New compounds from the leaves of Cleistocalyx operculatus and their inhibitory activities on influenza A neuraminidases

Planta Medica ◽  
2016 ◽  
Vol 81 (S 01) ◽  
pp. S1-S381
Author(s):  
TKQ Ha ◽  
WK Oh
Keyword(s):  
Influenza A ◽  
Cleistocalyx Operculatus ◽  
Inhibitory Activities ◽  
New Compounds

scholarly journals New Diterpenoids and Isocoumarin Derivatives from the Mangrove-Derived Fungus Hypoxylon sp.

Marine Drugs ◽  
2021 ◽  
Vol 19 (7) ◽  
pp. 362
Author(s):  
Bolin Hou ◽  
Sushi Liu ◽  
Ruiyun Huo ◽  
Yueqian Li ◽  
Jinwei Ren ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Crude Extract ◽  
Mass Spectrometric ◽  
Spectrometric Analysis ◽  
Ic50 Values ◽  
Inhibitory Activities ◽  
The Absolute ◽  
Dpph Scavenging ◽  
New Compounds

Two new diterpenoids, hypoxyterpoids A (1) and B (2), and four new isocoumarin derivatives, hypoxymarins A–D (4–7), together, with seven known metabolites (3 and 8–13) were obtained from the crude extract of the mangrove-derived fungus Hypoxylon sp. The structures of the new compounds were elucidated on the basis of 1- and 2-dimensional (1D/2D) nuclear magnetic resonance (NMR) spectroscopic and mass spectrometric analysis. The absolute configurations of compounds 1, 2, 4, 5, and 7 were determined by comparison of experimental and calculated electronic circular dichroism (ECD) spectra, and the absolute configurations of C-4′ in 6 and C-9 in 7 were determined by [Rh2(OCOCF3)4]-induced ECD spectra. Compound 1 showed moderate α-glucosidase inhibitory activities with IC50 values of 741.5 ± 2.83 μM. Compounds 6 and 11 exhibited DPPH scavenging activities with IC50 values of 15.36 ± 0.24 and 3.69 ± 0.07 μM, respectively.

scholarly journals α-Amylase and α-Glucosidase Inhibitory Activities of Chemical Constituents from Wedelia chinensis (Osbeck.) Merr. Leaves

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Nguyen Phuong Thao ◽  
Pham Thanh Binh ◽  
Nguyen Thi Luyen ◽  
Ta Manh Hung ◽  
Nguyen Hai Dang ◽  
...  
Keyword(s):  
Spectroscopic Data ◽  
Chemical Constituents ◽  
2D Nmr ◽  
Inhibitory Effects ◽  
Meoh Extract ◽  
Inhibitory Activities ◽  
Isolated Compound ◽  
New Compounds ◽  
Modified Mosher’S Method

As part of an ongoing search for new natural products from medicinal plants to treat type 2 diabetes, two new compounds, a megastigmane sesquiterpenoid sulfonic acid (1) and a new cyclohexylethanoid derivative (2), and seven related known compounds (3–9) were isolated from the leaves of Wedelia chinensis (Osbeck.) Merr. The structures of the compounds were conducted via interpretation of their spectroscopic data (1D and 2D NMR, IR, and MS), and the absolute configurations of compound 1 were determined by the modified Mosher’s method. The MeOH extract of W. chinensis was found to inhibit α-amylase and α-glucosidase inhibitory activities as well as by the compounds isolated from this extract. Furthermore, compound 7 showed the strongest effect with IC50 values of 112.8 ± 15.1 μg/mL (against α-amylase) and 785.9 ± 12.7 μg/mL (against α-glucosidase). Compounds 1, 8, and 9 showed moderate α-amylase and α-glucosidase inhibitory effects. Other compounds showed weak or did not show any effect on both enzymes. The results suggested that the antidiabetic properties from the leaves of W. chinensis are not simply a result of each isolated compound but are due to other components such as the accessibility of polyphenolic groups to α-amylase and α-glucosidase activities.

