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Five previously undescribed compounds, including three 12-nor-rotenoids, were isolated from Pachyrhizus erosus seeds. A brief survey on the dealkylation of selected rotenoids with BBr 3 was undertaken. Spectroscopic data of these previously undescribed compounds and reaction products are reported. The proposal of absolute configurations at stereocenters in the isolates and reaction products was based on NMR and ECD data. Most of the isolates and reaction products were evaluated for their growth inhibitory activities against four cancer cell lines and a Vero cell line. Many compounds exhibited strong to moderate activities with IC 50 values ranging from 0.06 to 20.9 μM, and their structure-activity relationships were evaluated., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Three undescribed compounds including two furosteroid glycosides (perfoloside and 22-O-methylperfoloside) and one stilbenedimer (perfolostilbene) together with 21 known compounds were isolated from the roots of Smilax perfoliata. The structural elucidation was established by extensive uses of HRMS, 1D and 2D spectroscopic techniques. The assignment of the stereocenters in perfolostilbene was based on NOESY data and ECD calculation. Among the isolates, two compounds showed marginal cytotoxic activity against KB and Hela cell lines while seven stilbenoids showed strong to weak antiacetylcholinesterase and antibutyrylcholinesterase activities with IC 50 ranging between 2-197 µM.

Chromatographic purification of the CH 2 Cl 2 extract of Myristica fragrans seeds provided 19 known compounds, four dihydrofuran neolignans, licarines A, B and maceneolignans A, B were among the isolates. Prior to hydrogenation, in order to obtain their di- and tetrahydrogenated products, the absolute configuration of these compounds was thoroughly investigated based on their optical rotations and ECD spectra. This report provides evidences concerning the disagreement between the use of an aromatic quadrant rule and time-dependent density function theory calculation for the prediction of the absolute configurations at C-7 and C-8 in these dihydrobenzofuran neolignans. The absolute configurations of licarines A, B and maceneolignans A, B were subsequently redefined. The antimicrobial and cytotoxic activities of the isolates and reduction products of licarines A, B and maceneolignans A, B were also investigated., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Magnetic cerium-doped mesoporous titanium dioxide was synthesized by combining sol-gel method and calcination using tetrabutanate and ammonium cerium nitrate as precursors and Pluronic P123 as a template coating on iron oxide covered with carbon in ethanol. The magnetic Ce-doped catalyst showed only anatase structure with a slight increase in lattice parameters compared to the undoped catalyst. The Ce L-edge X-ray absorption near-edge spectroscopy (XANES) spectra showed Ce, and the cerium substitution doping into titanium dioxide was proposed. Degradation of S-metolachlor in aqueous magnetic photocatalyst suspension followed (pseudo) first-order kinetics in the presence of 0.5 g L of γ-FeO@C@0.16 mol% Ce-mTiO with a half-life of 55.18 ± 1.63 min. Fifteen degradation products were identified, and their transformation routes of the photocatalytic degradation were then proposed. Complementary toxicity assessment of the treated S-metolachlor solution was undertaken with Environment Canada's algal microplate assay measuring growth inhibition (72-h IC) in the freshwater chlorophyte Pseudokirchneriella subcapitata. This test method revealed a significant decrease in toxicity (1.7-fold reduction after 180 min of irradiation treatment), thereby confirming that the by-products formed following photocatalysis would be less harmful from an environmental point of view. Photocatalytic degradation of S-metolachlor thus appears to hold promise as a cost-effective treatment technology to diminish the presence of this herbicide in aquatic systems. [ABSTRACT FROM AUTHOR]

Ten poly-O-acylated β-dihydroagarofuran sesquiterpenoids, siphonagarofurans A-J, were obtained from the fruits of Siphonodon celastrineus using chromatographic techniques. Their structures were elucidated by extensive use of 2-D NMR spectroscopic methods. The absolute configurations of siphonagarofurans A-J were assigned following analysis of calculated and experimental ECD spectra. The absolute configuration of siphonagarofuran A was also confirmed by X-ray crystallographic analysis. Selected compounds were evaluated for their cytotoxic activity against KB, Vero and Hela cell lines with siphonagarofuran J identified as the most active compound, with IC 50 values ranging from 14 to 27 μM., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2020. Published by Elsevier Ltd.)

