摘要:
The behavior of 1-R-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acid pyridinylmethylene-hydrazides under bromination conditions using molecular bromine has been studied. It has been found that the 1-N-allyl derivative is characteristically halocyclized to the corresponding oxazolo[3,2-a]quinoline, whereas the 1-N-hexyl-substituted acylhydrazone is unexpectedly brominated in the azomethine fragment.