The leaves of Beilschmiedia brevipes provided a new benzylisoquinoline alkaloid: (6,7-dimethoxy-4-methylisoquinolinyl)-(4'-methoxyphenyl)-methanone (1) and O,O-dimethylannocherin A (2), a new natural compound which has been synthesized before. Complete 1H- and 13C-NMR data of both compounds were reported. The structures were established through various spectroscopic methods notably 1D- and 2D-N...

Palladium-catalyzed hydroarylations and additional domino reactions of aza-bicyclic and tricyclic norbornene derivatives were investigated and a series of new epibatidine analogues were synthesized.

Pronuciferine N-oxide (1), a proaporphine N-methyl-N-oxide alkaloid, along with the parent alkaloid pronuciferine (2) were isolated from Berberis coletioides. The structure of the new compound was determined by spectroscopic evidence. Compound 1 is the first naturally occurring proaporphinoid alkaloid with an N-oxide functionality.

Isoquinoline alkaloids are a major group of pharmacologically important compounds. The universal precursor to the majority of this alkaloid class is (S)-reticuline. The biosynthesis of this important intermediate starting from the primary metabolite, Ltyrosine, has been completely solved at the enzyme level. One of the most diverse structures in the class of isoquinoline alkaloids are the benzo...

Convolvulaceae provide a rich source of tropane alkaloids, however, 2-substituted tropanes have been described for only few species of this taxon. In this note, 2,7-diesters such as ipvelutine [7β-acetoxy-2α-(tigloyloxy)tropane] isolated from the vegetative parts of the Australian Ipomoea velutina R. BR. are described as a new group of tropane diesters.

In recent years, a number of novel 3-alkyl pyridinium alkaloids were identified from the crude extract of the Arctic marine sponge Haliclona viscosa [1 – 5]. The material available from this sponge was limited by the small size of the individuals, their slow growth rate and the effort to sample substainably in the Arctic ecosystem. A new refinement of the spectroscopic methods led to improved r...