Ten cardiac glycosides ( 1 - 10 ) including six 20,22-dihydrodigitoxigenin and four gitoxigenin glycosides were isolated from the stems of Vallaris glabra together with six known triterpenoid cinnamates. Spectroscopic data of these previously undescribed compounds are reported. All isolates were evaluated for their growth inhibitory activities against three cancer cell lines, and compound 2 was the most active against KB cells with an IC 50 value of 0.03 ± 0.001 μM. Also, compounds 1 , 3 , 5 , and 6 and the triterpenoid cinnamates 11 - 13 showed inhibitory activity (IC 50 < 10 μM) for one or more of the cell lines used.

A magnetic molecularly imprinted polymer (MMIP) for chloramphenicol was prepared using a surface-imprinted and microwave-heating-induced polymerization method. The surfaces of the magnetic particles were first double-bond functionalized with 3-(trimethoxysilyl)propyl methacrylate (γ-MPS), followed by the copolymerization of 4-vinyl pyridine (4-VP) and trimethylolpropane trimethacrylate (TRIM) in the presence of chloramphenicol as a template and 1,1-azobis(cyclohexane-carbonitrile) (ABCN) as an initiator in a mixture of dimethyl sulfoxide and water with microwave heating at 80°C. The magnetic polymer possesses supraparamagnetic properties and was used to concentrate and cleanup chicken feed extract, followed by chromatographic separation using a Lichrospher®100 RP C8 column and detection with two multi-reaction monitoring transitions at m/z 321→ 152 and m/z 321→ 257. The mean recoveries obtained at two spiking levels were in the range of 94.6-100% The relative intra- and inter-day standard deviations were in the range of 1.4-2.6% and 5.1-5.7%, respectively. The detection limit of the method was 0.12 µg kg -1 . This confirmatory method was successfully applied to determine chloramphenicol in chicken feed samples.

Thirteen cardenolide glycosides (1-13) were isolated from the CH 2 Cl 2 and MeOH extracts of Vallaris glabra leaves. The structures of the new compounds (2-13) were identified by spectroscopic methods, with the absolute configurations of the sugar moieties determined by acid hydrolysis. All compounds were evaluated for their cytotoxic activity against human cervix adenocarcinoma, lung carcinoma, and colorectal adenocarcinoma cell lines. The two most potent compounds [2'-O-acetylacoschimperoside P (1) and oleandrigenin-3-O-α-l-2'-O-acetylvallaropyranoside (2)] exhibited IC 50 values in the range of 0.03-0.07 μM.

Five 12,20-epoxypregnane glycosides (1-3, 5, and 6) and two 11,12-seco-pregnane glycosides (4 and 7) with spirodilactone motifs, as well as spirodilactone cleavage products 8 and 9, were isolated from the stems of Hoya kerrii. The relative configurations of the three related skeletons were supported by ROESY experiments and X-ray crystallographic analyses. The isolates were evaluated for their anti-inflammatory activity based on the inhibition of NO production in RAW264.7 cells, and some showed IC 50 values ranging from 12.6 to 96.5 μM. The most potent compound, 9a, was also examined for its anti-inflammatory mechanism against mRNA expression and was found to down-regulate mRNA expression of iNOS and COX-2 in a dose-dependent manner.

