Abstract In the presence of catalytic amounts elemental sulfur, dibenzyl disulfide/DMSO was found to be an excellent thiobenzoylating agent amines provide a wide range thioamides. The reaction becomes autocatalytic when anilines substituted by o ‐cyclizable group were used as nucleophile, leading corresponding 2‐aryl aza heterocycles. magnified image

Abstract A straightforward access to 2‐amino‐3‐arylthiophenes has been developed via one‐pot two‐step three‐component reaction of arylacetonitriles, chalcones and elemental sulfur. The first step consists a DBU‐catalyzed formation Michael adduct between arylacetonitriles chalcones. second is cascade DABCO‐catalyzed sulfuration the with sulfur followed by an oxidative cyclization afford thiophenes. Compared Gewald reactions related transformations which are limited in acetonitriles bearing...

As frequently encountered byproducts of isocyanate chemistry, hydrogen sulfide and related sulfur containing compounds should be treated in a safe way to lower their adverse health environmental effects, especially large scale syntheses. proof concept, we report herein an example situ recycling byproduct reductant the synthesis bioactive 2-aminobenzoxazoles 3. Using Fe/S catalytic system, this heterocyclic scaffold could obtained from o-nitrophenols 1 with isothiocyates 2 via direct redox...

ABSTRACT The present study aims to assess surface water quality (WQI), wastewater (WWQI), and the presence of toxic chemicals, including metals endocrine‐disrupting compounds (EDCs), in Saigon River basin. A total 27 samples from nine locations basin 30 10 industrial parks were collected 2023. In addition, Pearson correlation analysis, principal component analysis (PCA), cluster (CA) employed investigate relationships potential sources parameters, heavy metals, EDCs wastewater. Water Quality...

The S₈/DMSO combination was found to be particularly effective promote oxidative coupling of methylhetarenes with amines synthesize thioamides/bis-aza-heterocycles.

Abstract While elemental sulfur has been largely used as oxidant or sulfurating agent, its role a catalyst not developed. We report here catalytic activity in the oxidative condensation of o ‐phenylenediamines with acetophenones DMSO to provide quinoxalines. The method was also extended α‐tetralones, propiophenones (R=Me) well higher homologues (R=Et, n ‐Pr) place acetophenones, leading wide range naphthoquinoxalines and 3‐substituted 2‐arylquinoxalines. magnified image

The oxidative amination of alkynes typically requires transition metal catalysts and strong oxidants. Herein, we alternatively utilize DABCO as a sulfur-activating catalyst to achieve the sulfurative 1,2-diamination phenylacetylenes with elemental sulfur o-phenylenediamines. DMSO was found be particularly suitable for use terminal oxidant this three-component process. A mechanistic study has shown that cascade reaction is triggered by addition active species triple bond phenylacetylenes.

Abstract Density functional theory methods were employed to clarify the adsorption/desorption behaviors of thione‐containing mercaptopurine and thioguanine drugs on gold surface using both small Au 6 8 clusters as model reactants. Structural features, thermodynamic parameters, bonding characteristics, electronic properties resulting complexes investigated Perdew–Burke–Ernzerhof (PBE) LC‐BLYP functionals along with correlation‐consistent basis sets, namely cc‐pVDZ‐PP for cc‐pVTZ non‐metals....

In this study, TiO2 nanowires on nanotubes arrays (TNWs/TNAs) and Au-decorated TNWs/TNAs nanostructures are designed fabricated as a new type of photoanode for photoelectrochemical (PEC) water splitting. The were Ti folds by anodization using an aqueous NH4F/ethylene glycol solution, while Au nanoparticles (NPs) nanorods (NRs) synthesized Turkevich methods. We studied the crystal structure, morphology, PEC activity four types nanomaterial photoanodes, including TNWs/TNAs, NPs- NRs-TNWs/TNAs,...

Sodium sulfide trihydrate promoted-redox condensation of o -nitroanilines with α-tetralones to benzo[ a ]phenazines.

A cost-effective, practical, straightforward and scalable synthesis of α-pyrones via base- sulfur-promoted annulation phenylacetates chalcones is reported.

Abstract Lichens are a promising source of good anticancer agents. However the study on their bioactivities remains limited, especially in Vietnam. In this study, three extracts lichen Usnea undulata Stirt. including n ‐hexane, acetone and methanol were investigated for cytotoxic activity two human cancer cell lines (MCF‐7, NCI‐H460) normal fibroblasts by sulforhodamine B (SRB) assay . The results showed that n‐ hexane extract exhibited highest inhibition with IC 50 5.26±0.13 μg/mL MCF‐7...

