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Graphical abstract Highlights • The phytochemicals of a medicinal plant, Eriosema robustum, were re-investigated. • A new coumaronochromone (1) and a new furanoflavone (2) were isolated from the plant. • The structures of 1 and 2 were characterized by NMR and HR-ESIMS. • 1 and 2 exhibited weak activity with MICs > 150 μg/mL against bacteria and fungi. • 1 (IC 50 340.3 ± 0.1 μM) and 2 (IC 50 524.6 ± 0.1 μM) had weak antioxidant activity. Abstract A new coumaronochromone, eriocoumaronochromone (1), and a new alkanoyl-dihydrofuranoflavone glycoside, robusflavone C (2), as well as seven known compounds, 6-prenylpinocembrin (3), desmoxyphyllin A (4), prutin (5), genistein (6), vitexin (7), kaempferol (8), and p -hydroxy benzoic acid (9), were obtained after phytochemical re-investigation of the EtOAc-soluble portion from the EtOH extract of the twigs of Eriosema robustum. The structures of the new compounds were elucidated by analyses of their spectroscopic data (1D- and 2D- NMR, and HR-ESIMS) and chemical conversion. 1 and 2 exhibited weak antioxidant activity with IC 50 340.3 ± 0.1 and 524.6 ± 0.1 μM in 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical assay, and possessed weak antimicrobial activity with MICs > 150 μg/mL against Bacillus subtilis , Staphylococcus aureus , Klebsiella pneumoniae , Escherichia coli, Candida albicans , and Saccharomyces cerevisiae. [ABSTRACT FROM AUTHOR]

Abstract: In our search for lipid-droplets accumulation (LDA) inhibitors, some ceramicines, a series of limonoids isolated from the barks of Chisocheton ceramicus, were discovered to be active as anti-LDA. Preliminary structure–activity relationships (SAR) of ceramicines as LDA inhibitors based on ceramicines A–L (1–12) and ceramicine B derivatives were described. [Copyright &y& Elsevier]

Abstract Three new lignoids, premnan A (1), premnan B (2), and tauntangyiol C (3), were isolated from Premna serratifolia wood, a traditional cosmetic plant in Myanmar, together with a new lignoid, premnan C (4) assumed to be an artifact, one natural new lignoid (5), and three known lignoids (6 – 8). The structures of the new compounds 1 – 4 were elucidated based on 1D and 2D NMR, IR spectroscopy, and HRESIMS. The absolute configurations of 1 – 4 were also determined by optical rotation, circular dichroism (CD) data analyses, and comparisons with the reported literature. All isolated compounds were tested for their melanogenesis activities against the B16-F10 mouse melanoma cell line. Compounds 1 and 4 showed melanogenesis enhancing activities of 31% and 50%, respectively, at a 50 μM concentration. Compounds 2 , 3 , and 6 increased melanin production by 67%, 30%, and 45%, respectively, at a 100 μM concentration, without any cytotoxicity. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract: A novel C16N2-type Lycopodium alkaloid consisting of a quinolizidine with a 6-dimethylaminohexyl side chain, hupermine A (1), was isolated from the club moss of Huperzia phlegmaria, and the structure and relative stereochemistry were elucidated on the basis of spectroscopic data. [Copyright &y& Elsevier]

Abstract: A novel C16N-type Lycopodium alkaloid consisting of a decahydroquinoline and a cyclohexanone, huperminone A (1), was isolated from the club moss of Huperzia phlegmaria, and the structure and relative stereochemistry were elucidated on the basis of spectroscopic data. This unique C16N-type skeleton lacking in a nitrogen atom may be generated from C16N2-type phlegmarane skeleton. [Copyright &y& Elsevier]

Two new homodrimane sesquiterpenoids, globbatones A and B (1 and 2), and one 16-norlabdane diterpenoid, globbatone C (3), together with two new naturally occurring, (E)-labda-8(17),12-diene-15,16-olide (4) and γ-bicyclohomofarnesen-12-ol (5), and one known homodrimane sesquiterpenoid (6), nine known labdane diterpenoids (7 – 15), and one isospongian diterpenoid (16), were isolated from the chloroform extract of Globba sherwoodiana rhizomes. The structures of the new compounds 1 – 3 were elucidated based on 1D and 2D NMR and HRESIMS spectroscopic analyses. The chloroform extract of G. sherwoodiana rhizomes and 10 μM concentrations of some of its constituents 1 , 3 , 4 , 8 , 9 , 12 , and 14 showed the moderate anti-Vpr activities, without cytotoxic effects on the TREx-HeLa-Vpr cell line. Unlabelled Image [ABSTRACT FROM AUTHOR]

