Adsorption mechanism of aqueous Cr(vi) by Vietnamese corncob biochar: a spectroscopic study.

Cr(vi) is highly toxic and carcinogenic, posing significant threats to health and ecosystems. This study utilizes solid waste from corncobs to synthesize biochar (CCBC) for the removal of Cr(vi) from water. The most effective Cr(vi) removal was achieved at pH 2.

Computational discovery of tripeptide inhibitors targeting monkeypox virus A42R profilin-like protein.

Monkeypox is an infectious disease caused by the monkeypox virus (MPXV), a member of the Orthopoxvirus genus closely related to smallpox. The structure of the A42R profilin-like protein is the first and only available structure among MPXV proteins. Biochemical studies of A42R were conducted in the 1990s and later work also analyzed the protein's function in viral replication in cells.

MedChemExpress compounds prevent neuraminidase N1 physics- and knowledge-based methods.

Influenza A viruses spread out worldwide, causing several global concerns. Hence, discovering neuraminidase inhibitors to prevent the influenza A virus is of great interest. In this work, a machine learning model was employed to evaluate the ligand-binding affinity of 10 000 compounds from the MedChemExpress (MCE) database for inhibiting neuraminidase.

Comtrifosides A and B, two new triterpenoid saponins from the leaves of .

The phytochemical composition of the leaves was studied for the first time. Two new triterpenoid saponins, named comtrifoside A () and comtrifoside B (), together with two other saponins () were purified by variously chromatographic techniques. For the first time, compound was informed from the genus, as well as all of the isolated compounds () were reported from .

Two New Benzoquinone Derivatives from Vietnamese Knema globularia Stems.

The chemical investigation of the stems of Knema globularia led to the isolation of two new benzoquinones derivatives, embenones A and B (1 and 2), along with three known compounds (3-5). The structures of the isolated compounds were determined using spectroscopic techniques, including HRESIMS, 1D and 2D NMR, in conjunction with comparison to existing literature data. Compounds 1 and 2 represent new carbon skeletons in nature.

Antimicrobial sesquiterpenes from the cultured mycobiont against methicillin-resistant isolated from Vietnamese street foods.

Traditionally, lichen has been used for many purposes, but there remains a lack of understanding regarding the chemical composition and antimicrobial characteristics of , a lichen native to Vietnam. In this study, four sesquiterpenes, diorygmones B-E (1-4), one phenolic compound, 3,5-dihydroxy-4-methoxybenzoic acid (5), and one sterol, β-sitosterol (6), were isolated and structurally elucidated from the cultured mycobiont of the lichen . Additionally, two compounds, stictic acid (7) and norstictic acid (8), were also isolated from the lichen Compounds 2-4 were new compounds.

Bio-guided isolation of alpha-glucosidase inhibitory compounds from Vietnamese liverwort : and studies.

Bio-guided isolation was applied to Vietnamese L. to find alpha-glucosidase inhibition. Fifteen compounds were isolated and structurally determined, including two new compounds, marchatoside (7) and marchanol (8), along with thirteen known compounds: marchantin A (1), isoriccardin C (2), riccardin C (3), marchantin K (4), lunularin (5), 3-(3,4-dimethoxybenzyl)-5,7-dimethoxyphthalide (6), vitexilactone (9), 12-oleanene-3-one (10), 3,11-dioxoursolic acid (11), ursolic acid (12), artemetin (13), kaempferol (14), and quercetin (15).

Bioactive-Guided Phytochemical Investigations, In Vitro and In Silico Alpha-Glucosidase Inhibition of Two Vietnamese Medicinal Plants and .

Little is known about the chemical and biological profiles of and . No previous studies have investigated alpha-glucosidase inhibition using extracts from and . In this paper, bioactive-guided isolation procedures were applied to the plants and based on alpha-glucosidase inhibition.

A New 3-Benzylphthalide from the Moss Erythrodontium julaceum.

From the moss Erythrodontium julaceum Paris growing in Vietnam, julacelide (1), a new 3-benzylphthalide, along with methyl orsellinate (2), ethyl orsellinate (3), 4-O-methylhaematommic acid (4), and zeorin (5), were isolated and structurally elucidated. Their chemical structures were elucidated through extensive 1D and 2D NMR analysis and high-resolution mass spectroscopy as well as through comparisons to the existing literature. Compound 4-O-methylhaematommic acid was a new natural product.

A New Carvotacetone Derivative from the Aerial Part of Sphaeranthus africanus.

Sphaeranthus africanus L. is native in Vietnam. Little is known about α-glucosidase inhibition of Sphaeranthus africanus and its isolated compounds.

Tecomastane, a new megastigmane from the flowers of .

is a tropical plant that is widely used in folk medicine. Little is known about the chemical constituents of flowers of this plant. From flowers of the native plant in Vietnam, 12 compounds were isolated and elucidated, including one new compound tecomastane () and eleven known compounds, (3,5,6,7)-5,6-epoxy-3-hydroxy-7-megastigmane-9-one (), bosciallin (), chakyunglupulin B (), (2,6)-2,6-dimethyloctane-1,8-diol (), cleroindicin F (), rengyoxide (), 3,4-dihydroxybenzoic acid (), methyl 3,4-dihydrobenzoate (), 3,5-dihydroxybenzoic acid (), luteolin (), and indole-3-carboxylic acid ().

Cycloartanes from leaves of growing in Vietnam.

Two new cycloartanes, combretic acid C () and combretanone I (), were isolated from the leaves of Kurz, together with the previously-reported combretic acids A-B ( and ) and combretanone A (). An extensive set of spectroscopic methods were used to elucidate the structures of these compounds. Cytotoxicity against the K562 cancer cell line was evaluated.

