Guanidopropionic acid

Fluorouracil is catabolized in an analogous manner to uracil, forming the following degradative products dihydrofluorouraci1, a-fluoro-6-ureidopropionic acid, a-fluoro-3-guanidopropionic acid, a-fluoro-3-alanine, urea, and CO2 (16). 

In the H-NMR study, it was found that in D2O the C-11 methylene protons in (1) easily exchange with deuterium atoms even at near neutral pH (37). In the deuterated compound (20), the signals for the C-10 methylene protons appear as a clear AB pattern (Table 2). Oxidation of the dideuterated compound (20) afforded oc-dideuterated guanidopropionic acid (17). 

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