scholarly journals Acetophenone Mannich bases: study of ionic liquid catalysed synthesis and antioxidative potential of products

2018 ◽  
Vol 5 (11) ◽  
pp. 181232 ◽  
Author(s):  
Vladimir P. Petrović ◽  
Dušica Simijonović ◽  
Vesna M. Milovanović ◽  
Zorica D. Petrović
Keyword(s):  
Mannich Reaction ◽  
Density Functional ◽  
Mannich Bases ◽  
Substituted Anilines ◽  
Rate Determining Step ◽  
Water Elimination ◽  
Iminium Ion ◽  
Activity Mechanism ◽  
First Time

Three-component Mannich reaction of acetophenone or 4-iodoacetophenone with a variety of substituted anilines and benzaldehyde, catalysed with diethanolammonium chloroacetate, was performed under mild conditions. Mannich bases ( MBs ), of which five are new, were obtained in good to excellent yields. All compounds were characterized using elemental analysis, NMR and IR. In addition, detailed experimental and simulated UV–Vis spectral characterization of these compounds is presented here for the first time. In vitro antioxidative potential of synthetized MBs was evaluated using 2,2-diphenyl-1-picryl-hydrazyl radical and density functional theory (DFT) thermodynamical study. It was shown that compounds with anisidine moiety express moderate antioxidative activity. Mechanism of the organocatalysed Mannich reaction was thoroughly inspected by means of DFT. The reaction undergoes the hydrogen bonding-assisted mechanism. Moreover, the proposed rate determining step of the overall reaction is water elimination in the process of iminium ion formation. To the extent of our knowledge, this is the first detailed report on the influence of this type of catalyst on the formation of iminium ion, as a crucial intermediate for the whole reaction.

scholarly journals Synthesis, characterization and biological evaluation of some novel N-Mannich bases of heterocyclic 1,3,4-thiadiazole.

2019 ◽  
Vol 9 (4-A) ◽  
pp. 220-228
Author(s):  
Piush Sharma ◽  
Charanjeet Singh
Keyword(s):  
Mannich Reaction ◽  
Mannich Bases ◽  
Biological Evaluation ◽  
Inflammatory Activity ◽  
Albino Rats ◽  
Plate Method ◽  
Standard Drug ◽  
Excellent Activity ◽  
Anti Inflammatory

A series of some novel N-Mannich bases of heterocyclic 1,3,4-thiadiazole were synthesized through the condensation reaction of 1,3,4-thiadiazole containing a aromatic secondary amine, aromatic aldehydes and cyclic compounds employing Mannich reaction and using conventional synthesis. All the synthesized compounds were obtained in the range of 57.41-83.3 % yield. The structures of synthesized compounds were confirmed by UV, IR, 1H NMR spectroscopy. the essential structural features responsible for interaction with receptor site are established within a suggested pharmacophore. The in vitro antibacterial activity of the synthesized compounds was determined, against two Gram-positive bacteria, viz. S. aureus & B. subtilis and Gram-negative, viz. E. coli and K. pneumoniae, by cup-plate method using the standard drug ciprofloxacin. Minimum inhibitory concentrations (MIC) changed in the range of 1.56_ _ 200 mg mL_1. Compound 3b exhibited excellent activity against both bacteria. The in vitro antifungal activity of the synthesized compound was also evaluated by cup-plate method against the fungi A. niger and C. albicans compared with the standard drug Fluconazole. Compound 4a, 8a exhibited excellent activity against both fungi. The result has shown that the compounds are quite active against pathogens under study and were nontoxic. The anti-inflammatory activity of the compound was evaluated, on albino rats, by carageenan induced rat paw oedema method using the standard drug diclofenac sodium. Compound 7b and 8c exhibited excellent anti-inflammatory and analgesic pharmacological activities. Structurally the compound 7b has a greater number of unsaturated hydrocarbons in schiff base, which shows good lipophilic properties within electron rich morpholine ring in Mannich base. Statistical significance of differences between group was determined by one-way analysis of variance (ANOVA). Among the synthesized compounds 3a, 4b, 5c, 7b, 8a and 8c were found be the most active. All the synthesized compounds were found to be low lethal as ascertained by LD50 test. Keywords: N- Mannich bases of heterocyclic 1,3,4-thiadiazole derivatives; Mannich reaction; antimicrobial agents; anti-inflammatory activity;

Synthesis, Transformations and Characterization of 8 Aminomethyl Substituted Umbelliferones as Probable Anti-Arrhythmic Agents

