scholarly journals Flavonoids from the Genus Euphorbia: Isolation, Structure, Pharmacological Activities and Structure–Activity Relationships

2021 ◽  
Vol 14 (5) ◽  
pp. 428
Author(s):  
Douglas Kemboi Magozwi ◽  
Mmabatho Dinala ◽  
Nthabiseng Mokwana ◽  
Xavier Siwe-Noundou ◽  
Rui W. M. Krause ◽  
...  
Keyword(s):  
Therapeutic Potential ◽  
Antioxidant Properties ◽  
Structure Activity Relationship ◽  
Biological Properties ◽  
Therapeutic Agents ◽  
Skeletal Structure ◽  
Activity Relationship ◽  
Hydroxyl Groups ◽  
Structure Activity ◽  
Review Reports

Plants of the genus Euphorbia are widely distributed across temperate, tropical and subtropical regions of South America, Asia and Africa with established Ayurvedic, Chinese and Malay ethnomedical records. The present review reports the isolation, occurrence, phytochemistry, biological properties, therapeutic potential and structure–activity relationship of Euphorbia flavonoids for the period covering 2000–2020, while identifying potential areas for future studies aimed at development of new therapeutic agents from these plants. The findings suggest that the extracts and isolated flavonoids possess anticancer, antiproliferative, antimalarial, antibacterial, anti-venom, anti-inflammatory, anti-hepatitis and antioxidant properties and have different mechanisms of action against cancer cells. Of the investigated species, over 80 different types of flavonoids have been isolated to date. Most of the isolated flavonoids were flavonols and comprised simple O-substitution patterns, C-methylation and prenylation. Others had a glycoside, glycosidic linkages and a carbohydrate attached at either C-3 or C-7, and were designated as d-glucose, l-rhamnose or glucorhamnose. The structure–activity relationship studies showed that methylation of the hydroxyl groups on C-3 or C-7 reduces the activities while glycosylation loses the activity and that the parent skeletal structure is essential in retaining the activity. These constituents can therefore offer potential alternative scaffolds towards development of new Euphorbia-based therapeutic agents.

scholarly journals Inhibition of Lipoxygenase and Peroxidase Reaction by Some Flavonols and Flavones: The Structure-Activity Relationship

2017 ◽  
Vol 12 (11) ◽  
pp. 1934578X1701201
Author(s):  
Zbigniew Sroka ◽  
Alina Sowa ◽  
Andrzej Dryś
Keyword(s):  
Correlation Coefficient ◽  
Antioxidant Properties ◽  
Structure Activity Relationship ◽  
Methoxyl Group ◽  
Activity Relationship ◽  
Hydroxyl Group ◽  
Hydroxyl Groups ◽  
Peroxidase Reaction ◽  
Structure Activity ◽  
Reducing Properties

Some flavonoids were investigated for their effects on lipoxygenase and peroxidase. The strongest inhibitor of lipoxygenase was kaempferol with one hydroxyl group situated at the 4’ position in the B ring, with activity of 21.2±2.03 calculated per μmole of compound. The weakest inhibition was observed for diosmetin with a hydroxyl group at the 3′ position and a methoxyl group at 4′ in the B ring, with activity of 1.17±0.77 per μmole. Peroxidase was most strongly inhibited by quercetin (22.7±0.05) with two hydroxyl groups in the B ring at 3′ and 4′. The weakest inhibitor of peroxidase was genkwanin (0±0.16) with one hydroxyl group at position 4′ in the B ring and methoxyl at position 7 in the A ring. The correlation coefficient between reduction of Fe3+ by flavonoids and inhibition of lipoxygenase by these compounds was 0.72 and the reduction of Fe3+ and inhibition of peroxidase was 0.24. The results show that inhibition of peroxidase is weakly associated with reducing properties of phenols and inhibition of lipoxygenase may be associated with antioxidant properties of flavonoids.

Recent Progress in Methylation of (Hetero)Arenes by Cross-Coupling or C–H Activation

Synlett ◽  
2018 ◽  
Vol 29 (04) ◽  
pp. 375-382 ◽  
Author(s):  
Yahu Liu ◽  
Xuebin Liao ◽  
Lu Hu
Keyword(s):  
Recent Progress ◽  
Cross Coupling ◽  
Structure Activity Relationship ◽  
Biological Properties ◽  
Aryl Halides ◽  
Lead Optimization ◽  
Activity Relationship ◽  
Research Groups ◽  
Structure Activity ◽  
Methyl Effect

Owing to the ‘magic methyl effect’ on a compound’s physical and biological properties, methylation is a strategy frequently used by medicinal chemists in structure–activity relationship studies or in lead optimization. This article highlights the most recent reported methods for the direct methylation of (hetero)arenes, which mainly involve either C–H functionalization or cross-coupling of methylating reagents with (hetero)aryl halides. Methylation of C–H bonds of (hetero)-arenes, which is atom economical, has been explored by several research groups in recent years. Given the unmatchable availability of (hetero)aryl halides, we believe that Ni-catalyzed methylation using iodomethane or deuterated iodomethane as the methyl source is one of the most convenient methods.

scholarly journals Structure–Activity Relationships (SARs) of α-Ketothioamides as Inhibitors of Phosphoglycerate Dehydrogenase (PHGDH)

2020 ◽  
Vol 13 (2) ◽  
pp. 20
Author(s):  
Quentin Spillier ◽  
Séverine Ravez ◽  
Judith Unterlass ◽  
Cyril Corbet ◽  
Charline Degavre ◽  
...  
Keyword(s):  
Cancer Progression ◽  
Structure Activity Relationship ◽  
Therapeutic Agents ◽  
Activity Relationship ◽  
Cancer Treatments ◽  
Promising Strategy ◽  
Structure Activity ◽  
Phosphoglycerate Dehydrogenase ◽  
Relationship Study

