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Background: Discovering new lead compounds against malaria parasites is a crucial step to ensuring a sustainable global pipeline for effective anti-malarial drugs. As far as we know, no previous phytochemical or pharmacological investigations have been car

A study of diterpenoids as active ingredients against cancer from the active roots extract of Casearia barteri Mast. (IC 50 = 1.57 μg mL -1 ) led to the isolation of six new clerodane diterpenoids, named as barterins A-F (1-6) alongside seven known compounds, caseamembrin A, caseamembrin E, casearlucin A, graveospene G, N-trans -feruloyltyramine, N-cis -feruloytyramine and sitosterol-3- O -β- D -(6- O -palmitoyl)-glucopyranoside. Their structures were elucidated based on NMR spectroscopic data and mass spectrometry. The absolute configurations of 1-6 were established by the time-dependent density functional theory (TDDFT), electronic circular dichroism (ECD) calculations and experimental data analysis. The cytotoxic effects of compounds 1-6 were evaluated against a human cervix carcinoma cell line KB -3-1. Barterins A-D (1-4) showed cytotoxic effects against the KB -3-1 cell line with IC 50 values ranging from 1.34-4.73 μM., Competing Interests: The authors declare no conflict of interest that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)

Alzheimer's disease (AD) and diabetes are non-communicable diseases with global impacts. Inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are suitable therapies for AD, while α-amylase and α-glucosidase inhibitors are employed as antidiabetic agents. Compounds were isolated from the medicinal plant Terminalia macroptera and evaluated for their AChE, BChE, α-amylase, and α-glucosidase inhibitions. From 1 H and 13 C NMR data, the compounds were identified as 3,3'-di-O-methyl ellagic acid ( 1 ), 3,3',4'-tri-O-methyl ellagic acid-4-O-β-D-xylopyranoside ( 2 ), 3,3',4'-tri-O-methyl ellagic acid-4-O-β-D-glucopyranoside ( 3 ), 3,3'-di-O-methyl ellagic acid-4-O-β-D-glucopyranoside ( 4 ), myricetin-3-O-rhamnoside ( 5 ), shikimic acid ( 6 ), arjungenin ( 7 ), terminolic acid ( 8 ), 24-deoxysericoside ( 9 ), arjunglucoside I ( 10 ), and chebuloside II ( 11 ). The derivatives of ellagic acid ( 1 - 4 ) showed moderate to good inhibition of cholinesterases, with the most potent being 3,3'-di-O-methyl ellagic acid, with IC 50 values of 46.77 ± 0.90 µg/mL and 50.48 ± 1.10 µg/mL against AChE and BChE, respectively. The compounds exhibited potential inhibition of α-amylase and α-glucosidase, especially the phenolic compounds ( 1 - 5 ). Myricetin-3-O-rhamnoside had the highest α-amylase inhibition with an IC 50 value of 65.17 ± 0.43 µg/mL compared to acarbose with an IC 50 value of 32.25 ± 0.36 µg/mL. Two compounds, 3,3'-di-O-methyl ellagic acid (IC 50 = 74.18 ± 0.29 µg/mL) and myricetin-3-O-rhamnoside (IC 50 = 69.02 ± 0.65 µg/mL), were more active than the standard acarbose (IC 50 = 87.70 ± 0.68 µg/mL) in the α-glucosidase assay. For α-glucosidase and α-amylase, the molecular docking results for 1-11 reveal that these compounds may fit well into the binding sites of the target enzymes, establishing stable complexes with negative binding energies in the range of -4.03 to -10.20 kcalmol -1 . Though not all the compounds showed binding affinities with cholinesterases, some had negative binding energies, indicating that the inhibition was thermodynamically favorable.

Two new glycosylflavones, 6''- O -acetyl-8- C - β - D -galactopyranosylchrysoeriol ( 1 ) and 8- C - β - D -galactopyranosylchrysoeriol ( 2 ) were isolated from the methanol extract of the leaves of Ochna afzelii Oliv., along with four known compounds namely 8- C - β - D -galactopyranosylapigenin ( 3 ), ochnaflavone ( 4 ), sitosterol-3- O - β-D- glucopyranoside ( 5 ) and D -mannitol ( 6 ). Isolation was performed chromatographically and the structures of the purified compounds were elucidated by analyzing their spectroscopic and mass spectrometric data. The antibacterial activity of extract, fractions, and compounds 1 - 4 was evaluated using broth microdilution method against Gram-positive and Gram-negative bacteria while the antioxidant capacity was performed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and the ferric reducing antioxidant power (FRAP) methods. The new flavones ( 1 and 2 ) displayed moderate antibacterial activities (MIC = 32 - 64 µg/mL) and weak antioxidant properties.

The CH 2 Cl 2 -MeOH (1:1) extract of roots of Rumex nepalensis (Polygonaceae) displayed significant antibacterial activity against five bacterial strains with MICs (62.5-31.2 μg.mL -1 ). The EtOAc soluble fraction displayed a significant activity against the same strains with MICs (31.2-3.9 μg.mL -1 ). The purification of the EtOAc fraction yielded one new phenylisobenzofuranone derivative, berquaertiide ( 1 ), along with 19 known compounds ( 2 - 20 ). Their structures were elucidated based on the analysis of their NMR and MS data. All the isolated compounds were assessed for their antibacterial activity. Compound 2 was the most active against all the tested strains (15.7 to 1.9 μg.mL -1 ), while compounds 3 - 7 displayed good activities on at least one of the tested strains. In addition, seven analogues ( 21 - 27 ) of compound 2 were prepared and further assessed for their antibacterial activity. Compounds 26 and 27 were most active than 2 against Salmonella enterica and Klebsiella pneumoniae with MIC (125 and 15.6 μg.mL -1 , respectively).

Background: Microbial infections cause serious health problems especially with the rising antibiotic resistance which accounts for about 700,000 human deaths annually. Antibiotics which target bacterial death encounter microbial resistance with time, hence, there is an urgent need for the search of antimicrobial substances which target disruption of virulence factors such as biofilm and quorum sensing (QS) with selective pressure on the pathogens so as to avoid resistance., Methods: Natural products are suitable leads for antimicrobial drugs that can inhibit bacterial biofilms and QS. Twenty compounds isolated from the medicinal plant Gambeya lacourtiana were evaluated for their antibiofilm and anti-quorum sensing effects against selected pathogenic bacteria., Results: Most of the compounds inhibited violacein production in Chromobacterium violaceum CV12472 and the most active compound, Epicatechin had 100% inhibition at MIC (Minimal Inhibitory Concentration) and was the only compound to inhibit violacein production at MIC/8 with percentage inhibition of 17.2 ± 0.9%. Since the bacteria C. violaceum produces violacein while growing, the inhibition of the production of this pigment reflects the inhibition of signal production. Equally, some compounds inhibited violacein production by C. violaceum CV026 in the midst of an externally supplied acylhomoserine lactone, indicating that they disrupted signal molecule reception. Most of the compounds exhibited biofilm inhibition on Staphyloccocus aureus, Escherichia coli and Candida albicans and it was observed that the Gram-positive bacteria biofilm was most susceptible. The triterpenoids bearing carboxylic acid group, the ceramide and epicatechin were the most active compounds compared to others., Conclusion: Since some of the compounds disrupted QS mediated processes in bacteria, it indicates that this plant is a source of antibiotics drugs that can reduce microbial resistance., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Four polyoxygenated stigmastanes ( 1 - 4 ) alongside known analogues ( 7 - 8 ) and flavonoids ( 5 - 6 ) were isolated from a dichloromethane/methanol (1:1, v / v ) extract of the whole plant of Vernonia kotschyana Sch. Bip. ex Walp. (Asteraceae). Their structures were determined by means of spectroscopic and spectrometric analysis. The relative stereochemistry of the new compounds was established and confirmed via biosynthesis evidence and cyclization of 1 under acidic conditions. A plausible biosynthetic pathway to the new compounds and the chemophenetic significance of the isolated constituents were also discussed. The crude extract, fractions, and compounds ( 1 - 3 ) were assessed for their antibacterial activity against five highly prevalent bacterial strains. The fractions and compounds showed low to moderate activity with minimal inhibitory concentrations (MICs) > 125 µg/mL.

