Anti-glycating and anti-oxidant compounds from traditionally used anti-diabetic plant Geigeria alata(DC) Oliv. & Hiern.

Abstract

A new sesquiterpene lactone geigerianoloide (1) and four known flavonoids axillarin (2), quercetin (3), 3-methoxy-5,7,3',4'-tetrahydroxy-flavone (4) and hispidulin (5) were isolated from Geigeria alata (DC) Oliv. & Hiern. (Asteraceae). Structures were deduced using ¹H- and ¹³C- NMR spectroscopy, mass spectrometry, while the structure of compound 1 was also deduced using X-ray crystallography technique.

Geigeria alata is traditionally used for diabetes, therefore compounds were tested for anti-glycation activity, in which compounds 2 and 3 showed potent activities (IC₅₀ values of 246.97?±?0.83 and 262.37?±?0.22 µM, respectively) compared to IC₅₀ value 294.50?±?1.5 µM of rutin. Moreover, compound 4 exhibited a comparable activity to rutin (IC₅₀?=?293.28?±?1.34 µM). Compound 5 showed a weak activity.

Compounds 2, 3, and 4 exhibited potent DPPH radical scavenging activity (IC₅₀?=?0.1?±?0.00, 0.13?±?0.00 and 0.15?±?0.01 µM, respectively). Compounds 2, 3, and 4 demonstrated significant superoxide anion scavenging activity with IC₅₀ values of 0.14?±?0.001, 0.17?±?0.00, and 0.11?±?0.006 µM, respectively.     

An unreported bis-abeo cembrane-type diterpenoid with antioxidative and anti-lipoxygenase activities from the muricid gastropod mollusc Chicoreus ramosus

Abstract

The chemical analyses of ethyl acetate-methanol (EtOAc-MeOH) extract of muricid gastropod mollusk, Chicoreus ramosus from the southeastern coast of Indian peninsular led to the identification of unprecedented cembrane-type diterpenoid, which was characterized as (3E, 6E, 10E)-8a-butoxy-17(15→14), 20(12→11)-bis-abeo-cembra-3,6,10,14(17),15-pentaene (1). The structure of the studied cembrane was unambiguously assigned through the extensive spectroscopic experimentations. The antioxidant potentials of the bis-abeo cembrane as determined by in vitro 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis-3-ethylbenzothiozoline-6-sulfonic acid diammonium salt radical quenching potentials were greater (IC₅₀?<?0.40?mg/mL) related to α-tocopherol (IC₅₀?>?0.60?mg/mL). The pro-inflammatory anti-5-lipoxygenase potential of studied cembrane was higher (IC₅₀?<?0.80?mg/mL) related to those demonstrated by ibuprofen and sodium salicylate (IC₅₀?>?0.90?mg/mL).     

Chemical characterization of constituents from Polygonatum cyrtonema Hua and their cytotoxic and antioxidant evaluation

Abstract

Twenty-four compounds were isolated from the roots of Polygonatum cyrtonema Hua, including a new octopamine dimer, named trans-bis(N-feruloyl)octopamine (1). The structure was established on the basis of spectroscopic and chemical methods. All the extracts and compounds were evaluated for cytotoxic and antioxidant activities by using MTT and chemiluminescence assay. The extracts showed activity against MCF-7 and HepG-2 cell lines from IC₅₀ 0.30 to 1.01 mg mL^?1. Compound 3 exhibited activity against HepG-2 cell lines with IC₅₀ 8.99?μM. Compound 7 exhibited activity against Hela cell lines with IC₅₀ 2.53?μM and BGC-823 cell lines with IC₅₀ 7.77?μM. Moreover, compound 7 showed antioxidant with IC₅₀ 12?µM compared to the positive control with IC₅₀ 77?µM. Compound 16 exhibited activity against HepG-2 cell lines with IC₅₀ 1.05?μM and MCF-7 cell lines with IC₅₀ 1.89?μM. These results indicated that this plant might be potential in natural medicine and healthy food.     

