METHOD OF OBTAINING CARBAMIDE LABELLED BY STABLE ISOTOPE C Russian patent published in 2012 - IPC A61K49/06 C07C273/04 C07C275/06 C07B59/00 

FIELD: medicine, pharmaceutics.

SUBSTANCE: invention relates to method of obtaining carbamide with stable carbon isotope ¹³C for application in medical diagnostics of gastrointestinal tract diseases. Claimed method has two stages, the first stage includes interaction of labeled carbon dioxide and propylene oxide at temperature 120-130°C and pressure 1.3-1.5 MPa in presence of catalyst with further isolation of labeled propylene carbonate. Catalyst of the first stage is complex of zinc bromide with tertiary organophosphine or 1-butyl-3-methylimidasolium chloride, and mole ratio of propylene oxide to catalyst constitutes 500-2000:1. At the second stage carried out is ammonolysis of isolated liquid propylene carbonate at temperature 130-150°C and pressure 5.0-7.0 MPa with further isolation of target product.

EFFECT: method ensures obtaining carbamide, labeled by stable isotope ¹³C, with high output with sufficient simplicity and manufacturability of method and absence of highly toxic and explosive substances.

4 cl, 2 tbl, 14 ex