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Summary Single-molecule magnets (SMMs) exhibit magnetization blocking in the presence of strong magnetic anisotropy. By employing molecular engineering, the blocking barrier can be significantly modified, remaining independent from other external factors, such as magnetic field. Taking advantage of hyperfine coupling of electronic and nuclear spins further highlights their unique functionality. However, a poor understanding of relaxation mechanisms limits the exploitation of nuclear-spin molecular qubits. Here, we report the first observation of field-dependent oscillation of the magnetization blocking barrier in a holmium metallacrown magnet driven by the switch of relaxation mechanisms involving hyperfine interaction. First-principles calculations reveal an activated temperature dependence of magnetic relaxation, dominated either by incoherent quantum tunneling of magnetization at anti-crossing points or by Orbach-like processes at crossing points. This mechanism demonstrates that these relaxation barriers can be consecutively switched by increasing the external field, which paves a way for manipulating magnetization dynamics of SMMs using hyperfine interaction.

A new ursane-type triterpene, 3β,23,24-trihydroxyurs-12-en-28-oic acid (1), together with eight known compounds (2–9) were isolated from the aerial parts of Ophiorrhiza baviensis. Among them, compounds 2–5 were found for the first time from the genus Ophiorrhiza, while compounds 6–9 were reported from O. baviensis for the first time. Their structures were elucidated by analysis of HR-ESI-MS and NMR (1H-NMR, 13C-NMR, HSQC, and HMBC) spectra, as well as comparison with those reported in the literature. Moreover, all isolated compounds were evaluated for their cytotoxic activities against MCF-7, Hela, KB, A549, and SK-LU-1 cancer cell lines and their effects on LPS-induced NO production in RAW264.7 cells. This is the first report of chemical constituents and biological activities of O. baviensis.

Two efficient and practical approaches are reported for the synthesis of β- and δ-carbolines from 3,4-dibromopyridine. The synthesis is based on site-selective Cu-catalyzed double C–N coupling reactions and subsequent annulations by twofold Pd-catalyzed C–N coupling with amines.

A new compound, physalucoside A (1), together with seven withanolides (2-8) and three flavonoids (9-11), were isolated from Physalis angulata L. (Solanaceae), a medicinal plant native to Vietnam. The chemical structures of these compounds were elucidated by one- and two-dimensional NMR spectra, high-resolution electrospray ionization mass spectrometry analyses, and chemical reactivity. The anti-inflammatory and cytotoxic activities of isolated compounds were also evaluated. These data suggest that the anti-inflammatory activity of P. angulata is due primarily to its withanolide content. This study demonstrates the potential of withanolides as promising candidates for the development of new anti-inflammatory drugs.

Many chemicals found in mangroves reportedly exhibit potent anticancer, antibacterial, anti-inflammatory, antioxidant, and antitumor properties. Several of such compounds include feature unique structures and display interesting pharmacological effects. Few medicinal mangrove plants from Vietnam have been characterized with regard to their chemical constituents. Aegiceras corniculatum (L.) Blanco is a mangrove shrub that exhibits activity against various types of cancer. To identify new secondary metabolites and determine the source(s) of biological activity in Vietnamese medicinal mangrove plants, the chemical constituents of A. corniculatum were isolated, and their structures were appropriately established using common spectroscopic methods (1D and 2D-NMR, IR, HR-ESI-MS), and by producing derivatives by chemical reactions. Complementarily, it is worth noting, that the anti-inflammatory effects of the isolated compounds were investigated by measuring the production of pro-inflammatory cytokines IL-12 p40, IL-6, and TNF-α in lipopolysaccharide-stimulated bone marrow-derived dendritic cells; in this sense, the target compounds 2 and 3 were potent inhibitors of cytokines TNF-α, IL-6, and IL-12 p40, indicating promising anti-inflammatory effects. Furthermore, compounds 1 and 4 strongly promoted apoptosis of B16F10 melanoma cells. It is convenient to highlight, that the obtained results suggest that saponins from A. corniculatum could be potential candidates for treating cancer and inflammatory illnesses.

A new steroidal saponin, torvoside R (1), was isolated along with torvoside Q (2) and macaoside (3) from dichloromethane soluble-portion of the aerial parts of Solanum torvum. Their chemical structures were elucidated using HRESIMS, 1 D- and 2 D-NMR as well as comparison with those reported in the literature. All isolated compounds (1 − 3) exhibited cytotoxicity against SK-LU-1, HepG2, MCF-7, and T24 cancer cell lines with IC50 values ranging from 14.18 to 89.31 µg/mL.