Magnetic cerium-doped mesoporous titanium dioxide was synthesized by combining sol-gel method and calcination using tetrabutanate and ammonium cerium nitrate as precursors and Pluronic P123 as a template coating on iron oxide covered with carbon in ethanol. The magnetic Ce-doped catalyst showed only anatase structure with a slight increase in lattice parameters compared to the undoped catalyst. The Ce L III -edge X-ray absorption near-edge spectroscopy (XANES) spectra showed Ce 3+ , and the cerium substitution doping into titanium dioxide was proposed. Degradation of S-metolachlor in aqueous magnetic photocatalyst suspension followed (pseudo) first-order kinetics in the presence of 0.5 g L -1 of γ-Fe 2 O 3 @C@0.16 mol% Ce-mTiO 2 with a half-life of 55.18 ± 1.63 min. Fifteen degradation products were identified, and their transformation routes of the photocatalytic degradation were then proposed. Complementary toxicity assessment of the treated S-metolachlor solution was undertaken with Environment Canada's algal microplate assay measuring growth inhibition (72-h IC 50 ) in the freshwater chlorophyte Pseudokirchneriella subcapitata. This test method revealed a significant decrease in toxicity (1.7-fold reduction after 180 min of irradiation treatment), thereby confirming that the by-products formed following photocatalysis would be less harmful from an environmental point of view. Photocatalytic degradation of S-metolachlor thus appears to hold promise as a cost-effective treatment technology to diminish the presence of this herbicide in aquatic systems.

This study was performed to identify the degradation products of profenofos "a phenyl organothiophosphate insecticide" in raw water (RW) collected from the entry point of Metropolitan Water Works Authority "Bangkaen, Thailand" and ultrapure water (UPW) with and without TiO 2 under simulated sunlight irradiation. Degradation of profenofos was followed with ultrahigh performance liquid chromatography (UHPLC) and follows pseudo first-order kinetic. Accordingly, high-field FTICR mass spectrometry coupled to an electrospray ionization source was used to reveal the degradation routes of profenofos and the isotopic fine structures (IFS) elucidations to approve the chemical structures of its degradation products. More degradation products were detected in UPW as compared to RW. Consequently, two main degradation pathways namely (i) interactive replacements of bromine and hydrogen by hydroxyl functional groups and (ii) rupture of PO, PS, CBr and CCl bonds were observed. None interactive replacement of chlorine by hydroxyl functional group was detected. Accordingly, mechanistical pathways of the main degradation products were established.

Sixteen compounds including dihydroxy prenylfuranocoumarins/3-hydroxy-3-methylglutaric acid conjugates and dihydroxy prenylfuranocoumarins/3-hydroxy-3-methylglutaric acid/1-O-flavonyl-β-d-glucopyranoside conjugates, together with other dihydroxyprenylfuranocoumarins conjugates, were isolated from the ethyl acetate extract of the fruit peels of Citrus hystrix. Some of the isolates were evaluated for their cholinesterase inhibitory activity, but only one compound possessing a 3-O-β-d-glucopyranosyl-3,5,7,4'-tetrahydroxy-6,8,3'-trimethoxyflavonol nucleus in the prenylfuranocoumarin-HMGA conjugate showed strong activity., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Bromacil (5-bromo-3-sec-butyl-6-methyluracil) is a substituted uracil herbicide used worldwide. It is not readily biodegradable and has the potential to contaminate different types of water bodies with possible impact on diverse non-target species. In this work, degradation of bromacil in aqueous Au/TiO2 suspension under simulated sunlight allowed fourteen degradation products to be identified. The photodegradation of bromacil followed (pseudo) first order kinetics in the presence of 0.2 g L(-1) of Au/TiO2 with a half-life of 25.66 ± 1.60 min and a rate constant of 0.0271 ± 0.0023 min(-1). Transformation routes of the photo-catalytic degradation of bromacil were then proposed. Complementary toxicity assessment of the treated bromacil solution revealed a marked decrease in toxicity, thereby confirming that by-products formed would be less harmful from an environmental point of view. Photo-catalytic degradation of bromacil thus appears to hold promise as a cost-effective treatment technology to diminish the presence of this herbicide in aquatic systems.