For many years now, targeting deregulation within cancer cells’ metabolism has appeared as a promising strategy for the development of more specific and efficient cancer treatments. Recently, numerous reports highlighted the crucial role of the serine synthetic pathway, and particularly of the phosphoglycerate dehydrogenase (PHGDH), the first enzyme of the pathway, to sustain cancer progression. Yet, because of very weak potencies usually in cell-based settings, the inhibitors reported so far failed to lay ground on the potential of this approach. In this paper, we report a structure–activity relationship study of a series of α-ketothioamides that we have recently identified. Interestingly, this study led to a deeper understanding of the structure–activity relationship (SAR) in this series and to the identification of new PHGDH inhibitors. The activity of the more potent compounds was confirmed by cellular thermal shift assays and in cell-based experiments. We hope that this research will eventually provide a new entry point, based on this promising chemical scaffold, for the development of therapeutic agents targeting PHGDH.

Antioxidant properties of phenolic Schiff bases: structure–activity relationship and mechanism of action

2013 ◽  
Vol 27 (11) ◽  
pp. 951-964 ◽  
Author(s):  
El Hassane Anouar ◽  
Salwa Raweh ◽  
Imene Bayach ◽  
Muhammad Taha ◽  
Mohd Syukri Baharudin ◽  
...  
Keyword(s):  
Schiff Bases ◽  
Mechanism Of Action ◽  
Antioxidant Properties ◽  
Structure Activity Relationship ◽  
Activity Relationship ◽  
Structure Activity

scholarly journals Recent progress in pyrolyzed carbon materials as electrocatalysts for the oxygen reduction reaction

2020 ◽  
Vol 7 (1) ◽  
pp. 28-36 ◽  
Author(s):  
Chen Ouyang ◽  
Xun Wang
Keyword(s):  
Oxygen Reduction Reaction ◽  
Oxygen Reduction ◽  
Recent Progress ◽  
Carbon Materials ◽  
Pyrolytic Carbon ◽  
Structure Activity Relationship ◽  
Reduction Reaction ◽  
Activity Relationship ◽  
Structure Activity ◽  
Review Reports

This review reports some recent advances in pyrolytic carbon as an ORR catalyst and explores its structure–activity relationship.

scholarly journals Structure–activity relationship of surface hydroxyl groups during NO2 adsorption and transformation on TiO2 nanoparticles

2017 ◽  
Vol 4 (12) ◽  
pp. 2388-2394 ◽  
Author(s):  
Chang Liu ◽  
Qingxin Ma ◽  
Hong He ◽  
Guangzhi He ◽  
Jinzhu Ma ◽  
...  
Keyword(s):  
Tio2 Nanoparticles ◽  
Structure Activity Relationship ◽  
Activity Relationship ◽  
Hydroxyl Groups ◽  
Surface Hydroxyl ◽  
Surface Hydroxyl Groups ◽  
Structure Activity ◽  
No2 Adsorption ◽  
Relationship Of ◽  
Structure And Activity

The structure and activity of surface hydroxyl groups determined the performance of TiO2 during NO2 reaction.

Cytotoxic and antioxidant effects of methoxylated stilbene analogues on HepG2 hepatoma and Chang liver cells: Implications for structure activity relationship

2010 ◽  
Vol 30 (2) ◽  
pp. 138-144 ◽  
Author(s):  
AH Hasiah ◽  
AR Ghazali ◽  
JFF Weber ◽  
S. Velu ◽  
NF Thomas ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Activities ◽  
Structure Activity Relationship ◽  
Liver Cells ◽  
Activity Relationship ◽  
Hydroxyl Groups ◽  
Structure Activity ◽  
Total Antioxidant ◽  
Stilbene Analogues ◽  
Chang Liver

Stilbenes possess a variety of biological activities including chemopreventive activity. This study was conducted to evaluate the structural activity relationships of six methoxylated stilbene analogues with respect to their cytotoxic effects and antioxidant activities on HepG2 hepatoma and Chang liver cells. The cytotoxic and total antioxidant activities of six stilbene analogues were determined by MTT and Ferric Reducing Antioxidant Power (FRAP) assays, respectively. We found that the cis-methoxylated stilbene: (Z)-3,4,4'-trimethoxystilbene was the most potent and selective antiproliferative agent (IC50 89 µM) in HepG2 cells. For the total antioxidant activity, compounds possessing hydroxyl groups at the 4' position namely (E)-3-methoxy-4'-hydroxystilbene, (E)-3,5-dimethoxy-4'-hydroxystilbene (pterostilbene), (E)-4-methoxy-4'-hydroxystilbene showed the highest antioxidant activity. Structure activity relationship studies of these compounds demonstrated that the cytotoxic effect and antioxidant activities of the tested compounds in this study were structurally dependent.

Structure–activity relationship of Au/ZrO2 catalyst on formation of hydroxyl groups and its influence on CO oxidation

2013 ◽  
Vol 1 (19) ◽  
pp. 6051 ◽  
Author(s):  
Christopher J. Karwacki ◽  
P. Ganesh ◽  
Paul R. C. Kent ◽  
Wesley O. Gordon ◽  
Gregory W. Peterson ◽  
...  
Keyword(s):  
Co Oxidation ◽  
Structure Activity Relationship ◽  
Activity Relationship ◽  
Hydroxyl Groups ◽  
Structure Activity ◽  
Zro2 Catalyst ◽  
Relationship Of
Sign in / Sign up

Export Citation Format

Share Document