In present study, a steam distillation method has been adopted for extraction of the essential oil from Vietnamese lemon (Citrus aurantifolia) peel harvested from Tien Giang Province, Vietnam. Various extraction conditions influencing the oil yield were investigated. The resulting essential oil was evaluated for physico-chemical characteristics and antibacterial activities. The chemic al composition of oil was investigated by GC-MS. The results showed that with grinded lemon peel, a ratio of water and lemon peels of 3:1 (mL/g), extraction time of 90 min at 120 ºC, the highest essential oil yield was attained at 2.1 %. Bioactive components found at high content included limonene (64.90 %), γ-terpinene (13.70 %), β-pinene (11.89 %), α-pinene (2.11 %), β-cymene (1.80 %) and sabinen (1.52 %). The lemon essential oil in this study was found to inhibit five bacteria strains including Staphylococcus aureus, Bacillus cereus, Escherichia coli, Salmonella enterica and Pseudomonas aeruginosa.

Rhodomyrtus tomentosa (Ait.) Hassk is a fruit that is gradually becoming popular in Vietnam with superior bioactive compounds. This study aimed to determine the natural anthocyanins from Rhodomyrtus tomentosa (Ait.) Hassk based on extracts and optimized RSM. The Box-Behnken design was shown the influence of the optimal conditions for the MAE procedure are 5.07 min, 206 W and 2.53 g/mL with the optimal anthocyanin content achieved Y = 133.88 mg/L, all reactions are within the threshold of the predicted value. The results are in line with the proposed model for the anthocyanin extraction (R2 = 0.9849).

A phytochemical investigation of Physalis minima led to the isolation of six withanolides, including withanolide E (1), withaperuvin C (2), 4β-hydroxywithanolide E (3), 28-hydroxywithaperuvin C (4), physaperuvin G (5), and 4-deoxywithaperuvin (6). Their chemical structures were elucidated by 1 D-NMR and 2 D-NMR data, as well as comparison with the data reported in the literature. All isolated compounds were evaluated for their cytotoxic activity against HepG2, SK-LU-1, and MCF7 cancer cell lines. As the obtained results, compounds 1 and 3 displayed the strongest cytotoxicity against HepG2, SK-LU-1, and MCF7 cell lines with IC50 value ranging from 0.051 ± 0.004 to 0.86 ± 0.09 μg/mL.

Three new binuclear FeIII–LnIII complexes, with similar structures, have been synthesized using the end-off compartmental proligand, H2valpn, resulting from the Schiff condensation between o-vanillin and 1,3-propylenediamine: [FeIIILnIII(valpn)(hfac)2(OAc)Cl] (Ln = Gd, Tb, Dy; hfac− = hexafluoroacetylacetonate; AcO− = acetate). The metal ions are triply bridged by two phenoxido oxygen atoms and by the acetato ligand (syn–syn bridging mode). Among all these compounds the FeIII–LnIII exchange interaction was found to be ferromagnetic (JFeGd = +1.004(4) cm−1; H = −JSFeSGd). The [FeIIIDyIII] derivative shows field-induced slow relaxation of the magnetization. The interpretation of the magnetic properties for the [FeIIIGdIII], [FeIIITbIII] and [FeIIIDyIII] is done through ab initio calculations. It was concluded that the temperature behavior of the relaxation time in the [FeIIIDyIII] derivative is due to dominant Orbach relaxation processes between states at the opposite sides and opposite heights of the blocking barrier. From this understanding, the relaxation mechanism for similar systems where a transition metal is in exchange coupling with a strong anisotropic lanthanide ion is elucidated, which could provide a strategy to synthesize other binuclear complexes with better magnetic properties.

We generated a novel G-quadruplex (G4)-specific endonuclease by fusing a G4 recognition domain of the RHAU helicase with a cleavage domain of the Fok1 nuclease. The fusion protein can specifically bind a parallel G4 and cleave a double-stranded DNA (dsDNA) next to it. The new endonuclease could be used to detect a G4 in a long dsDNA, providing a useful tool for mapping the formation of G4s in the genome. Ministry of Education (MOE) Accepted version

Stauntonia hexaphylla (Lardizabalaceae) has been used as a traditional herbal medicine in Korea and China for its anti-inflammatory and analgesic properties. As part of a bioprospecting program aimed at the discovery of new bioactive compounds from Korean medicinal plants, a phytochemical study of S. hexaphylla leaves was carried out leading to isolation of two oleanane-type triterpene saponins, 3-O-[β-D-glucopyranosyl (1→2)-α-L-arabinopyranosyl] oleanolic acid-28-O-[β-D-glucopyranosyl (1→6)-β-D-glucopyranosyl] ester (1) and 3-O-α-L-arabinopyranosyl oleanolic acid-28-O-[β-D-glucopyranosyl (1→6)-β-D-glucopyranosyl] ester (2). Their structures were established unambiguously by spectroscopic methods such as one- and two-dimensional nuclear magnetic resonance and infrared spectroscopies, high-resolution electrospray ionization mass spectrometry and chemical reactions. Their anti-inflammatory activities were examined for the first time with an animal model for the macrophage-mediated inflammatory response as well as a cell-based assay using an established macrophage cell line (RAW 264.7) in vitro. Together, it was concluded that the saponin constituents, when they were orally administered, exerted much more potent activities in vivo than their sapogenin core even though both the saponins and the sapogenin molecule inhibited the RAW 264.7 cell activation comparably well in vitro. These results imply that saponins from S. hexaphylla leaves have a definite advantage in the development of oral medications for the control of inflammatory responses.

