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Bark of Tecoma arequipensis yielded the major alkaloidal component (-)-delta-N-normethylskytanthine whose structure was proven by X-ray diffraction analysis of the N-thiourea derivative. The stereochemistry of 1 at all four centers was enantiomeric with that of skytanthine previously reported from Tecoma stans and Skytanthus acutus. Gc-ms of the crude base fraction indicated the presence of several related alkaloids as very minor constituents.

Bei der Photolyse der Triacylhydroxylamine (Ia) bzw. (Ib) in Losungsmitteln wie Athanol und Cyclohexan entstehen unter Kohlendioxid-Abspaltung hauptsachlich die entsprechenden Imide (II) und (III).

Protopine and allocryptopine (in approximately equal amounts) make up over 95 per cent of the alkaloidal content of A. californica .

Thorough large scale investigations of Penstemon secundiflorus ssp. lavendulus and of P. grandiflorus resulted in the isolation of the new iridoid glucosides 5,6 β -dihydroxyadoxoside. The structure of 10-hydroxyepihastatoside has been revised to 10-hydroxyhastatoside using a chemical correlation. Also, the known iridoids (5 α H)-6-epidihydrocornin, cornin, hastatoside, 8-epihastatoside, β -dihydrohastatoside, penstemoside, (5 α H)-10-hydroxy-6-epidihydrocornin, 10-hydroxycornin and catalpol were isolated.

A new chromone was isolated from the bark of Zanthoxylum microcarpum and Z. valens and its structure determined by UV, IR, NMR and high resolution mass spectrometry as 5-hydroxy-7-methoxy-2-pentylchromone.

Subulacine N-oxide, a purportedly novel pyrrolizidine alkaloid from Heliotropium subulatum , was shown to have nmr and mass spectral properties identical with 1β,2β-epoxy-1α-hydroxymethyl-8α-pyrrolizidine, previously known from Crotalaria trifoliastrum .

Reaction of phenylnitromethane with acetic anhydride/sodium acetate at 80–85° produces N-benzoyl-N,O-diacetylhydroxylamine, which can be isolated in 30% yield. This compound was proposed previously as an intermediate in a similar reaction which had yielded only benzoic anhydride, triacetylhydroxylamine and acetanilide.

The isolation and structure determination of (2S,5S)-2,5-dibenzyl-1,4-dimethylpiperazine ( 1 ), a new alkaloid biogenetically related to L-phenylalanine diketopiperazine, is described.

The structure of the alkaloid buddamin, isolated from Buddleya davidii cannot be correct, based upon the reported spectral data. An alternate structure is proposed, which also suggests that buddamin is an artifact of the isolation procedure.

Argemone fruticosa Thurber ex Gray was analyzed and found to contain hunnemanine as the major alkaloid along with allocryptopine. A. echinata G. B. Ownb. was found to contain cryptopine and berberine as major alkaloids. These analyses indicate that these two species belong among the more specialized species of the genus.

COMPARATIVE rates of incorporation of carbon dioxide labelled with carbon-14 led to the proposal1 that, in Papaver somniferum, thebaine is the first octahydrophenanthrene alkaloid formed, and is converted by successive O-demethylations to codeine and finally to morphine. Although this sequence seemed best to explain the labelling ratio among these three alkaloids, conclusive proof was lacking. The results described here, considered with the previous data1, constitute proof of this interrelationship.