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A new isoflavone (Z)-5,7,4′-trihydroxy-3′-[3-hydroxy-3-methyl-1-butenyl] isoflavone (1) together with seven known isoflavones (2–8) were isolated from the fruits of the Ficus auriculata. Their structures were established on the basis of 1 D, 2 D-NMR spectroscopic data and HR-ESI-MS analysis. All compounds were evaluated for their antibacterial activities against five pathogenic bacteria in vitro. Compounds 3 and 4 exhibited significant antibacterial activities against five pathogenic bacteria with the MIC values ranging from 1.25 to 20 μg/mL. [ABSTRACT FROM AUTHOR]

A new lactone ficusine D (1), together with six known compounds (2-7) were isolated from the stems of the Ficus auriculata. The new compound 1 was a rare 12-membered lactone containing a quinone ring skeleton. The structure of the 1 was elucidated by comprehensive spectroscopic data. The relative and absolute configurations of 1 were elucidated by the ROESY analysis and biogenesis pathway. All compounds were evaluated for their antibacterial activities against six pathogenic bacteria in vitro. Compounds 6 and 7 exhibited potent antibacterial activities against Bacillus cereus with the MIC values of 2.5 and 5 μM, respectively. [ABSTRACT FROM AUTHOR]

One new lignan derivative 2,3-dimethyl-4-(4-methoxyphenyl)-6,7-dihydroxynaphthalene (1), together with five known compounds (2–6), were isolated from ethanol extract of the branches and leaves of Combretum alfredii Hance collected in Hainan Province, China. Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. Compounds 1, 2, 5 and 6 were isolated from the genus of Combretum for the first time. All compounds were evaluated for their antibacterial activities. Compounds 1 and 2 showed significant antibacterial activities against six pathogenic bacteria. [ABSTRACT FROM AUTHOR]

A new phenolic glycoside derivative, saproglucoside (1), along with five known phenolic glycoside derivatives (2–6) were isolated from the stems of Saprosma merrillii. The structure of the new compound 1 was determined by 1D and 2D NMR as well as by HRESIMS and hydrolysis. The inhibitory activities of all compounds against seven pathogenic bacteria and two cancer cell lines were evaluated. [ABSTRACT FROM AUTHOR]

Reinvestigating the chemical constituents of the roots of Xanthium sibiricum led to the isolation of a new naphthoquinone (1), together with 13 known compounds (2–14). Their structures were elucidated by using spectroscopic analyses, including HR-ESI-MS, 1D and 2D NMR, and by comparing their NMR data with those of related compounds. Compound 1 showed moderate antibacterial activity against Escherichia coli, Bacillus subtilis, Micrococcus tetragenus and Staphylococcus aureus, while 6 and 12 showed stronger antibacterial activity than the positive control ciprofloxacin against E. coli, with minimum inhibitory concentration values of 0.17 and 0.35 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

A novel lumazine peptide, aspergilumamide A ( 1), as well as a known analog penilumamide ( 2), were isolated from the mycelia of a marine-derived fungus Aspergillus sp. (33241), obtained from the mangrove Bruguiera sexangula var. rhynchopetala collected from the South China Sea. The structure of 1 was identified by comprehensive spectroscopic analysis, including 1D- and 2D-NMR, ESI-MS, and MS/MS experiments. The absolute configuration of 1 was determined by Marfey's method. [ABSTRACT FROM AUTHOR]

Three new methylated Δ 8-pregnene steroids, stemphylisteroids A–C (1 – 3) were isolated from the medicinal plant Polyalthia laui -derived fungus Stemphylium sp. AZGP4-2. Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. The absolute configuration of 1 was determined by X-ray crystallographic analysis. Compound 1 show antibacterial activity against Escherichia coli with the MIC value of 6.25 μg/mL, and 2 exhibited a broad spectrum of antibacterial activities against six pathogenic bacteria with the MIC values ranging from 12.5 to 50 μg/mL. The discovery of three methylated Δ 8-pregnene steroids 1 – 3 are a further addition to diverse and complex array of methylated steroids. [ABSTRACT FROM AUTHOR]