Background: Poekilocerus pictus (Fabricius 1771), a painted grasshopper, sequesters cardenolides from its food plant, the Apple of Sodom or Aak, Calotropis procera (Aiton) W.T. Aiton (Family-Asclepiadaceae). In our present investigation, we were able to isolate Pseudomonas aeruginosa KRK6 from the intestine of Poekilocerus pictus responsible for the biotransformation of cardenolides. Methods: Pseudomonas aeruginosa KRK6 was grown in methanolic extracts of Calotropis procera and the modified cardenolides were detected by Liquid Chromatography-Mass Spectrometry (LCMS) and also used to induce apoptosis in cancer cells (MCF-7 cells and T-47 D). Result: The modified cardenolides CPMEP6 was found to induce apoptosis in human breast adenocarcinoma cells (MCF cells-IC50= 6.31±0.4 µg/mL, T-47D cells-IC50= 10.1±1.02 µg/mL). Phosphatidylserine exposure and DNA fragmentation suggested apoptosis in treated cancer cells. CPMEP6 induced apoptosis in cancer cells via the mitochondrial pathway by down-regulating BCL-2 protein expression and up-regulating BAX protein expression. [ABSTRACT FROM AUTHOR]

The Euphorbiaceae family is a rich source of bioactive terpenoids. Among its genera, Jatropha is a conspicuous producer of diterpenes and includes approximately 175 species, many of which have medicinal uses. To date, 140 diterpenes from Jatropha (JTDs) have been reported. Given their structural diversity and notable biological activities, this work aims to highlight the pharmaceutical potential of JTDs. To achieve this goal, an extensive literature review was conducted, encompassing studies on structural elucidation through NMR and pharmacological assays, both in vitro and in vivo. Based on 132 selected papers, a thorough discussion is presented on the biosynthesis, extraction, isolation, and structural characterization of JTDs, including a compilation of their 13C NMR chemical shifts. The review also covers their synthetic production and biological effects. Additionally, an in silico analysis predicting the drug-likeness of 141 JTDs was carried out. Notably, the occurrence of macrocyclic diterpenes has doubled in the past decade, and the summary of their NMR data provides a useful resource for future research. Furthermore, 21 distinct pharmacological activities were identified, with potent cytotoxic effects targeting new molecular pathways being particularly significant. Recent advances highlight the contributions of modern approaches in organic synthesis and the pharmacological evaluation of natural products. The drug-likeness analysis identified JTD classes and compounds with favorable physicochemical and ADMET features for pharmaceutical development. In light of these findings, the use of nanotechnology is proposed as a future direction for continued research on JTDs, a fascinating class of natural compounds. This work opens up new avenues for the study of Euphorbiaceae species, particularly the Jatropha genus and its bioactive compounds. [ABSTRACT FROM AUTHOR]

Background: Galatella is a genus in the family Asteraceae, represented by 35-45 species. Considering the high effectiveness of the ethyl acetate (EtOAc) fraction of G. grimmii against Mycobacterium tuberculosis (MIC = 0.5 µg/mL), a bioassay-directed fractionation of this extract was carried out. Methods: The methanolic extract of the aerial parts of G. grimmii was obtained using maceration, then it was suspended in water and partitioned with petroleum ether, dichloromethane (CH2Cl2), EtOAc, and n-butanol (n-BuOH), successively. The most potent fraction (EtOAc), was selected for further isolation by Sephadex LH–20 and semi-preparative HPLC to obtain active compounds. Results: Fractionation of the EtOAc solvent fraction resulted in the characterization of five compounds, among them, compounds 1 and 2 showed the highest anti-mycobacterial effects with MICs of 0.062 and 1.00 µg/mL against H37Rv M. tuberculosis, respectively, which were higher than those of rifampin (MIC of 1.25 µg/mL) and isoniazid (MIC of 0.31 µg/mL), as positive controls. Also, compound 1 ​​inhibited all tested strains of drug-resistant Mycobacterium (MDR and XDR). Notably, the isolated compounds have been reported for the first time from G. grimmii. Conclusion: Due to the potent anti-mycobacterial effect of isolated compounds from G. grimmii, this study could pave the way for developing a novel class of natural anti-tuberculosis compounds. [ABSTRACT FROM AUTHOR]

