Alkaloids of the Australian Rutaceae: Acronychia baueri. III.The Structure of Acronycine

Abstract

Oxidative degradations of acronycine with nitric acid and ozone have been studied. Hot concentrated nitric acid converts noracronycine and nordihydroacronycine into l-methyl-4-quinolone-3-carboxylic acid while nitric acid on acronycine under the same conditions yields first trinitroacronycine and finally 6.nitro-l-methyl-4-quinolone- 3-carboxylic acid. Ozonolysis of acronycine gives a phenolic aldehyde, C16H13O4N, which has been deduced to be 1- or 3-formyl-2-hydroxy-4-methoxy-10-methylacridone (V or VII). These data together with information supplied in Part II indicate acronycine to be either 4-methoxy-2',2',l0-trimethyl-α-pyrano-(5',6'-1,2)acrid-5-one (IV) or 4-methoxy-2',2',10-trimethyl-α-pyrano.(5',6'-3,2)acrid-5-one (VI).