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From the aerial parts of Eupatorium fortunei, four thymol derivatives (1-4) were isolated and structurally elucidated by NMR and mass spectroscopic methods. Of which, a new dimeric thymol derivative (1) was characterized and its absolute configuration was established by electronic circular dichroism quantum method. In addition, the 1D and 2D NMR as well as HR-ESI mass spectral data of 2 were provided for the first time. Compounds 2-4 were evaluated for their inhibitory activity against α-glucosidase and acetylcholinesterase enzymes. All tested compounds showed weak inhibition at the concentration range of 1–256 μg/mL in both enzymatic assays.

In this study, we optimized the fermentation medium for spore production of Paenibacillus polymyxa IN937a. Seven factors including molasses, glucose, magnesium sulfate, potassium pyrophosphate, yeast extract, zinc sulfate, and ammonium sulfate are selected as the basis for the screening of factors affecting the spore production of P. polymyxa IN937a by the Plackett-Burman experiment. Based on the analysis of the Plackett-Burman matrix, the result showed that yeast extract, molasses, and ammonium sulfate were the three main impact factors (P < 0.05), which affected the yield of P. polymyxa IN937a spores. Then, the optimum combination of the three factors was subsequently optimized by the response surface methodology (RSM) using Box-Behnken design to increase the spore production in P. polymyxa IN937a fermentation. The obtained results by RSM predicted that maximum spore density of P. polymyxa IN937a was 6.606×109 spore/mL after 48 hours of the experiment when the appropriate medium for the spore production of P. polymyxa IN937a included yeast extract 14.44 g/L, molasses 19.14 g/L, and ammonium sulfate 0.20 g/L. In addition, the antifungal activity of P. polymyxa IN937a was also tested in this study. The preliminary results of in vitro antifungal activity indicated that P. polymyxa IN937a had a good inhibition on the growth of two phytopathogenic fungal strains Sclerotium rolfsii and Rhizoctonia solani. These results could be used for further research on the fermentation of P. polymyxa IN937a on a pilot scale to obtain the optimal number of spores for use in the development of biological crop protection products.

Five new 4-aza-2,3-didehydropodophyllotoxins were synthesized by a straightforward multi-component reaction in the hope of finding new structures with interesting anticancer activity. The “one-pot” synthesis process is developed to increase performance as well as minimize the steps involved. The obtained compounds with podophyllotoxin frame have the corresponding yields of 60-83%. Five new 4-aza-2,3-didehydropodophyllotoxins demonstrated comparable cytotoxicity against the Hep-G2, MCF7cell lines with an IC50 value of 52.2 - 261.2 µM with ellipsitine as the positive control.

A phytochemical investigation of methanol extract from leaves of Pachyrhizus erosus (L.) Urban, a leguminous shrub distributed in Vietnam and other tropical and subtropical countries led to the isolation of a new prenylated chalcone, erosusone (1) and a new megastigmane glycoside epimer, 3-episedumoside F1 (9), together with thirteen known compounds including flavonoids (2-6), a 3-benzoxepine lactone (7), a pyridine-4,5-diol derivative (8), megastigmanes and megastigmane glycosides (10-15). Their structures were elucidated by means of high resolution-electrospray ionization (HR-ESI)-MS, one dimensional (1D) and two-dimensional NMR (2D-NMR) spectroscopy as well as comparison with the data reported in the literature. The cytotoxic effects on LU-1 (lung carcinoma), HepG2 (hepatocellular carcinoma), and MCF7 (breast carcinoma) cell lines were assessed. Prenylated chalcones 1-2 and isoflavone 3 exhibited cytotoxicity against all tested cell lines with IC50 values ranging from 22.04 to 45.03 µM.

Phytochemical investigation of methanol extract from

Two new chlorinated guaianane-type sesquiterpenes (named chlosigesolides A and B) together with eight known compounds were isolated from the leaves and twigs of

Nine bioactive compounds, including one new dihydroisocoumarin glycoside, 3S-thunberginol C 6-O-β-D-glucopyranoside (1a/1b), were isolated by chromatographic separation from the fruits of the Vietn...