Mauritia flexuosa (M. flexuosa), commonly known as Aguaje or Moriche palm, is traditionally recognised in South America for its medicinal properties, particularly for its anti-inflammatory and antioxidant effects. However, the bioactive compounds responsible for these effects have not been thoroughly investigated. This study aims to isolate and characterise pentacyclic triterpenoid compounds from M. flexuosa and to evaluate their therapeutic potential. Using various chromatographic and spectroscopic techniques including Nuclear Magnetic Resonance (NMR) and Mass Spectrometry (MS), three pentacyclic triterpenoid compounds were successfully isolated. Among them, compound 1 (3,11-dioxours-12-en-28-oic acid) exhibited notable bioactivity, significantly inhibiting the activation of Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-κB) (IC50 = 7.39–8.11 μM) and of Nitric Oxide (NO) (IC50 = 4.75–6.59 μM), both of which are key processes in inflammation. Additionally, compound 1 demonstrated potent antioxidant properties by activating the antioxidant enzyme Superoxide Dismutase (SOD) (EC50 = 1.87 μM) and the transcription factor Nuclear factor erythroid 2-related factor 2 (Nrf2) (EC50 = 243–547.59 nM), thus showing its potential in combating oxidative stress. This study is the first to isolate and characterise the three compounds from M. flexuosa, suggesting that compound 1 could be a promising candidate for the development of safer and more effective therapies for inflammatory and oxidative stress-related diseases. [ABSTRACT FROM AUTHOR]

Six prenylated flavonoids, (2R,3S)-3,5,4'-trihydroxy-6″-6″dimethylpyrano(2″,3″:7,6)-8-(3″', 3″'-dimethylallyl)flavanone, (2R,3S)-3,5,2'-trihydroxy-4'-methoxy-6″,6″-dimethylpyrano(2″,3″:7,6)-8-(3″',3″'-dimethylallyl)flavanone, (2R,3R)-3,5,2',4'-tetrahydroxy-6″,6″-dimethylpyrano(2″,3″:7,6)-8-(3″',3″'-dimethylallyl)flavanone, 3,5,2',4'-tetrahydroxy-6″,6″-dimethylpyrano(2″,3″:7,6)-8-(3″',3″'-dimethylallyl)flavone, (2R,3R,2″'R)-3,5,2″'-trihydroxy-4'-methoxy-6″,6″-dimethylpyrano(2″,3″:7,6)-8-(3″'-methylbut-3″'-enyl)flavanone, (2R,3R)-3,5-dihydroxy-4'-methoxy-6″,6″-dimethylpyrano(2″,3″:7,6)-8-(2″',3″'-epoxy-3″'-methyl butyl)flavanone, an isoflavone, 6,7-dimethoxy-5,2',4'-trihydroxyisoflavone, and octaeicosanyl-trans-p-coumarate together with 12 known compounds, were isolated from roots of Eriosema chinense. This structural elucidation was determined by spectroscopic methods. Several isolates and derivatives were evaluated for their antimicrobial and antioxidant activities. Results obtained provide additional evidence showing that the presence of both the free phenolic OH and the lipophilic prenyl groups are crucial for potent antimicrobial activity against yeast, gram positive and gram negative bacteria, whereas the presence of free phenolic OH group is required for strong radical scavenging property., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Phenylurea herbicides have been known to contaminate surface waters serving as potable supplies. To access the potential for transformation of these compounds during drinking water treatment, reactions of phenylurea compounds with aqueous chlorine at different pHs were investigated. The effect of substitution at the amino-N on the rate of transformation depends upon pH. Under acidic conditions, all of the phenylurea studied except 3,4-dichloro-3'-N-methylphenylurea (3,4-DCMPU) exhibited third-order kinetics, second order with respect to chlorine and first order with respect to phenylurea, while the reactions of 3,4-DCMPU were first order with respect to both chlorine and the organic compound. Under neutral and alkaline conditions, all compounds exhibited second-order kinetics that was first order with respect to chlorine and the organic compound. Apparent second-order rate constants at 25°C and pH 7 were 0.76 ± 0.16, 0.52 ± 0.11, 0.39 ± 0.02, 0.27 ± 0.04 and 0.23 ± 0.05 M(-1)s(-1) for phenylurea, 3, 4-dichlorophenylurea, 3, 4-DCMPU, metoxuron and monuron, respectively. Studies of the chlorination products, monitored by LC/MS/MS, under different pH values indicated the reaction to take place at both N atoms and also at ortho- and para- positions of the phenylurea aromatic group. The main chlorinating species were found to be different in different pH ranges. Under conditions typically encountered in drinking water treatment systems, transformation of these compounds by chlorine will be incomplete., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Eight new sesquiterpene alkaloids (1-8) and four known sesquiterpene alkaloids (9-12) have been isolated from the roots of Maytenus mekongensis. Structures were determined using extensive spectroscopic methods. The relative configuration of 7-epi-mekongensine (2) was established by single-crystal X-ray crystallographic analysis. The alkaloids were evaluated for antiplasmodial activity against Plasmodium falciparum, K1 strain, and for cytotoxicity using a panel of cell lines.

