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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.

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

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.

One new lignan, trichobenzolignan (1), and seven known compounds, ligballinol (2), (-)-pinoresinol (3), ehletianol C (4), luteolin 7-O-β-D-glucopyranoside (5), chrysoeriol-7- O-β-D-glucopyranoside (6), 10α-cucurbita-5,24-dien-3β-ol (7), and arvenin I (8). Their structures were established on the basis of spectral and chemical evidence, which were in agreement with those reported in literature. The cytotoxic activities of these compounds were evaluated on four cancer cell lines such as A-549 (human lung cancer), HT-29 (human colon adenocarcinoma), OVCAR (human ovarian carcinoma), and MCF-7 (human breast cancer). As the results, compound 7 showed significant activity on HT-29 and OVCAR cancer cell lines with IC50 of 4.1 and 6.5 µM, respectively. Compounds 1, 5, 6, and 8 exhibited moderate activities in all cancer cell lines with IC50 ranging from 11.3 to 42.8 µM.

The synthesis of benzosilanochromenoimidazopyridines was accomplished by a domino reaction of 5,5-dimethyl-10-oxo- and 10-hydroxy-10-allyldihydrobenzosilanopyridinium N-cyanomethyl salts with salicyl- and 5-bromosalicylaldehydes. It was found that in the case of the 10-allyl-10-hydroxy-dihydrobenzosilanopyridinium salts the reaction occurred at both α-positions of the pyridine fragment to form a mixture of the isomeric benzosilano[3,2-c]- and benzosilano[2,3-d]chromenoimidazo-pyridines.

Bioassay-guided fractionation based on the anti-inflammatory activity of a methanol extract of Ficus microcarpa leaves led to the isolation of seven galactolipids: 2(S)-3-O-octadeca-9Z,12Z,15Z-trienoylglyceryl-O-β-D-galactopyranoside (1), (2S)-2,3-O-dioctadeca-9Z,12Z,15Z-trienoylglyceryl-O-β-D-galactopyranoside (2), (2S)-2,3-O-dioctadeca-9Z,12Z-dienoylglyceryl-O-β-D-galactopyranoside (3), (2S)-3-O-octadeca-9Z,12Z,15Z-trienoylglyceryl-6'-O-(α-D-galactopyranosyl)-β-D-galactopyranoside (4), (2S)-2,3-O-dioctadeca-9Z,12Z,15Z-trienoylglyceryl-6'-O-(α-D-galactopyranosyl)-β-D-galactopyranoside (5), gingerglycolipid B (6), and (2S)-2,3-O-dioctadeca-9Z,12Z-dienoylglyceryl-6'-O-(α-D-galactopyranosyl)-β-D-galactopyranoside (7). Their chemical structures were elucidated by mass, 1D-, and 2D-NMR spectroscopic methods as well as chemical methods. The antiinflammatory effect of these compounds on TNF-α induced IL-8 secretion in the HT-29 cell line was evaluated. All above galactolipids showed significant inhibition ranging 40% at a concentration of 50 μM. The results suggest that galactolipids from the leaves of F. microcarpa may be used as potent anti-inflammatory agents.

Eight compounds were isolated from methanol extract of Plantago major L. leaves and investigated for their ability to inhibit angiotensin I-converting enzyme activity. Among them, compound 1 showed the most potent inhibition with rate of 28.06 ± 0.21% at a concentration of 100 μM. Compounds 2 and 8 exhibited weak activities. These results suggest that compound 1 might contribute to the ability of P. major to inhibit the activity of angiotensin I- converting enzyme.

4,8a-Diphenyl-substituted 2-(2-propoxy)perhydro[1,3,2]dioxaborinino[5.4-c]pyridine was obtained by the condensation of 4-hydroxy-3-(α-hydroxybenzyl)-1-methyl-4-phenylpiperidine with triisopropyl borate, and its 2-hydroxysubstituted analog in the presence of water. 1-Methyl-4,8a-diphenyl-perhidro[1,3]dioxano[5,4-c]pyridine was synthesized by the reaction of the same piperidol with formaldehyde. A comparative study of the molecular structures of the three products was carried out by X-ray crystallography.

Aryl-N-methyl-and aryl-N-benzyl-B-substituted 4,8a-diphenylperhydro[1,3,2]dioxaborinino[5,4-c]pyridines, which are representatives of a new class of bicyclic compounds containing four heteroatoms, were synthesized from N-methyl-and N-benzyl-3-(α-hydroxybenzyl)-4-phenyl-γ-piperidols by cyclocondensation with arylboronic acids. The 1H NMR and mass spectra of these compounds were examined as well as mass spectra of previously obtained analogs.

To continue exploration of structure activity relationship of novel 1-(indoline-5-sulfonyl)-4-phenylimidazolidinones (1) reported as anticancer agent with broad spectrum, three 1-(arylsulfonyl)-4-vinylimidazolidinones (2) were synthesized from methyl serinate (3) in 8 steps. Reaction of intermediate 2-phenoxycarbonylaminobut-3-enyl p-toluenesulfonate (10) with arylsulfonamide in the presence of potassium carbonate produced corresponding 2 and N-(4-vinyloxazolidin-2-yl)arylsulfonamide 11 in approximately equal ratio. This reaction is believed to undergo through urea intermediate 16 as shown in scheme 3. 1-Arylsufonyl-4-vinylimidazolidinones 2 show much reduced activity against human colon carcinoma (Colo205), human chronic myelogenous leukemia (K562), and human ovarian adenocarcinoma (SK-OV-3) and compatible activity against human lung carcinoma (A549) compared to 1. Therefore phenyl at 4-position should be the optimum planar motif for the activity of 1.

1,4-bis(8,11,14-trioxa-25-azatetracyclopentacos-23-yl)benzene, terephthalaldehyde conden-sation with 1,5-bis(2-acetylphenoxy)-3-oxapentane and ammonia. In the publications [1-6] methods have been reported for the preparation of azacrown ethers containing hydrogenated derivatives of various heterocycles (e.g. piperidine [1, 2], azabicycloalkane [3], tetrahydropyran [4], bispyridine [5], or perhydrotriazine [6]) in the macrocycle. Continuing our work on developing novel methods for the preparation of azacrown ethers we have studied the possibility of constructing a heterocyclic system which includes two (pyrido)azacrown ether fragments separated by a benzene spacer. With the aim of preparing similar ditopic macromolecues we have carried out a three-component condensation of the 1,5-bis(2-acetylphenoxy)-3-oxapentane (

azafluoren-9-ones, benzaldehyde, azafluoren-9-one N-oxides, manganese dioxide, Baeyer–Villiger reaction, oxidation. Oxidative rearrangement of alicyclic ketones to form lactones (the Baeyer–Villiger reaction) occurs under the action of hydrogen peroxide, peracids [1-4], and also less hazardous modified oxidative systems such as, for example, oxygen–benzaldehyde–manganese dioxide [5]. In this work, when using this modified system for oxidation of 9-oxo-1-azafluorene (