2019 ◽  
Vol 15 (1) ◽  
pp. 71-82 ◽  
Author(s):  
Alla V. Lipeeva ◽  
Arkady O. Brysgalov ◽  
Tatyana G. Tolstikova ◽  
Elvira E. Shults
Keyword(s):  
Mannich Reaction ◽  
Suzuki Reaction ◽  
Mannich Bases ◽  
Pharmacological Agents ◽  
Natural Coumarin ◽  
The Mannich Reaction ◽  
First Time ◽  
Substituted Coumarins

Background: Coumarin and modified nitrogen heterocyclic nuclei show biological activity. Combining these into a hybrid molecule could lead to new pharmacological agents. A series of hybrid compounds combining coumarin and piperidine, piperazine, purine or tetrahydroisoquinoline moieties were synthesized and evaluated for anti-arrhythmic activity. Methods: The Mannich reaction of coumarins (peurutenicin, peucenol and 6-cyanoumbelliferrone) with formaldehyde and various amines, including several alkaloids – anabasine, theophylline or tetrahydroisoquinolines, proceeds by heating under reflux in dioxane in the presence of 4-dimethylaminopyridine. The Suzuki reaction of 6,8-disubstituted umbelliferone triflate was used for the introduction of an aryl substituent in position 7 of the the coumarin framework. Results: Twenty two novel coumarin-based Mannich bases were synthesized via introduction of functional aminomethyl group at position 8 of 6 substituted 7-hydroxy-2H-chromen-2-ones by Mannich reaction. The results illustrated that the C-6 and C-8 substituents’ effect was obvious in our designed system and there was a relationship between the structures and the anti-arrhythmic activity of the 6,7,8- trisubstituted coumarins. 8-(6,7-dimethoxy-1-(3,4,5-trimethoxyphenyl)-tetrahydroisoquinolinylmethyl)- substituted peucenol derivatives shown in vivo a pronounced and selective anti-arrhythmic activity on epinephrine arrhythmias in comparison with natural coumarin peucenol. The moderate toxicity of the new compound encouraged further design of therapeutically relevant analogues based on this novel type of coumarin- tetrahydroisoquinoline hybrids. Conclusion: We have developed a mild reaction protocol to synthesize new mannich products on the basis of substituted coumarins. The anti-arrhythmic activity of coumarin-tetrahydroisoquinoline hybrids was revealed. We report for the first time that coumarin containing 8-(1-(3,4,5-trimethoxyphenyl) tetrahydroisoquinolinyl)methyl) substituent offer a suitable scaffold for the development of novel anti-arrhythmic agents.

scholarly journals Synthesis, density functional theory study and in vitro antimicrobial evaluation of new benzimidazole Mannich bases

BMC Chemistry ◽  
2020 ◽  
Vol 14 (1) ◽  
Author(s):  
Maria Marinescu ◽  
Ludmila Otilia Cinteză ◽  
George Iuliu Marton ◽  
Mariana-Carmen Chifiriuc ◽  
Marcela Popa ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Density Functional ◽  
Mannich Bases ◽  
Density Functional Theory Study ◽  
Functional Theory ◽  
Antimicrobial Evaluation

scholarly journals New Octadecanoid Enantiomers from the Whole Plants of Plantago depressa

Molecules ◽  
2018 ◽  
Vol 23 (7) ◽  
pp. 1723 ◽  
Author(s):  
Xiu-Qing Song ◽  
Kongkai Zhu ◽  
Jin-Hai Yu ◽  
Qianqian Zhang ◽  
Yuying Zhang ◽  
...  
Keyword(s):  
Density Functional ◽  
Ethanolic Extract ◽  
Raw 264.7 Cells ◽  
No Production ◽  
Functional Theory ◽  
Td Dft ◽  
Whole Plants ◽  
New Compounds ◽  
First Time

In this study, 19 octadecanoid derivatives—four pairs of enantiomers (1–8), two racemic/scalemic mixtures (9–10), and nine biosynthetically related analogues—were obtained from the ethanolic extract of a Chinese medicinal plant, Plantago depressa Willd. Their structures were elucidated on the basis of detailed spectroscopic analyses, with the absolute configurations of the new compounds assigned by time-dependent density functional theory (TD-DFT)-based electronic circular dichroism (ECD) calculations. Six of them (1, 3–6, and 9) were reported for the first time, while 2, 7, and 8 have been previously described as derivatives and are currently obtained as natural products. Our bioassays have established that selective compounds show in vitro anti-inflammatory activity by inhibiting lipopolysaccharide-induced nitric oxide (NO) production in mouse macrophage RAW 264.7 cells.

