Antimicrobial Dihydroflavonols and Isoflavans Isolated from the Root Bark of .

Three new dihydroflavonols, gloverinols A-C (-), a new flavon-3-ol, gloverinol D (), two new isoflavans, gloveriflavan A () and B (), and seven known compounds were isolated from the root bark of . The structures of the isolates were elucidated by using NMR, ECD, and HRESIMS data analyses. Among the isolated compounds, gloverinol B (), gloveriflavan B (), and 1-(2,4-dihydroxyphenyl)-3-hydroxy-3-(4-hydroxyphenyl)-1-propanone () were the most active against , with MIC values of 9.

Antiviral Rotenoids and Isoflavones Isolated from ssp. .

Three new (-) and six known rotenoids (-), along with three known isoflavones (-), were isolated from the leaves of ssp. . A new glycosylated isoflavone (), four known isoflavones (-), and one known chalcone () were isolated from the root wood extract of the same plant.

Benzo[]naphtho[2,1-]furans and 2-Phenylnaphthalenes from .

Three new benzo[]naphtho[2,1-]furans, usambarins A-C (-), five new 2-phenylnaphthalenes, usambarins D-H (-), a new flavan (), and a new phenyl-1-benzoxepin () as well as two known compounds ( and ) were isolated from the extract of the stem and roots of (Moraceae). The structures were deduced using NMR spectroscopic and mass spectrometric analyses, and those of compounds and were confirmed by X-ray crystallography. Usambarin D () demonstrated moderate antibacterial activity (MIC 9.

Cytotoxicity of isoflavones from .

The first phytochemical investigation of the flowers of resulted in the isolation of seven isoflavones, a flavonol and a chalcone. Eleven isoflavones and a flavonol isolated from various plant parts from this plant were tested for cytotoxicity against a panel of cell lines, and six of these showed good activity with IC values of 6-14 μM. Durmillone was the most active with IC values of 6.

Methods for Identifying Microbial Natural Product Compounds that Target Kinetoplastid RNA Structural Motifs by Homology and De Novo Modeled 18S rRNA.

The development of novel anti-infectives against Kinetoplastids pathogens targeting proteins is a big problem occasioned by the antigenic variation in these parasites. This is also a global concern due to the zoonosis of these parasites, as they infect both humans and animals. Therefore, we need not only to create novel antibiotics, but also to speed up the development pipeline for these antibiotics.

Antileishmanial and cytotoxic activity of secondary metabolites from and two species.

In this study, the antileishmanial and cytotoxic activities of secondary metabolites isolated from Hochst. ex A. DC.

Antiplasmodial and antileishmanial flavonoids from Mundulea sericea.

Five known compounds (1-5) were isolated from the extract of Mundulea sericea leaves. Similar investigation of the roots of this plant afforded an additional three known compounds (6-8). The structures were elucidated using NMR spectroscopic and mass spectrometric analyses.

Synthesis of a pyrrolidine derivative of a carvotacetone and monoterpenes for anti-methicillin-resistant and anti-cryptococcal properties.

Monoterpene derivatives are of great biological relevance in the pharmaceutical industry. In the present study, pyrrolidine derivative of a carvotacetone, 3-benzylcarvotacetone (), and selected monoterpenes (3-hydroxy-2-isopropyl-5-methyl--benzoquinone () and piperitol ()) were prepared to provide ()-1-(4-(benzyloxy)-5-isopropyl-2-methylcyclohexa-1,3-dien-1-yl)-pyrrolidine (), 2-isopropyl-5-methyl-3,6-dioxocyclohexa-1,4-dien-1-yl acetate (), 3-hydroxypiperitone () and carvacrol (). Structure of was determined based on NMR and HRMS spectral data.

Isoflavones from the seedpods of Tephrosia vogelii and pyrazoisopongaflavone with anti-inflammatory effects.

Phytochemical 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).

Synergistic anti-inflammatory activities of a new flavone and other flavonoids from vatke.

A 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).

Anti-inflammatory Flavanones and Flavones from .

Phytochemical 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.

Synthesis, structural assignments and antiinfective activities of 3--benzyl-carvotacetone and 3-hydroxy-2-isopropyl-5-methyl--benzoquinone.

In an attempt to synthesize carvotacetone analogues, new 3--benzyl-carvotacetone ( and previously reported 3-hydroxy-2-isopropyl-5-methyl--benzoquinone () were synthesized from piperitone (). In this work, we describe the synthesis of and other analogues from . Luche reduction of to -piperitol (, followed by benzylation yielded 3--benzyl-piperitol ().

Cytotoxicity of isoflavones and biflavonoids from Ormocarpum kirkii towards multi-factorial drug resistant cancer.

Background: While incidences of cancer are continuously increasing, drug resistance of malignant cells is observed towards almost all pharmaceuticals. Several isoflavonoids and flavonoids are known for their cytotoxicity towards various cancer cells.

Purpose: The aim of this study was to determine the cytotoxicity of isoflavones: osajin (1), 5,7-dihydroxy-4'-methoxy-6,8-diprenylisoflavone (2) and biflavonoids: chamaejasmin (3), 7,7″-di-O-methylchamaejasmin (4) and campylospermone A (5), a dimeric chromene [diphysin(6)] and an ester of ferullic acid with long alkyl chain [erythrinasinate (7)] isolated from the stem bark and roots of the Kenyan medicinal plant, Ormocarpum kirkii.