scholarly journals Synthesis and anti-acetylcholinesterase activities of novel glycosyl coumarylthiazole derivatives

2020 ◽  
pp. 174751982094835
Author(s):  
You-Xian Wang ◽  
Shu-Hao Liu ◽  
Zhong-Bai Shao ◽  
Lian-Gong Cao ◽  
Kai-Jun Jiang ◽  
...  
Keyword(s):  
Electrospray Ionization ◽  
New Products ◽  
Reaction Conditions ◽  
Inhibitory Rate ◽  
Inhibitory Activities ◽  
Ellman’S Method ◽  
New Compounds ◽  
C Nmr

Eleven glycosyl coumarylthiazole derivatives are synthesized by cyclization and condensation of glycosyl thiourea with 3-bromoacetyl coumarins in ethanol. The reaction conditions are optimized and good yields of products (80%–95%) are obtained. The structures of all new products were confirmed by IR, 1H and 13C NMR, and by HRMS (electrospray ionization). The in vitro acetylcholinesterase (AChE) inhibitory activities of these new compounds are tested by Ellman’s method. Among them, N-(2-acetamido-3,4,6-tri- O-acetyl-2-deoxy-β-D-glucopyranosyl)-4-(6-nitrocoumarinyl)-1,3-thiazole-2-amine showed the best activity with an in vitro AChE inhibitory rate of 58% and an IC50 value of 12 ± 0.38 μg/mL.

scholarly journals Dereplication by High-Performance Liquid Chromatography (HPLC) with Quadrupole-Time-of-Flight Mass Spectroscopy (qTOF-MS) and Antiviral Activities of Phlorotannins from Ecklonia cava

Marine Drugs ◽  
2019 ◽  
Vol 17 (3) ◽  
pp. 149 ◽  
Author(s):  
Hyo Cho ◽  
Thi Doan ◽  
Thi Ha ◽  
Hyun Kim ◽  
Ba Lee ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Influenza A ◽  
High Performance ◽  
High Resolution Mass Spectrometry ◽  
Ecklonia Cava ◽  
Relative Mass ◽  
Edible Seaweed ◽  
Diarrhea Virus ◽  
Antiviral Activities ◽  
New Compounds

Ecklonia cava is edible seaweed that is found in Asian countries, such as Japan and Korea; and, its major components include fucoidan and phlorotannins. Phlorotannins that are isolated from E. cava are well-known to have an antioxidant effect and strong antiviral activity against porcine epidemic diarrhea virus (PEDV), which has a high mortality rate in piglets. In this study, the bioactive components were determined based on two different approaches: (i) bio-guided isolation using the antiviral activity against the H1N1 viral strain, which is a representative influenza virus that originates from swine and (ii) high-resolution mass spectrometry-based dereplication, including relative mass defects (RMDs) and HPLC-qTOFMS fragmentation analysis. The EC70 fraction showed the strongest antiviral activity and contained thirteen phlorotannins, which were predicted by dereplication. Ten compounds were directly isolated from E. cava extract and then identified. Moreover, the dereplication method allowed for the discovery of two new phlorotannins. The structures of these two isolated compounds were elucidated using NMR techniques and HPLC-qTOFMS fragmentation analysis. In addition, molecular modelling was applied to determine the absolute configurations of the two new compounds. The antiviral activities of seven major phlorotannins in active fraction were evaluated against two influenza A viral strains (H1N1 and H9N2). Six of the compounds showed moderate to strong effects on both of the viruses and phlorofucofuroeckol A (12), which showed an EC50 value of 13.48 ± 1.93 μM, is a potential active antiviral component of E. cava.

