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Phytochemical components of the aerial parts of Andrographis paniculatacollected in Bac Giang province was investigated. Fourteen compounds, including seven labdane diterpene lactones [andrographolide (1), 3,19‐isopropylidene‐andrographolide (2), andropanolide (4), 14‐deoxy‐12‐hydroxyandrographolide (5), 14‐dehydroxyandrographolide‐12‐sulfonic acid (6), 14‐deoxy‐11,12‐didehydroandrographolide (8), 14‐deoxy‐14,15‐didehydroandrographolide (11)], together with four diterpene glycosides [andrographiside (3), neoandrographolide (7), andropanoside (9), 14‐deoxy‐11,12‐didehydroandrographiside (10)], and three iridoid glycosides [harpagide (12), 6‐epi‐8‐O‐acetyl‐harpagide (13), procumbide (14)] were isolated. Among these, 14‐dehydroxyandrographolide‐12‐sulfonic acid (6) was isolated for the first time from natural resource, and for the first‐time harpagide (12)was isolated from Andrographis paniculataspecies. The detailed structures of isolated compounds were elucidated by analyses of 1D and 2D NMR spectra and compared to the published data. Diterpene lactones, 1–2, 5and 10–11, were evaluated for their anti‐inflammatory inhibition on LPS‐triggered inflammatory responses in RAW 264.7 cells, in which 1and 2showed significantly potent inhibition on NO production with IC50values of 1.3 and 0.34 µm, respectively.

Nine compounds, including two sesquiterpenes [((+)‐spathulenol (1), caryophyllenol‐II (2)], five flavonol glycosides [rutin (3), quercitrin (4), rhamnocitrin 3‐rutinoside (5), oxytroflavoside G (6), curcucomoside D (7)], and two hydrocarbons [2‐phyten‐1‐yl‐caprylate (8) and tritriacontan‐1‐ol (9)] were reported for the first time from the leaves and twigs of Magnolia coriacea. Their detailed structures were confirmed by 1D and 2D NMR spectra analyses and compared to the published data.

Sulfonylureas derivatives were demonstrated to be effective inhibitors towards α‐glucosidase, thus also expected possessing inhibitory potentiality towards tyrosine phosphatase structure 1B. Five new sulfonylureas derivatives (S1‐S5), exhibiting α‐glucosidase inhibition activity, were selected for in silicoscreening for inhibitability towards UniProtKB‐PTP1B structure. Density functional theory confirms their existence; natural bond orbital analysis infers their stability; electronic transferability suggests their capability regarding intermolecular interaction. Docking‐based investigation interprets the inhibitory potentiality of the compounds into the order of complexes: S3‐PTP1B> S4‐PTP1B> S1‐PTP1B> S5‐PTP1B> S2‐PTP1B. QSARS‐based analysis specifies S4as the most physicochemically and pharmaceutically compatible candidate for the general application as a protein inhibitor (Molecular mass: 213.9 amu; Dispersion coefficient: LogP 4.01; DSaverage: 11.9 kcal.mol‐1). The computer‐based findings encourage further confirmation from experiment‐based researches and development for a versatile inhibitor towards diabetes‐related protein structures (aka. α‐glucosidase and tyrosine phosphatase structure 1B).

From the leaves and barks of Dolichandrone spathaceacollected in the mangrove forest of Hue province, three iridoids {6‐O‐[(E)‐4‐methoxy cinnamoyl]catalpol (1), 6‐O‐[(E)‐3,4‐dimethoxy cinnamoyl]catalpol (2), nemoroside (3)} and three ursane‐type triterpenoids [ursolic acid (4), pomolic acid (5), uncaric acid (6)] were isolated and structurally elucidated. Besides, succrose octaacetate (7), daucosterol tetraacetate (8) and 1‐hentriacontanol (9) were identified from the fruits of this mangrove species. It is the first time compounds 6, 7, 9were isolated from Dolichandrone spathacea. The main constituents of this plant, iridoids 1and 2, were tested for the inhibition of IL‐6, TNF‐α factors and NO production. The anti‐inflammatory activity as well as the phytochemistry of the fruits of this species are reported for the first time.

Eight sesquiterpenoids including costunolide (1), parthenolide (2), 11α,13‐dihydroparthenolide (3), 9β‐hydroxy‐dihydroparthenolide (4), (‐)‐bisparthenolidine (5), 11α,13‐dihydro‐β‐cyclocostunolide (6), α‐cadinol (7), magnograndiolide (8)were isolated from the barks and roots of Michelia alba. The structures of these compounds were elucidated by spectroscopic methods (MS, 1D and 2D NMR) and comparison with the reported data. Compounds 5‐8have been isolated for the first time from Michelia alba.

From the leaves of Magnolia insignis, six compounds including (+)‐afzelechin (1), budlein B (2), pinoresinol monomethyl ether‐β‐D‐glucoside (3), nicotiflorin (4), kaempferol‐3‐O‐β‐D‐xylopyranose (5), astragalin (6)were isolated. The structures of these compounds were elucidated by MS and NMR spectra and comparison with the reported data. This is the first time that all of the above compounds have been isolated from Magnolia insignis.

Centella asiaticais a very popular plant in Vietnam and in other South and Southeast Asia. It grows wildly or planted in all parts of Vietnam. People use this plant for treatment of many diseases or as a vegetable. This plant is a main product of economic importance in Quang Tho village, Quang Dien district, Thua Thien – Hue province, where it is planted according to VIETGAP standard. The MeOH extract from the aerial parts of Centella asiaticacollected from Quang Tho village has shown a good inhibition of acetylcholinesterase in an experiment on mice brain. Chromatographic separation of this extract yielded kaempferol, asiatic acid, madecassic acid, asiaticoside and a large amount (2.28 % of dry material) of asiaticoside A and asiaticoside B as a mixture with a ratio of 35:65, determined by 1H NMR spectrum.