Edward Leete

5-Oxo-octanoic acid and 5-oxo-octanal, precursors of coniine

The administration of [6-14C]-5-oxo-octanoic acid or [6-14C]-5-oxo-octanal to hemlock plants (Conium maculatum) resulted in the formation of [1′-14C]coniine, with high incorporations of activity as compared with [1-14C]acetate and [1-14C]octanoic acid, suggesting that they are the immediate precursors of coniine.

Biosynthesis of dioscorine

The administration of [1-14C]acetate to Dioscorea hispida plants resulted in the formation of radioactive dioscorine (0·2% incorporation), the pattern of labelling being consistent with the hypothesis that this alkaloid is formed from four acetate units and a piperidine moiety which may be derived from lysine.

Lead tetra-acetate oxidation of NN-dimethylglycine and its relevance to the biosynthesis of the pyrrolidine ring of nicotine

A degradative sequence which has been used to determine the distribution of radioactivity in the pyrrolidine of nicotine involves, as one of the steps, the oxidation of NN-dimethylglycine with lead tetra-acetate; the formaldehyde produced in this reaction, formerly thought to originate entirely from C-2, has been shown to be derived in appreciable amounts from the N-methyl groups.