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Objective/Background The Hypericum hookerianum is widely distributed in Asian countries and prevalently used in traditional herbal medicines for its significant antioxidant, antipyretic, and anticancer properties. To date, very limited reports are available regarding the phytochemical profile, and there are no reports that have studied the neuroprotective potentials of this plant. Experimental Methods The aerial parts of H. hookerianum were collected from the Sapa mountainous district, Lao Cai province of Vietnam. The extracts were prepared using methanol, n-butanol, ethyl acetate, and chloroform and fractionated by normal-phase silica gel column chromatography to isolate compounds. The purity of the isolated compounds was analyzed by liquid chromatography combined with mass spectrometry. The structures were studied using nuclear magnetic resonance spectroscopy. All the isolates were evaluated for their neuroprotective activity against the neurotoxicity induced by glutamate in HT-22 hippocampal cells and 6-hydroxydopamine (6-OHDA) in SH-SY5Y neuroblastoma cells. The fluorescent dye calcein-AM image assay was used to measure the cell viability. Results Bioassay-guided fractionation of the aerial parts of H. hookerianum led to the isolation of 20 previously reported compounds (1-20), including 3 flavonoids (1-3), 2 xanthones (4 and 5), 1 chalcone (6), 4 lignans (7-0), 1 chromone-C-glycoside (11), 1 cinnamic acid derivative (12), 7 phloroglucinols (13-9), and 1 stilbene (20). The structures of the compounds were determined by spectroscopic methods and compared with the reported data. The extracts and isolated compounds showed neuroprotection in both cell models. The compounds 4-hydroxy-2,6,4′-trimethoxydihydrochalcone (6, EC50 = 1.48 µM) and sesamin (10, EC50 = 2.85 µM) exhibited significant neuroprotective effects in HT-22 and SH-SY5Y cells, respectively. Conclusion This is the first report on the neuroprotection of extracts and isolated compounds from H. hookerianum. The results provide information for further studies to develop products for the prevention and treatment of neurological disorders.

Essential oils of two Asteraceae plants Blumea riparia DC. and Pluchea pteropoda Hemsl. ex Hemsl., collected from Vietnam, have been studied by hydro-distillation and GC/MS-FID (gas chromatography/mass spectrometry-flame ionization detector) analysis. Oil yields of B. riparia fresh leaves and twigs were in the range of 0.1–0.2%, whereas essential oil in the fresh aerial parts of P. pteropoda reached about 0.5%. Sesquiterpene hydrocarbons and oxygenated sesquiterpenes were the main chemical classes in the essential oils of B. riparia. The leaves and twigs of this species gave essential oils containing germacrene D (33.6-42.6%), ( E)-β-caryophyllene (11.2-11.6%), and bicyclogermacrene (9.3-12.1%) as the major components. Oxygenated monoterpenes and sesquiterpene hydrocarbons achieved the highest amounts in the essential oil of P. pteropoda aerial parts; 2,5-dimethoxy- p-cymene (43.5%), β-maaliene (14.0%), and α-isocomene (9.0%) were characteristic compounds. Particularly, as compared with related Blumea and Pluchea species, B. riparia and P. pteropoda, collected from Vietnam, might be good sources of germacrene D and 2,5-dimethoxy- p-cymene, respectively. The essential oil of B. riparia leaf successfully controlled the growth of the fungus Fusarium oxysporum, with an MIC value of 50.0 µg/mL, and the essential oil of P. pteropoda aerial parts showed significant antimicrobial activity against the Gram positive bacterium Bacillus subtilis and the yeast Candida albicans, with the same MIC value of 50.0 µg/mL.

The anti-cancer activity of bannaxanthone E isolated from Garcinia mckeaniana leaves was assessed through a flow cytometric method on human lung SK-LU-1 cancer cells, including cell cycle changes and induction of cell apoptosis. Treatment with bannaxanthone E led to the suppression of cell cycle progression at the G2/M phase to 19.6% at 4 µM, and induced apoptosis via cell morphological changes, increased the fluorescence signal in caspase-3/7 activation, and accumulation of apoptotic cells in the SK-LU-1 line at 4 µM to 25.7%.

Novel 1,4-pyranonaphthoquinone derivatives were successfully synthesized via the microwave-assisted three-component reaction of 1,4-naphthoquinone, malononitrile, and various arylaldehydes in ethanol in the presence of 4-(dimethylamino)pyridine (DMAP) as a catalyst, and subsequently evaluated in terms of their antimicrobial and antifungal activities. This synthetic procedure has the notable advantages of environmental friendliness, short reaction time, good yield, and convenient operation.

