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A new bakuchiol compound Δ 11 -12-hydroxy-12-dimethyl bakuchiol ( 1 ), a new flavanone compound 2( S )-6-methoxy-7- hydroxymethylene-4′-hydroxyl-flavanone ( 8 ), and two new isoflavanone compounds 4′,7-dihydroxy-3′-(6”β-hydroxy-3″,7″-dimethyl-,2″,7″-dibutenyl)-geranylisoflavone ( 9 ) and 4′,7-dihydroxy-3′-(7″-hydroxy-7″-methyl-2″,5″-dibutenyl)-geranylisoflavone ( 10 ) together with eight known compounds ( 2–7 , 11 , 12 ) were isolated from the P. corylifolia . Their structures were elucidated on the basis of spectroscopic and physico-chemical analyses. All the isolates were evaluated for in vitro inhibitory activity against DGAT1/2. Among them, compounds 3 , 9 and 10 were found to exhibit selective inhibitory activity on DGAT1 with IC 50 values ranging from 93.7 ± 1.3 to 96.2 ± 1.1 μM. Compound 1 showed inhibition activity on DGAT1 with IC 50 values 73.4 ± 1.3 μM and inhibition of DGAT2 with IC 50 value 121.1 ± 1.3 μM. [ABSTRACT FROM AUTHOR]

Phytochemical examination of the leaves and stems of Viscum articulatum resulted in the isolation of three pairs of new flavanone glycosides, 2 R /2 S -viscarticulide A–C ( 1a/1b – 3a/3b ), together with eight known compounds ( 7 – 14 ). Their structures were established by extensive spectroscopic data analyses. The diastereoisomers were separated by HPLC on a chiral phase and the absolute configuration at C-2 was determined by circular dichroism (CD) spectra. The protective effects of compounds 1 – 3 against H 2 O 2 -induced cytotoxicity with EA.hy926 cells were tested. The results showed that compounds 1 – 3 improved the survival of EA.hy926 cells after H 2 O 2 exposure at the tested concentrations. [ABSTRACT FROM AUTHOR]

Abstract: Propolis of Australian stingless bees (Tetragonula carbonaria, Meliponini) originating from Corymbia torelliana (Myrtaceae) fruit resins was tested for its antimicrobial activities as well as its flavonoid contents. This study aimed at the isolation, structural elucidation and antibacterial testing of flavanones of C. torelliana fruit resins that are incorporated into stingless bee propolis. Flavanones of this study were elucidated by spectroscopic and spectrometric methods including UV, 1D and 2D NMR, EI-MS, ESI-MS and HR-MS. The results indicated known C-methylated flavanones namely, 1 (2S)-cryptostrobin, its regioisomer 2 (2S)- stroboponin, 3 (2S)- cryptostrobin 7-methyl ether, and 6 (2S)- desmethoxymatteucinol, and known flavanones 4 (2S)- pinostrobin and 5 (2S)- pinocembrin as markers for C. torelliana fruit resins and one propolis type. Ethanolic preparations of propolis were shown to be active against Staphylococcus aureus (ATCC 25923) and to a lesser extent against Pseudomonas aeruginosa (ATCC 27853). C. torelliana flavanones inhibited the growth of S. aureus therefore contributing to the antibacterial effects observed for Australian stingless bee propolis extracts. [Copyright &y& Elsevier]

Abstract: In an effort to identify natural compounds with immunosuppressive activity, nine new flavonoids, including one isoflav-3-ene derivative (1), one coumaronochromone (2), two isoflavanones (3, 4), one isoflavone derivative (6), one isoflavone (7), three flavonols (8, 9, 10), as well as one known compound, hydroisoflavone C (5), were isolated from the roots of Campylotropis hirtella. The structures of these compounds were elucidated by extensive spectroscopic measurements. All of the compounds were assessed for immunosuppressive activity. Among the isolates, compound 2 showed good inhibitory activity against mitogen-induced splenocyte proliferation with an IC50 of 0.28μM and relatively low cytotoxicity. [Copyright &y& Elsevier]

Abstract: One (formosumone A, 1) new and fifteen (2–16) known phenolic compounds were isolated from the leaves of Cratoxylum formosum ssp. pruniflorumm, a substitute for the popular bitter nail tea (“Kuding Tea”) generally used in Southeast Asia. Their structures were determined by extensive spectroscopic analysis and by comparison with literature data. Compound 1 possesses a rare scaffold of a flavanone coupled with a phloroglucinol moiety, representing the first example of such a scaffold from the Clusiaceae family. Among the isolates, toxyloxanthone B (11) and vismione D (12) were found to show remarkable anti-neuroinflammatory effects by inhibiting nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated murine BV-2 microglial cells. Additionally, toxyloxanthone B (11) exhibited significant neuroprotective effect against β-amyloid25–35 (Aβ 25–35)-induced cell viability decrease in SH-SY5Y neuroblastoma cells. [Copyright &y& Elsevier]

Abstract: Two new flavanones with a C15 isoprenoid group, japonicasins A and B (1 and 2), were isolated from the leaves of Sophora japonica. This is the first report on the presence of the (2E,7E)-6-isopropyl-3,9-dimethyldeca-2,7,9-trien-1-yl group (C15 isoprenoid group) in isoprenylated flavonoids. Their structures were determined by spectroscopic methods, including UV, IR, 1D and 2D NMR, HRESIMS, and CD experiments. In addition, the antioxidant activities of compounds 1 and 2 were determined through DPPH radical scavenging assays. They exhibited potential antioxidant activities, with IC50 values of 35.1±0.8 μM and 88.7±1.1 μM for compounds 1 and 2, respectively. [Copyright &y& Elsevier]