1,3-Bis(trifluoromethyl)prop-2-ene 1-Iminium Salts ‒ Reactions with Alkoxybenzenes and Anilines

Synthesis ◽  
2021 ◽  
Author(s):  
Michael Keim ◽  
Medina Jasarevic ◽  
Ines Miller ◽  
Gerhard Maas
Keyword(s):  
Condensation Product ◽  
Building Blocks ◽  
Substituted Anilines ◽  
Iminium Salts ◽  
Iminium Ion ◽  
First Time

1,3-Bis(trifluoromethyl)prop-2-ene 1-iminium triflate salts were prepared for the first time and some synthetic applications as 1,3-biselectrophilic building blocks were established. They were found to react with dimethoxybenzenes or methylene-1,2-dioxybenzenes to furnish vinylogous trifluoroacetylaton products (4-aryl-1,1,1,5,5,5-hexafluoropent-3-en-2-ones) and 1-dialkylamino-1,3-bis(trifluoromethyl)-1H-indenes. With aniline and ring-substituted anilines, 2,4-bis(trifluoromethyl)quinolines were formed. An unusual 4H-pyran, formally a condensation product of the N,N-dimethyl-1,3-bis(trifluoromethyl)prop-2-en-1-iminium ion and its enaminone precursor, is also reported.

Somatic Embryogenesis and In vitro Plant Regeneration in Vigna trilobata (L.) Verd. - A Potential Pasture Legume

1970 ◽  
Vol 19 (1) ◽  
pp. 89-99
Author(s):  
K. Choudhary ◽  
M. Singh ◽  
M. S. Rathore ◽  
N. S. Shekhawat
Keyword(s):  
Somatic Embryogenesis ◽  
Growth Regulators ◽  
Somatic Embryos ◽  
Basal Medium ◽  
Long Term Study ◽  
Continuous Application ◽  
First Time ◽  
Pasture Legume

This long term study demonstrates for the first time that it is possible to propagate embryogenic Vigna trilobata and to subsequently initiate the differentiation of embryos into complete plantlets. Initiation of callus was possible on 2,4-D. Somatic embryos differentiated on modified MS basal nutrient medium with 1.0 mg/l  of 2,4-D and 0.5 mg/l  of Kn. Sustained cell division resulted in globular and heart shape stages of somatic embryos. Transfer of embryos on to a fresh modified MS basal medium with 0.5 mg/l of Kn and 0.5 mg/l of GA3 helped them to attain maturation and germination. However, the propagation of cells, as well as the differentiation of embryos, were inhibited by a continuous application of these growth regulators. For this reason, a long period on medium lacking these growth regulators was necessary before the differentiation of embryos occurred again. The consequences for improving the propagation of embryogenic cultures in Vigna species are discussed. Key words: Pasture  legume, Vigna trilobata, Globular, Heart shape, somatic embryogenesis D.O.I. 10.3329/ptcb.v19i1.4990 Plant Tissue Cult. & Biotech. 19(1): 89-99, 2009 (June)

Dwindling status of Epimedium Elatum (Morren & Decne) and its geographical distribution in Kashmir Himalaya, India

2018 ◽  
pp. 47-52
Keyword(s):  
Medicinal Plant ◽  
Biological Activities ◽  
Conservation Status ◽  
Natural Populations ◽  
Culture Techniques ◽  
Kashmir Himalayas ◽  
Near Future ◽  
First Time ◽  
Tissue Culture Techniques

Epimedium elatum (Morren & Decne) of family Berberidaceace is a rare perennial medicinal plant, endemic to high altitude forests of Northwestern Himalayas in India. Ethnobotanically, it has been used as an ingredient for treatment of bone-joint disorders, impotence and kidney disorders in Kashmir Himalayas. Phytochemically, it is rich in Epimedin ABC and Icariin; all of these have been demonstrated to possess remarkable biological activities like PDE-5 inhibition (treatment of erectile dysfunction), anticancer, antiosteoporosis antioxidant and antiviral properties. The present investigation reports its traditional usage, comprehensive distribution and conservation status from twenty ecogeographical regions in Kashmir Himalayas, India. The species was reported from Gurez valley for the first time. Numerous threats like excessive grazing, deforestration, habitat fragmentation, tourism encroachment, landslides and excessive exploitation have decreased its natural populations in most of the surveyed habitats. Consequently, its existence may become threatened in near future if timely conservation steps are not taken immediately by concerned stakeholders involved in medicinal plant research. Moreover, use of plant tissue culture techniques is recommended for development of its in vitro propagation protocols. Therefore, introduction of this medicinal plant in botanical gardens, protected sites and development of monitoring programmes are needed for its immediate conservation in Northwestern Himalayas, India.