The essential oil from the leaves of Paramignya trimera (Oliv.) Guillaum was obtained by hydrodistillation and analysed by Gas Chromatography-coupled with Mass Spectrometry (GC/MS) for the first ti...

A series of 5-aryl-5H-pyrido[2',1':2,3]imidazo[4,5-b]indoles was successfully prepared in good yields by a practical four-step strategy. In this procedure, the key step was demonstrated to be the domino Pd-and Cu-catalyzed C–N coupling reactions of 3-bromo-2-(2-bromophenyl)imidazo[1,2-a]pyridine with amines.

In this study, Ag/Zn2TiO4 powder with uniform size (

A comprehensive phytochemical investigation of the dichloromethane-soluble fraction of Physalis angulata led to the isolation of eight compounds (1–8) including two new withanolides named physagulin P and Q (compounds 5 and 8). Their chemical structures were established using two-dimensional nuclear magnetic resonance (spectroscopy. The cytotoxic activity of these metabolites was investigated against A549, HeLa, and PANC-1 cancer cell lines. Among them, compound 1 showed significant cytotoxic activity against A549 cells with a half-maximal inhibitory concentration (IC50) value of 8.27 μM, while compound 7 showed the most potent activity against PANC-1 cells with an IC50 value of 3.18 μM.

In this work, the isomeric ratio of 152m1Eu(8−)–152m2Eu(0−) produced from the 153Eu(γ, n)152Eu reaction have been measured in the whole giant dipole resonance region by the activation method. In order to improve the accuracy of the experimental results, the necessary corrections were made in the gamma activity measurements and data analysis. The results were discussed and compared with the similar data from literature to examine the excitation energy, the spin difference and the nuclear reaction channel effects and can be used for the interpretation on the structure of the nucleus and the mechanisms of nuclear reactions. The data for bremsstrahlung end-point energies of 19–23 MeV are first-time measurements.

Hypericum sampsonii is an important medicinal plant used in Vietnam to treat many diseases such as backache, burns, diarrhea, and swelling. In order to study the chemical constituents in the aerial...

The title compound, C25H27NO4(I), the product of the unusual thermolysis of azacyclic allene methyl 10,11-dimethoxy-3,8-dimethyl-6-phenyl-3-azabenzo[d]cyclodeca-4,6,7-triene-5-carboxylate, represents a bicyclic heterosystem and crystallizes in the monoclinic space groupP21/cwith three crystallographically independent molecules in the unit cell. These independent molecules adopt very similar geometries and differ only in the conformations of the two methoxy substituents on the benzene ring. In two of the three independent molecules, both methoxy groups are almost coplanar with the benzene ring [the C—C—O—Me torsion angles are 10.8 (2), 12.3 (2), 9.1 (2) and 13.6 (3)°], whereas in the third molecule, one of the methoxy groups is practically coplanar to and the other methoxy group is roughly perpendicular to the benzene ring, the C—C—O—Me torsion angles being 14.1 (2) and 76.5 (2)°. The molecule of (I) comprises a fused tetracyclic system containing two five-membered rings (cyclopentenes) and two six-membered rings (piperidine and benzene). The five-membered rings have the usual envelope conformation, with the methyl-subsituted C atom as the flap in each molecule, and the six-membered piperidine ring has a chair conformation. The methyl substituent at the N atom occupies the sterically favourable equatorial position. The carboxylate group lies almost within the basal plane of the parent cyclopentene ring [making dihedral angle of 11.68 (8), 18.94 (9) and 15.16 (9)° in the three independent molecules], while the phenyl substituent is twisted by 48.26 (6), 42.04 (6) and 41.28 (6)° (for the three independent molecules) relative to this plane. In the crystal, molecules of (I) form stacks along theb-axis direction. The molecules are arranged at van der Waals distances.

