FIELD: chemistry.
SUBSTANCE: invention relates to a method of manufacture of an antiviral compound (A) of a general formula (I) or a pharmaceutically acceptable salt thereof, wherein R1 is selected from an alkyl group with 1 to 4 carbon atoms, and manufacture includes the following stages: stage 1 - diazotization of a compound (B) of a general formula (II), wherein R2 is selected from hydrogen in presence whereof the compound (B) is dissolved in nitric acid, cooled to -7°C, and sodium nitrate is added, resulting in synthesis of a diazonium compound of a general formula (III) or a pharmaceutically acceptable salt thereof; stage 2 - condensation reaction of a diazonium compound of a general formula (III) or a pharmaceutically acceptable salt thereof obtained on stage 1 with an α-nitroether of a general formula (IV), wherein r3 is selected from -C(O)-OR5, where R5 is an alkyl group with a number of nitrogen atoms between 1 and 4, R4 is an alkyl group with a number of carbon atoms between 1 and 4, in a cooled sodium hydroxide solution at the ph of the reaction mixture of 9 to 10, stirring and at the temperature of 0°C for 1 hour and then at room temperature for 2 hours; stage 3 - alkylation of the compound obtained on stage 2 or a pharmaceutically acceptable salt thereof with an alkylating agent of the formula (V): R1-X, wherein R1 is an alkyl group with a number of carbon atoms between 1 and 4, X is a halogen atom, at room temperature, stirring to produce an antiviral compound (A) of a general formula (I) or a pharmaceutically acceptable salt thereof. Invention also relates to another method of an antiviral compound (A) of a general formula (I) and a method of manufacture of a compound (B) of a general formula (IIR1).
EFFECT: developed one-stage method of manufacture of an antiviral compound (A) of a general formula (I) or a pharmaceutically acceptable salt thereof without extracting byproducts, which allows to raise the output of the target product.
7 cl, 3 ex