Structure-Reactivity Relationships on Substrates and Inhibitors of the Lysine Deacylase Sirtuin 2 from Schistosoma Mansoni (SmSirt2)

2019 ◽  
Author(s):  
Daria Monaldi ◽  
Dante Rotili ◽  
Julien Lancelot ◽  
Martin Marek ◽  
Nathalie Wössner ◽  
...  
Keyword(s):  
Schistosoma Mansoni ◽  
Human Cancer ◽  
Egg Laying ◽  
Human Cancer Cells ◽  
Parasite Survival ◽  
Survival And Reproduction ◽  
Emergence Of Resistance ◽  
First Time ◽  
Parasitic Life Cycle

The only drug for treatment of Schistosomiasis is Praziquantel, and the possible emergence of resistance makes research on novel therapeutic agents necessary. Targeting of Schistosoma mansoni epigenetic enzymes, which regulate the parasitic life cycle, emerged as promising approach. Due to the strong effects of human Sirtuin inhibitors on parasite survival and reproduction, Schistosoma sirtuins were postulated as therapeutic targets. In vitro testing of synthetic substrates of S. mansoni Sirtuin 2 (SmSirt2) and kinetic experiments on a myristoylated peptide demonstrated lysine long chain deacylation as an intrinsic SmSirt2 activity for the first time. Focused in vitro screening of the GSK Kinetobox library and structure-activity relationships (SAR) of identified hits, led to the first SmSirt2 inhibitors with activity in the low micromolar range. Several SmSirt2 inhibitors showed potency against both larval schistosomes (viability) and adult worms (pairing, egg laying) in culture without general toxicity to human cancer cells.<br>

α-Glucosidase Inhibition and Docking Studies of 5-Deoxyflavonols and Dihydroflavonols Isolated from Abutilon pakistanicum

2019 ◽  
Vol 23 (17) ◽  
pp. 1857-1866
Author(s):  
Munawar Hussain ◽  
Zaheer Ahmed ◽  
Shamsun N. Khan ◽  
Syed A. A. Shah ◽  
Rizwana Razi ◽  
...  
Keyword(s):  
Methanolic Extract ◽  
Docking Studies ◽  
Hydroxyl Group ◽  
Coumaric Acid ◽  
In Vitro Activity ◽  
Aerial Parts ◽  
First Time ◽  
Acid Esters ◽  
Phenol Moiety

Three new 5-deoxyflavonoid and dihydroflavonoids 2, 3 and 4 have been isolated from the methanolic extract of Abutioln pakistanicum aerial parts, for which structures were elucidated explicitly by extensive MS- and NMR-experiments. In addition to these, 3,7,4′-trihydroxy-3′-methoxy flavonol (1) is reported for the first time from Abutioln pakistanicum. Compound 2 and 4 are p-coumaric acid esters while compounds 2–4 exhibited α-glucosidase inhibitory activity. Docking studies indicated that the ability of flavonoids 2, 3 and 4 to form multiple hydrogen bonds with catalytically important residues is decisive hence is responsible for the inhibition activity. The docking results signified the observed in-vitro activity quite well which is in accordance with previously obtained conclusion that phenol moiety and hydroxyl group are critical for the inhibition of α-glucosidase enzyme.

Molecular Investigations of the Newly Synthesized Azomethines as Antioxidants: Theoretical and Experimental Studies

2019 ◽  
Vol 19 (6) ◽  
pp. 419-433 ◽  
Author(s):  
Siyamak Shahab ◽  
Masoome Sheikhi ◽  
Liudmila Filippovich ◽  
Evgenij Dikusar ◽  
Anhelina Pazniak ◽  
...  
Keyword(s):  
Density Functional ◽  
Energy Gap ◽  
Experimental Studies ◽  
Antioxidant Property ◽  
Nbo Analysis ◽  
Antioxidant Potential ◽  
Functional Theory ◽  
Homo And Lumo ◽  
Intramolecular Hydrogen ◽  
Activity Mechanism

: In this study, the antioxidant property of new synthesized azomethins has been investigated as theoretical and experimental. Methods and Results: Density functional theory (DFT) was employed to investigate the Bond Dissociation Enthalpy (BDE), Mulliken Charges, NBO analysis, Ionization Potential (IP), Electron Affinities (EA), HOMO and LUMO energies, Hardness (η), Softness (S), Electronegativity (µ), Electrophilic Index (ω), Electron Donating Power (ω-), Electron Accepting Power (ω+) and Energy Gap (Eg) in order to deduce scavenging action of the two new synthesized azomethines (FD-1 and FD-2). Spin density calculations and NBO analysis were also carried out to understand the antioxidant activity mechanism. Comparison of BDE of FD-1 and FD-2 indicate the weal antioxidant potential of these structures. Conclusion: FD-1 and FD-2 have very high antioxidant potential due to the planarity and formation of intramolecular hydrogen bonds.

Sign in / Sign up

Export Citation Format

Share Document