Abstract Dalbergia species heartwood, widely used in traditional medicine to treat various cardiovascular diseases, might represent a rich source of vasoactive agents. In Vietnam, tonkinensis is an endemic tree. Therefore, the aim present work was investigate vascular activity R-(−)-3′-hydroxy-2,4,5-trimethoxydalbergiquinol isolated from heartwood D. and provide circular dichroism features its R absolute configuration. The effects were assessed on vitro mechanical rat aorta rings, under...

Redox condensation of <italic>o</italic>-nitrophenols with acetophenones/methylquinolines using a biomimetic Fe/S catalyst under mild conditions.

Machilus thunbergii has a history of traditional applications including treating dyspepsia, apoplexy, headaches, abdominal pain, distension, and leg edema [1]. It is also employed for alleviating allergies, inflammation, pain relief, promoting blood circulation, addressing costal chondritis, sinusitis [2]. Research into the chemical composition M. revealed presence lignans, flavonoids, lactones, essential oils [1,[3], [4], [5]. While some investigations have explored inhibitory effects...

Nanocomposites of TiO2 Degussa P25 nanoparticles/activated carbon (TiO2/AC ) were prepared at various mass ratios (4:1), (3:2), (2:3), and (1:4) by a facile process. The effects TiO2/AC on the structural, morphological, photocatalytic properties systematically studied in comparison with bare AC. nanoparticles exhibited dominant anatase minor rutile phases, crystallite size approximately 21 nm; while AC had XRD peaks graphite carbon, 49 nm. composites tight decoration micron-/submicron...

The development of nanocomposite photocatalysts with high photocatalytic activity, cost-effectiveness, a simple preparation process, and scalability for practical applications is great interest. In this study, nanocomposites TiO2 Degussa P25 nanoparticles/activated carbon (TiO2/AC) were prepared at various mass ratios (4:1), (3:2), (2:3), (1:4) by facile process involving manual mechanical pounding, ultrasonic-assisted mixing in an ethanol solution, paper filtration, mild thermal annealing....

The sulfur–DMSO couple was found to promote the coupling of active methylhetarenes with amines yield amides under heating conditions. When 2-methylquinoline used as methylhetarene component, reaction could be catalyzed by Fe, Co and Ni salts.

Abstract The medicinal plant Euphorbia hirta L. has been widely acknowledged for use in traditional medicine of Vietnam. whole plants E. are commonly applied to cure a wide range diseases, especially gastrointestinal disorders, skin problems, and respiratory system. This study focused on chemical composition the plant. investigation n -hexane ethyl acetate extracts this species led isolation structural determination taraxerol ( 1 ), campesterol 2 astragalin 3 hymenoxin 4 luteolin-7- O - β...

Despite diphtheria immunization are to apply an effective primary in childhood and maintain immunity throughout life. Cases of have been reported Viet Nam recent years. The aim this study was evaluate the seroprevalence IgG antibodies toxoid among healthy person population Kon Tum, Nam.Blood samples were obtained from 2225 persons aged 2-98 years collected 2019 2020. Samples tested for by commercial Anti-Diphtheria Toxoid Enzyme-Linked Immunosorbent Assay (ELISA).An antibody level <0.01...

Mycosporine-like amino acids (MAAs) were quantified in fresh and preserved material of the chlorolichen Dermatocarponluridum var. luridum (Verrucariaceae/Ascomycota). The analyzed samples represented a time-series over 150 years. An HPLC coupled with diode array detector (HPLC-DAD) hydrophilic interaction liquid chromatography (HILIC) mode method was developed validated for quantitative determination MAAs. We found evidence substance specific differences quality preservation two MAAs...

Invivo Antidiabetic evaluation of Neem leaf extract in alloxan induced ratsShravan Kumar Dholi, Ramakrishna Raparla, Santhosh Mankala, Kannappan Nagappan

A phytochemical investigation was conducted on a foliose lichen, Parmotrema tinctorum (Nyl.) Hale, collected in Lam Dong province, Vietnam. Colour reactions for identification of lichen substances (+K deep yellow, +C red, +KC + P pale yellow) suggested the presence atranorin, lecanoric acid, quinones, depsides, and xanthones containing two free hydroxyl groups meta-position. Chemical constituent study led to isolation six compounds, including atranol (1), methyl haematomate (2),...

The study aimed to explore knowledge, attitudes and behaviors of premarital sex its associated factors among bedsit-living students. A community-based cross-sectional was conducted in Hue city, Vietnam 2015. Multi-stage cluster sampling used recruit Data were collected by using a self-administered questionnaire at participant&rsquo;s room. total 730 students (men/women: 44.2%/55.8%, mean age: 20.9 years) enrolled. Prevalence 11.9% with an average age first sexual intercourse 19.8 &plusmn;...