Previously undescribed benzoxepins with bioactivities against inducible pro-inflammatory cyclooxygenase and lipoxygenase from Rhizophora annamalayana Kathir

Two unprecedented benzoxepins were obtained from the ethyl acetate fraction of the leaves of Rhizophora annamalayana Kathir, and characterized as 4-(11-(hydroxymethyl)-10-methylpentan-2-yl)-4, 5-dihydrobenzo[c]oxepin-1(3H)-one (1) and (E)-methyl-14-hydroxy-4-(11-(5-hydroxy-1-oxo-3,4,5-tetrahydrobenzo[c]oxepin-4-yl)ethyl)-10-methylhept-11-enoate (2). The benzoxepin 2 exhibited greater 1, 1-diphenyl-2-picrylhydrazyl and 2, 2′-azino-bis-3 ethylbenzothiozoline-6-sulfonic acid diammonium radical scavenging assays (IC₅₀ 0.68 and 0.84 mg/mL, respectively) than those recorded with 1 (IC₅₀ 0.70 and 0.89 mg/mL, respectively). The tetrahydrobenzo[c]oxepin analogue (2) exhibited significantly great cyclooxygenase-2 and 5-lipoxygenase inhibitory properties (IC₅₀ 0.87 and 0.94 mg/mL, respectively), while compared with its dihydrobenzo[c]oxepin-1(3H)-one isoform (1) (IC₅₀ 1.16 and 1.64 mg/mL, respectively). The dihydrobenzo[c]oxepin-1(3H)-one isoform (2) exhibited significantly greater selectivity index (~2) than synthetic ibuprofen (0.44) (p < 0.05), which attributed the higher anti-inflammatory selectivity of the former against inducible pro-inflammatory cyclooxygenase-2 than its constitutive isoform (cyclooxygenase-1). No significant difference in 5-lipoxygenase (5-LOX) inhibitory activities were apparent between compound 2 (IC₅₀ 0.94 mg/mL) and synthetic ibuprofen (IC₅₀ 0.93 mg/mL).     

Urease inhibitory profile of extracts and chemical constituents of Pistacia atlantica ssp. cabulica Stocks

The current study was designed to evaluate the urease inhibitory profile of extract and fractions of Pistacia atlantica ssp. cabulica Stocks followed by bioactivity-guided isolated compounds. The crude extract was found significantly active with urease inhibitor (95.40% at 0.2 mg/mL) with IC₅₀ values of 32.0 ± 0.28 μg/mL. Upon fractionation, ethyl acetate fraction displayed 100% urease inhibition with IC₅₀ values of 19.9 ± 0.51 μg/mL at 0.2 mg/mL. However, n-hexane and chloroform fractions exhibited insignificant urease inhibition. Similarly, the isolated compound, transilitin (1) and dihydro luteolin (2) demonstrated marked urease attenuation with 95 and 98% respectively, at 0.15 mg/mL. Both the isolated compounds showed marked potency with IC₅₀ values of 8.54 ± 0.54 and 9.58 ± 2.22 μg/mL, respectively. In short, both the extract and fractions and isolated compounds showed marked urease inhibition and thus a useful natural source of urease inhibition.     

Reaction of 2-imino-2H-chromene-3-carboxamide with some phosphorus esters: Synthesis of some novel chromenes containing phosphorus heterocycles and phosphonate groups and their antioxidant and cytotoxicity properties

Abstract

Novel chromenyl α-aminophosphonic acid 4 and dialkyl chromenyl phosphonate 6 have been obtained. In addition, some novel types of chromene fused with phosphorus heterocycles such as chromeno[4,3-c][1,2]azaphospholes 5 and 7, chromeno[2,3-d][1,3,2]diazaphosphinine 8 and 1,2-oxaphosphinino[3,4-c]pyridine 10 have been synthesized. The methodology depended on treatment of 2-imino-2H-chromene-3-carboxamide (1) with some phosphorus esters. The synthesized compounds were evaluated for antioxidant and cytotoxic activities. Among the synthesized compounds, compound 5 exhibited the most antioxidant activity with IC₅₀ = 2.8?μg/mL in comparison with ascorbic acid as standard antioxidant. Also, compound 5 had significant cytotoxic effects against four cancer cell lines. Its IC₅₀ values ranged between 4.96 and 7.44?μg/mL in comparison to doxorubicin (IC₅₀ = 0.426–0.493?μg/mL).     

