On April 8, 2021, Chen, Yi published a patent.Reference of 3,5-Dibromo-1-methylpyrazin-2(1H)-one The title of the patent was Preparation of heterocyclic compounds as inhibitors of Btk and mutants thereof. And the patent contained the following:
This invention relates to the title compounds I [Q0 = 5-9 membered aryl or heteroaryl; Q1 = 5-9 membered aryl or heteroaryl; Q2 = 5-7 membered heterocycloalkyl; Q3 = 5-membered heteroaryl; Q4 = 6-membered heteroaryl; W = C(O) or SO2; Z = NH or O; Warhead = C(R9):CHR8 or CCR10; each of R0, R1, R5-R10 = (independently) H, D, alkyl, etc.; R3 = H, halo, alkyl, haloalkyl, hydroxyalkyl; R4 = H, halo, alkyl; or R0 and R1 groups, taken together with the atom to which they are attached, may optionally form (un)substituted cycloalkyl or heterocycloalkyl; or two of R1 groups, taken together with the atom to which they are attached, may optionally form (un)substituted cycloalkyl or heterocycloalkyl; or two of R5 groups, taken together with the atom to which they are attached, may optionally form (un)substituted cycloalkyl, heterocycloalkyl, aryl, or heteroaryl; etc.; each of i, j, m, n = (independently) 0-4] or pharmaceutically acceptable salts thereof, useful for treating a neoplastic disease, autoimmune disease, and inflammatory disorder. E.g., a multi-step synthesis of N-(5-((6-(2-(7,7-dimethyl-1-oxo-1,3,4,6,7,8-hexahydro-2H-cyclopenta[4,5]pyrrolo[1,2-a]pyrazin-2-yl)-3-(hydroxymethyl)pyridin-4-yl)-4-methyl-3-oxo-3,4-dihydropyrazin-2-yl)amino)-2-(4-methylpiperazin-1-yl)phenyl)acrylamide, starting from 4-fluoro-3-nitroaniline and N-methylpiperazine, was described. Exemplified compounds I were tested for their Btk inhibitory activity (data given for representative compounds I). Pharmaceutical composition comprising compound I was disclosed. The experimental process involved the reaction of 3,5-Dibromo-1-methylpyrazin-2(1H)-one(cas: 87486-34-8).Reference of 3,5-Dibromo-1-methylpyrazin-2(1H)-one
The Article related to heterocyclic compound preparation btk inhibitor antitumor antiinflammatory autoimmune disease, Heterocyclic Compounds (More Than One Hetero Atom): Pyrazines and Quinoxalines (Including Piperazines) and other aspects.Reference of 3,5-Dibromo-1-methylpyrazin-2(1H)-one