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Studies have been conducted over the last decade to identify secondary metabolites from plants, in particular those from the class of alkaloids, for the development of new anti-Alzheimer's disease (AD) drugs. The genus Alseodaphne , comprising a wide range of alkaloids, is a promising source for the discovery of new cholinesterase inhibitors, the first-line treatment for AD. With regard to this, a phytochemical investigation of the dichloromethane extract of the bark of A. pendulifolia Gamb. was conducted. Repeated column chromatography and preparative thin-layer chromatography led to the isolation of a new bisbenzylisoquinoline alkaloid, N -methyl costaricine ( 1 ), together with costaricine ( 2 ), hernagine ( 3 ), N -methyl hernagine ( 4 ), corydine ( 5 ), and oxohernagine ( 6 ). Their structures were elucidated by the 1D- and 2D-NMR techniques and LCMS-IT-TOF analysis. Compounds 1 and 2 were more-potent BChE inhibitors than galantamine with IC 50 values of 3.51 ± 0.80 µM and 2.90 ± 0.56 µM, respectively. The Lineweaver-Burk plots of compounds 1 and 2 indicated they were mixed-mode inhibitors. Compounds 1 and 2 have the potential to be employed as lead compounds for the development of new drugs or medicinal supplements to treat AD.

The chemical composition of the essential oil from the leaves of Alseodaphne perakensis (Gamble) Kosterm (Lauraceae) growing in Perak, Malaysia was investigated for the first time. The essential oil was obtained by hydrodistillation and fully characterized by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). A total of 37 components (90.9 ± 2.5%) were successfully identified in the essential oil which were characterized by high proportions of bicyclogermacrene (15.8 ± 0.5%), δ-cadinene (11.7 ± 0.2%), γ-cadinene (6.3 ± 0.4%), and aromadendrene (5.6 ± 0.5%).

One new aporphine named tavoyanine A ( 1 ), along with four known aporphines laetanine ( 2 ), roemerine ( 3 ), laurolitsine ( 4 ), and boldine ( 5 ), and one morphinandienone type sebiferine ( 6 ) were isolated from the leaves of Phoebe tavoyana (Meissn.) Hook f. (Lauraceae). The isolation was achieved by chromatographic techniques, and the structural elucidation was performed via spectral methods. This paper also reports the antiplasmodial activity of roemerine ( 3 ), laurolitsine ( 4 ), boldine ( 5 ), and sebiferine ( 6 ). The results showed that 3 - 6 have a potent inhibitory activity against the growth of Plasmodium falciparum 3D7 clone, with IC 50 values of 0.89, 1.49, 1.65, and 2.76 µg/ml, respectively.

A phytochemical study of the bark of Alseodaphne perakensis has yielded three aporphine alkaloids: the new compound N-cyanomethylnorboldine (1), and the two known alkaloids N-methyllaurotetanine (2) and norboldine (3). The isolation was achieved by chromatographic techniques and the structural elucidation was performed via spectral methods, notably 1D- and 2D-NMR, UV, IR, and HRFABMS. The vasorelaxation activity of compound 1 has been studied.

Onenewalkaloid; (+)-N-(2-hydroxypropyl)lindcarpine (1),together with four known aporphine alkaloids, (+)-boldine (2) (+)-norboldine (3), (+)-lindcarpine (4) and (+)-methyllindcarpine (5) were isolated from the stem bark of Actinodaphne pruinosa Nees (Lauraceae). (+)-N-(2-Hydroxypropyl)lindcarpine (1) exhibited cytotoxic activity against P-388 murine leukemia cells with an IC(50 )value of 3.9 microg/mL. Structural elucidation of all the compounds were performed by spectral methods such as 1D- and 2D- NMR, IR, UV, and HRESIMS.

This study was designed to investigate the chemical constituents from Actinodaphne pruinosa growing in Malaysia. A phytochemical investigation of the leaves part resulted in the isolation of boldine (1), norboldine (2), laurotetanine (3), reticuline (4), syringaresinol (5), lupeol (6), and taraxerol (7). The structures of the isolated phytochemicals were established by analysis of their spectroscopic data, as well as the comparison with that of reported data. Notably, this is the first time to report the isolation and structural elucidation of the constituents from the leaves part of A. pruinosa. [ABSTRACT FROM AUTHOR]

A new aporphine alkaloid, demethoxyglauvine ( 1 ), along with seven known isoquinoline alkaloids, was isolated from the alkaloid crude extract of the leaves of Alseodaphne corneri . Their structures were determined by extensive spectroscopic analysis including 1D and 2D NMR ( 1 H– 1 H COSY, HSQC, and HMBC), mass spectrometry, and by comparing with the published data. A possible biogenetic pathway for the formation of 1 was proposed. [ABSTRACT FROM AUTHOR]