Four new compounds, citrusosides A-D (1-4), and 15 known compounds were isolated from the hexanes and CH(2)Cl(2) extracts of the peels of Citrus hystrix fruits. Compound 1 is a 1-O-isopropyl-6-O-β-D-glucopyranosyl ester of 5'',9''-dimethyl-2'',8''-decadienoic acid. Compounds 2-4 possess a 1-O-isopropyl-β-D-glucopyranosyl and a dihydroxyprenylfuranocoumarin moiety conjugated to the 3-hydroxy-3-methylglutaric acid as diesters. Several furanocoumarins were evaluated for their cholinesterase inhibitory activity. (R)-(+)-6'-Hydroxy-7'-methoxybergamottin, (R)-(+)-6',7'-dihydroxybergamottin, and (+)-isoimparatorin showed IC(50) values of 11.2 ± 0.1, 15.4 ± 0.3, and 23 ± 0.2 μM, respectively. Bioassay results indicated that the presence of a dioxygenated geranyl chain in the test compounds is crucial for the inhibitory activity.

Two 15beta-hydroxycardenolides (1,2) and a 16alpha-hydroxycalactinic acid methyl ester (3) along with eleven known compounds including 16alpha-hydroxycalotropagenin, coroglaucigenin, 16alpha-hydroxycalotropin, calactinic acid, calotoxin, 6'-O-(E-4-hydroxycinnamoyl)desglucouzarin, 12beta-hydroxycoroglaucigenin, frugoside, calotropagenin, 9,12,13-trihydroxyoctadeca-10(E),15(Z)-dienoic acid and R-(-)-mevalonolactone were isolated from the polar fraction of the CH(2)Cl(2) extract, and n-BuOH extract of the leaves of this plant. The isolated compounds were evaluated for their inhibitory activities against a panel of cell lines.

Five new compounds, 2alpha-hydroxyjatropholone (1), 2beta-hydroxyjatropholone (2), 1,5-dioxo-2,3-dihydroxyrhamnofola-4(10),6,11(18),15-tetraene (3), 2-keto-5-hydroxyguai-3,11-diene (4), and a sesquiterpene-coumarin conjugate, jatrophadioxan (5), and nine known compounds have been isolated from the roots of Jatropha integerrima. The structures were established from spectroscopic data, and the relative configuration of 1 was confirmed by X-ray crystallography. Six diterpenes were evaluated for their antiplasmodial, antituberculosis, and cytotoxic activities.