Plants of the genus Polyalthia can be seen as a rich resource of essential oils type terpenoids. In this study, the essential oils obtained by hydro-distillation from the leaf and stem of Polyalthia viridis were analysed by gas chromatography/mass spectrometry–flame ionization detection. Thirty-nine constituents (95.3%) were identified in the leaf oils and 42 constituents (90.9%) in the stem oils. Sesquiterpene hydrocarbons and oxygenated sesquiterpenes were the main constituents of both oils, in which 2 sesquiterpene hydrocarbons, germacrene D (45.1%-47.4%) and bicyclogermacrene (8.2%-17.1%), were the 2 major compounds. The stem oils inhibited the growth of 3 cancer cell lines, HepG2, MCF7, and A549, with half inhibitory concentration (IC50) values of 56.7 to 68.4 μg/mL. The stem oils also successfully suppressed the growth of the filamentous fungus Aspergillus niger and the yeast Candida albicans with minimum inhibitory concentration values of 50 μg/mL. P viridis oils suppressed NO production in lipopolysaccharide-stimulated BV2 microglial cells, with IC50 values of 57.6 to 76.7 μg/mL.

For the first time the 4-dimethylaminopyridine (DMAP) catalyzed straightforward and efficient procedure has been developed for the synthesis of 3,3′-(arylmethylene) bis(2-hydroxynaphthalene-1,4-dione) derivatives starting from lawsone (2-hydroxy-1,4-naphthoquinone) and a variety of (hetero)aromatic aldehydes in ethanol under microwave irradiation. Three of nine synthesized compounds are new. This method provides notable advantages over existing procedures including use of non-traditional basic catalyst and environmentally benign solvent, mild reaction conditions, excellent yields, short reaction time and simple workup.

Seven novel N-alkyl-plinabulin derivatives with aryl groups moieties (nitroquinoline, 1,4-dihydroquinoline, 4-methoxybenzene, and 4-chlorobenzene) have been synthesized via aldol condensation and alkylation in one-pot, and tested for their cytotoxicity against 4 cancer cell lines (KB, HepG2, Lu, and MCF7). Compounds ( Z)−3-((6,8-dimethyl-4-oxo-1,4-dihydroquinolin-2-yl)methylene)−6-(( Z)−4-methoxybenzylidene)−1-(prop-2-yn-1-yl)piperazine-2,5-dione (5a), ( Z)−6-(( Z)−4-methoxybenzylidene)−1-(prop-2-yn-1-yl)−3-((1,6,8-trimethyl-4-oxo-1,4-dihydroquinolin-2-yl)methylene)piperazine-2,5-dione (5b), and ( Z)−3-(( Z)−4-chlorobenzylidene)−1,4-dimethyl-6-((8-methyl-4-nitroquinolin-2-yl)methylene)piperazine-2,5-dione (8) showed strong cytotoxicity against 3 of the cancer cells lines (KB, HepG2 and Lu) with IC50 values ranging from 3.04 to 10.62 µM. The quinoline-derived compounds had higher cytotoxic activity than the benzaldehyde derivatives. The successful synthesis of these derivatives offers useful information for the development of more potent vascular disrupting agents based on plinabulin.

Zanthoxylum nitidum (Roxb.) DC is a traditional Vietnamese medicine to treat coughs, stomachache, toothache, blood stagnation, and sore throats. The essential oils (EOs) of the leaves, fruits, and stems of this plant were extracted by hydrodistillation and subjected to analysis by gas chromatography (GC)-flame ionization detector (FID) and GC-mass spectrometry (MS). The isolated EOs were then evaluated in terms of their antimicrobial activity by minimum inhibitory concentration (MIC) assay and in vitro cytotoxic effect against 5 human tumor cell lines. GC-MS-FID analysis showed 35, 32, and 25 compounds accounting for 97.6%, 91.7%, and 96.2% of the total EO contents from the leaves, fruits, and stems, respectively. The major compounds of the leaf EO were limonene (44.3%), β-caryophyllene (12.5%), linalool (11.0%), germacrene D (5.3%), and α-pinene (4.9%); the major compounds of the fruit EO were n-pentadecane (34.8%), sabinene (18.3%), and n-heptadecane (4.7%), and the major components of the stem EO were 2-undecanone (72.3%), β-caryophyllene (5.8%), and germacrene D (4.0%). The EOs of leaves, fruits, and stems of Z. nitidum exhibited antibacterial activity against Bacillus subtilis, Escherichia coli, and Fusarium oxysporum with MIC values of 100 µg/mL. The leaf and branch EOs exhibited cytotoxic activity against all tested cancer cell lines, especially A-549 and HepG-2. Findings from the present study provide important knowledge about the potential uses of Z. nitidum EOs as a natural antibacterial and antitumor agents.