GC-MS analysis of metabolites from soxhlet extraction,ultrasound-assisted extraction and supercritical fluid extraction of Salacca zalacca flesh and its alpha-glucosidase inhibitory activity

Abstract

Different extraction processes were employed to extract bioactive metabolites from Salacca zalacca flesh by a range of aqueous and organic solvents. The highest extraction yield was obtained by 50% ethanol extract of SE (73.18?±?4.35%), whereas SFE_1 showed the lowest yield (0.42?±?0.08%). All extracts were evaluated for in vitro α-glucosidase inhibitory activity, measured by their IC₅₀ values in comparison to that of quercetin, the positive control (IC₅₀ = 2.7?±?0.7?μg/mL). The lowest α-glucosidase inhibitory activity was indicated by water extract of SE (IC₅₀ = 724.3?±?42.9?μg/mL) and the highest activity was demonstrated by 60% ethanol extract by UAE (IC₅₀ = 16.2?±?2.4?μg/mL). All extracts were analysed by GC-MS and identified metabolites like carbohydrates, fatty acids, organic acids, phenolic acids, sterols and alkane-based compounds etcetera that may possess the potential as α-glucosidase inhibitor and may attribute to the α-glucosidase inhibitory activity.     

First report of anti-inflammatory chromenyl derivatives from the spineless cuttlefish Sepiella inermis

Abstract

The spineless cuttlefish Sepiella inermis encompasses a major share in the marine fisheries sector, and represents as a culinary delicacy in many cultures. Bioactivity-guided fractionation of methanol:ethyl acetate (MeOH:EtOAc, 1:1) extract of the edible parts of the species ensued in identification of two hexahydro chromenyl analogues namely, methyl 7-ethyl-hexahydro-8a-methyl-2H-chromene-4-carboxylate (1) and methyl 1-acetoxy-hexahydro-3-methyl-3-propyl-1H-isochromene-4-carboxylate (2). The isolated metabolites were checked for their radical scavenging and anti-inflammatory potentials by selective in vitro models. The isochromenyl derivative exhibited potential 2,2-diphenyl-1-picryl-hydrazil and 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (IC₅₀?<?0.45?mg mL^?1) radical-scavenging capacities along with pro-inflammatory cyclooxygenase-2 (COX-2) (IC₅₀ 0.75?mg mL^?1) and 5-lipoxygenase (5-LOX) (IC₅₀ 0.77?mg mL^?1) inhibitory activities. The titled compounds displayed the selectivity indices (IC₅₀ anti-COX-1/IC₅₀ anti-COX-2) greater than 1.25, in comparison with synthetic anti-inflammatory drug ibuprofen (0.44), which attributed to their greater selectivity towards inducible pro-inflammatory enzyme COX-2.     

Synthesis,characterization, and hypoglycemic efficacy of nitro and amino acridines and 4-phenylquinoline on starch hydrolyzing compounds: an in silico and in vitro study