Isoprenylated Phenolic Compounds from Morus macroura as Potent Tyrosinase Inhibitors

Planta Medica ◽  
2017 ◽  
Vol 84 (05) ◽  
pp. 336-343 ◽  
Author(s):  
Yifan Wang ◽  
Liangjin Xu ◽  
Wen Gao ◽  
Lixin Niu ◽  
Chunyue Huang ◽  
...  
Keyword(s):  
Kojic Acid ◽  
Positive Control ◽  
Diels Alder ◽  
Extensive Analysis ◽  
Ic50 Value ◽  
Ic50 Values ◽  
Tyrosinase Inhibitors ◽  
Inhibitory Activities ◽  
New Compounds

AbstractThree new Diels-Alder adducts, macrourins E – G (1–3), one new 2-arylbenzofuran, macrourin H (4), and eight known Diels-Alder adducts (5–12) were isolated from Morus macroura. Their structures were elucidated through extensive analysis of spectroscopic data. The 1H NMR and ECD trends in the determination of the configurations of these Diels-Alder adducts were summarized. The tyrosinase inhibitory activities of all compounds isolated were evaluated, and the new compounds (1–4) as well as the eight known compounds (5–12) were found to be potent with IC50 values ranging from 0.39 to 4.54 µM. Among them, 1 showed the best tyrosinase inhibitory activity with an IC50 value of 0.39 µM, approximately 50 times stronger than the positive control, kojic acid.

scholarly journals α-Glucosidic Hydroquinone Derivatives from Viburnum Erosum

2021 ◽  
Author(s):  
Jinyoung Park ◽  
Jiho Lee ◽  
Hyeon S. Jang ◽  
Birang Jeong ◽  
Seong Y. Choi ◽  
...  
Keyword(s):  
Positive Control ◽  
Spectroscopic Methods ◽  
Spectroscopic Analyses ◽  
Potent Inhibition ◽  
Inhibitory Activities ◽  
Tyrosinase Enzyme ◽  
New Compounds

<p>Six new compounds<b> </b>(<b>1−6</b>) were isolated from the leaves of <i>Viburnum erosum</i> along with four known compounds <b>7−10</b>. The structures were determined by NMR and MS spectroscopic analyses, and their absolute configurations were established by chemical and spectroscopic methods. Compounds <b>1–6</b> were <i>α</i>-glucosidic hydroquinone derivatives with different linear monoterpenoid structures. Compounds <b>1−10 </b>were also evaluated for their tyrosinase inhibitory activities, and <b>10</b> showed potent inhibition of tyrosinase enzyme with IC<sub>50</sub> of 37.9 <i>μ</i>M compared to 47.6 <i>μ</i>M of the positive control (<i>β</i>-arbutin).</p>

Anthraquinone analogues with inhibitory activities against influenza a virus from Polygonatum odoratum

2020 ◽  
pp. 1-7
Author(s):  
Xu Pang ◽  
Jian-Yuan Zhao ◽  
Ning Liu ◽  
Ming-Hua Chen ◽  
Wei Zheng ◽  
...  
Keyword(s):  
Influenza A Virus ◽  
Influenza A ◽  
Inhibitory Activities

scholarly journals New Fluorene Derivatives from Dendrobium gibsonii and Their α-Glucosidase Inhibitory Activity

Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 4931
Author(s):  
May Thazin Thant ◽  
Nutputsorn Chatsumpun ◽  
Wanwimon Mekboonsonglarp ◽  
Boonchoo Sritularak ◽  
Kittisak Likhitwitayawuid
Keyword(s):  
Kinetic Study ◽  
Inhibitory Activity ◽  
Spectroscopic Data ◽  
Enzyme Kinetic ◽  
Whole Plant ◽  
Noncompetitive Inhibitor ◽  
Inhibitory Activities ◽  
New Compounds ◽  
Enzyme Kinetic Study

Two new compounds, dihydrodengibsinin (1) and dendrogibsol (2), were isolated from the whole plant of Dendrobium gibsonii, together with seven known compounds (3–9). The structures of the new compounds were elucidated by their spectroscopic data. All these isolates were evaluated for their α-glucosidase inhibitory activities. Dendrogibsol (2) and lusianthridin (7) showed strong α-glucosidase inhibitory activity when compared with acarbose. An enzyme kinetic study revealed that dendrogibsol (2) is a noncompetitive inhibitor of α-glucosidase.