The bitter melon, Momordica charantia L., was once an important food and medicinal herb. Various studies have focused on the potential treatment of stomach disease with M. charantia and on its anti-diabetic properties. However, very little is known about the specific compounds responsible for its anti-inflammatory activities. In addition, the in vitro inhibitory effect of M. charantia on pro-inflammatory cytokine production by lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs) has not been reported. Phytochemical investigation of M. charantia fruit led to the isolation of 15 compounds (1−15). Their chemical structures were elucidated spectroscopically (one- and two-dimensional nuclear magnetic resonance) and with electrospray ionization mass spectrometry. The anti-inflammatory effects of the isolated compounds were evaluated by measuring the production of the pro-inflammatory cytokines interleukin IL-6, IL-12 p40, and tumor necrosis factor α (TNF-α) in LPS-stimulated BMDCs. The cucurbitanes were potent inhibitors of the cytokines TNF-α, IL-6, and IL-12 p40, indicating promising anti-inflammatory effects. Based on these studies and in silico simulations, we determined that the ligand likely docked in the receptors. These results suggest that cucurbitanes from M. charantia are potential candidates for treating inflammatory diseases.

Chemical investigation of an acidic methanol extract of the whole plants of Datura metel resulted in the isolation of two new guainane sesquiterpenes, 1β,5α,7β-guaiane-4β,10α,11-triol ( 1 ) and 1α,5α,7α-11-guaiene-2α,3β,4α,10α,13-pentaol ( 2 ), along with eight known compounds: pterodontriol B ( 3 ), disciferitriol ( 4 ), scopolamine ( 5 ), kaempferol 3- O -β- d -glucosyl(1 → 2)-β- d -galactoside 7- O -β- d -glucoside ( 6 ), kaempferol 3-O-β-glucopyranosyl(1 → 2)-β-glucopyranoside-7-O-α-rhamnopyranoside ( 7 ), pinoresinol 4′′- O - β - d -glucopyranoside ( 8 ), (7 R ,8 S ,7′ S ,8′ R )-4,9,4′,7′-tetrahydroxy-3,3′-dimethoxy-7,9′-epoxy-lignan-4- O -β- d -glucopyranoside ( 9 ), and (7 S ,8 R ,7′ S ,8′ S )-4,9,4′,7′-tetrahydroxy-3,3′-dimethoxy-7,9′-epoxylignan-4- O -β- d -glucopyranoside ( 10 ). Their structures were elucidated by extensive spectroscopic methods, including 1D and 2D NMR and MS spectra. Compounds 2 - 4 and 6 - 10 were shown to have modest anti-inflammatory effects through inhibition of NO production in LPS-stimulated BV cells.

Two new naphtoquinones (smenocerones A and B, 1 and 2) and four known sesquiterpene cyclopentenones (dactylospongenones A-D, 3-6) were isolated from sponge Smenospongia cerebriformis living in the Eastern Sea of Vietnam. Their chemical structures were determined by high resolution electrospray ionization (HR-ESI)-MS, NMR spectroscopic analysis, and in comparison with the reported data. The chiroptical properties of compounds 3-6 were examined by experiment and theoretical calculation of circular dichroism (CD) spectra to prove their absolute configurations. Compound 2 significantly exhibited cytotoxic activity towards lung carcinoma (LU-1), hepatocellular carcinoma (HepG-2), promyelocytic leukemia (HL-60), breast carcinoma (MCF-7), and melanoma (SK-Mel-2) human cancer cells with IC50 values of 5.5±0.8, 3.2±0.2, 4.0±0.7, 4.1±0.8, and 5.7±1.1 µg/mL, respectively.

The title compound is the product of the Chichibabin domino reaction of 1,8-bis­(2-acetyl­phen­oxy)-3,6-dioxa­octane with 4-methyl­benzaldehyde and ammonium acetate in acetic acid. It is of inter­est with respect to its potential anti­cancer activity. The compound has a bowl-like conformation comprising a fused tetra­cyclic system containing a 4-aryl­pyridine fragment, two benzene rings and an aza-17-crown-5 ether moiety., The title compound, C30H29NO4, is a tetra­cyclic system containing a 4-aryl­pyridine fragment, two benzene rings and an aza-17-crown-5 ether moiety, in a bowl-like arrangement. The pyridine ring is inclined to the 4-methyl­phenyl ring by 26.64 (6)°, and by 57.43 (6) and 56.81 (6)° to the benzene rings. The benzene rings are inclined to one another by 88.32 (6)°. In the crystal, mol­ecules are linked by pairs of C—H⋯N hydrogen bonds, forming inversion dimers with an R 2 2(14) ring motif. The dimers are linked via a number of C—H⋯π inter­actions, forming a three-dimensional architecture.