Phytochemical study on the methanolic extract of the leaves of Vietnamese plant

Two new chlorinated guaianane-type sesquiterpenes (named chlosigesolides A and B) together with eight known compounds were isolated from the leaves and twigs of Sigesbeckia orientalis. Their structures were determined by analysis of HR-ESI-MS, 1D- and 2D-NMR spectral data as well as comparison with the literature. Absolute configurations of new compounds were elucidated by NOESY and ECD methods. Chlosigesolide A inhibited NO production in LPS-stimulated RAW264.7 macrophages with IC50 value of 10.9 ± 0.8 μM. Other compounds exhibited inhibitory activity at IC50 in range of 26.5 to 49.7 μM.

Three sesquiterpene lactones (1–3) were isolated from the aerial part of Tithonia diversifolia (Hemsl.) A. Gray grown in the Hoa Binh province in Viet Nam. The structures of these three sesquiterpene lactones were identified as tagitinin A (1), 1β-hydroxytirotundin 3-O-methyl ether (2), and tagitinin C (3) by analyzing spectroscopic data. For the first time, compound 2 was isolated from T. diversifolia growing in Viet Nam. Furthermore, contrary to existing literature, we determined that compound 1 was the major isolate. Compounds 1 and 3 significantly decreased numbers of acute myeloid leukemia OCI-AML3 cells by promoting apoptosis and causing cell cycle arrest at G0/G1 phase at concentrations as low as 2.5 μg/mL (compound 1) and 0.25 μg/mL (compound 3). Additionally, all three compounds showed cytotoxic activity against five human cancer cell lines (A549, T24, Huh-7, 8505, and SNU-1), with IC50 values ranging from 1.32 ± 0.14 to 46.34 ± 2.74 μM. Overall, our findings suggest that compounds 1 and 3 may be potential anti-cancer therapeutics and thus warrant further study.

A new sesquiterpene glucoside (

A phytochemical investigation of methanol extract from leaves of Pachyrhizus erosus (L.) Urban, a leguminous shrub distributed in Vietnam and other tropical and subtropical countries led to the isolation of a new prenylated chalcone, erosusone (1) and a new megastigmane glycoside epimer, 3-episedumoside F

Elaeocarpus hainanensis has been used in the Oriental medicine but there are very few studies on its phytochemical profile. Our ongoing research on chemical constituents from Elaeocarpus plants in Vietnam led to the isolation of a new oleanane-type saponin from the aerial part of E. hainanensis. Its structure was identified as 1α-hydroxy-olean-11-oxo-12-en-3-O-β-L-arabinopyranoside (1) on the basis of extensive chemical and spectroscopic analyses including NMR and MS spectra. The occurence of the unique oleanane-type saponins in E. hainanensis contributed to impact phytochemical profile associated with chemotaxanomy meaning of the title plant.

Four new alkaloid glycosides, zanthonitisides A–D (1-4), together with five known compounds (5–9) were isolated from the aqueous fraction of stems and twigs of Zanthoxylum nitidum (Roxb.) DC. Their structures were determined on the basis of extensive spectroscopic methods, including 1D-, 2D-NMR, MS, and CD data. All isolated compounds were evaluated for their cytotoxic activity against three human cancer cell lines, CT-26, MCF-7, and MKN-45. As results, compound 4 showed significant cytotoxic activity on MKN-45 cancer cell line with IC50 value of 7.4 ± 1.0 μM. Compound 9 exhibited moderate cytotoxic activity on all tested cancer cell lines with an IC50 values ranging from 34.7 to 44.7 μM.

