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The rare alkaloid telobine (3) has been isolated from the bark of the new Daphnandra sp., D. apatela Schodde, together with five new alkaloids. The structures of three of these, apateline (1), 1,2- dehydroapateline (6) and 1,2-dehydrotelobine (5), have been determined.

Ceric ammonium nitrate cleaved laudanosine (1) quantitatively into veratraldehyde (2) and 6,7-dimethoxy-2-methyl-3,4-dihydroisoquinolinium ion (3), isolated as the reduced product, 6,7-di-methoxy-2-methyl- 1,2,3,4-tetrahydroisoquinoline (4). The reagent also degraded tetrandrine (5), hernandezine (6) and O-methylmicranthine (7) in a similar way; the products after reduction were isolated as diamines [(8), (9) and (10) respectively] and a diol, 3-[4?- (hydroxymethyl)phenyloxy]-4-methoxybenzyl alcohol (II), in nearly quantitative yields. When applied to berbamine (12), thalibrunine (13) and tenuipine (14), this reaction gave good yields of the nitrogen- containing fragments only.

The characterization of a new benzylisoquinoline alkaloid, isosevanine, C18H15NO4, m.p. 148° isolated from Hedycarya angustifolia, by a single- crystal X-ray diffraction study is described. Crystals are monoclinic, P21/n, a 22.45(1), b 5.746(4), c 11.569(3) Ǻ, β 93.65(4)°, Z = 4; the structure was refined to a residual of 0.053 for 1016 independent 'observed' reflections.

The crystal structure of the alkaloid aristoserratine,* C20H24N2O, has been determined by single-crystal X-ray diffraction methods at 295 K, the structure being refined to a residual of 0.034 for 1107 independent 'observed' reflections. Crystals are monoclinic, P21, a 14.836(5), b 8.568(3), c 6.633(3) , β 98.05(3), Z 2. The relative configuration is established and, by inference, by comparison of the circular dichroism spectrum with that of aristoteline, the absolute configuration is assigned.

Darlingia ferruginea J. F. Bailey contains the new tropane alkaloids ferrugine (2) and 3α-benzoyloxy-2α-hydroxybenzyltropane (4) as well as darlingine (1) and ferruginine (3), which also occur in D. darlingiana.

The structures of eleven alkaloids isolated from Darlingia darlingiana (F. Muell.) L. A. S. Johnson, a Queensland proteaceous tree, have been determined. They comprise a tropene, two pyranotropanes, and eight pyrrolidine alkaloids.

Fourteen alkaloids have been isolated from Bellendena montana, a monotypic proteaceous plant endemic in Tasmania. The structures of ten of these, bellendine (1), isobellendine (2), darlingine (3),5,ll-dihydroisobellendine (5), 2,3-dihydrobellendine (6), 2,3-epidihydrobellendine (7), 2,3-dihydrodarlingine(8), 3α-acetoxy-6β-isobutoxytropane (9), 6β-acetoxy-3α-isobutoxytropane (10) and 3α-acetoxy-6β-hydroxytropane (11), have been established.

Three new biscocla urine alkaloids, johnsonine (1), N-methylapateline (12) and N-methylnorapateline (13), have been isolated from the recently described species D. johnsonii. This rare plant also contains the alkaloids repandinine (a), O-methylrepandine (3), nortenuipine (6) and repandine (2), previously isolated from other Daphnandra spp.

The known alkaloids (-)-antofine (1), dehydroantofine (5),(-)-cryptowoline (6), (4- cryptowolidine (7), and (-)-cryptowolinol (8), were isolated from the New Caledonian lauraceous plant Cryptocarya phyllosternon, together with five new bases: two secophenanthro-indolizidines, (-)-phyllostemine (2) and (-)-phyllosteminine (3), one pyrrolidinylacetophenone, (-)-phyllostone (4), and two quaternary tetrahydrobenzylisoquinolines, (+)-phyllocryptine (9) and (+)-phyllocryptonine (10). Chemical and spectroscopic methods were used for identification and structural investigation. A synthesis of phyllocryptonine has permitted its stereostructure to be determined.

The isolation and structural determination of the new alkaloid dielsine (3), which belongs to the small group of repanduline-type bases, are described.

The major alkaloids of Anthocercis tasmanica are shown to be hyoscine and nicotine.

The original source of tasmanone appears to have been Eucalyptus tasmanica rather than E. risdoni or E. linearis. A far richer source has been found in E. camfieldii. Tasmanone has been shown to be a tautomeric mixture of enols (IV) and (V). The major isomer forms approximately 70% of the mixture.

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Of the new non-phenolic alkaloids previously reported in the bark of Atherosperma moschatum Labill., atherospermidine has been shown to have the methoxylspermatheridine structure (II), while atherosperminine (VIII) and a further new base, methoxyatherosperminine (IX), have proved to be members of the small group of phenanthrene alkaloids.

From a nuclear magnetic resonance study of the tautomerism of tasmanone and 1,1,3,3-tetramethylphloroglucinol (syncarpic acid), it is deduced that tasmanone consists of a mixture of tautomers (I) and (II) with the tautomer (I) present in the larger proportion. Similarly it is deduced that the tautomers of agglomerone (XI; R = CHMe2), 3-acetyl-O-methylfilicinic acid (XI R; = Me), ceroptene (XI; R = CH=CHPh), and usnic acid (XIII) with the extended conjugation are the more stable and populated ones.

The bark of Atherosperma moschatum Labill. of the family Monimiaceae contains the known bisbenzylisoquinoline alkaloids berbamine (1.6 per cent.) and isotetrandrine (0.06 per cent.), together with isocorydine (0.007 per cent.) and three new alkaloids atherosperminine, C20H23O2N (0.005 per cent.), atherospermidine, C18Hl3O4N (0 006 per cent.), and spermatheridine, C17H11O3N (0.002 per cent.). The last two alkaloids are bright yellow and weakly basic. In addition to the bases listed above the leaves contain a trace of another alkaloid spermatherine. Both bark and leaves contain . phenolic alkaloids which were not further investigated. The position of the hitherto unlocated hydroxyl group in berbamine is unequivocally established by fission of O-ethylberbamine with sodium in liquid ammonia.

The isolation and structural determination of haemodorin, a new phenalenone pigment obtained from Haemodorum distichophyllum (Hook.) (Haemodoraceae), is described.

Bark of the New Caledonian monimiaceous plant Nemuaron vieillardii contains the alkaloids laurotetanine, N-methyllaurotetanine, norisocorydine, atheroline, O-methylflavinantine, and a new bisbenzylisoquinoline alkaloid nemuarine, which is the major alkaloid of the leaves. Nemuarine is shown to have a novel structure with a 5-6? ether link between the isoquinoline residues.

The mass spectra of a series of alkaloids of the spermatheridine group, together with those of their alkoxy derivatives, are reported and discussed. The characteristic fragmentation processes, substantiated by appropriate metastable peaks, exact mass measurements, and in some cases by deuterium labelling, facilitate the location of substituents in the tetracyclic system. A structure for moschatoline is deduced from a consideration of the mass spectra of its derivatives.