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Two new isoflavanones, erybrucein A and B ( 1 , 2 ), together with nineteen known compounds are reported herein from the stem and root bark of the Ethiopian medicinal plant, Erythrina brucei . All known compounds, except erythraline ( 19 ), have been isolated for the first time from E. brucei . Their structures were established on the basis of extensive spectroscopic and spectrometric analyses (1D and 2D NMR, CD, IR and ESI-HRMS n ) and confirmed by comparison with reported- and DFT-calculated data. The absolute configuration of kenusanone F ( 3 ) and the 7-methyl ether ( 4 ) were determined in the same way. Antibacterial properties as well as DPPH radical scavenging activities of the new isoflavanones and selected known compounds were evaluated. Although most tested compounds showed weak activity against the tested organisms, erybrucein B ( 2 ) showed moderate activity (MIC = 0.062 mg/mL) against Bacillus cereus . In the DPPH radical scavenging assays, compounds 1 , 2 , and 3 showed moderate activity whereas two other compounds showed high activity. [ABSTRACT FROM AUTHOR]

Two new phenanthrene alkaloids, beilschglabrines A ( 1 ) and B ( 2 ) were isolated from the stem bark of Beilschmiedia glabra , together with lupeol, taraxerol, and 24-methylenelanosta-7,9-diene-3β-15α-diol. The structures of the isolated compounds were elucidated by extensive spectroscopic data analysis and comparison with respective literature data. The compounds were tested for DPPH radical scavenging, acetylcholinesterase and lipoxygenase inhibitory activities. Compound 1 displayed considerable activity in the acetylcholinesterase (IC 50 50.4 μM), the DPPH radical scavenging (IC 50 115.9 μM) and the lipoxygenase (IC 50 32.8 μM) assays. [ABSTRACT FROM AUTHOR]

Two new highly-oxygenated flavonoid glycosides, gossypetin-5- O -(6″-( E )-caffeoyl)- β -d-glucoside ( 1 ) and herbacetin-5- O -(6″-( E )-caffeoyl)- β - d -glucoside ( 2 ) were isolated from the leaves of Eupatorium adenophorum Spreng. Their structures were determined by spectroscopic methods including one- and two-dimensional NMR, and HR-ESI–MS. Compounds have potent DPPH radical scavenging activity with IC 50 12.0 μM ( 1 ) and 22.9 μM ( 2 ) (Vc as positive control, IC 50 59.0 μM) and inhibitory activity onproliferation of preadipocyte 3T3-L1 cells. [ABSTRACT FROM AUTHOR]

Seven new triterpenoids ( 1 – 7 ), together with two known ones ( 8 – 9 ), were isolated from the aerial parts of Ilex cornuta . The leaves of I. cornuta are the major source of “Kudingcha”, a popular herbal tea consumed in China and other countries. The structures of compounds 1 – 7 were determined as 20 -epi- urs-12,18-dien-28-oic acid 3β- O -α- l -arabinopyranoside ( 1 ), 20 -epi- urs-12,18-dien-28-oic acid 2′- O -acetyl-3β- O -α- l -arabinopyranoside ( 2 ), 20- epi -urs-12,18-dien-28-oic acid 3β- O -β- d -glucuronopyranoside-6- O -methyl ester ( 3 ), 3β,23-dihydroxy-20 -epi- urs-12,18-dien-28-oic acid ( 4 ), 23-hydroxy-20 -epi- urs-12,18-dien-28-oic acid 3β- O -α- l -arabinopyranoside ( 5 ), 23-hydroxy-20 -epi- urs-12,18-dien-28-oic acid 3β- O -β- d -glucuronic acid ( 6 ), 23-hydroxy-20- epi -urs-12,18-dien-28-oic acid 3β- O -β- d -glucuronopyranoside-6- O -methyl ester ( 7 ), on the basis of spectroscopic analyses (IR, ESI–MS, HR-ESI–MS, 1D and 2D NMR) and chemical reactions. Protective effects against H 2 O 2 -induced H9c2 cardiomyocyte injury were tested in vitro for compounds 1 – 9 , and the data showed that compound 4 had significant cell-protective effect. Compounds 1 - 9 did not show significant DPPH radical scavenging activity. [ABSTRACT FROM AUTHOR]

