810715 min using 345-nm light from the Bausch and Lomb monochromator. Remeasurement of the luminescence spectra showed a decrease in the fluorescence intensity but no phosphorescence.The glass was allowed to thaw and was then refrozen. Use of the phosphoroscope now showed the phosphorescence spectrum of in ethanol. The intensity could not be measured since a clear glass could not be obtained.Photolysis of l a at 77°K. A solution of l a in ethanol was prepared and its fluorescence spectrum measured as described above.Use of the phosphoroscope showed no phosphorescence from the solution. The solution, maintained at 77"K, was irradiated for 2a.12Abstract: 1 -Norbornylamine, 1-apocamphylamine, and 1-adamantylamine have been deaminated using the nitroso-and nitroamide approach. The reaction yields carbonium ions that are reactive enough to abstract chloride ions from solvents such as methylene chloride, probably uia chloronium ion species. The norbornyl ions have a much higher reactivity than the 1-adamantyl ions as shown by the higher ratio of solvent attack to reaction with the negatively charged counterion. Oxygen-1 8 tracer experiments are also reported. The mechanism of deamination is discussed based on these and other results.

The biosynthesis of aristolochic acid-1 (1) was studied in Aristolochia sipho. Tyrosine, dopa, dopainine, and noradrenaline serve as specific precursors. The nitro group of aristolochic acid is derived from the amino group of tyrosine. The aristolochic acids are yet another group of natural products related to norlaudanosoline.

Efficient conversion of an O-methylnorbelladine into norpluviine in " Texas " daffodils has been observed. Feeding experiments with the [14C,3H] -labelled precursor have thrown light on the mechanism of norpluviine biosynthesis. The origin of the extra oxygen function in the related alkaloid, galanthine, is discussed. An isomer of O-methylnorbelladine has been synthesised and shown not to be a precursor for the major alkaloids of the " King Alfred " daffodil.IT is now well established1,2 that the diverse ring systems found amongst the Amaryllidaceae alkaloids can all be derived biologically by oxidative cyclisation of appropriate norbelladine (I; R = H) derivatives. For example, it has been shown l y 4 that the O-methylnorbelladine (I; R = Me) is a precursor of hzmanthamine (11) , the methoxyl group of the precursor providing the methylenedioxy function of the alkaloid, It seemed likely 2 9 5 that alkaloids of the lycorine (111; R,R = CH2, R' = H) group might also be derived from O-methylnorbelladine (I ; R = Me). The present Paper is concerned with the biosynthesis of two members of this group, norpluviine (IV; R = R' = H) and galanthine (111; R = R' = Me).

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