Evaluation of β-Sitosterol Loaded PLGA and PEG-PLA Nanoparticles for Effective Treatment of Breast Cancer: Preparation, Physicochemical Characterization, and Antitumor Activity.

β-Sitosterol (β-Sit) is a dietary phytosterol with demonstrated anticancer activity against a panel of cancers, but its poor solubility in water limits its bioavailability and therapeutic efficacy. In this study, poly(lactide-co-glycolic acid) (PLGA) and block copolymers of poly(ethylene glycol)-block-poly(lactic acid) (PEG-PLA) were used to encapsulate β-Sit into nanoparticles with the aim of enhancing its in vitro anticancer activity. β-Sitosterol-loaded PLGA and PEG-PLA nanoparticles (β-Sit-PLGA and β-Sit-PEG-PLA) were prepared by using a simple emulsion-solvent evaporation technique.

Cytotoxic benzylbenzofuran derivatives from Dorstenia kameruniana.

Chromatographic separation of the extract of the roots of Dorstenia kameruniana (family Moraceae) led to the isolation of three new benzylbenzofuran derivatives, 2-(p-hydroxybenzyl)benzofuran-6-ol (1), 2-(p-hydroxybenzyl)-7-methoxybenzofuran-6-ol (2) and 2-(p-hydroxy)-3-(3-methylbut-2-en-1-yl)benzyl)benzofuran-6-ol(3) (named dorsmerunin A, B and C, respectively), along with the known furanocoumarin, bergapten (4). The twigs of Dorstenia kameruniana also produced compounds 1-4 as well as the known chalcone licoagrochalcone A (5). The structures were elucidated by NMR spectroscopy and mass spectrometry.

Cytotoxic flavonoids from two species.

A new isoflavone, 4'-prenyloxyvigvexin A () and a new pterocarpan, (6a,11a)-3,8-dimethoxybitucarpin B () were isolated from the leaves of and the stem bark of , respectively. The extract of also gave four known isoflavones, maximaisoflavone H, 7,2'-dimethoxy-3',4'-methylenedioxyisoflavone, 6,7,3'-trimethoxy-4',5'-methylenedioxyisoflavone, durmillone; a chalcone, 4-hydroxylonchocarpin; a geranylated phenylpropanol, colenemol; and two known pterocarpans, (6a,11a)-maackiain and (6a,11a)-edunol. (6a,11a)-Edunol was also isolated from the stem bark of .

Four Prenylflavone Derivatives with Antiplasmodial Activities from the Stem of Tephrosia purpurea subsp. leptostachya.

Four new flavones with modified prenyl groups, namely ()-5-hydroxytephrostachin (), purleptone (), ()-5-hydroxyanhydrotephrostachin (), and terpurlepflavone (), along with seven known compounds (-), were isolated from the CH₂Cl₂/MeOH (1:1) extract of the stem of subsp. , a widely used medicinal plant. Their structures were elucidated on the basis of NMR spectroscopic and mass spectrometric evidence.

Anthraquinones of the roots of Pentas micrantha.

Pentas micrantha is used in the East African indigenous medicine to treat malaria. In the first investigation of this plant, the crude methanol root extract showed moderate antiplasmodial activity against the W2- (3.37 μg/mL) and D6-strains (4.

Antiplasmodial quinones from Pentas longiflora and Pentas lanceolata.

The dichloromethane/methanol (1:1) extracts of the roots of Pentas longiflora and Pentas lanceolata showed low micromolar (IC(50) = 0.9-3 µg/mL) IN VITRO antiplasmodial activity against chloroquine-resistant (W2) and chloroquine-sensitive (D6) strains of PLASMODIUM FALCIPARUM. Chromatographic separation of the extract of PENTAS LONGIFLORA led to the isolation of the pyranonaphthoquinones pentalongin (1) and psychorubrin (2) with IC(50) values below 1 µg/mL and the naphthalene derivative mollugin (3), which showed marginal activity.

Antimalarial pyrido[1,2-a]benzimidazoles.

A novel class of antimalarial pyrido[1,2-a]benzimidazoles were synthesized and evaluated for antiplasmodial activity and cytotoxicity following hits identified from screening commercially available compound collections. The most active of these, TDR86919 (4c), showed improved in vitro activity vs the drug-resistant K1 strain of Plasmodium falciparum relative to chloroquine (IC(50) = 0.047 μM v 0.

Directed ring-opening of 1,5-dioxaspiro[3.2]hexanes: selective formation of 2,2-disubstituted oxetanes.

1,5-Dioxaspiro[3.2]hexanes undergo ring-opening reactions with many heteroatom nucleophiles to provide alpha-substituted-beta'-hydroxy ketones. However, certain Lewis acidic nucleophiles provide 2,2-disubstituted oxetanes.

Unusual, strained heterocycles: 3-alkylidene-2-methyleneoxetanes from Morita-Baylis-Hillman-type adducts.

[reaction: see text] 3-Alkylidene-2-methyleneoxetanes have been prepared by treating alpha-alkylidene-beta-lactones, derived from Morita-Baylis-Hillman-type adducts, with dimethyltitanocene. Preliminary studies of the reactivity of these little known, strained heterocycles are also described.

Synthesis of D-erythro-dihydrosphingosine and D-xylo-phytosphingosine from a serine-derived 1,5-dioxaspiro[3.2]hexane template.

[reaction: see text] A serine-derived 1,5-dioxaspiro[3.2]hexane template is shown to be a useful precursor for both aminodiol and aminotriol sphingoid bases by its conversion to D-erythro-dihydrosphingosine and D-xylo-phytoshingosine.