Antioxidant and α-Glucosidase Inhibitory Compounds of Centella Asiatica

Centella asiatica, as known as Pegagan was previously reported to have anti-hyperglycemic effects in animal diabetic model rats. However, its α-glucosidase activity in vitro assay not yet reported. Our goal in this study is to isolate and identify active compounds as α-glucosidase inhibitor and antioxidant from aqueous ethanol 70% (v/v) extract of C. asiatica. The extract was partitioned by n-hexane, EtOAc, and n-butanol sequentially. Among the fractions tested, EtOAc fraction was showed the highest antioxidant and α-glucosidase inhibitory activities with an IC₅₀ values of 45.42 and 73.17 μg/mL, respectively. The antioxidant activity was conducted by determination of DPPH radical scavenging activity, whereas α-glucosidase inhibitory activity was determined against yeast α-glucosidase. Furthermore, isolation of the ethyl acetate extract yielded two active compounds, which were identified as kaempferol (1) and quercetin (2). Both of the compounds showed good yeast α-glucosidase inhibitory activity with IC₅₀ values of 16.50 and 21.61 μg/mL, respectively. In addition those compounds also could scavenge DPPH radical activity with IC₅₀ values of 9.64 and 11.97 μg/mL, respectively. Due to its ability in reducing α-glucosidase activity and scavenging free radical activity, the C. asiatica appears to be a potential as a good resource for future development of antioxidant and antidiabetic drug.     

Synthesis and Bioactivity of Arecoline Derivatives Containing Amino-s-triazole Coupled Oxadiazole

Recently, the increasing demand for effective treatment of cardiovascular diseases (CD), such as hypertension, heart failure, hypercholesterolemia, atherosclerosis, is becoming urgent task. The researches in therapeutics for CD focus on the modification o…     

Synthesis and α-Glucosidase Inhibitory Activity of Ursolic Acid,Lupeol, and Betulinic Acid Derivatives

Chemistry of Natural Compounds - Seven synthetic derivatives of ursolic acid, lupeol, and betulinic acid (1a–1b, 2a–2b, and 3a–3c) were synthesized to study their...     

Synthesis,In Vitro α-Amylase Activity,and Molecular Docking Study of New Benzimidazole Derivatives

Russian Journal of Organic Chemistry - New benzimidazole derivatives were synthesized by reacting substituted phenacyl bromides with 1H-benzimidazole-2-thiols. The synthesized compounds were...     

Synthesis, Structure and Biological Activities of Novel Triazole Compounds Containing N,N-Dialkyldithiocarbamate Moiety

Introduction As an important type of fungicides, triazole compounds are highly efficient, low poisonous and inward absorbent.1-3 At present, the studies on triazole derivatives are mainly concentrated on compounds with triazole as the only active group. The report of triazole compounds that contain both triazole group and other active group in a single molecule has rarely been found. Dialkyl-substituted dithiocarbamate salts have also shown interesting biological effects.4 N,N-Dialkyldithio-…     

Design,Synthesis and Antifungal Activity of Novel Triazole Derivatives

Twenty-one 1-(1H-1,2,4-triazolyl)-2-(2,4-diflurophenyl)-3-(4-substituted-1-piperazinyl)-2-propanol derivatives were designed and synthesized,on the basis of the active site of lanosterol 14α-demethylase.In vitro antifungal activities showed that some of the target compounds had higher antifungal activity and broader antifungal spectrum than fluconazole.     

Synthesis and Inhibitory Effect of Some Indole-Pyrimidine Based Hybrid Heterocycles on α-Glucosidase and α-Amylase as Potential Hypoglycemic Agents

The Michael addition reaction of barbituric acid with chalcones incorporating the indole scaffold was achieved by using a highly efficient bimetallic Iron–palladium catalyst in the presence of acetylacetone (acac). This catalytic approach produced the desired products in a simple operation and low catalyst loading with acceptable yield of the new hybrids. All tested compounds were subjected for biological activity on α-glucosidase and α-amylase. The results revealed that all synthesized compounds exhibited very good activity against both enzymes when compared to positive control (acarbose). Moreover, compound 5o showed the best activity whereas its IC₅₀ (μM) are 13.02+0.01 and 21.71+0.82 for α-glucosidase and α-amylase respectively. Both compounds 5o and 5l exhibited high similarity in binding mode and pose with amylase protein (4UAC). The obtained data may be used for developing potential hypoglycemic agents.     