The efficacy of Truong Xuan Cao Bang (TXCB), a Vietnamese herbal medicine prescription, on the quality of semen, serum testosterone (TES), and malondialdehyde (MDA) concentrations in rabbits whose reproductive ability were impaired by fluconazole was investigated. Mature male rabbits were randomly assigned into control (G1), fluconazole (G2), fluconazole and 180 mg/kg/day (G3), and 360 mg/kg/day TXCB (G4) groups. The reaction time (RT), ejaculate volume (EV), sperm concentration (SC), total sperm output (TSO), total sperm motility (TSM), progressive sperm motility (PSM), nonprogressive sperm motility (NPSM), sperm immobility (SIM), dead sperm (DS), and abnormal sperm (AS) levels were determined after TXCB administration. After 60 days, G3 showed a significant increase in serum TES and a significant decrease in the concentrations of serum MDA (SMDA) and seminal plasma MDA (SPMDA) compared with G1, in addition to increase in EV, SC, TSO, TSM, PSM, and serum TES, and decrease in RT, SIM, DS, AS, SMDA, and SPMDA compared with G2. G4 showed a steep rise in EV, SC, and serum TES and a downturn in DS, SMDA, and SPMDA compared with G1, and, compared with G2, a significant increase in EV, SC, TSO, TSM, PSM, and serum TES and a significant decrease in RT, SIM, DS, AS, SMDA, and SPMDA. Taken together, TXCB rehabilitates and simultaneously enhances spermatogenesis in rabbits whose reproductive ability was impaired by fluconazole.

From the leaves of Aralia chinensis, 3 oleanane-type triterpene glycosides have been isolated, including 1 new glycoside, 3β,23 -dihydroxyolean-12-ene-28-oic acid 3 -O-β-d-glucopyranosyl-(1→3)- α-l-arabinopyranosyl-(1→3)-β-d-glucuronopyranoside 28 -O-β-d-glucopyranosyl ester (named as araliachinoside A, 1), and 2 known ones, 3β,23 -dihydroxyolean-12-ene-28-oic acid 3 -O-α-l-arabinopyranosyl-(1→3)- β-d-glucuronopyranoside 28 -O-β-d-glucopyronosyl ester (2) and 3β-hydroxyolean-12-ene-28-oic acid 3 -O-β-d-glucurono pyranoside 28 -O-β-d-glucopyronosyl ester (3). Their chemical structures were elucidated by using a combination of high-resolution electrospray ionization-mass spectrometry, 1-dimensional and 2-dimensional nuclear magnetic resonance spectral data, and by comparison with previous literature. Compounds 1-3 displayed cytotoxic activity toward KB and HepG2 cell lines with half-maximal inhibitory concentration values ranging from 8.1 ± 0.1 to 15.7 ± 0.3 µM in in vitro assay.

One new oleanane-type triterpene glycoside, oleanolic acid-[28 -O-β-d-glucopyranosyl]-3 -O-[ β-d-glucopyranosyl(1→6)- β-d-glucopyranosyl](1→3)[ α-l-arabinofuranosyl(1→4)]- β-d-glucuronopyranoside (1), and 3 known ones {oleanolic acid-[28 -O-β-d-glucopyranosyl]-3 -O-[ β-d-galactopyranosyl(1→3)]-[ β-d-glucopyranosyl(1→2)]- β-d-glucuronopyranoside (2) chikusetsusaponin IVa methyl ester (3), and chikusetsusaponin IV (4)} were isolated from the leaves of Aralia armata. Their chemical structures were elucidated using a combination of high-resolution electrospray ionization mass spectrometry, 1-dimensional and 2-dimensional nuclear magnetic resonance (NMR) spectral data, as well as comparison with data in the previous literature. This is the first report of full NMR spectroscopic data of 2. Compounds 1-4 displayed weak cytotoxic activity toward KB and HepG2 cell lines, with half-maximal inhibitory concentration50 values ranging from 24.2 ± 0.3 to 32.6 ± 0.8 µM in in vitro assay.

A series of new hydroxamate derivatives of lupane triterpenoids has been designed and successfully synthesized. The synthesized compounds were evaluated for their in vitro antitumor activity using the 3-[4,5-dimethylthiazol-2-yl]−2,5-diphenyltetrazolium bromide-based assay against the human cancer cell lines KB and HepG2. Most of these derivatives possess at least moderate cytotoxic activity and the hydroxamate derivative compounds 3c, 3e, 7a, and 15b could be lead compounds for further optimization to develop novel anticancer agents.

