(±)-Pheharmines A-B, two pairs of racemic alkaloids with a morpholino[4,3,2-]β-carboline core, from the roots of .

Two pairs of unprecedented β-carboline-phenylpropanoid heterogeneous alkaloids, (±)-pheharmines A-B (1-4), characterized by a morpholino[4,3,2-]β-carboline core with two chiral centers, were isolated from the roots of . The structures, including their absolute configurations, were identified using spectroscopic analyses and electronic circular dichroism (ECD) calculations. The biosynthetic hypothesis for the formation of pheharmines A-B was proposed.

Anti-tumor alkaloids from Peganum harmala.

Six alkaloids peharmalines F-K, along with 14 known ones, were isolated from the aerial part of Peganum harmala L.. The structures of the isolated compounds were determined based on their HR-ESI-MS data, extensive NMR spectroscopic analyses, and ECD calculations.

Pegaharmols A-B, Axially Chiral β-Carboline-quinazoline Dimers from the Roots of .

Two nonbiaryl axially chiral β-carboline-quinazoline dimers, pegaharmols A () and B (), were isolated from the roots of . Their planar structures were elucidated by the spectroscopic methods of high-resolution mass spectrometry and 1D and 2D nuclear magnetic resonance (NMR). The stereochemistry was established by a comparison between the experimental data of NMR and electronic circular dichroism and the computed data by quantum mechanical calculations.

Bioassay- and Chemistry-Guided Isolation of Scalemic Caged Prenylxanthones from the Leaves of Garcinia bracteata.

With bioassay- and chemistry-guided fractionation, seven new caged prenylxanthones including two scalemic mixtures, epiisobractatin (1), 13-hydroxyisobractatin (2), 13-hydroxyepiisobractatin (3), 8-methoxy-8,8a-dihydrobractatin (4), 8-ethoxy-8,8a-dihydrobractatin (5), garcibracteatone (6), and 8-methoxy-8,8a-dihydroneobractiatin (7), and the eight known compounds 8-15 were isolated from the leaves of Garcinia bracteata. The structures were unambiguously elucidated through analysis of spectroscopic data. The 2D structures and relative configurations of 1 and 5 were confirmed by X-ray crystallographic analysis.

Racemic indole alkaloids from the seeds of Peganum harmala.

Five pairs of new 2-oxoindole alkaloids, (±)-peganumalines A-E (1-5), and a new indole alkaloid, peganumaline F (6), along with two known analogues, were isolated from the seeds of Peganum harmala. Their structures and absolute configurations were elucidated through spectroscopic analyses and quantum chemistry calculations. Notably, (±)-peganumalines A (1) represent a pair of rare 2-oxoindole dimeric alkaloid enantiomer with the hitherto unknown carbon skeleton.

Cytotoxic quinazoline alkaloids from the seeds of Peganum harmala.

Seventeen quinazoline alkaloids and derivatives, containing two pairs of new epimers, named as (S)- and (R)-1-(2-aminobenzyl)-3-hydroxypyrrolidin-2-one β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranoside (1, 2), (S)- and (R)-vasicinone β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranoside (3, 4), and a new enantiomer (12b), together with six known ones (5-8, 10, and 12a), and three pairs of known enantiomers (9, 11, and 13), were isolated from the ethanol extracts of the seeds of Peganum harmala L.. Their structures including the absolute configuration were elucidated by using 1D and 2D NMR, and ECD calculation approaches.

A new biflavonoid and a new triterpene from the leaves of Garcinia paucinervis and their biological activities.

A new biflavonoid, paucinervin K (1) and a new triterpene, 23-hydroxy-friedelin (2), together with eleven known compounds 3-13 were isolated from the leaves of Garcinia paucinervis. Their structures, including stereochemistry, were determined by spectroscopic analysis of NMR, MS, IR and ECD calculation and the octant rule. Some of the isolated compounds were tested for antiproliferative, α-glucosidase inhibitory and antioxidant activities in vitro.

Bioactive terpenoids from Silybum marianum and their suppression on NO release in LPS-induced BV-2 cells and interaction with iNOS.

Three new (1-3) and one known (4) bioactive terpenoids were isolated from the seeds of Silybum marianum based on the investigation to get new NO inhibitors. Their structures were determined by extensive NMR (1D and 2D NMR) and MS spectroscopic data, and the absolute configurations were identified by experimental and calculated ECD spectra. The NO inhibitory activities in murine microglial BV-2 cells and interactions with iNOS protein by molecular docking were evaluated for all compounds.

Lignans and triterpenoids from Vitex negundo var. heterophylla and their biological evaluation.

Three new phenylnaphthalene-type lignans, vitexnegheteroins E-G (1-3), and a new polyoxygenated ursane-type triterpene, vitexnegheteroin H (9), were isolated from the seeds of Vitex negundo var. heterophylla, together with ten known compounds. Their structures were established on the basis of extensive 1D and 2D NMR experiments, as well as their mass spectroscopic data.