Reactive intermediates – (thio)phosphoryl monochlorides bearing a nitroxyl moiety were synthesized from
either 4-amino-2,2,6,6-tetramethylpiperidine-1-oxyl or 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl, and (thio)phosphoryl
dichlorides in the presence of triethylamine, DMAP or DABCO in 26-62% yield. Synthesized (thio)phosphoryl
monochlorides were condensed with potassium salt of 3-chloro-7-hydroxy-4-methylcoumarin affording phosphorylated
coumarin derivatives bearing a nitroxyl moiety in 57-92% yield. Antifungal activity of synthesized nitroxyl derivatives of
coumarin was found.