Three sesquiterpene lactones (

Various Elaeocarpus species including Elaeocarpus tonkinensis have been important medicinal plants that used in traditional medication system and mainly used to cure nervous system-related disorders. However, their antiviral potential has not been reported yet. During the screening of medicinal plant extracts with the antiviral activity against influenza viruses, we found that E. tonkinensis extract has strong antiviral activity. Through organic solvent partition and repeated column chromatography using SiO 2, C-18 and Sephadex LH-20, a total of nine compounds were purified from the methanol extract of E. tonkinensis. Their chemical structures were determined by NMR and MS spectral data to be trolliamide (1), gallic acid (2), urolithin M-5 (3), hydroquinone (4), 2,4-dihydroxybenzoic acid (5), 3,5-dihydroxy-4-methoxybenzoic acid (6), corilagin (7), chebulagic acid (8), and shikimic acid (9). Their antiviral activity against influenza virus strains A/Puerto Rico/8/34 (H1N1; PR8), A/Hong Kong/8/68 (H3N2; HK) and B/Lee/40 (Lee) was examined on the basis of cytopathic effect (CPE) assay. Among them, compounds 2, 3, 4, 7, and 8 significantly inhibited viral replication in a dose-dependent manner with EC 50 values ranging from 7.8 to 59.6 μg/mL against influenza A and/or B viruses with selectivity indices above 5.0. This study suggests that the botanical materials of E. tonkinensis could be promising inhibitors of influenza A andB viruses and applied to the development of a novel herbal medicine.

Two new oleanane-type saponins, 1α-hydroxy-olean-12-en-3-O-β-D-xylopyranoside (1) and 1α-hydroxy-olean-12-en-3-O-α-L-arabinopyranoside (2), along with six known compounds (3-8), were isolated from the leaves and twigs of Elaeocarpus hainanensis Oliv. Their structures were determined based on chemical and spectroscopic analyses. This is the first report on oleanane-type triterpenoids in the genus Elaeocarpus.

Panax bipinnatifidus Seem. is a precious medicinal plant belonging to the Araliaceae family. This study qualitatively analyzed saponins of the stem, leaf and rhizome of P. bipinnatifidus by HPLC. Subsequently, by using chromatographic techniques, a major saponin from the leaf of P.bipinnatifidius Seem. was isolated. On the basis of NMR and MS spectroscopic data as well as comparison with those reported in the literature, the isolated saponin’s structure was identified as stipuleanoside R2. To the best our knowledge, this is the first report of saponin from the aerial part of P. bipinnatifidius Seem. Keywords Panax bipinnatifidus, Araliaceae, Stipuleanosid R2, HPLC.. [1] Nguyễn Văn Tập, Các loài thuộc chi Panax L. ở Việt Nam, Tạp chí Dược liệu. 10(3) (2005) 71-76. [2] Nguyễn Văn Tập, Phạm Thanh Huyền, Kết quả nghiên cứu về phân bố, sinh thái sâm vũ diệp và Tam thất hoang ở Việt Nam, Tạp chí Dược liệu. 11(5) (2006) 177-180. [3] Nguyen Huu Tung, Tran Hong Quang, Nguyen Thị Thanh Ngan, Chau Van Minh, Bui Kim Anh, Pham Quoc Long, Nguyen Manh Cuong, Young Ho Kim, Oleanolic triterpenesaponins from the roots of Panax bipinnatifidus, Chem Pharm Bull (Tokyo). 59(11) (2011) 1417-1420. [4] Đỗ Văn Hào, Nguyễn Thị Huệ, Nguyễn Thị Thu Thủy, Đặng Thị Ngần, Đào Thị Hồng Bích, Nguyễn Thị Hoàng Anh, Dương Thị Ly Hương, Nguyễn Hữu Tùng, Thành phần hóa học của phân đoạn ethyl acetat từ rễ cây sâm vũ diệp (Panax bipinnatifidus Seem.) thu hái ở Sa Pa, Lào Cai, Tạp chí Khoa học ĐHQGHN - Khoa học Y Dược. 33(2) (2017) 50-55. [5] Nguyễn Thị Thu Thủy, Nguyễn Thị Huệ, Đặng Thị Thùy, Nguyễn Thị Hoàng Anh, Dương Thị Phượng, Phạm Thị Tuyết Nhung, Hà Vân Oanh, Dương Thị Ly Hương, Nguyễn Hữu Tùng, Thành phần saponin của thân rễ sâm vũ diệp thu hái ở Sa Pa, Lào Cai, Tạp chí Dược liệu. 23(2) (2018) 82-88.[6] Wen-zhi Yang, Ying Hu, Wan-ying Wu, Min Ye, De-an Guo, Saponins in the genus Panax L. (Araliaceae): A systematic review of their chemical diversity, Phytochemistry. 106 (2014) 7-14. [7] Shashi B. Mahato, Asish P. Kundu, 13C NMR spectra of pentacyclic triterpenoids - a complication and some salient features, Phytochemistry. 37 (1994) 1517-1575. [8] Pawan K. Agrawal, NMR spectroscopy in the structural elucidation of oligossacharides and glycosides, Phytochemistry. 31 (1992) 1307-1330. [9] Chun Liang, Yan Ding, Huu Tung Nguyen, Jeong-Ah Kim, Hye-Jin Boo, Hee-Kyoung Kang, Mahn Cuong Nguyen, Young Ho Kim, Oleanane –type triterpenoids from Panax stipuleannatus and their anticancer activities, Bioorg Med Chem Lett. 20 (2010) 7110-7115.