Background: Dacryodes edulis is a plant that belongs to the Burseraceae family. It is widely used traditionally alone or in association with other plants in Cameroonian folk medicine to cure wounds, fever, headaches, and malaria. The aim of this work was to investigate the leaves and stem bark of D. edulis with an emphasis on the antiplasmodial and cytotoxic effects of extracts, fractions, and isolated compounds., Methods: Extracts, fractions, and some isolated compounds were subjected to antiplasmodial activity screening in vitro against chloroquine-sensitive 3D7 and multidrug resistant Dd2 strains of Plasmodium falciparum using a SyBr Green fluorescence-based assay. The cytotoxicity of active extracts, fractions, and compounds was tested against mammalian Raw cell lines using an in vitro resazurin-based viability assay. The structures of the compounds were determined based on their NMR and MS data. The in vivo toxicity using female BALB/c mice was performed on the most active extract according to the protocol of OECD (2002), guideline 423., Results: The hydroethanolic extract from the leaves of D. edulis displayed good antiplasmodial activity with IC 50 values of 3.10 and 3.56 μg/mL respectively on sensitive (3D7) and multiresistant (Dd2) strains of P. falciparum. Of the sixteen compounds isolated, 3,3',4-tri-O-methylellagic acid (4) exhibited the highest antiplasmodial activity against PfDd2 strains with an IC 50 value of 0.63 μg/mL. All extracts, fractions, and isolated compounds demonstrated no cytotoxicity against Raw cell lines with CC 50  > 250 μg/mL. In addition, the most active extract on both strains of P. falciparum was nontoxic in vivo, with a LD 50 greater than 2000 and 5000 mg/kg. A phytochemical investigation of the stem bark and leaves of D. edulis afforded sixteen compounds, including two xanthones (1-2), three ellagic acid derivatives (3-5), one phenolic compound (6), one depside (7), one triglyceride (8), one auranthiamide acetate (9), one gallic acid derivative (10), four triterpenoids (11-14), and two steroids (15-16). Compounds 1, 2, 5, 7, 8, and 9 were herein reported for the first time from the Burseraceae family., Conclusion: This work highlights the good in vitro antiplasmodial potency of the hydroethanolic extract of the leaves of this plant and that of two isolated constituents (3,3',4-tri-O-methylellagic acid and ethylgallate) from the plant. These biological results support the use of D. edulis in traditional medicine against malaria., (© 2023. The Author(s).)

The bio guided fractionation of the dichloromethane/methanol (1:1) crude extract of the air-dried whole plant of C. aegyptiaca led to the isolation of one new flavone derivative designated conyflavone ( 1 ) and one new clerodane diterpene type designated conyclerodane ( 2 ) along with five known compounds including two flavonoids Gardenin C ( 3 ), chrysosplenetin ( 4 ) and two steroids glucoside of β -sitosterol ( 5 ), the mixture of stigmasterol ( 6 ) and β -sitosterol ( 6' ) and ent-2b,18,19trihydroxycleroda-3,13-dien-16,15-olide ( 7 ). The structures were established by spectroscopic methods including IR, 1D and 2D NMR in conjunction with mass spectroscopy and by comparison to data of related compounds described in literature. The stereocentres in compound 2 were determined by SC-XRD analysis. Crude extract as well as fractions and pure compounds were evaluated in vitro for their antibacterial activities against four pathogenic and two clinical isolate strains using microdilution methods. Extracts and compounds displayed a moderate antibacterial activity with MIC values ranging from 125 to 500 µg/mL.

Medicinal plants attract the attention of many researchers to find natural and safe remedies for various resistant diseases. Leaves of Mitragyna inermis are widely used in traditional veterinary medicine for the treatment of gastrointestinal strongyles of small ruminants. The aim of the current study is to estimate the antioxidant, anthelmintic and the larval toxicity of the aqueous and hydroethanolic extracts of this plant in addition to the hexane, dichloromethane and ethanol fractions of the hydroethanolic extract. Investigation of the most active extract using Ultra Performance Liquid Chromatography coupled with Quadrupole Time-of-Flight Electrospray Ionization Mass Spectrometry (UPLC-QToF-ESI-MS). Both plant extracts showed good antioxidant activity by scavenging the 2,2'-diphényl-1-picrylhydrazyl (DPPH) radical and reducing the ferric ion. Similarly, they were no-toxic to Artemia salina larvae (CL 50  > 0.1 μg/mL). Also, they significantly reduced larval migration and motility of Haemonchus contortus adult worms (p < 0.001). The hexane, dichloromethane and ethanolic fractions of the hydroethanolic extract showed low activity compared to crude extracts except for the hexane fraction on H. contortus adult worms (p < 0.001) while it showed a poor result on larvae. It thus appears that the anthelmintic activity of the extract may be linked to the synergistic action of these compounds. The UPLC-QToF-ESI-MS analysis revealed the tentative identification of 15 compounds including 7 alkaloids. The results of the present study confirm the anthelmintic activity of M. inermis in traditional veterinary medicine., Competing Interests: The authors have no interests to declare., (© 2023 The Authors.)

The phytochemical investigation of the methanol extract of the stem bark of Chrysophyllum lacourtianum led to the isolation and characterization of one new secondary metabolite, lacourtianal ( 1 ), together with eight known compounds. Compounds 2 ; 3 ; 5 ; 6 ; 7 and 9 were reported for the first time from Chrysophyllum genus. The structures of compounds 1 - 9 were elucidated on the basis of 1 D and 2 D NMR spectroscopic and mass spectrometric data as well as comparison with the literature. The antibacterial activity of the methanol extract, fractions and compounds 1 - 9 were evaluated against bacterial strains. The methanol extract exhibited moderate activity against Staphylococcus aureus NR4674 with MIC values of 500 µg/mL. The n -hexane fraction showed moderate activity against Staphylococcus aureus (ATCC 43300 and ATCC 25923) with MIC values of 125 µg/mL and ursolic acid ( 5 ) exhibited strong activity against Enterobacter aerogenes CPC and Escherichia coli ATCC 25322 with MIC values of 7.8 and 3.9 µg/mL respectively.

