METHOD FOR SYNTHESISING DISODIUM SALT OF DEXAMETHASONE 21-PHOSPHATE APPLIED FOR TREATING PATIENTS WITH CORONAVIRUS INFECTION (COVID-19) Russian patent published in 2022 - IPC C07J5/00 

FIELD: chemistry.

SUBSTANCE: present invention relates to a method for synthesising disodium salt of dexamethasone (11,17βα-dihydroxy-9α-fluoro-16α-methyl-21-(phosphonooxy)pregna-1,4-diene-3,20-dione) 21-phosphate by the formula (I) - a corticosteroid medicinal product exhibiting a desensitising, antishock, immunosuppressive, antiallergic, anti-inflammatory effect. The compound by the formula I is produced from dexamethasone (11β,17α,21-trihydroxy-9α-fluoro-16α-methylpregna-1,4-diene-3,20-dione) by the formula (II) by means of a reaction with pyrophosphoryl chloride taken at the rate of no less than 1.0 mol per 1.0 mol of the compound II, in the environment of a cyclic ether, followed by hydrolysis of the resulting 21-phosphate dexamethasone dichloro-derivative, removal of steroid impurities from the aqueous medium by the method of liquid-phase extraction using chlorinated hydrocarbon, extraction of the formed dexamethasone (11β,17α-dihydroxy-9α-fluoro-16α-methyl-21-(phosphonooxy)pregna-1,4-diene-3,20-dione) 21-phosphate by the formula (III) from the aqueous medium by the method of solid-phase extraction at room temperature using non-ionogenic polymers selected from Macronet MN-200, Macronet MN-202, AmberLite XAD-4, AmberLite XAD-16, desorption thereof by a mixture of chlorinated hydrocarbon and aliphatic alcohol, and processing of 21-phosphate dexamethasone with sodium alcoholate in the environment of the corresponding aliphatic alcohol, wherein no less than 1.94 moles of sodium alcoholate is taken per 1 mol of the compound III.

EFFECT: proposed method provides a possibility of synthesising a target product of the appropriate quality while ensuring a molar yield of at least 90%.

10 cl, 3 ex