ChemInform Abstract: Catalyst-Free Mannich Reaction of Hydroxyanthraquinone: Facile Access to Emodin Mannich Bases and Anthraoxazines.

ChemInform ◽  
2013 ◽  
Vol 44 (36) ◽  
pp. no-no
Author(s):  
Li-Ming Zhao ◽  
Li-Ming Zhang ◽  
Feng-Yan Ma ◽  
Xiang-Shan Wang ◽  
Hai-Shan Jin
2013 ◽  
Vol 54 (22) ◽  
pp. 2802-2805 ◽  
Author(s):  
Li-Ming Zhao ◽  
Li-Ming Zhang ◽  
Feng-Yan Ma ◽  
Xiang-Shan Wang ◽  
Hai-Shan Jin

2020 ◽  
Vol 16 (4) ◽  
pp. 531-543
Author(s):  
Shaheen Faizi ◽  
Tahira Sarfaraz ◽  
Saima Sumbul ◽  
Almas Jabeen ◽  
Sobia A. Halim ◽  
...  

Background: In continuation of our work on Mannich reaction on 8-hydroxyquinoline, fifteen different combinations of aromatic aldehydes and aniline were subjected to Mannich reaction from which twelve products (eight Mannich bases, two imines and two intramolecularly cyclized products with benzofuranone skeleton) were obtained. Among them six compounds (1, 2, 6, 8, 9 and 12) are the new compounds. The structures of the compounds were characterized by UV, IR, MS and 1H NMR. Method: The compounds were tested for the inhibition of pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and Interleukin-1β (IL-1β) at a concentration of 25 µg/mL. The cytokines were produced by THP-1 cells differentiated with PMA for 24hrs and stimulated with LPS for 4 hrs and supernatant were analyzed through ELISA technique. Results and Discussion: Compounds 1-5, 8 and 9 inhibited the production of TNF-α and IL-1β. Compounds 1, 3, and 8 exerted potent inhibitions of TNF-α with 71%, 71%, and 83% inhibition, respectively. Compounds 1 and 8 significantly inhibited the production of IL-1β with 64% and 78% inhibition, respectively. Conclusion: Compounds 1 and 8 significantly inhibited the production of IL-1β with 64% and 78% inhibition, respectively. Notably compound 8 showed the most potent inhibition of these cytokines. Additionally, the effect of compounds on viability of THP-1 cells was also evaluated. Moreover, molecular docking was carried out to study the mechanism of inhibition of TNF-α production.


2019 ◽  
Vol 9 (4-A) ◽  
pp. 220-228
Author(s):  
Piush Sharma ◽  
Charanjeet Singh

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;


1987 ◽  
Vol 42 (1) ◽  
pp. 94-96 ◽  
Author(s):  
M. Hammouda ◽  
W. S. Hamama ◽  
E. M. Afsah

Abstract Mannich reaction of the title compound 1 with formaldehyde and morpholine, piperidine or piperazine afforded the Mannich bases 3-5 respectively, whereas the indeno[1.2-d]pyrimidines (6-7) were obtained where primary amines were used. Treatment of 2 with formaldehyde gave benz[b]indeno-diazepine (8). The reaction of formaldehyde with 1 was also investigated.


2013 ◽  
Vol 816-817 ◽  
pp. 1197-1201 ◽  
Author(s):  
Naveen P.Badiger ◽  
I.M. Khazi

A series of 2-(4-methoxybenzyl)-6-aryl-5-pyrrolidin/piperidin/morpholin-1-ylmethyl-imidazo [2,1-[1,3, thiadiazoles (3a-e, 4a-e & 5a-e) were synthesized by Mannich reaction by condensing 2-(4-methoxybenzyl)-6-arylimidazo [2,1-[1,3,thiadiazoles with pyrrolidine, piperidine and morpholine. The title compounds were screened for antitubercular activity againstMycobacterium tuberculosisH37Rv using the BACTEC 460 radiometric assay. Mannich bases with pyrrolidine substitution were found to be most active antitubercular agents. It proves that as the ring size decreases it becomes much potent in its activity. Pyrrolidine being 5 membered ring structure & further combined with imidazothiadiazole nucleus enhances the pharmacological activity.


1976 ◽  
Vol 31 (6) ◽  
pp. 865-869 ◽  
Author(s):  
A. F. A. Shalaby ◽  
H. A. Daboun ◽  
S. S. M. Boghdadi

1-Phenyl-4-thiohydantoin reacted with aryldiazonium salts to give the corresponding5-arylazo-1-phenyl-4-thiohydantoin (1 a-f). On alkylation of 1 a, b,f with different alkyl halides, the corresponding 4-alkylmercapto derivatives (2a-f) were obtained. 2 a was hydrolysed with a mixture of ethanol-hydrochloric acid to give 5-phenylazo-1-phenyl-hydantoin (3). Treatment of 2 a, d with amines gave the products 4a—h. 4 a when refluxed with a mixture of acetic-hydrochloric acid, the product 3 was obtained, 1a, b reacted with formaldehyde and appropriate amine to give the corresponding Mannich bases 5 a-k. Also 1-phenyl-4-thiohydantoin when exposed to the Mannich reaction, 6a-e were obtained, 6 a when treated with benzenediazonium chloride, the colour substance 5 a was separated.


2020 ◽  
Vol 17 ◽  
Author(s):  
Jia-Qi Di ◽  
Hao-Jie Wang ◽  
Zhen-Shui Cui ◽  
Jin-Yong Hu ◽  
Zhan-Hui Zhang

Objective: Aminomethylphenol molecules have wider applications in pharmaceuticals, agrochemicals, plant protection and promising functional materials. The development of an efficient and practical method to prepare this class of compound is highly desirable from both environmental and economical points of views. Materials and Methods: In order to establish an effective synthetic method for preparing aminomethylphenol derivatives, the Petasis borono-Mannich reaction of salicylaldehyde, phenylboronic acid and 1,2,3,4-tetrahydroisoquinoline was selected as a model reaction. A variety of reaction conditions are investigated including solvent and temperature. The generality and limitation of the established method were also evaluated. Results and Discussion: It was found that model reaction can be carried out in cyclopentyl methyl ether at 80 oC under catalyst-free condition. This protocol with a broad substrate applicability, the reaction of various arylboronic acid, secondary amine and salicylaldehyde proceeded smoothly under optimal reaction conditions to afforded various aminomethylphenol derivatives in high yields. A practical, scalable, and high-yielding synthesis of aminomethylphenol derivatives was successfully accomplished. Conclusion: A catalyst-free practical method for the synthesis of minomethylphenol derivatives based on Petasis borono– Mannich (PBM) reaction of various arylboronic acid, secondary amine and salicylaldehyde in cyclopentyl methyl ether has been developed. The salient features of this protocol are avoidance of any additive/catalyst and toxic organic solvents, use cyclopentyl methyl ether as the reaction medium, clean reaction profiles, easy operation, and high to excellent yield.


2019 ◽  
Vol 15 (1) ◽  
pp. 71-82 ◽  
Author(s):  
Alla V. Lipeeva ◽  
Arkady O. Brysgalov ◽  
Tatyana G. Tolstikova ◽  
Elvira E. Shults

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.


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