The chemical investigation of the n -hexane fraction from the methanol extract of the stem bark of Symphonia globulifera Linn f., which displayed good in vitro activity against Leishmania donovani NR-48822 promastigotes (IC 50 43.11 µg/mL), led to the isolation of three previously unreported polyprenylated benzophenones, guttiferone U ( 1 ), V ( 2 )/W ( 3 ), and a new tocotrienol derivative named globuliferanol ( 4 ), along with 11 known compounds ( 5 - 15 ). Their structures were elucidated based on their NMR and MS data. Some isolated compounds were assessed for both their antileishmanial and cytotoxic activities against L. donovani and Vero cells, respectively. Guttiferone K ( 5 ) exhibited the best potency (IC 50 3.30 μg/mL), but with low selectivity to Vero cells. The n -hexane fraction and some compounds were also assessed in vitro for their antibacterial activity against seven bacterial strains. All the samples exhibited moderate to potent antibacterial activity (MICs ≤ 15.6 µg/mL) against at least one of the tested strains.

Crotofoligandrin ( 1 ), a new endoperoxide crotofolane-type diterpenoid was isolated from the dichloromethane/methanol (1:1) extract of the twigs of Croton oligandrus Pierre Ex Hutch along with thirteen known secondary metabolites including 1-nonacosanol ( 2 ), lupenone ( 3 ), friedelin ( 4 ), β -sitosterol ( 5 ), taraxerol ( 6 ), (-)-hardwickiic acid ( 7 ), apigenin ( 8 ), acetyl aleuritolic acid ( 9 ), betulinic acid ( 10 ), fokihodgin C 3-acetate ( 11 ), D-mannitol ( 12 ), scopoletin ( 13 ) and quercetin ( 14 ). The structures of the isolated compounds were determined based on their spectroscopic data. The crude extract and the isolated compounds were assessed in vitro for their antioxidant, lipoxygenase, butyrylcholinesterase (BChE), urease and glucosidase inhibitory potentials. Compounds 1 - 3, and 10 displayed activities on all the performed bioassays. All the tested samples showed strong to significant antioxidant activity with compound 1 being the most potent (IC 50 39.4 μM)., (© 2023 Walter de Gruyter GmbH, Berlin/Boston.)

The chemical investigation of the EtOH extract from the stem bark of Trichilia monadelpha (Thonn.) J. J. De Wilde afforded two new limonoids ( 1 and 2 ): 24-acetoxy-21,25-dihydroxy-21,23-epoxytirucall-7-en-3-one ( 1 ) and (6 R )-1- O -deacetylkhayanolide E ( 2 ), together with eleven known compounds ( 3 - 13 ), including additional limonoids, flavonoids, triterpenoids, steroids, and fatty acid. Their structures were determined using 1D- and 2D-NMR experiments, ESI mass spectrometry, and single crystal X-ray diffraction analysis. The antibacterial and antiplasmodial activities of the extracts, sub-extracts, fractions, and some of the isolated compounds were evaluated in known pathogenic strains, including Staphylococcus aureus and Plasmodium falciparum . Fraction E ( n -Hex/EtOAc 30:70, v / v ) showed significant activity against S . aureus ATCC 25923 with a MIC value of 3.90 µg/mL, while one of its constituents (epicatechin ( 9 )) exhibited significant activity with MIC values of 7.80 µg/mL. Interestingly, grandifotane A ( 6 ) (IC 50 = 1.37 µM) and khayanolide D ( 5 ) (IC 50 = 1.68 µM) were highly active against the chloroquine-sensitive/sulfadoxine-resistant plasmodium falciparum 3D7 strain, unlike their corresponding plant extract and fractions.

A phytochemical investigation of the roots of Citrus × paradisi Macfad. (Rutaceae) led to the isolation of two new compounds, namely 1-formyl-5-hydroxy- N -methylindolin-1-ium ( 1 ) and decyloxycleomiscosin D ( 2 ), along with ten known compounds: 1,1-dimethylpyrrolidin-1-ium-2-carboxylate ( 3 ), furan-2,3-diol ( 4 ), 5-methoxyseselin ( 5 ), umbelliferone ( 6 ), scopoletin ( 7 ), citracridone I ( 8 ), citracridone II ( 9 ), citracridone III ( 10 ), limonin ( 11 ) and lupeol ( 12 ). The structures were determined through the comprehensive spectroscopic analysis of 1D and 2D NMR and EI- and ESI-MS, as well as a comparison with the published data. Notably, compounds 3 and 4 from the genus Citrus are reported here for the first time. In addition, the MeOH extract of the roots and compounds 1 - 7 were screened against the human adenocarcinoma alveolar basal epithelial cell line A549 and the Caucasian prostate adenocarcinoma cell line PC3 using the MTT assay. While the extract showed significant activity, with IC 50 values of 35.2 and 38.1 µg/mL, respectively, compounds 1 - 7 showed weak activity, with IC 50 values of 99.2 to 250.2 µM and 99.5 to 192.7 µM, respectively., Competing Interests: The authors declare no conflict of interest.

Eleven previously undescribed arylnaphthalide lignans ( 1 - 11 ) together with seven known compounds were isolated from the whole plant of Justicia depauperata . The structures of 1 - 11 were elucidated by spectroscopic analysis and mass spectrometry. Compounds 6 (IC 50 = 4.1 μM) and 9 (IC 50 = 9.5 μM) displayed cytotoxic activity against the KB-3-1 cervical carcinoma cell line. This report provides an insight into the conformational equilibria occurring in the arylnaphthalide lignan constituents of this plant.

As part of our search for new secondary metabolites from Macaranga hurifolia Beille, a phytochemical investigation was carried out on the fruits that led to the isolation and characterization of two new prenylated flavonol derivatives named macafolias A ( 1 ) and B (2 ), along with five known compounds. Their chemical structures were established on the basis of extensive analysis of their 1-D and 2-D NMR ( 1 H, 13 C, APT, COSY, HSQC and HMBC) in conjunction with mass spectroscopy and by comparison with data from the literature. The in vitro assay of the antibacterial potency of the crude extract, fractions and some pure compounds were evaluated against a wide range of bacteria strains.

This paper describes eight new triterpenoid saponins, including afzeliioside A ( 1 ), four acetylated afzeliiosides as pairs of inseparable regioisomers, called afzeliiosides B/C ( 2/3 ) and D/E ( 4/5 ), afzeliiosides F-H ( 6-8 ), and a known impatiprin C ( 9 ), which were isolated from the n -BuOH fraction of the liana of Microglossa afzelii . Their structures were established mainly by extensive spectroscopic analysis, including 1D and 2D NMR, HRFAB-MS, tandem ESI-MS/MS, and chemical methods, as well as a comparison of their spectral data with those of related compounds. All the isolates were screened for their cytotoxic activity against the CAL-27 oral squamous carcinoma cell line. Only compounds 4/5 (EC 50 = 36.0 μg/mL (32.7 μM)) exhibited moderate cytotoxic activity. This work presents the first chemical and biological investigation of Microglossa afzelii and reports, for the first time, on the isolation of saponins in the genus Microglossa .