α-Amylase and α-Glucosidase are important therapeutic targets for type II diabetes. The present focus of our study is to elucidate the hypoglycemic activity of novel compounds through in vitro and in silico studies. Here, we synthesized the nitro acridines (3a–3c), amino acridines (4a–4c), and nitro phenylquinoline (3d) and amino phenylquinoline (4d) using a multi-step reaction protocol in good yields. All the above derivatives were screened for molecular docking, α-Amylase and α-Glucosidase inhibitory activities utilizing acarbose as standard drug. In silico studies were performed to explore the binding ability of compounds with the active site of α-Amylase and α-Glucosidase enzymes. The in vitro antihyperglycemic report of 3c exhibits the maximum inhibitory activity with IC₅₀ values of 200.61?±?9.71 μmol/mL and 197.76?±?8.22 μmol/mL against α-Amylase and α-Glucosidase, respectively. Similarly, the compound 3a exhibits IC₅₀ values of 243.78?±?13.25 μmol/mL and 296.57?±?10.66 μmol/mL, and 4c exhibits IC₅₀ values of 304.28?±?3.51 μmol/mL and 278.86?±?3.24 μmol/mL with a significant p?<?0.05 in both enzyme inhibitions. In addition, the presence of diverse functional moieties in synthesized compounds may provide a strong inhibitory action against the abovementioned enzymes compared with standard acarbose inhibition (IC₅₀, 58.74?±?3.68 μmol/mL and 49.39?±?4.94 μmol/mL). Also, the docking studies provided an excellent support for our in vitro studies. The outcome of these studies recommends that the tested compounds might be treated as potential inhibitors for the starch hydrolyzing enzymes in type II diabetes.

     

Synthesis of spirooxindoles promoted by the deep eutectic solvent,ZnCl2+urea via the pseudo four-component reaction: anticancer,antioxidant, and molecular docking studies

Abstract

Various spirooxindoles (7a–c, 8a–c, 9a–c, and 10a–c) were efficiently synthesized using deep eutectic solvent ZnCl₂+urea and well characterized using IR, ¹H NMR, and ¹³C NMR spectroscopic techniques. The biological screening results showed that the compound 9a exhibited potent anticancer activity against MCF7 and HeLa cell lines with IC₅₀ values 6.47?±?0.01 and 9.14?±?0.32?µM, respectively. The compound 7c exhibited potent activity against the HeLa cell line with IC₅₀ value 6.81?±?0.01?µM. The compound 9a exhibited a potent antioxidant activity with IC₅₀ value 7.34?±?0.17?µM. The comparative molecular docking study against the cancer proteins EGFR and HER2 revealed that the EGFR was the best target protein receptor for the target compounds. Among all the compounds, the compound 9a exhibited the least binding energy ?10.72?kcal/mol against the protein EGFR (PDB ID: 4HJO).     

Xanthones from a lignicolous freshwater fungus (BCC 28210)

Abstract

Four xanthones (1?4) and a known compound, mansonone D (5), were isolated from the lignicolous freshwater fungus BCC 28210 (family, Chaetosphaeriaceae). The structures of these compounds were elucidated by extensive spectroscopic analysis. Among the isolated metabolites, compound 2 and the known mansonone D (5) displayed antimalarial activity against Plasmodium falciparum K1 with IC₅₀ values of 7.75 and 0.55?μg/mL, respectively. Compound 4 displayed antibacterial activity against Bacillus cereus with an MIC value of 6.25?μg/mL.     

Atalantums H-K from the peels of Atalantia monophylla and their cytotoxicity

Abstract

Four new benzoyltyramines, atalantums H-K (1–4) and seven known compounds were isolated from the peels of Atalantia monophylla. All compounds were tested for cytotoxicity against HeLa, HCT116 and MCF-7 cell lines, as well as normal cells (Vero cells). Compound 5 showed cytotoxicity against HeLa, HCT116 and MCF-7 cell lines with IC₅₀ values ranging from 16-25?μg/mL but was inactive against Vero cells. Compound 6 also showed interesting results as compound 5 with IC₅₀ values ranging from 15-18?μg/mL and an IC₅₀ value of 80.20?μg/mL against Vero cells. This means compounds 5 and 6 can be used as lead compounds for anticancer agents.     