Synthesis, Structure and Biological Activities of Novel Triazole Compounds Containing 4,6-Dimethyl-pyrimidin-2-ylthio Group

Introduction As an important type of fungicides, triazole com-pounds are highly efficient, low poisonous and inward absorbent.1-3 At present, the studies on triazole deriva-tives are mainly concentrated on compounds with tria-zole as the only active group. The report on triazole compounds that contain both triazole group and other active group in a single molecule has rarely been found. Some pyrimidines have been used as highly efficient and lowly poisonous fungicides4 in controling powdery mi…     

Solvent-and Catalyst-free Synthesis and Antifungal Activities of α-Aminophosphonate Containing Cyclopropane Moiety

Nine new α-aminophosphonate derivatives containing cyclopropane moiety have been synthesized via conventional and microwave irradiation methods under solvent-and catalyst-free condition. The structures of the title compounds have been confirmed by 1H NMR, 31P NMR, FTIR, EI-MS and FTICR-MS. Their antifungal activities were evaluated in vivo and some of the compounds were found to exhibit excellent antifungal activities against Corynespora cassiicola, Pseudomonas syringae pv. Lachrymans, Pseudoperonospora cubensis and Sclerotinia sclerotiorum.     

Synthesis and Herbicidal Activity of α-Hydroxy Phosphonate Derivatives Containing Pyrimidine Moiety

A series of α‐hydroxy phosphonate derivatives containing pyrimidine moiety were designed and synthesized. Their structures were characterized by IR, ¹H NMR, MS and elemental analysis. The results of preliminary herbicidal activities (in vitro) showed that some of the title compounds 2 exhibited moderate herbicidal activities against dicotyledonous weeds (Brassica campestris L), and most of compounds 2 showed better activity against dicotyledonous weeds than monocotyledonous weeds (Echinochloa crus‐galli). Further bioassays (in vivo) indicated that some of the title compounds 2 possessed good and selective herbicidal activity against amaranth pigweed (A. retroflexus) in both pre‐ and post‐emergence treatments at the dose of 1.5 kg/ha. For exmple, compounds 2a , 2b and 2e exhibited 100% inhibition against A. retroflexus in pre‐emergence treatment, and 91.7%, 98.8% and 99.5% inhibition in post‐emergence treatment at the dose of 1.5 kg/ha, respectively.     

Synthesis and Herbicidal Activity of α-Amino Phosphonate Derivatives Containing Thiazole and Pyrazole Moieties

A series of novel α-amino phosphonate derivatives containing the thiazole and pyrazole moieties 3 were synthesized by the Mannich-type reaction of substituted pyrazole-aldehyde 1, 2-amino-5-ethoxycarbonyl-4-methyl-thiazole 2, and dialkyl phosphites or triphenyl phosphite in the presence of a Lewis acid such as magnesium perchlorate as the catalyst under solvent-free conditions. Their structures were clearly confirmed by spectroscopy data (IR, ¹H NMR, ³¹P NMR, MS) and elemental analysis. The results of a preliminary bioassay (in vitro) indicated that some of the title compounds 3 possessed moderate herbicidal activities against dicotyledonous plants (Brassica campestris L) or monocotyledonous plants (Echinochloa crus-galli) at the concerntration of 100 mg/L.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Synthesis,Characterization, and Biological Screening of Some Novel Thiazolidin-4-One and α-Aminophosphonate Derivatives

Abstract

Synthesis of some new functionalized thiazolidin-4-ones and α-amino phosphonate derivatives has been reported. The imines were synthesized from the reaction of various substituted anilines with 1-phenyl-3-(pyridine-4-yl)-1H-pyrazole-4-carbaldehyde in ethanol at reflux condition. The corresponding thiazolidin-4-ones and α-aminophosphonates were prepared by reaction of imines with mercaptoacetic acid and triethyl phosphite, respectively. The structures of the newly synthesized compounds were confirmed by IR, ¹H NMR, and mass spectral data and were evaluated for their antimicrobial activities.

GRAPHICAL ABSTRACT      

Studies on Synthesis and Biological Activities of Novel Triazole Compounds Containing Pyrimidine or N, N－Dialkyldithiocarbamate Ring

Twelve of the title compounds were synthesized. Their structures were identified by means of IR, EA, IH NMR and MS. The IR spectra clearly show that the absorptions in the regions of 1716—1666 cm^-1 and 1505—1499 cm^-1 are the characteristic absorption bands for vc=O and vc=N. In the IH NMR spectra of target compounds(10a—10g), three protons of a = CH—CH2— group present three sets of quartet peaks of the protons. The preliminary bioassays showed that the synthesized compounds exhibited some activities of fungicides and plant growth regulators.     