Bioassay-guided fractionation of the marine-derived endophytic fungus Paecilomyces variotii resulted in the isolation of two new butenolides, namely, butyrolactone IX ( 1 ) and aspulvinone O ( 7 ), together with eight known related congeners, butyrolactones I, IV, V, and VI ( 2 – 5 ), aspernolide A ( 6 ), and aspulvinones H, C, and D ( 8 – 10 ). Their structures were elucidated on the basis of detailed spectroscopic analysis and by comparison with literature data. All of the isolated butenolides were tested for their activity against DPPH radicals and the results showed that butyrolactones ( 1 – 6 ) possessed potent activity with IC 50 values ranging from 38.0 to 186.3 μM, while aspulvinones ( 7 – 10 ) exhibited significant activities with IC 50 values ranging from 11.6 to 29.4 μM, which are stronger than that of the positive control BHT (with IC 50 117.7 μM). The preliminary structure–activity relationship was discussed. [ABSTRACT FROM AUTHOR]

Abstract: Three new phenolic compounds, sorlanin (4-(3-(hydroxymethyl)-5-methoxy-7-phenyl-2,3-dihydrobenzo[b][1,4]dioxin-2-yl)-2-methoxyphenol, 1), sorbanin (2-((3,5-dimethoxy-[1,1′-biphenyl]-4-yl)oxy)-1-(4-hydroxy-3-methoxyphenyl)propane-1,3-diol, 2) and sorbalanin (4-(3-(hydroxymethyl)-5,6-dimethoxy-2,3-dihydrobenzo[b][1,4]dioxino[2,3-g]benzofuran-2-yl)-2-methoxyphenol, 3), together with eight known compounds, polystachyol (4), isolariciresinol (5), dihydrodehydrodiconiferyl alcohol (6), tuberculatin (7), ovafolinin E (8), aucuparin (9), 2′-methoxyaucuparin (10), and tetracosyl-3-(3,4-dihydroxyphenyl)acrylate (11), were isolated from Sorbus lanata. The structures of these phytoconstituents were elucidated through extensive spectroscopic techniques, including UV, IR, 1D and 2D NMR, ESI-MS and HRESI-MS experiments. All the compounds except 9 and 10 were isolated for the first time from the genus Sorbus. The isolated compounds were also tested in DPPH radical scavenging reaction where compounds 6, 7, 10 and 11 showed significant activities with IC50 values of 9.2, 11.7, 23.0 and 33.7μM, respectively. [Copyright &y& Elsevier]

Abstract: Three new flavonoids, lawsochrysin (1), lawsochrysinin (2), and lawsonaringenin (3) were isolated from the leaves of Lawsonia alba Lam. along with four flavonoids 3′,4′-dimethoxy flavone (4), 7-hydroxy flavone (5), 3,3′,4′,7-tetrahydroxy flavanone (6) and rhoifolin (7) hitherto unreported from this genus. Their structures were elucidated on the basis of spectroscopic evidences. Compounds (3) and (6) showed a good urease inhibition activity IC50 =139.1±0.77 and 184.53±0.61μM respectively, (6) also showed a DPPH radical scavenging activity with IC50 =33.83μM. [Copyright &y& Elsevier]

Abstract: Extracts from aerial parts and roots of Tanacetum L. (emend. Briq.) chiliophyllum (Fisch. & Mey.) var. monocephalum Grierson from Turkey were investigated for their DPPH scavenging activity and contact toxicity against Sitophilus granarius. The ethyl acetate extract of aerial parts yielded a new sesquiterpene lactone 1-epi-chiliophyllin (1) which is a derivative of the compound chiliophyllin previously isolated from T. chiliophyllum var. heimerlei. Also known compounds; neolupenyl acetate (lup-12-ene-3β-acetate) (2), 4′,5,7-trihydroxy-3′,8-dimethoxyflavone (3), 4′,5,7-trihydroxy-8-methoxyflavone (4) were isolated together with (1). Structures of the compounds were determined by spectral methods including UV, IR, MS and 1D, 2D NMR. Highest contact toxicity against the stored granary products pest S. granarius was observed after 48h (68.49±0.67%). Highest DPPH scavenging activity observed for ethyl acetate extract of the roots at 10mg/mL concentration (87.8±0.84%). The DPPH scavenging activities of the pure flavonoids (3,4) at 1mg/mL concentration were unsignificant (3, 16.4±0.16%; 4, 17.6±0.82%) when compared with the positive controls α-tocopherol (91.7±1.07%) and BHT (91.7±0.37%) at the same concentration. [Copyright &y& Elsevier]