1-(2-Acetyl-11-meth­oxy-5,6-di­hydro­[1,3]dioxolo[4,5-g]pyrrolo­[2,1-a]isoquinolin-1-yl)propan-2-one, the product of a domino reaction between cotarnine chloride and acetyl­acetylene catalysed by copper(I) iodide, was studied by X-ray diffraction., The title compound, C19H19NO5, (I), is the product of a domino reaction between cotarnine chloride and acetyl­acetylene catalysed by copper(I) iodide. The mol­ecule of (I) comprises a fused tetra­cyclic system containing two terminal five-membered rings (pyrrole and 1,3-dioxole) and two central six-membered rings (di­hydro­pyridine and benzene). The five-membered 1,3-dioxole ring has an envelope conformation and the central six-membered di­hydro­pyridine ring adopts a twist-boat conformation. The acyl substituent is almost coplanar with the pyrrole ring, whereas the meth­oxy substituent is twisted by 27.93 (16)° relative to the benzene ring. The 2-oxopropan-1-yl substituent is roughly perpendicular to the pyrrole ring. In the crystal, mol­ecules are stacked along the a-axis direction; the stacks are linked by weak C—H⋯O hydrogen bonds into puckered layers lying parallel to (001).

Using various chromatographic methods, two new alkaloids, antidesoic acids A (1) and B (2) along with fourteen known compounds (3-16) were isolated from the leaves of Antidesma ghaesembilla Gaertn. Their chemical structures were elucidated by physical and chemical methods. All the isolated compounds were evaluated for their inhibitory activity on LPS-stimulated nitric oxide (NO) production in BV2 cells and RAW 264.7 macrophages. Bisflavone 8 significantly inhibited LPS-stimulated NO production in BV2 cells and RAW 264.7 macrophages with IC50 values of 5.4 and 8.0 μM, respectively. Compounds 1–3, 7, 10, 12, 14, and 16 showed moderate inhibitory activities with IC50 values ranging from 11.7 to 77.4 μM.

A simple two-level system is introduced to demonstrate the existence of the intermolecular mechanism of the appearance/disappearance of multiple maxima in molecular dynamic susceptibility at low temperature. With minimum two relaxation processes, quantum tunneling induced by the nuclear spin bath and the direct process due to the spin-phonon interaction, we prove that the existence of a sufficiently wide dipolar field distribution in the experimental sample is the main cause of this phenomenon in zero or weak applied dc field. The correlations between the phenomenon and the applied dc field, temperature, or magnetic dilution of the sample are also investigated. Application to several experimental systems has shown a good agreement between the proposed theory and experiments. Cases with more complex multiplet spectrum, more relaxation processes,and possibility of more maxima in the molecular dynamic susceptibility are discussed., 13 pages, 9 figures, 1 Supplementary Material

Two new lignans (7S,7'R,8S,8'R)-3,3'-dimethoxy-7,7'-epoxylignan-4,4',9-triol 4-O-β-D-glucopyranoside (1) and 9-O-formylaviculin (2) together with other thirteen known secondary metabolites were isolated from the leaves of Antidesma hainanensis. Their chemical structures were determined using NMR, electrospray ionization (ESI)-MS, circular dichroism (CD) spectroscopic methods, and as well as by comparison with those reported in the literature. Neuro-inflammatory activity of isolated compounds was evaluated by their inhibition on nitric oxide (NO) production in activated BV2 microglial cells. At concentration of 40 µM, compounds 1-3, 5, 7, 8, 9, 14, and 15 exhibited inhibitory effects over 50%, suggesting that they could be potential candidate drugs for the cure of neuro-inflammation. In addition, compounds 1, 8, 14, and 15 significantly inhibited 16.23, 27.76, 21.23, and 29.44% NO production at diluted concentration as low as 2.5 µM.

The pyridinocrownophane derivatives containing 2,6-diaryl-γ-arylpyridine subunit and the aza-14-crown-4 ether ring have been exhibit high cytotoxicity on several tumor cell lines such as Hep- G2, MCF7, FL, RD, Lu. This study continues to develop method of synthesis of new γ-(fur-2-yl)pyridinoaza-14-crown-4-ether (2), γ-(naphthalen-1-yl)pyridinoaza-14-crown-4-ether (3), γ-(thien-2-yl)pyridinoaza-17-crown-5-ether (4) and γ-(2-pyridino)pyridinoaza-17-crown-5-ether (5) based on the 1,5-bis- (2-acetylphenoxy) -3- -oxapentane (1a) and 1,8-bis- (2-acetylphenoxy) -36-dioxaoctane (1b). The structure of these derivatives has determined by 1 H NMR, HPLC-MS.