Panax bipinnatifidus Seem. (Araliaceae), 1 of 11 kinds of ginseng (Panax spp.), has been used in traditional medicine but there are very few publications regarding its chemical constituents. This f...

A new chromone, 5,7-dihydroxy-6,8-dimethoxy-2-methyl-4H-chromen-4-one (1), together with seven known compounds, 5,7-dihydroxy-6-methoxy-2-methyl-4H-chromen-4-one (pisonin B) (2), 5,7-dihydroxy-2-methyl-4H-chromen-4-one (noreugenin) (3), 5-hydroxy-7-methoxy-2-methyl-4H-chromen-4-one (eugenin) (4), (2S)-7,4'-dihydroxyflavan (5), 3',7-dihydroxy-4'-methoxy-8-methylflavan (6), 3',7-dihydroxy-4'-methoxyflavan (7) and 6,8-dimethyl-5,7,4'-trihydroxyflavanone (( - )-farrerol) (8), were isolated from Hymenocallis littoralis Salisb. (Amaryllidaceae) growing in Vietnam. Their structures were determined based on spectroscopic and physicochemical analyses.

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 coumaronochromone derivative, boeravinone R (5,7-dihydroxy-3´-methoxy-coumaronochromone) (1), together with 4 known compounds: β-sitosterol (2), oleic acid (3), physcion (4), and glutinol (5)...

A series of Novel Mannich bases has been synthesized and evaluated in vitro cytotoxic activity against the human hepatocellular carcinoma (HepG2), human lung carcinoma (SK-LU-1), and human breast cancer (MCF-7). Compound 9f was found to be most potent against three cell lines with IC50 values of 1.57, 1.16 and 1.21 µg/mL, respectively. In addition, compounds 9g, 10f exhibited very significant activity against MCF-7 cell line with IC50 values of 2.0 µg/mL.

A series of novel quinolinylhydrazones (5a-f) was synthesized by the condensation reaction of 2,6-diaryl- substituted piperidin-4-ones (4a-f) with 7-chloro-4-hydrazinoquinoline (2). Novel quinolinylhydrazones containing Shiff bases 8a-f and 11a-f were obtained via the condensation of Shiff bases 7a-f and 10a-f with 7-chloro-4-hydrazinoquinoline. These synthesized hydrazones were screened for their in vitro antimalarial activities to chloroquine - sensitive (T96) and chloroquine - resistant (K1) strains of P.falciparum. Among the synthesized compounds, 11a exhibited strong antimalarial activity at IC50 of 103.4 ng/mL and 18.76 ng/mL to both strains of P.falciparum, respectively.

