6-OXO-1-PHENYL-2-(PHENYLAMINO)-1,6-DIHYDROPYRIMIDINE-4-OLATE OF SODIUM AND METHOD FOR PREPARATION THEREOF Russian patent published in 2018 - IPC C07D239/54 A61P27/00 A61P9/12 

FIELD: chemistry.

SUBSTANCE: invention relates to a novel water-soluble compound of formula I, 6-oxo-1-phenyl-2-(phenylamino)-1,6-dihydropyrimidine-4-olate of sodium, which can be used as a neurorehabilitation medication for head injury.

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Invention also relates to a process for the preparation of a compound of formula I. Method is that 1,3-diphenylguanidine is reacted with malonic ether in a molar ratio of 2:1 at a temperature of 145–155 °C followed by cooling to 20–25 °C, adding sodium hydroxide solution to the reaction products and isolating the desired product from the liquid fraction. Reaction of 1,3-diphenylguanidine with malonic ether can be carried out in a medium of a high boiling aprotic solvent (o-xylene). To isolate the desired product, the liquid fraction is filtered off, the filtrate is acidified to pH 3–4 with hydrochloric acid, the precipitate formed is separated and converted to a solution with sodium hydroxide, and the solid desired product is obtained by evaporating the solution at a temperature of 35–40 °C.

EFFECT: in contrast to the closest analogue, the method makes it possible to obtain a water-soluble compound without the use of fire-explosion-proof starting compounds and process conditions with an 85–88 % yield.

4 cl, 2 tbl, 3 ex