An extensive phytochemical investigation of the EtOH/H 2 O (7:3) extracts of Sida rhombifolia L. and Sida acuta Burm. f., yielded a previously undescribed ceramide named rhombifoliamide ( 1 ) and a xylitol dimer ( 2 ), naturally isolated here for the first time, as well as the thirteen known compounds viz , oleanolic acid ( 3 ), β -amyrin glucoside ( 4 ), ursolic acid ( 5 ), β -sitosterol glucoside ( 6 ), tiliroside ( 7 ), 1,6-dihydroxyxanthone ( 8 ), a mixture of stigmasterol ( 9 ) and β -sitosterol ( 10 ), cryptolepine ( 11 ), 20-Hydroxyecdysone ( 12 ), ( E )-suberenol ( 13 ), thamnosmonin (1 4 ) and xanthyletin (1 5 ). Their structures were elucidated by the analyses of their spectroscopic and spectrometric data (1 D and 2 D NMR, and HRESI-MS) and by comparison with the previously reported data. The crude extracts, fractions, and some isolated compounds were tested against chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) Plasmodium falciparum strains. All the tested samples demonstrated moderate and/or significant activities against 3D7 (IC 50 values: 0.18-20.11 µg/mL) and Dd2 (IC 50 values: 0.74-63.09 µg/mL).[Formula: see text].

Chemical investigation of Allophylus africanus P. Beauv fruits led to the isolation of a new δ -tocotrienol, 3 α -hydroxy-δ-tocotrienol ( 1 ) together with eight known compounds ( 2 - 9 ). Compound ( 1) was allylated ( 1a ) and prenylated ( 1 b and 1c ) to give three new semi-synthesized derivatives which were fully characterized as: 6- O -allyl-3 α -hydroxy-δ-tocotrienol ( 1a ), 6- O -prenyl-3 α -hydroxy-δ-tocotrienol ( 1 b ) and 6- O ,5-C-diprenyl-3 α -hydroxy-δ-tocotrienol ( 1c ). The structures of compounds were established using comprehensive spectroscopic analysis including UV, MS, 1 D NMR, 2 D NMR and by comparison with the corresponding literature data. Compound ( 1 ) and its semi-synthetic derivatives ( 1a-c ) were tested for their antioxydant activity using DPPH radical scavenging assay and also for their cytotoxicity using human cervix carcinoma KB-3-1 cell lines. The results showed that compound ( 1) exhibited antioxidant activity with an IC 50 value of 0.25  μ M compared to the reference control trolox (26  µ M); and good cytotoxic activity with IC 50 values of 97  μ M compared to the reference (+)-griseofulvin (IC 50 between17-21  μ M).

A phytochemical study of the methanol extract of the fruit of Maesa lanceolata resulted in the isolation of a new alkenylbenzoquinone ( 1 ), alongside the known compounds ( Z )-2,5-dihydroxy-6-methyl-3-(pentadec-10'-enyl)-1,4-benzoquinone ( 2 ), 2,5-dihydroxy-6-methyl-3-(nonadec-14'-enyl)-1,4-benzoquinone ( 3 ), 2,5-dihydroxy-6-methyl-3-(tridecyl)-1,4-benzoquinone ( 4 ), (2 S ,3 S ,4 R ,2' R ,9E)-[2'-hydroxytetraeicosanoyl]-2-aminooctadec-9-ene-1,3,4-triol ( 5 ), monopalmitin (glyceryl palmitate) ( 6 ), lupeol ( 7 ), and 3- O -( β -D-glucopyranoside)- β -sitosterol ( 8 ). The structures of the compounds were established by the means of spectroscopic (1 D- and 2 D-NMR) and spectrometric techniques (MS). The isolated compounds were assessed for their antibacterial, cytotoxic, and antiradical activities. Compound 2 showed moderate activity against Staphylococcus warneri (DSMZ 20036), while the other compounds were inactive. The two quinones 1 and 2 were significantly cytotoxic, with IC 50 values of 0.005  µ M and 12.5  µ M respectively, and were weakly active towards DPPH radical (IC 50 >250  µ g/mL).

Ripe figs, barks, and wood of Ficus vallis-choudae are used in traditional medicine against several conditions including nausea and malaria. However, its use is still to be scientifically documented and validated. Hence, the aim of the present work was to evaluate the antiplasmodial activity of the dichloromethane-methanol (DCM-MeOH (1:1)) crude extract, their hexane, dichloromethane, ethyl acetate, and methanoli fractions, as well as the isolated chemical constituents. The chemical study of the DCM-MeOH (1:1) crude extract of F. vallis-choudae figs led to the isolation of fifteen (15) known compounds identified based on their spectroscopic data [one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR), mass spectrometry] and by comparison of these data with those reported in the literature. Some of the isolated compounds were assessed in vitro for their antiplasmodial activity against Plasmodium falciparum chloroquine-sensitive 3D7 (Pf3D7) and multidrug-resistant Dd2 strains. The dichloromethane fraction exhibited very good antiplasmodial activity against both strains with IC 50 values of 13.86 μg/mL and 8.18 μg/mL, respectively. Among the tested compounds, wighteone (2) was the most active against P. falciparum 3D7 (IC 50  = 24.6 ± 1.5 μM) and Dd2 (IC 50  = 11.9 ± 2.4 μM) strains. The obtained results could justify the traditional uses of F. vallis-choudae against malaria. Wighteone appears to be the most active ingredient. However, further consideration of this compound as starting point for antimalarial drug discovery will depend upon its selectivity of action towards Plasmodium parasites. HIGHLIGHTS: • 15 (fifteen) compounds were isolated from the dichloromethane-methanol extract of Ficus vallis-choudae. • Their structures were determined on the basis of their spectroscopic data. • The dichloromethane fraction showed promising activities on the Pf3D7 and PfDd2 strains with IC 50 values of 13.86 and 8.18 µg/mL, respectively. • Wighteone was the most active compound against PfDd2 (IC 50  = 11.9 ± 2.4 μM)., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Two new fatty acid esters of triterpenoids ( 1 - 2 ) together with eleven known compounds ( 3 - 13 ) were obtained after investigation of the CH 2 Cl 2 -MeOH (1:1) crude extract from the leaves of Schefflera barteri Harms. All these compounds ( 1 - 13 ) were isolated for the first time from this plant among which compounds 3 , 4 , 6 and 9 - 13 were also isolated from the genus Schefflera for the first time. The structures of the isolated compounds were elucidated by analyses of their spectroscopic data (1D and 2D NMR, and MS). The antibacterial and cytotoxic activities of crude extracts, fractions and compounds ( 1 , 2 , 5 , 6 , 8 and 9 ) were investigated against both Gram-negative and Gram-positive bacteria strains as well as on human cervix carcinoma and colon adenocarcinoma cancer cell lines, respectively. They showed weak to significant activity towards the strains and malignant cells used.