In a continuing search for anti-HIV compounds from plants of Vietnam, 19 compounds, including a new triterpene, were isolated from an extract of the leaves and stem of Vatica cinerea. The new triterpene was determined to be a cycloartane triterpenoid with 29 skeletal carbons and was assigned the name vaticinone (1). The known triterpenes included three cycloartanes, a lanostane, two dammaranes, three lupanes, an ursane, and an oleanane. A chlorophyll isolate was identified as pheophorbide a (13). The majority of the triterpenes, the sesquiterpene, 1-hydroxycyclocolorenone, and pheophorbide a showed anti-HIV activity, with the chlorophyll being the most active, demonstrating an IC(50) value of 1.5 microgram/mL (2.5 microM), while being completely devoid of toxicity up to a concentration of 20 microgram/mL (33.8 microM). Vaticinone (1) was found to inhibit the replication of HIV-1, with an IC(50) value of 6.5 microgram/mL (15.3 microM; selective index = 1.4). The structures of these isolates were determined by spectral data including 1D and 2D NMR spectra.

The eudesmane sesquiterpenoid, verticillatol (1), as well as the lignan, (+)-5'-demethoxyepiexcelsin (2), and a known lignan, (+)-epiexcelsin (3), were isolated from Litsea verticillata Hance. Lignan 2 showed moderate anti-HIV activity with an IC(50) value of 16.4 microg/ml (42.7 microM), while the known lignan 3 was inactive up to a concentration of 20 microg/ml (48.3 microM). Compound 1 demonstrated weak activity with an IC(50) value of 34.5 microg/ml (144.7 microM) while being devoid of cytotoxicity at 20 microg/ml. The structures were elucidated by 1D and 2D NMR spectroscopy, and the absolute configuration of the new sesquiterpenoid was determined by the generation of Mosher esters.

We report herein the first isolation of a novel structural type sesquiterpene designated as ‘litseane’ from the twigs and leaves of Litsea verticillata Hance (Lauraceae). The isolate (litseaverticillol A, 1 ) was obtained as a racemate through bioassay-guided fractionation and found to inhibit the replication of human immunodeficiency virus (HIV) type 1 with an IC 50 value of 5.0 μg/mL (21.4 μM) and a selectivity index of 2.6. Spectroscopic data and a potential biosynthetic pathway are given.

A simple method was introduced to prepare magnetic chitosan nanoparticles by co-precipitation via epichlorohydrin cross-linking reaction. The average size of magnetic chitosan nanoparticles is estimated at ca. 30 nm. It was found that the adsorption of Cr(VI) was highly pH-dependent and its kinetics follows the pseudo-second-order model. Maximum adsorption capacity (at pH 3, room temperature) was calculated as 55.80 mg·g(-1), according to Langmuir isotherm model. The nanoparticles were thoroughly characterized before and after Cr(VI) adsorption. From this result, it can be suggested that magnetic chitosan nanoparticles could serve as a promising adsorbent for Cr(VI) in wastewater treatment technology.

[reaction: see text] A novel, nonacetal (trifluoromethyl)deoxoartemisinin was prepared with good stereoselectivity. This compound was obtained by debromination of the 10 alpha-CF3-10-bromodeoxoartemisinin in the presence of tributyltin hydride at reflux in toluene without alteration of the endoperoxide bridge. It presented a reasonable antimalarial activity.

We report herein the first isolation of a novel structural type sesquiterpene designated as ‘litseane’ from the twigs and leaves of Litsea verticillata Hance (Lauraceae). The isolate (litseaverticillol A, 1 ) was obtained as a racemate through bioassay-guided fractionation and found to inhibit the replication of human immunodeficiency virus (HIV) type 1 with an IC 50 value of 5.0 μg/mL (21.4 μM) and a selectivity index of 2.6. Spectroscopic data and a potential biosynthetic pathway are given.