Synthesis of Some New 1,3,2-Oxazaphosphinine, 1,3,2-Diazaphosphinine,Acyclic, and/or Cyclic α-Aminophosphonate Derivatives Containing the Chromone Moiety

The synthesis of some new 1,3,2-oxazaphosphinine 18, 1,3,2-diazaphosphinine 19, acyclic, and cyclic α-aminophosphonate derivatives 3–17 containing the chromone moiety have been achieved via reaction of 3-(phenyliminomethyl)chromone (1), 3-(phenylaminomethylene)-2-hydroxychromanone (4), and/or 3-(phenylamino-methylene)-2-(phenylamino)chromanone (5) with diethyl phosphite, tris(2-chloroethyl)phosphite, and phenylphosphonic dichloride. Structures of the products were verified on the basis of their elemental analyses, IR, ¹H, and ³¹P NMR spectral data.     

Synthesis of New Purine Derivatives Containing α- and ω-Amino Acid Fragments

Russian Journal of Organic Chemistry - New conjugates of purine and 2-aminopurine with several α- and ω-amino acids have been synthesized following two approaches based on the...     

Synthesis,Characterization, and Antimicrobial Evaluation of Quinoline-Oxadiazole–Based Azetidinone Derivatives

A series of 3-chloro-1-(aryl)-4-(2-(2-chloroquinolin-3-yl)-5-(pyridin-4-yl)-1,3,4-oxadiazol-3(2H)-yl)-4-ethyl-azetidin-2-ones (5a–l) have been synthesized and characterized by IR, ¹H NMR, and¹³C NMR. Synthesized compounds were screened for their antimicrobial activity against different strains of bacteria (E. coli, P. aeruginosa, S. aureus, S. pyogenes, C. albicans, A. niger, and A. clavatus). On the basis of statistical analysis, it has been observed that compounds had significant correlations.     

Inhibitory Activities on α-Glucosidase and Composition Analysis of Different Fractions of Ethanol Extracts from Actinidia chinensis Radix

Tlie inhibitory actions of ethyl acetate,n-butanol and water fractions from Actinidia chinensis Radix (A. chinensis Radix) ethanol extracts on glucosidase were investigated. We found that the inhibitory activity of different ethanol extract fractions on α-glucosidase is concentration-dependent. At the same concentration, the ethyl acetate and n-butaiiol fractions showed higher inliibitory activities on gglucosidase in comparison witli acarbose. We then determined the chemical constituents of tlie ethyl acetate and n-butanol fractions through ultra performance liquid cliromatography-triple-time of flight/mass spectrometry(UPLC-Triple-TOF/MS). Based on the mass spectrometry analysis and the databases Scitinder and Reaxys, 21 compoiinds(A1-A21) were identified from the ethyl acetate fraction. In addition, 11 of those compounds(A2, A3, A5, A6, A8, A10, A11, A13, A15, A19, A20) were identified for the first time from A. chinensis Radix. We also identified 14 compounds(A22-A32 and A4-A6) from tlie w-butanol fraction and compound A29 is a new natural product. From the n-butanol fraction, 7 additional compounds (A22, A25, A27, A28, A30-A32) were identified from A. chinensis Radix for the first time.     

Synthesis of Pyridyl Polyheterocyclic Oxime-ether Schiff Bases Containing s-Triazole and Oxadiazole Subunits

4-Amino-3-substituted-5-mercapto-s-triazole derivatives are an important intermediate for the synthesis of biologically active heterocycles 1-4 including antibacterial, antifungal, anticancer agents. Before, the researches mainly focused on its fused hete…     

Synthesis and Herbicidal Activity of Novel Pyrimidinyl Derivatives Containing an α-Amino Phosphonate Moiety

In order to find novel pyrimidinyl carboxylic acid analogs with high activity and low toxicity, a series of novel pyrimidinyl derivatives containing an α-amino phosphonate moiety 5 was synthesized by the condensation of 4-(4,6-dimethoxypyrimidin-2-yloxy)phenoxyacetic 3a or propionic acids 3b with dialkyl α-amino substitutedbenzyl phosphonates 4. Their structures were characterized by spectroscopic data (IR, ¹H NMR, ³¹P NMR, MS) and elemental analyses. The results of preliminary herbicidal activities (in vitro) showed that most of these compounds exhibited higher herbicidal activities against dicotyledonous weeds (Brassica campestris L) than monocotyledonous weeds (Echinochloa crus-galli). Further bioassays (in vivo) indicated that some of compounds 5 possessed selective herbicidal activity against amaranth pigweed (A. retroflexus) in post-emergence treatment.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.