We study the spin-phonon relaxation rate of both Kramers and non-Kramers molecular magnets in strongly diluted samples at low temperature. Using the "rotational" contribution to the spin-phonon Hamiltonian, universal formulae for the relaxation rate are obtained. Intriguingly, these formulae are all entirely expressed via measurable or \emph{ab initio} computable physical quantities. Moreover, they are also independent of the energy gaps to excited states involved in the relaxation process. These obtained expressions for direct and Raman processes offer an easy way to determine the lowest limit of the spin-phonon relaxation of any spin system based on magnetic properties of the ground doublet only. In addition, some intriguing properties of Raman process are also found. Particularly, Raman process in Kramers system is found dependent on the magnetic field's orientation but independent of its magnitude, meanwhile the same process in non-Kramers system is significantly reduced out of resonance, i.e. for an applied external field. Interestingly, Raman process is demonstrated to vary as $T^{9}$ for both systems. Application of the theory to a recently investigated cobalt(II) complex shows that it can provide a reasonably good description for the relaxation. Based on these findings, a strategy in developing efficient single-molecule magnets by enhancing the mechanical rigidity of the molecular unit is proposed., 24 pages, 5 figures

Datura metel L. (Solanaceae) is an annual herb that has been widely used in the traditional medicine for the treatment of coughs, bronchial asthma, and rheumatism. Chemical investigation of an acidic methanol extract of the whole plants of D. metel resulted in the isolation of five new steroidal saponins ( 1 – 3 , 5 , and 6 ), named metelosides A-E, and four known compounds ( 4 , 7 – 9 ). Their structures were elucidated by extensive spectroscopic methods, including 1D and 2D NMR and MS spectra. The structures of metelosides A and B were found to be unusual among the reported spirostane-type steroidal saponins due to the presence of the acetamide groups in the molecules. Compounds 2 , 4 , 5 , and 6 were shown to be cytotoxic against three cancer cell lines, including HepG2, MCF-7, and SK-Mel-2 cells. Furthermore, compounds 3 , 4 , and 7 exhibited modest anti-inflammatory effects through inhibition of NO production in LPS-stimulated BV cells.

Using various chromatographic methods, five new sesquiterpene derivatives named smenohaimiens A-E (1-5) and five known, 19-hydroxy-polyfibrospongol B (6), ilimaquinone (7), dictyoceratin C (8), polyfibrospongol A (9), and polyfibrospongol B (10) were isolated from the marine sponge Smenospongia cerebriformis Duchassaing & Michelotti, 1864. Their structures were assigned by 1D, 2D NMR spectroscopic analysis, HR ESI MS, and calculations of the electron circular dichroism spectra. All compounds were evaluated for the inhibitory activity against NO production in lipopolysaccharide-stimulated in BV2 microglia cells. As the results, compound 7 significantly inhibited NO production with the IC50 value of 10.40±1.28µM. The remaining compounds showed moderate inhibitory NO production activities with IC50 values ranging from 24.37 to 30.43µM.

Inhibitory effects of NO production in RAW 264.7 macrophages guided the isolation of nine prenylated isoflavones, including a new cudraisoflavone L (1) and eight known metabolites furowanin B (2), erysubin A (3), wighteone (4), lupalbigenin (5), laburnetin (6), isolupalbigenin (7), 6,8-diprenylorobol (8), millewanin H (9) from the leaves of Cudrania tricuspidata. At the concentration of 10 μM, compounds 1, 2, and 4 significantly inhibited NO production with the inhibitory values of 72.5 ± 2.4, 66.9 ± 1.8, and 55.4 ± 2.7%, respectively. In addition, all of isolated compounds 1–9 showed promising cytotoxic effects toward HL-60 cells (IC50 4.3 ± 0.7 to 18.0 ± 1.7 μM).

Multiple relaxation times detected in the ac magnetic susceptibility of several single-molecule magnets have been always assigned to extrinsic factors, such as nonequivalent magnetic centers or effects of intermolecular interactions in the crystal. By solving quantum relaxation equations, we prove that the observed multiple relaxation times can be of intramolecular origin and can show up even in single-ion metal complexes. For the latter a remarkably good description of the coexistent two relaxation times is demonstrated on several experimental examples. This proves the relevance of the intramolecular mechanism of multiple relaxation times in such systems, which is even easier justified in polynuclear magnetic complexes., Comment: 5 pages, 5 figures

Two new sesquiterpenes and one new bis-sesquiterpene, named dysinidins C-E (1–3) along with three known sterols, dysideasterol F, 9α,11α-epoxycholest-7-en-3β,5α,6α-triol, and 9α,11α-epoxycholest-7-en-3β,5α,6α,19-tetrol 6-acetate (4–6) were isolated from the Vietnamese marine sponge Dysidea fragilis (Montagu, 1814). Their structures were determined by 1D- and 2D-NMR spectroscopies and HR-ESI-MS, as well as by comparison with reported literature data. Compounds 4–6 were found to inhibit eight human cancer cell lines (KB, LU-1, HL-60, LNCaP, SK-Mel-2, HepG-2, MCF-7, and PC-3), with IC50 values ranging from 7.3 to 31.5 μM.