Dihydroartemisinin was converted to its corresponding alkyne-functionalized esters, which were subsequently deployed as substrates for a 'click' chemistry-mediated coupling-with 3'-azido-3'-deoxythydimine (AZT) to furnish novel triazole-artesunate-AZT hybrid compounds. Moreover, various substituted triazole-artemisinin :hybrids were synthesized based on 'click' chemistry between propargyl-substituted derivatives and artemisinin containing a 2-hydroxypropane unit. Fourteen new hybrids were thus successfully prepared and evaluated as cytotoxic agents, revealing an interesting anticancer activity of four triazole-artemisinin derivative hybrids in KB and HepG2 cancer cell lines.

A new flavonoid, sexangularetin 3- O-(2″- O-( E) -p-coumaroyl-β -d-glucopyranoside) (1), together with 9 known flavonoid compounds (2-10), was isolated from flowers of Camellia hakodae Ninh. Their structures were established based on physicochemical and spectroscopic analyses. The new compound displayed moderate to weak cytotoxic activities against HepG2 (IC50 192.0 μg/mL), Lu (IC50 90.2 μg/mL), and KB (IC50 72.7 μg/mL) cell lines, and inactivity against MCF7 (IC50 256.0 μg/mL).

A new benzofurane 7-methoxy-2-(3-hydroxy-4-methoxyphenyl)-benzofuran-5-carboxylate (1) and 5 known compounds, such as propacin (2), hisbiscolatone A (3), heliclactone (4), rosmarinic acid (5), and syringaldehyde (6), were isolated from methanol extract of the Helicteres hirsuta stems. Their structures were elucidated by spectroscopic analysis as Nuclear Magnetic Resonance (NMR) and Mass Spectroscopy (MS) Furthermore, compounds 1 to 6 were evaluated for their cytotoxic activity against 4 human cancer cell lines such as Lu-1, MCF7, HepG2, and KB. The results showed that compound 2 exhibited moderate cytotoxic activity against Lu-1, MCF7, HepG2, and KB cell lines with IC50 values of 43.97 ± 2.12, 46.53 ± 0.75, 52.63 ± 0.24, and 56.37 ± 1.04 µg/mL, respectively. This is the first report of compounds 2 to 6 from H. hirsuta.

Zanthoxylum nitidum (Roxb.) DC (Rutaceae) is a traditional medicine used for the treatment of various diseases like toothache, gingivitis, fever, colic vomiting, diarrhea, and cholera. Three new alkaloids, zanthocadinanine C (1), 7-methoxy-8-demethoxynitidine (2), and zanthonitiside I (3) were isolated from the stems and twigs of Z. nitidum. Their structures were determined on the basis of extensive spectroscopic, including 1-dimensional and 2-dimensional nuclear magnetic resonance and mass spectroscopy data. Compounds 1–3 were evaluated for cytotoxic activity against 5 human cancer cell lines, KB, MCF-7, LNCaP, HepG-2, and LU-1. Compound 2 showed significant cytotoxic activity against all tested human cancer cell lines with IC50 values ranging from 10.3 to 12.6 µM.

In order to find out the influence of carboxylic acid functionalities in the N-lactam side chains of indenoisoquinolines on cytotoxic activities, several new compounds have been synthesized and structurally characterized by analytical and spectral methods. The incorporation of a carboxylic acid group into the lactam side chain of indenoisoquinolines results in differences in cytotoxicity. The results indicated that compound 18c displayed substantial cytotoxic specificity toward KB and HepG2 cancer cells.

Hemiasterlin is a potent antimitotic agent acting through inhibition of microtubule depolymerization. For this reason, the synthesis of new hemiasterlin derivatives has attracted a lot of interest in the organic chemistry community recently. In this paper, the synthesis and evaluation of the cytotoxicity of new simplified and racemic hemiasterlin derivatives were reported. All of the synthesized analogues were evaluated in vitro for cytotoxic activity against four human cell lines (KB, Hep-G2, LU and MCF7). Most of these analogues possess a strong cytotoxic activity on two human cancer cell lines (KB and Hep-G2) and very weak activity on LU and MCF7 cell lines.

A series of 4-anilinoquinazoline–triazole–AZT hybrids were designed and synthesized as anticancer agents. Their cytotoxic potential has been evaluated by means of a micro-dilution assay against three human cancer cell lines (KB, epidermoid carcinoma; HepG2, hepatoma carcinoma; SK-Lu-1, non-small lung cancer). The biological results revealed that compounds 4b and 6d showed good anticancer activities against KB, HepG2, and Lu cell lines (IC50 values ranging from 9 μM to 100 μM). Especially, compounds 4b and 6d exhibited up to 3-fold more potent than reference drugs erlotinib hydrochloride and AZT in term of anti-lung cancer activity.