The methanol stem bark extract of and methanol seed extract of , were subjected to purification using chromatographic techniques. yielded loganic acid (), sweroside () and secoxyloganin (), while afforded , akuammidine (), akuammicine () and alstonine (). The structures of the compounds were elucidated based on their nuclear magnetic resonance (NMR), high-resolution mass spectrometry (HRMS) profiles and comparison with literature data.
View Article and Find Full Text PDFThe phytochemical investigation of the leaves of Inula confertiflora, a medicinal plant endemic to Ethiopia, led to the isolation of 15 terpenoids; 1β-hydroxy-α-costic acid (1), 3α-hydroxycostic acid (2), isotelekin (3), asperilin (4), carabrone (5), carpesioline (6), graveolide (7), inuviscolide (8), 8-epi-inuviscolide (9), 1β,4β-dihydroxy-5α(H)-guaia-10(14),11(13)-dien-8α,12-olide (10), isoinuviscolide (11), 4β,10β-dihydroxy-5α(H)-1,11(13)-guaidien-8α,12-olide (12), 4β,10β-dihydroxy-1β(H)-5α(H)-guai-11(13)-en-8α,12-olide (13), 4β,10α-dihydroxy-1β(H)-5α(H)-guai-11(13)-en-8α,12-olide (14), 4β,10α-dihydroxy-1α(H)-5α(H)-guai-11(13)-en-8α,12-olide (15). Herein, structural elucidation and full NMR data for compound 1 are presented for the first time. The structures were elucidated using NMR, HRESIMS, and by comparison with literature data.
View Article and Find Full Text PDFDiscopodium penninervium is a medicinal plant endemic to Ethiopia. Its twigs extract led to the isolation of three new withanolides, discopodinolides A - C, and four known analogues. The structures of the compounds were elucidated using NMR, HRMS data analyses, and literature data.
View Article and Find Full Text PDFis a medicinal plant widely used to treat oral pathogens, gonorrhea, fever, analgesics, asthma, joint pains, pneumonia, and intestinal worms in Ethiopia. Anticipated by these claims, column chromatographic separation of the roots extract of . led to the isolation of eight alkaloids (1-8).
View Article and Find Full Text PDFChemical investigation of the endophytic fungus, , isolated from healthy and asymptomatic common bean field crop, resulted in the isolation of a new alkene, ()-5-amino-5-(1,1,2-trihydroxybuta-1,3-dienyloxy)pentane-6,7,8,9-tetraol (), together with five known compounds (-). The structures of the compounds were elucidated by analysis of their spectroscopic data including 1 D, 2 D NMR, ESI-HRMS and literature data. The organic crude extract and the compound isolated from significantly (p ≤ 0.
View Article and Find Full Text PDFTetrapleura tetraptera is a medicinal plant used in East and West Africa to treat inflammation and related diseases. From the stem bark of the plant, three previously undescribed flavan-3-ol derivatives named (2R,3S)-3,3',5',7-tetrahydroxy-4'-methoxyflavane (1), (2R,3S)-3',5',7-trihydroxy-4'-methoxyflavane-3-O-β-D-glucopyranoside (2), and (2R,3S,4S)-3,3',4,5',7-pentahydroxy-4'-methoxyflavane (3) were isolated with three known analogues. The structural elucidation of the compounds was performed based on NMR spectroscopy and HRMS data analyses.
View Article and Find Full Text PDFFrom the leaves of Kenyan medicinal plant Bersama abyssinica Subspecies abyssinica, four previously undescribed compounds namely, three bufadienolides, 10β-formylpaulliniogenin B, 10β-formylpaulliniogenin A and 1β-acetoxy-3β,5β-dihydroxy-15-methoxy-16,19-dioxobufa-14(15),20,22-trienolide, and a phenolic compound 2,6,4'-trihydroxybenzophenone-4-O-(6‴-cinnamoyl)-β-D-glucoside were isolated together with four known compounds. The structural elucidation of the compounds was based on 1D and 2D NMR spectroscopy and HRMS data analyses. The relative configurations were defined by NOESY correlations.
View Article and Find Full Text PDFThree new bufadienolides, namely, paulliniogenin A (), paulliniogenin B (), and 16β-formyloxybersamagenin 1,3,5-orthoacetate (), together with two known bufadienolides and six known phenolic substances, were isolated from the stem bark of subsp. and subsp. .
View Article and Find Full Text PDFThe leaves of yielded 6 new flavonoids-3,5,7-trihydroxy-6-methyl-3',4'-methylenedioxyflavone (1: ), 5,7-dihydroxy-3-methoxy-6-methyl-3',4'-methylenedioxyflavone (2: ), 3,5,7-trihydroxy-6-methoxy-3',4'-methylenedioxyflavone (3: ), (2,3)-3,7-dihydroxy-6-methoxy-3',4'-methylenedioxyflavanone (4: ), 4',5,7-trihydroxy-3,3',8-trimethoxy-6-methylflavone (5: ), (2) 7-hydroxy-2',8-dimethoxyflavanone (6: )-together with 13 known congeners. Their structures were established using spectroscopic and spectrometric methods including NMR, CD, and HRMS measurements. The compounds were evaluated for their anti-inflammatory potential through measurement of the levels of cytokines IL-1, IL-2, GM-CSF, and TNF- in the supernatant of human peripheral blood mononuclear cells stimulated by lipopolysaccharide.