The chemical investigation of the total alkaloid extract (TAE) of the stem bark of Araliopsis soyauxii (Rutaceae) afforded an unreported indolopyridoquinazoline (compound 1 ) along with nine previously known alkaloids 2 - 10 . In addition, six semi-synthetic derivatives 3a - c , 4b , 5a and 6a were prepared by allylation and acetonidation of soyauxinium nitrate ( 5 ), edulinine ( 3 ), ribalinine ( 4 ) and arborinine ( 6 ). The structures and spectroscopic data of five of them are reported herein for the first time. The suggested mechanism for the formation of the new N -allylindolopyridoquinazoline 5a is presented. The structures of natural and derived compounds were determined employing extensive NMR and MS techniques. The absolute configuration of stereogenic centers in compounds 2 - 4 were determined using NOESY technique and confirmed by the single-crystal X-ray diffraction (SC-XRD) technique. The use of SC-XRD further enabled us to carry out a structural revision of soyauxinium chloride recently isolated from the same plant to soyauxinium nitrate ( 5 ). The TAE, fractions, compounds 1 - 7 and 9 , and semi-synthetic derivatives 3a - c , 4b , 5a and 6a were evaluated for their cytotoxic activity towards the cervix carcinoma cell line KB-3-1. No significant activity was recorded for most of the compounds except for 9 , which showed moderate activity against the tested cancer cell lines.

The phytochemical investigation of the methanol extract of the stem bark of Gilbertiodendron dewevrei led to the isolation of two new secondary metabolites, 5,7-dihydroxy-4'-methoxyisoflavan-2,4-dione ( 1 ) and 23-hydroxy-2-tricosanone ( 2 ) along with 19 known compounds ( 3-21 ). The structure of these compounds were established by interpretation of their spectral data, mainly HR-TOFESIMS, 1 D NMR ( 1 H, 13 C and DEPT) and 2 D NMR ( 1 H- 1 H COSY, HSQC, HMBC, and NOESY), and by comparison with those reported in the literature. The methanol extract and some isolates were screened for their antiradical, antibacterial, and inhibitory properties against acetylcholinesterase.

Stem barks of Boswellia dalzielii are used traditionally for the treatment of various bacterial infections. A bioassay guided fractionation of the MeOH-CH 2 Cl 2 (1/1, v/v) stem barks extract led to the isolation of fourteen compounds 1-14 , identified based on spectroscopic data. Dalzienoside ( 1) is reported here for the first time. The broth microdilution method was used to evaluate the antibacterial activity of the crude extract, fractions and compounds against six bacterial strains. The crude extract exhibited moderate antibacterial activity with MIC of 250 μL/ml; two fractions showed significant activities with MICs ranging from 7.8 to 125 μg/ml, while α -boswellic acid ( 2 ), β -boswellic acid ( 3 ), acetyl-11-keto- β -boswellic acid ( 4 ) from these fractions exhibited strong activities with MIC value of 3.125 µg/mL against Staphylococcus aureus, Salmonella typhi, Enterobacter cloacae, Streptococcus pneumonia and Pseudomonia aeruginosa . This study gives insight into the antibacterial constituents of the stem bark of B. dalzielii and justifies its use in ethnomedicine.

Methanolic extracts of liana of Caesalpinia welwitschiana and leaves of C. bonduc were found to possess moderate antifeedant and ovicidal activities against Tuta absoluta . Bioassay-guided isolation of constituents from the most active fraction of C. welwitschiana led to the identification of four known compounds [isobonducellin 1a and bonducellin 1 b , intricatinol 2 , (-)-epigallocatechin-3- O -gallate 4 ] and one new constituent [welwitschianic acid 3 ]. The most active fraction of C. bonduc afforded two known constituents neocaesalpin L 5 and neocaesalpin A 6 . The isolated structures were elucidated on the basis of their MS, UV, IR and 1 & 2 D NMR spectra and by comparison with literature data. Compounds 2 , 4 - 6 were showed antifeedant and ovicidal properties against T. absoluta, some comparable to that of azadirachtin at 50, 100 and 200 ng/µl. Overall, the present study, conclude that the two species of the plant could be a promising source of eco-friendly botanical constituents.

The antiplasmodium assay-guided investigation of the roots, stem bark, and leaves of Persea americana Mill. led to the isolation of a new fatty alcohol, perseatriol ( 1 ), along with six known compounds ( 2-7 ). Their structures were elucidated based on the analysis of their NMR and MS data. All crude extracts and fractions exhibited good antiplasmodial activity on Plasmoduim falciparum 3D7 with IC 50 values ranging from 0.76 to 10.5 μg/mL; they also displayed cytotoxicity against HeLa cells with low selectivity indexes (SIs). A preliminary Plasmodium lactate dehydrogenase (pLDH) assay was also performed on the isolated compounds. 9,9'-Di- O -feruloyl-5,5'-dimethoxysecoisolariciresinol ( 4 ) turned out to be non-toxic and displayed the best activities on P. falciparum with an IC 50 value of 0.05 μM, comparable to the reference drug chloroquine with an IC 50 value of 0.03 μM. Furthermore, besides compound 4 , this work reports the first isolation of lutein ( 2 ) and scopoletin ( 3 ) from P. americana . The crude extracts of roots, stem bark, and leaves of P. americana , their fractions and compounds completely suppressed the growth of P. falciparum . The observed activity supports the use of P. americana in folk medicine for the treatment of malaria., (© 2021 Walter de Gruyter GmbH, Berlin/Boston.)

A total of nine sesquiterpenoid lactones together with phenolic compounds and other terpenes were identified from the crude methanol extract of Elephantopus mollis Kunth. Compounds were isolated using different chromatographic techniques and their structures were determined by NMR and IR spectroscopy as well as mass spectrometry. The structures of some detected compounds were assigned based on LC-ToF-ESI-MS screening of main fractions/subfractions from flash chromatography and comparison with isolated analogues as standards. The findings revealed not only the in-source loss of water as the base peak in hirsutinolides but also the in-source loss of corresponding alcohol when the oxygen at position 1 is alkylated. The present study also draws up a complement of data with respect to hirsutinolide-like sesquiterpene lactones whose LC-MS characteristics are not available in the literature. The chemophenetic significance is also discussed. Some of the isolated compounds were reported for the first time to be found in the species, the genus as well as the plant family. The medium-polar fractions of the crude extract, also containing the larger amount of sesquiterpenoid lactones, exhibited activity both against a cancer cell line and bacterial strains. Isolated lactones were also active against the cancer cell line, while the chlorogenic derivatives also valuable in Elephantopus genus showed potent radical scavenging activity. This is the first report of cytotoxic and antibacterial activities of our samples against the tested strains and cell line. The present study follows the ongoing research project dealing with the characterization of taxa with antibacterial and antiparasitic activities from Cameroonian pharmacopeia.

The local botanical Imperata cylindrica in Cameroon was investigated for its antibacterial potency. The methanol extract afforded a total of seven compounds, including five hitherto unreported compounds comprising three flavonoids ( 1 - 3 ) and two C-15 isoprenoid analogues ( 4 and 5 ) together with known derivatives ( 6 and 7 ). The novelty of the flavonoids was related to the presence of both methyl and prenyl groups. The potential origin of the methyl in the flavonoids is discussed, as well as the chemophenetic significance of our findings. Isolation was performed over repeated silica gel and Sephadex LH-20 column chromatography and the structures were elucidated by (NMR and MS). The crude methanol extract and isolated compounds showed considerable antibacterial potency against a panel of multi-drug resistant (MDR) bacterial strains. The best MIC values were obtained with compound ( 2 ) against S. aureus ATCC 25923 (32 µg/mL) and MRSA1 (16 µg/mL).