Two new acetylenic fatty acids (1, 2), a new triglyceride (3), along with eleven known compounds including 3-oxo-11alpha,12alpha-epoxyurs-13beta,28-olide (4) previously reported as a synthetic compound, have been isolated from the leaves of Hymenodictyon excelsum. The structural identification was established from spectroscopic data.

Eight new prenylated flavonoids, khonklonginols A-H (1-8), together with six known compounds including five flavonoids, lupinifolinol (9), dehydrolupinifolinol (10), flemichin D (11), eriosemaone A (12), and lupinifolin (13), and one lignan, yangambin (14), have been isolated from hexane and dichloromethane extracts of the roots of Eriosema chinense. The structures of 1-8 were elucidated by spectroscopic methods. The compounds were evaluated for cytotoxic activity against the small-cell lung (NCI-H187) and oral epidermal carcinoma (KB) human cell lines as well as for antimycobacterial activity against Mycobacterium tuberculosis H37Ra.

The synthesis of derivatives of metabolites from furazolidone, furaltadone, nitrofurazone, and nitrofurantoin using a new derivatizing reagent, 2-naphthaldehyde (NTA), is described. The reaction product was used in liquid chromatography with diode array detector (LC-DAD) for determination of protein-bound metabolites of nitrofurans in shrimp followed by two steps of liquid-liquid extraction. Derivatives of nitrofuran metabolites are well separated from NTA remaining in the extract upon separation on a ChromSpher 5 Pesticide (250 x 4.6 mm, 5 microm) column at 40 degrees C with acetonitrile/5 mM ammonium acetate adjusted to pH 7.5 gradient as the mobile phase and DAD detection at 308 nm except for naphthyl derivative of 1-aminohydantoin at 310 nm. The high absorptivity of these derivatives makes simultaneous screening of these metabolites in shrimp at 1 microg/kg possible for the first time using LC-DAD. The method was validated using blank shrimp fortified with all four metabolites at 1, 1.5, and 2 microg/kg. Recoveries were >86% with relative standard deviations of <14% for all four metabolites. Comparison between LC-DAD and APCI-MS/MS shows very good agreement for shrimp samples.

Six new poly-O-acylated jatrophane diterpenes (1- 6) have been isolated along with five known compounds from the white latex of Pedilanthus tithymaloides. The structural identification was accomplished on the basis of 2D NMR and MS investigations. Some of these highly oxygenated jatrophane diterpenes possess a rare O-acetyl enol moiety. Compounds 1 and 3- 5 showed antiplasmodial activity with IC(50) values of 3.4-4.4 microg/mL and antimycobacterial activity against Mycobacterium tuberculosis with minimum inhibition concentration (MIC) values ranging from 12.5 to 100 microg/mL.

Coumarin derivatives are naturally and synthetically derived compounds and are considered one of the most versatile classes of heterocycles. Discovering, synthesizing, and examining coumarin derivatives for several biological activities are a constant endeavor due to their pharmacological activities, high selectivity, simple design to achieve optimal efficiency, and few side effects. Coumarin gained notable attention and became such a privileged scaffold and promising building block for the development of different medical agents for the treatment of various diseases. The scientists are continuously trying to synthesize many bioactive coumarins by either improving existing ones or exploring novel-based natural products. The gathering of two or more heterocyclic nuclei in one molecule can potentiate the pharmacological effects of the resulting system or even create new pharmacological properties. When different heterocycles are attached to coumarin either as a substituent or as a fused component into a lactone or benzene ring, a synergistic or additive effect has been observed in many studies. The present article delves deeply into the pharmacological potential, structure–function correlations, natural sources, and synthetic techniques of heterocycles fused on a 6,7-coumarin framework. The authors searched several stores of data, including Scopus, Google Scholar, PubMed, Web of Science, and PubMed. Following a deep evaluation, authors were able to locate and include 189 relevant papers that were released from 2000 to mid-2023. Medicinal chemists may be enabled to use this reviewed information to develop and synthesize biologically active leads based on heterocycles fused on 6,7-coumarin scaffolds. The knowledge built from this information may have significant medicinal advantages in the not-so-distant future to develop potent medication, serving better in therapeutics. [ABSTRACT FROM AUTHOR]

