pyridazinone derivative I (wherein, R1 = H or, -C(=O)Y1, -C(=O)-O-Y1, etc.; Y1 = optionally substituted C1-10 alkyl, optionally substituted C3-8 cycloalkyl, optionally substituted aryl, etc.; where R* and R** = H or optionally substituted C1-6 alkyl; R2 and R3 = H, C1-6 alkyl, -C(O)-C1-6 alkyl, etc.; where R* and R** = H and optionally substituted C1-6 alkyl; q is 0-6; R4 = compound II; R9 and R10 = optionally substituted aryl, and optionally substituted heteroaryl; wherein the substituents are independent C1-6 alkyl, -C(O)- C1-6 alkyl, etc.; where R* and R** = H and optionally substituted C1-6 alkyl, and q is 0-6; R9 and R10 = linked to form the compound III; wherein n and m = 0-3, Q = CR*R**, NR*, O, S, SO, SO2; R* and R** = H and optionally substituted C1-6 alkyl;). Further, (R5 and R6 = H, or is selected from optionally substituted C1-8 alkyl, optionally substituted C2-8 alkenyl, etc.; wherein R* and R** = H and optionally substituted C1-6 alkyl, and q is 0-6; R7 and R8 = H, C1-6 alkyl, -C(O)- C1-6 alkyl, etc.; R* and R** = H and optionally substituted C1-6 alkyl; q is 0-6; R5, R7 or R6, R8 can be connected into a 5-8 membered saturated or unsaturated ring, such as a 6-membered ring, the ring may be a carbocyclic ring, or a heterocyclic ring containing O or N) or its pharmaceutically acceptable salts, solvates, hydrates, polycrystals, prodrugs, co-crystals, tautomers, stereoisomers, were prepared The inventive pyridazinone derivatives can be used as anti-influenza drugs with CEN inhibitory effect. The experimental process involved the reaction of Ethyl 3-fluoro-2-methylbenzoate(cas: 114312-57-1).Name: Ethyl 3-fluoro-2-methylbenzoate
The Article related to pyridazinone derivative preparation antiinfluenza drug cen inhibitor, Heterocyclic Compounds (More Than One Hetero Atom): Pyridazines, Cinnolines, and Phthalazines and other aspects.Name: Ethyl 3-fluoro-2-methylbenzoate
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