Emerging drug-resistant bacteria creates an urgent need to search for antibiotics drugs with novel mechanisms of action. Endophytes have established a reputation as a source of structurally novel secondary metabolites with a wide range of biological activities. In the present study, we explore the antibacterial potential of endophytic fungi isolated from different tissues of Terminalia mantaly , Terminalia catappa , and Cananga odorata . The crude ethyl acetate extracts of 56 different endophytic fungi were screened against seven bacterial strains using the broth microdilution method. The antibacterial modes of action of the most active extracts (04) were evaluated using E. coli ATCC 25922 and H. influenzae ATCC 49247 strains. Both the DPPH and FRAP assays were used to investigate their antioxidant activity, and their cytotoxicity against the Vero cell line was evaluated using the MTT assay. Out of the 56 crude extracts tested, about 13% were considered very active, 66% partially active, and 21% nonactive against all tested bacterial strains with MIC values ranging from 0.32  μ g/mL to 25  μ g/mL. The four more potent extracts (MIC <5  μ g/mL) (from Aspergillus sp. N454, Aspergillus sp. N13, Curvularia sp. N101, and Aspergillus sp. N18) significantly lysed the bacteria cells, increased outer membrane permeability, reduced salt tolerance, and inhibited bacterial catalase activity. They exhibited a DPPH free radical scavenging activity with IC 50 ranging from 150.71 to 936.08  μ g/mL. Three of the four potent extracts were noncytotoxic against the Vero cells line (CC 50 > 100  μ g/mL). Results from this investigation demonstrated that endophytes from Cameroonian medicinal plants might content potent antibacterial metabolites. The bioguided fractionation of these potent extracts is ongoing to isolate and characterise potential active ingredients., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 Michele Ines Kanko Mbekou et al.)

Ethnopharmacological Relevance: Malaria is a life-threatening health problem worldwide and treatment remains a major challenge. Natural products from medicinal plants are credible sources for better anti-malarial drugs., Aim of the Study: This study aimed at assessing the in vitro and in vivo antiplasmodial activities of the hydroethanolic extract of Bridelia atroviridis bark., Materials and Methods: The phytochemical characterization of Bridelia atroviridis extract was carried out by High-Performance Liquid Chromatography-Mass spectrometry (HPLC-MS). The cytotoxicity test on Vero cells was carried out using the resazurin-based assay while the in vitro antiplasmodial activity was determined on Plasmodium falciparum (Dd2 strain, chloroquine resistant) using the SYBR green I-based fluorescence assay. The in vivo assay was performed on Plasmodium berghei-infected rats daily treated for 5 days with distilled water (10 mL/kg) for malaria control, 25 mg/kg of chloroquine sulfate for positive control and 50, 100 and 200 mg/kg of B. atroviridis extract for the three test groups. Parasitaemia was daily monitored using 10% giemsa-staining thin blood smears. At the end of the treatment, animals were sacrificed, blood was collected for hematological and biochemical analysis while organs were removed for biochemical and histopathological analyses., Results: The HPLC-MS analysis data of B. atroviridis revealed the presence of bridelionoside D, isomyricitrin, corilagin, myricetin and 5 others compounds not yet identified. Bridelia atroviridis exhibited good in vitro antiplasmodial activity with the IC 50 evaluated at 8.08 μg/mL and low cytotoxicity with the median cytotoxic concentration (CC 50 ) higher than 100 μg/mL. B. atroviridis extract significantly reduced the parasitemia (p < 0.05) with an effective dose-50 (ED-50) of 89 mg/kg. B. atroviridis also prevented anemia, leukocytosis and liver and kidneys impairment by decrease of transaminases, ALP, creatinine, uric acid, and triglycerides concentrations. As well, B. atroviridis extract decreased some pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) levels and significantly improved the anti-inflammatory status (P < 0.01) of infected animals marked by a decrease of IL-10 concentration. These results were further confirmed by the improved of antioxidant status and the quasi-normal microarchitecture of the liver, kidneys and spleen in test groups. Overall, the hydroethanolic bark extract of Bridelia atroviridis demonstrated antimalarial property and justified its use in traditional medicine to manage malaria disease., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The phytochemical exploration of the Entandrophragma candollei stem bark extract led to the isolation and identification of twenty compounds including three undescribed phragmalin-class limonoids named encandollens C-E (1-3), the undescribed protolimonoid 5 together with sixteen known compounds. The structures of all the isolated compounds were determined by interpretation of their spectroscopic and spectrometric data including HRMS, 1D and 2D NMR analyses. The assignment of the absolute and relative stereochemistry of the undescribed compounds was achieved using SC-XRD analyses as well as NOESY experiments. The previously reported structure of odoratone (5a) was corrected as 23 R,24 S-dihydroxy-22 S,25-epoxytirucall-7-en-3-one (5) based on its NMR and SC-XRD data. Prieurianin (4) exhibited high cytotoxic activity on KB3-1 cell lines with an IC 50 of 1.47 μM compared to the reference griseofulvin (IC 50  = 17-21 μM). The results of the in silico docking of compound 4 supported and delivered further insights on its cytotoxicity., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The phytochemical investigation of Tarenna grandiflora led to the isolation of 18 known compounds of which were four flavones, three anthraquinones, one phenyl propanoic derivative, five triterpenoids, four steroids and a mixture of glucose. Luteolin ( 1 ) and soranjidiol ( 6 ) were allylated and/or prenylated to give four new semisynthesized derivatives which were fully characterized as 7,3',4'- O -triallylluteolin ( 1a ), luteolin-7,3',4'- O -triprenyls ( 1b ), luteolin-5,7,3',4'- O -tetraprenyls ( 1c ) and 6- O -allylsoranjidiol ( 6a ). Their structures were established using spectroscopic analysis including 1D, 2D NMR and MS data. The cytotoxic, antioxidant and antimicrobial activities of extracts, fractions, isolated compounds and semi-synthesized derivatives were evaluated. The petroleum ether and EtOAc extracts exhibited good cytotoxic potency on KB-3-1 cell line with IC 50 of >0.1 and 0.025 mg/mL respectively, while compounds 1b and 11 were the most active (IC 50  > 0.0001 M). Compounds 1 and 3 showed the best antioxidant activities (45.5 and 55.8 µM); while compounds 9 and 12 showed the best antibacterial activities with MICs values ranges from 8.55 to 132 µM., (© 2020 Walter de Gruyter GmbH, Berlin/Boston.)