Evaluation of the cytotoxicity on breast cancer cell of extracts and compounds isolated from Hyptis pectinata (L.) poit

Abstract

Hyptis pectinata is a herb popularly used in Brazil for the treatment of inflammations, pain, bacterial infections and cancer. In the present study, inflorescences (MPIn), leaves (MPL), branches (MPB), root (MPR) extracts and three compounds isolated from MPIn were assayed against breast tumor cell lines. The structures of the three compounds (pectinolide J, hyptolide and pectinolide E) were determined by means of spectroscopic analysis. Pectinolide J was isolated for the first time. The MPIn, MPL and MPR exhibited specific antiproliferative activity on tumor cell lines when compared to normal cell lines with IC₅₀ of 52.01?±?0.64, 45.91?±?0.02?μg/mL and 82.84?±?0.03?μg/mL, respectively. Although the isolated substances did not present good antiproliferative activity, when the three were associated, a greater biological effect was observed, suggesting a synergistic effect. Hyptolide (5.6?±?0.4?μg/mL) showed IC₅₀ sufficiently low to be considered as a drug prototype.     

Synthesis and fungicidal activity of novel 1,2,4-triazole derivatives containing a pyrimidine moiety

Abstract

A series of novel 1,2,4-triazole derivatives containing a pyrimidine moiety were synthesized and their fungicidal activities were evaluated. The preliminary biological test indicated that some of the target compounds exhibited moderate to good fungicidal activities against the tested plant pathogenic fungi compared with the commercial agent. Among them, compounds 9n and 9o exhibited excellent antifungal activity against Phompsis sp., with the half-maximal effective concentration (EC₅₀) values of 25.4 and 31.6?μg/mL, which were even better than the commercial agent of Pyrimethanil (32.1?μg/mL). Meanwhile, compound 9o showed better fungicidal activities against B. dothidea and B. cinerea with 40.1 and 55.1?μg/mL, respectively, in comparison with that of commercial Pyrimethanil (57.6 and 62.8?μg/mL).     

Two new compounds from cultures of the basidiomycete Antrodiella albocinnamomea

A new linear triterpene (1), and a new sesquiterpene (2), together with a known compound methyl indole-3-carboxylate (3) were isolated from the crude extract of Antrodiella albocinnamomea. The structures of the new compounds 1–2 were determined by comprehensive spectroscopic analysis. Compound 1 exhibited signi?cant inhibitory activities against protein tyrosine phosphatase 1B (PTP1B) with IC₅₀ value of 1.0 μg/mL.     

Synthesis,EGFR-TK inhibition and anticancer activity of new quinoxaline derivatives

Abstract

Ethyl 4-substituted-3-oxo-quinoxaline-2-carboxylates 3–5 were obtained via alkylation of ethyl 3-oxo-3,4-dihydroquinoxaline-2-carboxylate (1). Compound 1 was heterocyclized using hydrazines, ethylenediamine, and ethanolamine to give pyrazoloquinoxalines 6, 7, diazepinoquinoxaline 8, and oxazepinoquinoxaline 10. The quinoxaline-2-carboxamides 9, 11, 12 were prepared via condensation of compound 1 with different amines. Compound 1 was thiated using Lawesson’s reagent affording quinoxaline-3-thione 13, in fair yield. In addition, the reaction of 4-methyl-3-oxoquinoxaline 3 with some binucleophiles led to a series of new oxoquinoxaline derivatives 14–18. The molecular structure of compounds 1, 3, and 9 was confirmed by X-ray crystallography.

The anti-proliferative activity showed that among all the tested compounds, compounds 3, (IC₅₀ 2.51?±?3.0, 4.22?±?1.6 and 2.27?±?1.9?µM), 11 (IC₅₀ 1.32?±?2.61, 1.41?±?1.23 and 1.18?±?1.91?µM) and 17 (IC₅₀ 1.72?±?1.32, 1.85?±?0.94 and 1.92?±?4.83?µM) showed noteworthy anti-proliferative effects against the three cancer cell lines, HCT116, HePG2 and MCF7, respectively, compared to the reference drugs doxorubicin (IC₅₀ 1.41?±?0.58, 0.90?±?0.62 and 1.01?±?3.02?µM) and erlotinib (IC₅₀ 1.63?±?0.81, 1.57?±?0.62 and 1.49?±?0.54?µM). Compounds 3 (0.899?nM), 11 (0.508?nM) and 17 (0.807) showed strong EGFR inhibitory activity compared to Erlotinib (0.439?nM) and these results are in agreement with the docking study. These results suggest that compounds could probably be promising anticancer agents with EGFR inhibitory activity.     