View Article and Find Full Text PDFFour new steroidal sapogenins, dracaenogenins CF (1-4), a new conjugated chalcone-stilbene, 3''-methoxycochinchinenene H (5) together with eight known compounds namely, (25S)-spirosta-1,4-dien-3-one (6), trans-resveratrol (7), 4,4'-dihydroxy-3'-methoxychalcone (8), N-trans-coumaroyltyramine (9), N-trans-p-coumaroyloctopamine (10), N-trans-feruloyloctopamine (11), 7-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-N,N-bis(4-hydroxyphenethyl)-6-methoxy-1,2-dihydronaphthalene-2,3-dicarboxamide (12) and grossamide (13) were isolated from the stems of Dracaena usambarensis Engl. from Kenya. It is important to note that compounds 12 and 13 are being reported from this genus for the first time.
View Article and Find Full Text PDFPhytochemical investigation of Tephrosia vogelii seedpods led to the isolation of twelve compounds: vogelisoflavone A (1), vogelisoflavone B (2), isopongaflavone (3), onogenin, luteolin, 4',7-dihydroxy-3'-methoxyflavanone, trans-p-hydroxycinnamic acid, tephrosin, 2-methoxygliricidol, dehydrorotenone, 6a,12a-dehydro-α-toxicarol and pinoresinol. Compounds 1 and 2 are reported as new natural products. Isopongaflavone (3) was structurally modified using hydrazine to pyrazoisopongaflavone (4).
View Article and Find Full Text PDFFrom the leaves of South African medicinal plant Melianthus comosus, four previously undescribed bufadienolides, 16β-formyloxymelianthugenin (1), 2β-acetoxymelianthusigenin (2), 2β-hydroxy-3β,5β-di-O-acetylhellebrigenin (3), and 2β-acetoxy-5β-O-acetylhellebrigenin (4) were isolated together with two known bufadienolides. The structural elucidation of the compounds was based on 1D and 2D NMR spectroscopy, high-resolution mass spectrometry, and other spectroscopic methods. The relative configurations were determined by single-crystal X-ray crystallography analysis and NOESY correlations.
View Article and Find Full Text PDFA new flavone, named hildeflavone () along with 7 other known flavonoids were isolated from the aerial parts of Vatke. Their characterisation was based on NMR and MS data analysis. The anti-inflammatory properties of the crude extract, isolated compounds and combination of the compounds were investigated in lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs).
View Article and Find Full Text PDFPhytochemical analysis of a methanol-dichloromethane (1:1) extract of the aerial parts of led to the isolation of 18 compounds. Seven of these, namely, lineaflavones A-D (-), 6-methoxygeraldone (), 8″-acetylobovatin (), and 5-hydroxy-7-methoxysaniculamin A () are new compounds. The compounds were characterized based on their NMR and HRMS data.
View Article and Find Full Text PDFPhytochemical studies of the seeds of the Cameroonian medicinal plant, Salacia staudtiana, resulted in the isolation and identification of five new cardenolides (1-5) as well as a new dihydro-β-agarofuran (9), along with eight known compounds. The structures of all compounds were elucidated by 1D/2D NMR, ESI-HRMS data and comparison with literature data. The relative configurations of the new compounds were defined by X-ray crystallography analysis, NOESY correlations and coupling constants.
View Article and Find Full Text PDFSeven new cardenolides, staudtianoside A-F (1-6) and staudtianogenin A (8), were isolated along with six known compounds from the stem bark of the Cameroonian medicinal plant Salacia staudtiana Loes. ex Fritsch. The structures were elucidated by means of ESI-HRMS and NMR spectroscopic methods and by comparison with literature data.
View Article and Find Full Text PDFSix new flavanones (1-6), together with six known compounds were isolated from Erythrina livingstoniana. Their structures were elucidated on the basis of NMR data and HRMS(n) fragmentation pathway and by comparison with literature data. Compounds 5, 7 and 8 showed remarkable DPPH free radical scavenging efficacies.
View Article and Find Full Text PDFThe chemical study of Erythrina livingstoniana has led to the isolation of three new flavanones namely 5,7,3'-trihydroxy-4'-methoxy-5'-formylflavanone (erylivingstone A) (1), 5,7,3'-trihydroxy-5'-(2-hydroxy-3-methylbut-3-enyl)-4'-methoxyflavanone (erylivingstone B) (2) and 5,7,3'-trihydroxy-5'-(3-hydroxy-3-methyl-trans-but-1-enyl)-4'-methoxyflavanone (erylivingstone C) (3) together with three known compounds (4-6). Their structures were elucidated on the basis of NMR data, HRMS(n) fragmentation pathway and by comparison with literature data. We evaluated the antibacterial efficacies and free-radical scavenging potential of the isolated compounds (1-6).
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