Bridelia atroviridis Müll. Arg. (B. atroviridis ) is a plant used in Cameroonian traditional medicine to manage diabetes. The effects of hydroethanolic barks extract from B. atroviridis were evaluated on diabetes disorders including hematology, inflammatory, and oxidative stress parameters. The in vitro antioxidant capacity of the hydroethanolic bark extract (70 : 30) was evaluated. Nicotinamide-/streptozotocin-induced diabetic rats were daily treated with the B. atroviridis extract for fifteen days. Glycemia were evaluated every 5 days, insulin sensibility test was performed, and haematological, inflammatory, and oxidative stress parameters were analysed. Histomorphometry of the pancreas was realized. The extract was able to scavenge free radicals in vitro and decrease significantly the blood glucose levels. The treatment resulted in a significant alleviation of insulin resistance, anemia, leukocytopenia, and thrombocytopenia observed in untreated diabetic rats. The extract significantly decreased proinflammatory cytokines TNF- α , IL-1 β , and IL-10. The rate of reduced glutathione was increased in the pancreas, whereas the catalase activity and nitrite concentration were decreased. Diabetic control showed a reduced size of Langerhans islet, whereas the size of islets was large in treated groups. The hydroethanolic extract of B. atroviridis was able to improve glycemia and alleviate haematological and inflammatory parameters disorders observed in diabetic conditions, probably due to its antidiabetic, anti-inflammatory, and antioxidant capacities., Competing Interests: The authors declare that there are no conflicts of interest., (Copyright © 2020 Clarice Noussi Djouwoug et al.)

The MeOH/CH 2 Cl 2 (1:1) extracts of the roots and leaves of Beilschmiedia louisii and B. obscura showed potent antitrypanosomal activity during preliminary screening on Trypanosoma brucei brucei . Phytochemical investigation of these extracts led to the isolation of a mixture of two new endiandric acid derivatives beilschmiedol B ( 1 ) and beilschmiedol C ( 2 ), and one new phenylalkene obscurene A ( 3 ) together with twelve known compounds ( 4 - 15 ). In addition, four new derivatives ( 11a - 11d ) were synthesized from compound 11 . Their structures were elucidated based on their NMR and MS data. Compounds 5 , 6 , and 7 were isolated for the first time from the Beilschmiedia genus. Additionally, the NMR data of compound 4 are given here for the first time. The isolates were evaluated for their antitrypanosomal and antimalarial activities against Tb brucei and the Plasmodium falciparum chloroquine-resistant strain Pf3D7 in vitro, respectively. From the tested compounds, the mixture of new compounds 1 and 2 exhibited the most potent antitrypanosomal activity in vitro with IC 50 value of 4.91 μM.

Two new ergostane-type steroids named tiamenones A and B (1-2) were isolated from the bark of Entandrophragma angolense (Meliaceae) along with ten known compounds identified as 20S-hydroxy-4,6,24(28)-ergostatrien-3-one (3), 3β,7α,20β-trihydroxyergosta-5,24(28)-diene (4), 3β,5α-dihydroxyergosta-7,22-diene (5), stigmasterol, β-sitosterol, β-amyrin, oleanolic acid, asperphenamate, sucrose and daucosterol. The structures of the isolated compounds have been established using NMR spectroscopic and mass spectrometric analyses. The assignment of relative and absolute configurations of compound 1 was achieved by a NOESY experiment and comparison of its NMR data with those of known compound reported in literature. Compounds 1-3, β-amyrin and asperphenamate were evaluated for their antibacterial potencies against five bacterial model strains viz. Escherichia coli DSMZ 1058, Pseudomonas agarici DSMZ 11810, Bacillus subtilis DSMZ 704, Micrococcus luteus DMSZ 1605 and Staphylococcus warneri DSMZ 20036 and their cytotoxicity on two cell lines KB3-1 and HT-29. No potencies were exhibited by the tested compounds even at the highest concentration of 0.5 mg/mL. Compounds 1-3 were found to be potential HIV-1 inhibitors based on their molecular docking analyses., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Three previously undescribed indole alkaloids, named latifolianine A ( 1 ) and latifoliaindoles A and B ( 2 and 3 ), along with 10 known compounds ( 4 - 13 ), were isolated from the heartwood of Nauclea latifolia . Their structures were elucidated based on the analysis of their NMR and MS data. Latifolianine A ( 1 ) represents an unusual and unprecedented monoterpene indole alkaloid unit condensed with an ursane-type pentacyclic triterpenoid moiety. Plausible biogenetic routes toward latifolianine A ( 1 ) and latifoliaindoles A and B ( 2 and 3 ) were proposed. All the isolates were assessed in vitro for their inhibitory effects on Haemophilus influenzae . Naucleidinal ( 7 ) exhibited potent antibacterial activity (MIC value of 3.1 μg/mL) as compared to a reference drug, ciprofloxacin (MIC value of 1.6 μg/mL).

Urease enzyme (UE) has been reported to be a potent virulence factor for Helicobacter pylori (HP) bacteria indicated to be responsible for various gastrointestinal diseases. Therefore, the spread of HP, currently regarded by the World Health Organization as a class 1 carcinogen, could be better controlled by targeting UE. It is in this line that we have synthesized three new derivatives (2-4) of the naturally occurring olean-12-en-3-one (1), which was previously isolated from the figs of Ficus vallis-choudae Delile (Moraceae). Among the synthesized compounds, 3 and 4 contain an indole moiety. Their structures were unambiguously assigned by spectroscopic and spectrometric techniques (1D-NMR, 2D-NMR and MS). The starting material and the synthesized compounds were screened for UE inhibition activity, and showed significant activities with IC 50 values ranging from 14.5 to 24.6 μM, with compound (1) being the most potent as compared to the positive control thiourea (IC 50  = 21.6 μM). Amongst the synthetic derivatives, compound 4 was the most potent (IC 50  = 17.9 μM), while the others showed activities close to that of the control. In addition, molecular docking study of target compounds 2-4 was performed in an attempt to explore their binding mode for the design of more potent UE inhibitors.

There is continuing need for new and improved drugs to tackle malaria, which remains a major public health problem, especially in tropical and subtropical regions of the world. Natural products represent credible sources of new antiplasmodial agents for antimalarial drug development. Endophytes that widely colonize healthy tissues of plants have been shown to synthesize a great variety of secondary metabolites that might possess antiplasmodial benefits. The present study was carried out to evaluate the antiplasmodial potential of extracts from endophytic fungi isolated from Symphonia globulifera against a chloroquine-resistant strain of Plasmodium falciparum (PfINDO ). Sixty-one fungal isolates with infection frequency of 67.77% were obtained from the bark of S. globulifera . Twelve selected isolates were classified into six different genera including Fusarium , Paecilomyces , Penicillium , Aspergillus , Mucor, and Bipolaris . Extracts from the 12 isolates were tested against PfINDO , and nine showed good activity (IC 50 < 10 &mu;g&middot;mL &minus;1 ) with three fungi including Paecilomyces lilacinus (IC 50 = 0.44 &mu;g&middot;mL &minus;1 ), Penicillium janthinellum (IC 50 = 0.2 &mu;g&middot;mL &minus;1 ), and Paecilomyces sp. (IC 50 = 0.55 &mu;g&middot;mL &minus;1 ) showing the highest promise. These three isolates were found to be less cytotoxic against the HEK293T cell line with selectivity indices ranging from 24.52 to 70.56. Results from this study indicate that endophytic fungi from Symphonia globulifera are promising sources of hit compounds that might be further investigated as novel drugs against malaria. The chemical investigation of active extracts is ongoing.