Two new tetrahydrofuran lignans, taungtangyiols A ( 1 ) and B ( 2 ), and eight known furofuran lignans ( 3 − 10 ), were isolated from the chloroform extract of Premna integrifolia wood collected in Myanmar. Their structures were elucidated by extensive spectroscopic techniques. The X-ray crystal structure of 1 clearly indicated its relative configuration. Taungtangyiols A ( 1 ) and B ( 2 ) inhibited the deposition of melanin in B16F10 mouse melanoma cells, with IC 50 values of 50.7 and 40.9 μM, respectively, without notable cytotoxicity. An SAR study demonstrated that the furofuran and dioxymethylene moieties of the lignans play a vital role in inhibiting melanogenesis. [ABSTRACT FROM AUTHOR]

Thirteen new triterpenoids, dysotriflorins A–M ( 1 – 13 ), were isolated from Dysoxylum densiflorum barks, and their structures were elucidated on the basis of NMR spectroscopic data and X-ray crystallography. Dysotriflorins A, B, and K–M ( 1 , 2 , and 11 – 13 ) were concluded to be unique 13,17-secodammarane triterpenoids, and dysotriflorins C–J ( 3 – 10 ) to be dammarane triterpenoids. Dysotriflorins showed in vitro cytotoxic activity against several cancer cell lines. [ABSTRACT FROM AUTHOR]

Abstract: Four new compounds, 2-hydroxy-6-(12′-hydroxyheptadec-13′(E)-en-1-yl)benzoic acid (1), 2-hydroxy-6-(13′-hydroxyheptadec-11′(E)-en-1-yl)benzoic acid (2), 2-hydroxy-6-(10′-hydroxypentadec-11′(E)-en-1-yl)benzoic acid (3), and 2-hydroxy-6-(11′-hydroxypentadec-9′(E)-en-1-yl)benzoic acid (4) were isolated from the leaves of Ginkgo biloba and the structures of new ginkgolic acids were deduced on the basis of spectroscopic methods and chemical means. Compounds 1 and 2, and 3 and 4 examined as an inseparable mixture of hydroxyl and double bond positional isomers, were ultimately defined by total synthesis. Compounds 1–4 showed moderate lipid droplets accumulation inhibitory activity on mouse pre-adipocyte cell line, MC3T3-G2/PA6. [Copyright &y& Elsevier]

Abstract: Six new limonoids, Walsogynes B (1)–G (6), were isolated from the barks of Walsura chrysogyne, and their structures were determined on the basis of NMR and MS spectroscopic analyses in combination with NMR chemical shifts calculations. Walsogynes (1)–E (4) were concluded to be 11,12-seco limonoids sharing a unique dodecahydronaphtho[1,8-bc:5,4-b′c′]difuran skeleton, and walsogynes F (5) and G (6) to be 11,12-seco limonoids with a dodecahydro-1H-naphtho[1,8-bc:3,4-c′]difuran skeleton. Their absolute configurations were assigned through comparison of the calculated and experimental CD spectra. Walsogynes showed a moderate in vitro cytotoxic activity against various cancer cell lines. [Copyright &y& Elsevier]

SmltD is an ATP-dependent ligase that catalyzes the condensation of UDP-MurNAc- l -Ala and l -Glu to form UDP-MurNAc- l -Ala- l -Glu, in the newly discovered peptidoglycan biosynthesis pathway of a Gram-negative multiple-drug-resistant pathogen, Stenotrophomonas maltophilia. Phytochemical investigation of the 70% ethanol extract from Woodfordia fruticosa flowers collected in Myanmar led to the identification of anti-SmltD active flavonoids, kaempferol 3- O -(6′′-galloyl)- β - d -glucopyranoside (1), astragalin (2), and juglalin (3). Among them, 1 showed the most potent SmltD inhibitory activity. An enzyme steady-state kinetic study revealed that 1 exerted competitive inhibition with respect to ATP. The results of this study provided an attractive foundation for the further development of novel inhibitors of SmltD. [ABSTRACT FROM AUTHOR]

Four new polyacetylene amides, siphonellamides A-D (1–4), and one new fatty amide, siphonellamide E (5), together with a known indole fatty amide (6) and callyspongamide A (7), were isolated from the Red Sea marine sponge Siphonochalina siphonella. The structures of 1–5 were elucidated by extensive analyses of their 1D- and 2D-NMR spectra and MS. The isolated compounds were assessed for their cytotoxicity against HeLa, MCF-7, and A549 cancer cell lines. Compounds 1 and 2 exhibited cytotoxic activities with IC 50 values ranging from 9.4 to 34.1 μM, while 5 was only cytotoxic to HeLa cells, with an IC 50 value of 78.4 μM. Compound 7 showed moderate cytotoxicity against all tested cell lines. Unlabelled Image [ABSTRACT FROM AUTHOR]