Anti-inflammatory activity of saponins from roots of Impatiens parviflora DC.

Abstract

Two triterpene saponins (IPS-1, IPS-2) for the first time were isolated from the roots of Impatiens parviflora DC. (Balsaminaceae). Their anti-inflammatory activity was evaluated by means of two in vitro models: anti-hyaluronidase and anti-denaturation assays. Both saponins were shown to be potent hyaluronidase inhibitors that affect the enzyme in a dose-dependent manner. The anti-hyaluronidase effect of IPS-2 (IC₅₀?=?286.7?µg/mL) was higher than that of the reference drug: escin (IC₅₀?=?303.93?µg/mL). Both saponins protected bovine serum albumin from heat-induced denaturation in a dose-dependent manner. IPS-1 demonstrated higher anti-denaturation effect (IC₅₀?=?86.7?µg/ml) than IPS-2 (IC₅₀?=?109.76?µg/mL) or the standard drug: acetylsalicylic acid (IC₅₀?=?262.22?µg/mL). In conclusion, potent activity of IPS-1, IPS-2 in both in vitro assays shows that saponins from I. parviflora have anti-inflammatory activity. The obtained results allow to suggest that such compounds may be beneficial in inflammatory conditions, especially associated with excessive degradation of hyaluronic acid.     

Chemical constituents and cytotoxic activity from the wood-decaying fungus Xylaria sp. SWUF08-37

Abstract

A new cyclic pentapeptide, pentaminolarin (1), and a new cytochalasin, xylochalasin (2), along with thirteen known compounds (3–15) were isolated from the wood-decaying fungus Xylaria sp. SWUF08-37. The absolute configurations of 1 were determined by a combination of Marfey’s method and TDDFT ECD calculation and the absolute configurations of 2 were established by TDDFT ECD calculation. Compound 12 showed moderate cytotoxicity against HeLa (IC₅₀?=?19.60?µg/mL), HT29 (IC₅₀?=?17.31?µg/mL), HCT116 (IC₅₀?=?14.28?µg/mL), MCF-7 (IC₅₀?=?15.38?µg/mL), and Vero (IC₅₀?=?24.97?µg/mL) cell lines by MTT assay. Compounds 1 and 2 showed slight cytotoxicity against all tested cancer cell lines.     

Coumarin-pi,a new antioxidant coumarin derivative from Paxillus involutus

Abstract

Chemical investigation of Paxillus involutus lead to the isolation of a new coumarin derivative coumarin-pi (1), and three known compounds (2-4). The structure of the new compound was elucidated by interpretation of 1D and 2D NMR data. Compound 1 possesses a rare benzofuranylcoumarin skeleton. The isolated compounds were evaluated for antioxidant activities and coumarin-pi (1) exhibited significant activity with IC₅₀ value of 16.3?μg/mL.     

Rotenoid and isoflavone metabolites from an antioxidant seed extract of Dalbergia lanceolaria subsp. paniculata (roxb.) thoth

Abstract

A new rotenoid named 12-O-methylrotenolol along with five known rotenoid and isoflavone metabolites were isolated from the seeds of Dalbergia lanceolaria subsp. paniculata, collected from Egypt. The structures of these compounds were identified by physical and spectroscopic data measurements ([α]_D, UV, 1D- and 2D-NMR and MS). The methanol extract of the seeds exhibited strong antioxidant activity with IC₅₀ value 0.7?µg/µl against DPPH radical, in respect to quercetin as antioxidant reference (IC₅₀ 1.5?μM), while the tested compounds from this extract showed weak activities with IC₅₀ values ranged from 19.6 to 33.0?µM.