Background : Pathogenic yeasts resistance to current drugs emphasizes the need for new, safe, and cost-effective drugs. Also, new inhibitors are needed to control the effects of enzymes that are implicated in metabolic dysfunctions such as cancer, obesity, and epilepsy. Methods: The anti-yeast extract from Terminalia mantaly (Combretaceae) was fractionated and the structures of the isolated compounds established by means of spectroscopic analysis and comparison with literature data. Activity was assessed against Candida albicans , C. parapsilosis and C. krusei using the microdilution method, and against four enzymes of metabolic significance: glucose-6-phosphate dehydrogenase, human erythrocyte carbonic anhydrase I and II, and glutathione S -transferase. Results: Seven compounds, 3,3'-di- O -methylellagic acid 4'- O -α-rhamnopyranoside; 3- O -methylellagic acid; arjungenin or 2,3,19,23-tetrahydroxyolean-12-en-28-oïc acid; arjunglucoside or 2,3,19,23-tetrahydroxyolean-12-en-28-oïc acid glucopyranoside; 2α,3α,24-trihydroxyolean-11,13(18)-dien-28-oïc acid; stigmasterol; and stigmasterol 3- O -β-d-glucopyranoside were isolated from the extract. Among those, 3,3'-di- O -methylellagic acid 4'- O -α-rhamnopyranoside, 3- O -methylellagic acid, and arjunglucoside showed anti-yeast activity comparable to that of reference fluconazole with minimal inhibitory concentrations (MIC) below 32 µg/mL. Besides, Arjunglucoside potently inhibited the tested enzymes with 50% inhibitory concentrations (IC 50 ) below 4 µM and inhibitory constant (Ki) <3 µM. Conclusions: The results achieved indicate that further SAR studies will likely identify potent hit derivatives that should subsequently enter the drug development pipeline.

Phytochemical investigation of the methanol extract of Cyphostemma adenocaule liana (bark and wood) led to the isolation of two new ceanothane-type triterpenoids, cyphostemmic acid A 1 and cyphostemmic acid B 2, together with the known triterpenoids 3-7, β-sitosterol and its glucoside. The structures of the isolated compounds were established by 1D- and 2D-NMR spectroscopy. Ozonolysis of cyphostemmic acid A 1, epigouanic acid A 3 and betulin 6 yielded semisynthetic derivatives, cyphostemmic acid C 8, cyphostemmic acid D 9, and 3β,28-dihydroxy-30-norlupan-20-one 10 respectively. Compounds 1-4, 6, 8-10 were tested in vitro, for their antiplasmodial activity against Plasmodium falciparum 3D7 strain and showed weak activity.

The crystal structure of the title compound, C32H39NO4, confirms the absolute configuration of the seven chiral centres in the mol-ecule. The molecule has a 1,1-dimethylprop-2-enyl substituent on the indole nucleus and this nucleus shares one edge with the five-membered ring which is, in turn, connected to a sequence of three edge-shared fused rings. The skeleton is completed by the 7,7-trimethyl-6,8-dioxabi-cyclo-[3.2.1]oct-3-en-2-one group connected to the terminal cyclohexene ring. The two cyclohexane rings adopt chair and half-chair conformations, while in the dioxabi-cyclo-[3.2.1]oct-3-en-2-one unit, the six-membered ring has a half-chair conformation. The indole system of the mol-ecule exhibits a tilt of 2.02 (1)° between its two rings. In the crystal, O-H⋯O hydrogen bonds connect mol-ecules into chains along [010]. Weak N-H⋯π inter-actions connect these chains, forming sheets parallel to (10-1).

Phytochemical investigation of the stem bark extract of Crossopteryx febrifuga resulted in the isolation of epimeric mixtures of 3β-urs-12,20(30)-diene-27,28-dioic acid and 18-epi-3β-urs-12,20(30)-diene-27,28-dioic acid (1), as well as: 3β-D-glucopyranosylurs-12,20(30)-diene-27,28-dioic acid and 18-epi-3β-D-glucopyranosylurs-12,20(30)-diene-27,28-dioic acid (2), together with some known compounds such as the monoglyceride of palmitic acid, as well as β-sitosterol and its glucoside. The structures of the isolated compounds were determined by application of spectroscopic methods. The MeOH extract and compounds 1 and 2 were examined for antimicrobial activity in in vitro assays against bacteria (Enterobacter aerogenes ATCC13048, Escherichia coli ATCC8739, Klebsiella pneumoniae ATCC11296, Staphylococcus aureus) and fungi (Candida parapsilosis, Candida albicans ATCC 9002 and Cryptococcus neoformans IP 90526). The tested samples showed selective activities. The antibacterial and antifungal activities of compound 2 (MIC=8-64 μg/mL) were in some cases equal to or even higher than those of the respective reference drugs chloramphenicol (MIC=16- 64 μg/mL) and nystatin (MIC=128-256 μg/mL).

The title compound, C24H31NO3 {systematic name: (E)-3-[(1R*,2S*,4aS*,8aR*)-2-(benzo[d][1,3]dioxol-5-yl)-1,2,4a,5,6,7,8,8a-octa-hydro-naphthalen-1-yl]-N-iso-butyl-acryl-amide}, is a natural product isolated from the stem bark of B. obscura. It is composed of an octa-hydro-naphthalene ring system substituted with an essentially planar benzodioxole ring system [r.m.s. deviation = 0.012 Å] and an extended iso-butyl-acryl-amide group. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, forming chains propagating along [100]. The chains are linked by pairs of C-H⋯O hydrogen bonds, involving inversion-related benzodioxole ring systems, forming ribbons lying parallel to (010). There are also C-H⋯π inter-actions present within the ribbons.

Plants of the Lauraceae family are widely used in traditional medicine and are sources of various classes of secondary metabolites. Two genera of this family, Beilschmiedia and Endiandra, have been the subject of numerous investigations over the past decades because of their application in traditional medicine. They are the only source of bioactive endiandric acid derivatives. Noteworthy is that their biosynthesis contains two consecutive non-enzymatic electrocyclic reactions. Several interesting biological activities for this specific class of secondary metabolites and other constituents of the two genera have been reported, including antimicrobial, enzymes inhibitory and cytotoxic properties. This review compiles information on the structures of the compounds described between January 1960 and March 2015, their biological activities and information on endiandric acid biosynthesis, with 104 references being cited.

Phytochemical investigation of a dichloromethane-methanol (1:1) extract of the fruit pericarp of Omphalocarpum procerum which exhibited antiplasmodial activity during preliminary screening led to the isolation of the new fatty ester triterpenoid 3β-hexadecanoyloxy-28-hydroxyolean-12-en-11-one (1), together with five known compounds 2-6. The structure of the new compound as well as those of the known compounds was established by means of spectroscopic methods and by comparison with previously reported data. Compounds 1- 4 were evaluated in-vitro for their cytotoxicity against L6 cell lines and antiprotozoal activities against Plasmodium falciparum, Leishmania donovani, Trypanosoma brucei rhodesiense and Trypanosoma cruzi (species responsible for human malaria, visceral leishmaniasis, African trypanosomiasis and Chagas disease, respectively). The tested compounds showed weak to moderate antiprotozoal activity and, no significant effect was detected regarding their cytotoxic potency.