A and B: two new oleanane saponins from the aerial parts of .

Two new oleanane saponins, hedyocoronin A and hedyocoronin B (), were isolated from the aerial parts of (Kurz) Craib, Rubiaceae, collected at Da Oai district, Lam Dong province in Vietnam. Their chemical structures were elucidated by HR-MS, 1D and 2D-NMR spectra, along with the comparison with those reported in the literature. Compounds and showed weak cytotoxicity against KB and HeLa-S3 cancer cell lines with IC values of more than 54 µM.

Indicuen, a new hopane from Hale growing in Vietnam.

One new hopane-type triterpene, indicuen (), along with eight known compounds () were isolated from the -hexane extract of the lichen Hale. The chemical structures of isolated compounds were identified by interpretation of their spectroscopic data (1D, 2D NMR and HRESIMS) combined with DFT-NMR chemical shift calculations and subsequent assignment of DP4+ probabilities and by comparison with the literature. Indicuen represents for a rare hopane bearing a 1-carboxyethyl substituent at C-21 in lichens.

Lasibidoupins A and B, two new compounds from the stems of V.S. Dang & Naiki.

From the stems, two new compounds, including one new 9,10-anthraquinone, lasibidoupin A (), and one new 6,7-benzocoumarin, lasibidoupin B (), together with one known compound, 11--methyldamnacanthol () were isolated using chromatographic method. Their structures were determined by extensive HRMS, and NMR assignments. Compound was reported for the first time from this species.

Cycloartane-type triterpenoids from the whole plants of .

One new cycloartane-type triterpenoid, named macrobidoupoic acid A (as an C-24 epimeric mixture, , ), together with three known ones (-), were clarified by different chromatography from the whole plants. Triterpenoids ( & ) were detected for the first time from the genus. Chemical structures of them were illuminated using HR-ESI-MS, and NMR (1 D & 2 D) assessments.

A new oleanane-skeleton triterpene isolated from .

Extensive fractionation of -hexane extract from the dried powdered-trunks of Pierre ex A.Froehner (Rubiaceae) led to the isolation of a new oleanane-skeleton triterpene, coffecanolic acid (), along with three known analogues sumaresinolic acid (), oleanolic acid (), and 3--acetyloleanolic acid (). The chemical structures were elucidated using FT-IR, 1D and 2D NMR and HR-ESI-MS data analysis.

Berectones A and B: Two new rotenoids from the aerial parts of .

Two previously unreported rotenoids, berectones A and B ( and ), along with four known compounds, 3,3',4'-tri--methylellagic acid (), kaempferol (), 7,4'-dihydroxy-8-methoxyisoflavone (), and -caffeoyltyramine () were isolated from the aerial parts of . The structures of all isolated compounds were fully characterized using spectroscopic data, as well as comparison with the previous literature. Compound exhibited the strongest inhibitory activity toward glucosidase with IC value of 4.

A new 26-norlanostane from growing in Vietnam.

Chemical investigation on chloroform extract of led to the isolation of one new compound namely turgidol, together with five known triterpenoids, lupeol, lupenone, betulin, betulinic acid, and taraxerol. Their structures and stereochemistry have been determined by 1 D and 2 D NMR analysis, high resolution mass spectrometry, and compared with those in literatures. The relative configuration of turgidol was defined using DFT-NMR chemical shift calculations and subsequent DP4+ probability method.

Paresordin A, a new diphenyl cyclic peroxide from the lichen .

From the lichen Parmotrema praesorediosum, one new diphenyl peroxide, named praesordin A (1), together with four depsidones, including virensic acid (), protocetraric acid (), 8'--methylprotocetraric acid (), and furfuric acid () were purified. Their structures were chacracterized using extensive HR-ESI-MS and NMR spectroscopic methods. The isolated compounds () possessed stronger -glucosidase inhibitory activity (IC = 43.

Usneaceratins A and B, two new secondary metabolites from the lichen .

Two new compounds, comprising one dibenzofuran, named usneaceratin A (), and one phenolic acid, named usneaceratin B (), together with one known dibenzofuran, isousnic acid (), and two known phenolics, orsellinic acid () and methyl orsellinate () were clarified from the lichen using variously chromatographic methods. Their structures were testified by comprehensive HR-ESI-MS, and NMR spectroscopic analysis, and comparison with published data. Their -glucosidase inhibitory activity of all compounds was measured.

Two new phenolic compounds from the lichen growing in Vietnam.

Two new phenolic compounds, cristiferides A-B () together with six known compounds, 2,4-dihydroxyphthalide (), lecanoric acid (), orsellinic acid (), 5-chloroorsellinic acid (), methyl haematommate (), and methyl β-orsellinate () were isolated from the lichen (Taylor) Hale (Parmeliaceae). The structures of isolated compounds were identified from its spectroscopic data and by comparison with the literatures. Compounds - and were evaluated for alpha-glucosidase inhibition.

Reticulatin, a novel C-spiroterpenoid from the lichen growing in Vietnam.

A novel C-spiroterpenoid, reticulatin (), was isolated from the lichen (Taylor) M. Choisy (Parmeliaceae). Five previously-reported compounds were also isolated: zeorin (), leucotylin (), lupeol (), betulinic acid (), and dihydroreynosin ().

Three new diphenyl ethers from the lichen (Nyl.) Hale (Parmeliaceae).

Three new diphenyl ethers, named praesorethers E, F and G (, and ), were isolated from the lichen . Their chemical structures were elucidated on the basis of extensively spectroscopic analysis including HR-ESI-MS and NMR as well as comparison with previously published data. These compounds were evaluated for the cytotoxicity against three human cancer cell lines (HeLa, NCI-H460 and MCF-7) using SRB assay.