Five new compounds, named ancistronaphtosides A and B (1 and 2), anciscochine (3), anciscochine 6-O-β-d-glucopyranoside (4), and 4'-methoxy-5-epi-ancistecrorine A1 (5), together with tortoside A (6) and 4-hydroxy-2-methoxyphenyl-6-O-syringoyl-β-d-glucopyranoside (7) were isolated from the methanolic extract of Ancistrocladus cochinchinensis. Their chemical structures were established using HR-ESI-MS, NMR spectroscopic, and chiroptical methods. Compound 5 significantly exhibited anti-proliferation against HL-60, LU-1, and SK-MEL-2 cells with IC50 values of 5.0±1.2, 6.5±1.6, and 6.8±2.0μg/mL, respectively.

The crystal structure of a product of the Petrenko–Kritchenko condensation of N-propyl­piperidone with 1,5-bis­(2-formyl­phen­oxy)-3-oxa­pentane and ammonium acetate was studied by X-ray diffraction, The title compound, C26H32N2O4(M)·C2H4O2, (I), is the product of the Petrenko–Kritchenko condensation of N-propyl­piperidinone with 1,5-bis­(2-formyl­phen­oxy)-3-oxa­pentane and ammonium acetate. In M, the aza-14-crown-3-ether ring adopts a bowl conformation, with the configuration of the C—O—C—C —O—C—C—O—C polyether chain being t–g (−)–t–t–g (+)–t (t = trans, 180°; g = gauche, ±60°). The dihedral angle between the planes of the benzene rings fused to the aza-14-crown-4-ether moiety is 62.75 (5)°. The central piperidinone ring has a boat conformation, whereas the terminal piperidinone ring adopts a chair conformation. The boat conformation of the central piperidinone ring is supported by the bifurcated intra­molecular N—H⋯O hydrogen bond. In the crystal, each solvent mol­ecule is linked to mol­ecule M via strong O—H⋯N hydrogen bonding, forming hydrogen-bonded pairs of mol­ecules, which further inter­act through weak C—H⋯O hydrogen bonds, forming layers parallel to the ac plane.

By using various chromatographic methods, two sterols and one flavone, vernoniamygda A (1), vernoniamygda B (2), and luteolin (3) were isolated from the methanol extract of the leaves of Vernonia amygdalina. Their structures were determined using 1D, 2D-NMR and ESI-MS analysis as well as by comparison with the reported data. Compounds 1 and 2 were reported from natural for the first time.

Using various chromatographic methods, five new steroidal saponins named taccavietnamosides A-E (1-5) and three known, (24S,25R)-spirost-5-en-3β,24-diol 3-O-α-l-rhamnopyranosyl-(1→2)-[α-l-rhamnopyranosyl-(1→3)]-β-d-glucopyranoside (6), (24S,25R)-spirost-5-en-3β,24-diol 3-O-α-l-rhamnopyranosyl-(1→2)-[β-d-glucopyranosyl-(1→4)-α-l-rhamnopyranosyl-(1→3)]-β-d-glucopyranoside (7), and chantrieroside A (8) were isolated from the rhizomes of Tacca vietnamensis Thin et Hoat. Their chemical structures were elucidated by physical and chemical methods. All compounds were evaluated for the inhibitory activities of nitric oxide production in LPS-stimulated RAW 264.7 macrophages and BV2 cells. As the results, compounds 3-5 showed moderate inhibition on NO production in LPS-stimulated BV2 cells and RAW 264.7 macrophages with the IC50 values ranging from 37.0 to 60.7μM.

A methanol extract of the soft coral Sinularia microspiculata revealed five sterols, including two new compounds. Using combined chromatographic and spectroscopic experiments, the new compounds were found to be 7-oxogorgosterol (1) and 16α-hydroxysarcosterol (2). Their structures were determined on the basis of spectroscopic data (1H and 13C NMR, HSQC, HMBC, 1H-1H COSY, NOESY, and FT-ICR-MS) and by comparing obtained results to the values indicated in previous studies. Among the isolated compounds, 3 showed weak cytotoxic effects against HL-60 (IC50 = 89.02 ± 9.93 μM) cell line, whereas 5 was weakly active against HL-60 (IC50 = 82.80 ± 13.65 μM) and SK-Mel2 (IC50 = 72.32 ± 1.30 μM) cell lines.