Twelve polyoxygenated cyclohex(a/e)ne diterpene esters, named albiflorenes A–L (1–12), were isolated from the whole plants of Kaempferia albiflora, known as "Prao Mang Mum." Their structures and relative stereochemistry were determined by extensive spectroscopic analysis. Furthermore, the comparison of experimental electronic circular dichroism (ECD) curves with the curves predicted by TDDFT was used to determine the absolute configurations. Albiflorenes contain polyoxygenated cyclohexane (or cyclohexene) derivatives, which are linked to either isopimarane or abietane diterpene acid units. The discovery marks the first occurrence of a conjugate between polyoxygenated cyclohexane (or cyclohexene) rings and diterpenoids. Among the isolates, albiflorene C specifically exhibited antibacterial activity against Bacillus cereus with MIC and MBC values of 3.13 and 6.25 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

Two new cyclic heptapeptides, integerrimides A and B, have been isolated from the latex of Jatropha integerrima. Their structures were elucidated by using extensive 1D and 2D NMR, MS, and chemical degradation. At 50 microM both peptides 1 and 2 significantly inhibited neurite outgrowth in neuronal cell culture. They also partially inhibited proliferation of human IPC-298 melanoma cells as well as migration of human Capan II pancreatic carcinoma cells, but were inactive in HSV-1, antifungal, and antimalarial assays.

Two new cardenolides (1 and 2) along with 12 known compounds were isolated from the dichloromethane extract of the leaves of Calotropis gigantea. The structural elucidation was accomplished by spectroscopic methods. Some of the isolates were evaluated for cytotoxic activity against KB, BC, and NCI-H187 cancer cell lines, and all cardenolides tested were found to possess strong inhibitory effects. The presence of a deoxysugar at C-3, a formyl group at C-10, and an alpha,beta-unsaturated gamma-lactone was crucial for cytotoxic activity.

A dichloromethane extract of the leaves of Phyllanthus polyphyllus var. siamensis afforded two new monoacetylated triterpene arabinosides (1 and 2) and 15 known compounds. The structures of the new compounds were elucidated on the basis of spectroscopic data interpretation. The isolates and some chemical transformation products were evaluated biologically, and the presence of an arabinosyl moiety among the hederagenin glycosides evaluated was found to be important for the modulation of cytotoxic activity against cancer cells.

From the leaves of Macaranga tanarius, three new constituents, tanarifuranonol (1), tanariflavanone C (2), and tanariflavanone D (3), together with seven known compounds, were isolated and identified. Substances obtained in this investigation were evaluated against a panel of bioassays.

Three new D:A-friedo-oleanane lactones, viz., 3-oxo-D:A-friedo-oleanan-27,16alpha-lactone (1), 3alpha-benzoyloxy-D:A-friedo-oleanan-27,16alpha-lactone (2), and 3beta-hydroxy-D:A-friedo-oleanan-27,16alpha-lactone (3) were isolated from the stems of Mallotus repandus. Extensive use of NMR spectroscopic techniques led to full assignment of all 1H and 13C chemical shifts. The structure for 2 was confirmed by X-ray diffraction analysis.

From the chloroform extract of the leaves of Croton joufra, the diterpenes 2alpha,3alpha-dihydroxy-labda-8(17),12(13),14(15)-triene and 3beta-hydroxy-19-O-acetyl-pimara-8(9),15-dien-7-one, were isolated. Their structures were established by spectroscopic methods. One of the compounds showed weak lethality in the brine shrimp assay.