Design and Discovery of Novel Quinoxaline Derivatives as Dual DNA Intercalators and Topoisomerase II Inhibitors

2018 ◽  
Vol 18 (2) ◽  
pp. 195-209 ◽  
Author(s):  
Ibrahim H. Eissa ◽  
Abeer M. El-Naggar ◽  
Nour E.A. Abd El-Sattar ◽  
Ahmed S. A. Youssef
Keyword(s):  
Dna Binding ◽  
Cell Lines ◽  
Topoisomerase Ii ◽  
Docking Studies ◽  
Binding Affinities ◽  
Quinoxaline Derivatives ◽  
Inhibitory Activities ◽  
Cytotoxicity Activities ◽  
New Compounds

Backgroun/Methods: In attempt to develop new potent anti-tumor agents, a series of quinoxaline derivatives was designed and synthesized. The novel compounds were tested in vitro for their anti-proliferative activities against HePG-2, MCF-7 and HCT-116 cell lines. Additionally, DNA binding affinities as well as DNA-top II inhibitory activities of the synthesized compounds were investigated as potential mechanism for anticancer activity. Compounds 13, 15, 16 and 19 exhibited good cytotoxicity activities against the three cell lines (IC50 ranging from 7.6 to 32.4 µM) comparable to that of doxorubicin (IC50 = 9.8 µM). Results: Interestingly, the results of DNA binding and DNA-top II inhibition assays were in agreement with those of the cytotoxicity tests, where the most potent anticancer compounds showed good DNA binding affinities (IC50 ranging from 25.1 to 32.4 µM) and DNA-top II inhibitory activities (IC50 ranging from 6.4 to 15.3 µM) comparable to those of doxorubicin (IC50 = 28.1 and 3.8 μM, respectively). Furthermore, molecular docking studies were carried out for the new compounds in order to investigate their binding pattern with the prospective target, DNA-top II complex (PDB-code: 3qx3).

scholarly journals Inhibition of SARS-CoV 3C-like Protease Activity by Theaflavin-3,3'-digallate (TF3)

2005 ◽  
Vol 2 (2) ◽  
pp. 209-215 ◽  
Author(s):  
Chia-Nan Chen ◽  
Coney P. C. Lin ◽  
Kuo-Kuei Huang ◽  
Wei-Cheng Chen ◽  
Hsin-Pang Hsieh ◽  
...  
Keyword(s):  
Severe Acute Respiratory Syndrome ◽  
Inhibitory Activity ◽  
Black Tea ◽  
Host Cells ◽  
Epicatechin Gallate ◽  
Natural Polyphenols ◽  
Different Types ◽  
Natural Product Library ◽  
Inhibitory Activities ◽  
New Compounds

SARS-CoV is the causative agent of severe acute respiratory syndrome (SARS). The virally encoded 3C-like protease (3CLPro) has been presumed critical for the viral replication of SARS-CoV in infected host cells. In this study, we screened a natural product library consisting of 720 compounds for inhibitory activity against 3CLPro. Two compounds in the library were found to be inhibitive: tannic acid (IC50 = 3 µM) and 3-isotheaflavin-3-gallate (TF2B) (IC50 = 7 µM). These two compounds belong to a group of natural polyphenols found in tea. We further investigated the 3CLPro-inhibitory activity of extracts from several different types of teas, including green tea, oolong tea, Puer tea and black tea. Our results indicated that extracts from Puer and black tea were more potent than that from green or oolong teas in their inhibitory activities against 3CLPro. Several other known compositions in teas were also evaluated for their activities in inhibiting 3CLPro. We found that caffeine, (—)-epigallocatechin gallte (EGCg), epicatechin (EC), theophylline (TP), catechin (C), epicatechin gallate (ECg) and epigallocatechin (EGC) did not inhibit 3CLPro activity. Only theaflavin-3,3′-digallate (TF3) was found to be a 3CLPro inhibitor. This study has resulted in the identification of new compounds that are effective 3CLPro inhibitors.

Sign in / Sign up

Export Citation Format

Share Document