Using various chromatography methods, a saponin, ginsenoside Rg1 (1), and three phenolic glycosides, tortoside A (2), phlorizin (3), and 4-hydroxy-2-methoxyphenyl-6-O-syringyl-b-D-glucopyranoside (4) were isolated from the water-soluble fraction of Ancistrocladus cochinchinensis. Their structures were elucidated by 1D- and 2D-NMR spectroscopic analyses and comparison with those reported in the literature. Compound 1 was reported from A. cochinchinensis for the first time.

One new isoflavane, 7,4′-dihydroxy-isoflavanquinone (1), together with ten known compounds (2–11) were isolated from the bark of Dalbergia oliveri Prain. The structures of compounds were determined on the basis of extensive spectroscopic methods, including 1D and 2D NMR and CD spectroscopic data. Using a cell proliferation assay, the isolated compounds were evaluated for their proliferation effects on hair growth. (3 R)-5’-Methoxyvestitol (2) and (6a R,11a R)-3,8-dihydroxy-9-methoxypterocarpan (10) significantly increased the proliferation of immortalized dermal papilla cells (iDPC).

Two new resorcinol derivatives, named agrimopilosides A and B (1 and 2), along with two known compounds, (2 S, 3 S)-aromadendrin 3-O-β-D-glucopyranoside (3), (2 S, 3 S)-glucodistylin (4) were isolated from the aerial parts of Agrimonia pilosa. Their chemical structures were determined by mean of HRMS, NMR, CD spectra, and as well as by comparison with the reported data. At concentration of 20 μM, compounds 1–4 modestly inhibited NO production in LPS-stimulated RAW264.7 cells, with the inhibitory rates in the range of 9.55–33.73%. None of them showed cytotoxicity toward HepG2, MCF-7, and SK-LU-1 human cancer cells by MTT assay.

Five new oleanane-type saponins, hirsutosides A-E, were isolated from the leaves of Glochidion hirsutum (Roxb.) Voigt. Their structures were elucidated as 21β-benzoyloxy-3β,16β,23,28-tetrahydroxyolean-12-ene 3-O-β-D-glucopyranoside (1), 21β-benzoyloxy-3β,16β,23,28-tetrahydroxyolean-12-ene 3-O-β-D-glucopyranosyl-(1→3)-β-D-glucopyranoside (2), 21β-benzoyloxy-3β,16β,23,28-tetrahydroxyolean-12-ene 3-O-6-acetyl-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranoside (3), 21β-benzoyloxy-3β,16β,23,28-tetrahydroxyolean-12-ene 3-O-β-D-glucopyranosyl-(1→3)-α-L-arabinopyranoside (4), and 21β-benzoyloxy-3β,16β,23-trihydroxyolean-12-ene-28-al 3-O-β-D-glucopyranosyl-(1→3)-α-L-arabinopyranoside (5). All isolated compounds were evaluated for cytotoxic activities on four human cancer cell lines, HepG-2, A-549, MCF-7, and SW-626 using the SRB assay. Compounds 1, 2, 4, and 5 showed significant cytotoxic activities against all human cancer cell lines with IC50 values ranging from 3.4 to 10.2 μM. Compound 3 containing acetyl group at glc C(6″) exhibited weak cytotoxic activity with IC50 values ranging from 47.0 to 54.4 μM. This article is protected by copyright. All rights reserved.

Using various chromatographic methods, one new sesquiterpene quinone named smenohaimien F (1) and five known, neodactyloquinone (2), dactyloquinone C (3), dactyloquinone D (4), isoamijiol (5), and amijiol (6), were isolated from the marine sponge Smenospongia cerebriformis Duchassaing & Michelotti, 1864. Their structures were elucidated by 1D-, 2D-NMR spectroscopic analysis, HR-ESI-MS, and by comparing with the NMR data reported in the literature. The cytotoxic activities of the all compounds were evaluated on five human cancer cell lines, LU-1, HL-60, SK-Mel-2, HepG-2, and MCF-7. Compound 4 was found to exhibit significant cytotoxic activities on all tested human cancer cell lines with IC50 values ranging from 0.7 to 1.6 μg/mL.

Two new phenolic glycosides, physangulosides A and B (1 and 2), were isolated from the whole plant of Physalis angulata. Their chemical structures were determined by mean of HR-ESI-MS, 1D, and 2D-NMR spectra. Both of the compounds showed weak protection against hydrogen peroxide induced hepatocytes damage.

Using combined chromatographic methods, two new compounds, 6β,9β:9,13-diepoxymegastig-4-en-3β-ol (1), 5α,6α-epoxy D:C-friedoolean-8-en-3β-ol (2) were isolated from the methanol extract of the leaves of Glochidion obliquum Decne. Their structures were elucidated by 1D- and 2D-NMR spectra and in comparison with those reported in the literature.