Analgesic study of novel pyrimidine derivatives linked with coumarin moiety

Novel coumarin-chalcone derivatives: Synthesis, characterization, antioxidant, cyclic voltammetry, molecular modelling and biological evaluation studies as acetylcholinesterase, α-glycosidase, and carbonic anhydrase inhibitors

In this study, a total of 12 coumarin-chalcone derivatives, 6 of which are original were synthesized. The structures of the newly synthesized compounds were elucidated by 1H NMR, 13C NMR, IR, and elemental analysis methods (7g-7l). The antioxidant potencies measured by using CUPRAC method (Trolox equivalent total antioxidant capacity) were as follows: 7j > 7i > 7c > 7d > 7k > 7l > 7f > 7h > 7e > 7g > 7a > 7b. Furthermore, the compounds were evaluated against human carbonic anhydrases I, II, acetylcholinesterase and α-glycosidase enzymes. Compounds 7c, 7e, 7g, 7i, 7j and 7l showed promising human carbonic anhydrase I inhibition compared to the standard Acetazolamide (Ki: 16.64 ± 4.72-49.82 ± 5.82 nM vs Ki: 57.64 ± 5.41 nM). In addition, all compounds exhibited strong inhibition against acetylcholinesterase and α-glycosidase. Ki values were between 2.39 ± 0.97-9.35 ± 3.95 nM (Tacrine Ki: 13.78 ± 4.36 nM) for acetylcholinesterase, and 14.49 ± 8.51-75.67 ± 26.38 nM (Acarbose Ki: 12600 ± 78.00 nM) for α-glycosidase. Binding of 7g was predicted using molecular docking and stability of the complex was confirmed with molecular dynamics simulations which shed a light on the observed activity against acetylcholinesterase. Finally, cyclic voltammetry was also used for the electrochemical characterization of the synthesized compounds.

Azole-pyrimidine Hybrid Anticancer Agents: A Review of Molecular Structure, Structure Activity Relationship and Molecular Docking

Cancer has emerged as one of the leading causes of deaths globally partly due to the steady rise in anticancer drug resistance. Pyrimidine and pyrimidine-fused heterocycles are some of the privileged scaffolds in medicine, as they possess diverse biological properties. Pyrimidines containing azole nucleus possesses inestimable anticancer potency and has enormous potential to conduct the regulation of cellular pathways for selective anticancer activity. The present review outlines the molecular structure of pyrimidine-fused azoles with significant anticancer activity. The structure activity relationship and molecular docking studies have also been discussed. The current review is the first complete compilation of significant literature on the proposed topic from 2016 to 2020. The information contained in this review offers a useful insight to chemists in the design of new and potent anticancer azole-pyrimidine analogues.

Antioxidant Activity of Encapsulated Extracts and Bioactives from Natural Sources

The low water solubility and low bioavailability of natural bioactive substances such as polyphenols and flavonoids, either in pure form or extracts, are a major concern in the pharmaceutical field and even on the food development sector. Although encapsulation has demonstrated success in addressing these drawbacks, it is important to evaluate the antioxidant activity of the encapsulated compounds. This article reviews the encapsulation of bioactive compounds from natural sources focusing their antioxidant activity after encapsulation. Attention is given to the methods and wall materials used, and the antioxidant activity methodologies (classical in vitro techniques such as DPPH, ORAC, FRAP and others, as well as in vivo/ex vivo tests to evaluate endogenous antioxidant enzymes or oxidative stress) applied to assess the antioxidant capacity are also comprehensively summarized.

Utility of Lauroyl Isothiocyanate as a Scaffold in the Synthesis of Some Novel Pyrimidine Derivatives and Their Antimicrobial Assessment

The reaction of lauroyl isothiocyanate 1 with enaminonitrile derivative 2 furnished N-(6-cyano-3, 4-diphenylthieno[2,3-c]pyridazin-5-yl-carbamothioyl)dodecanamide 3, which was used as precursor for the synthesis of novel heterocyclic systems. Polyfunctional pyrimidine and fused pyrimidine derivatives were obtained by the cyclization of compound 3 under different basic conditions as well as its reactions with thiourea, o-aminothiophenol, hydrazine hydrate, phenyl hydrazine, ethyl phenyl acetate or ethyl benzoyl acetate. The structures of the new compounds were confirmed by microanalytical and spectral properties. The synthesised compounds were tested in-vitro for their antimicrobial activity and showed congruent results against most of the tested microorganisms compared to the standard drugs Gentamycin and Ketoconazol.

Synthesis and Antimicrobial Evaluation of Thieno[2,3-d]-pyrimidine, Thieno[2',3':4,5]pyrimido[1,2-a][1,3,5]triazine, Thieno[2,3-d]-1,3-thiazine and 1,2,4-Triazole Systems

The reaction of lauroyl isothiocyanate with ethyl 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate gave ethyl 2-(3-dodecanoylthioureido)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate 3. Compound 3 could serve as a main building block in synthesis of the target heterocyclic systems like thieno[2,3-d]-pyrimidine, thieno[2',3':4,5]pyrimido[1,2-a][1,3,5]triazine, thieno[2,3-d]-1,3-thiazine and 1,2,4-triazole systems attached to the lauryl group. The structures of the synthesized target heterocyclic compounds were confirmed by microanalytical and spectral data. The antimicrobial activity of some of the synthesized compounds was tested.

Coumarin-Chalcone Hybrids as Peroxyl Radical Scavengers: Kinetics and Mechanisms

The primary antioxidant activity of coumarin-chalcone hybrids has been investigated using the density functional and the conventional transition state theories. Their peroxyl radical scavenging ability was studied in solvents of different polarity and taking into account different reaction mechanisms. It was found that the activity of the hybrids increases with the polarity of the environment and the number of phenolic sites. In addition, their peroxyl radical scavenging activity is larger than those of the corresponding nonhybrid coumarin and chalcone molecules. This finding is in line with previous experimental evidence. All the investigated molecules were found to react faster than Trolox with (•)OOH, regardless of the polarity of the environment. The role of deprotonation on the overall activity of the studied compounds was assessed. The rate constants and branching ratios for the reactions of all the studied compounds with (•)OOH are reported for the first time.

Microwave-assisted synthesis of new fluorinated coumarin–pyrimidine hybrids as potent anticancer agents, their DNA cleavage and X-ray crystal studies

Rapid and high yielding synthesis of new fluorinated coumarin–pyrimidine hybrids and their application as potent anticancer agents is described.

Pyrimidine containing furanose derivative having antifungal, antioxidant, and anticancer activity

BACKGROUND

A series of 6-(substituted aldehyde)-3,4-dihydro-1-(tetrahydro-3,4-dihydroxy-5-(hydroxymethyl) furan-2-yl)-4-phenylpyrimidine-2(1H)-one derivative (6A-6P) was synthesized from the 6-(substituted aldehyde)-4-phenylpyrimidine-2(1H)-one derivative (5A-5P) through following reaction mechanisms Claisen-Schmidt, Cyclization, and Satos fusion. The structures of the synthesized compounds were elucidated by I.R.,(1)H-NMR, elemental analysis, and mass spectroscopic techniques.

RESULT

The synthesized compounds were screened for in vitro antifungal activity at 25, 50, 100, and 200 μg/ml concentrations. Among them, compounds 6P, 6D, and 6M exhibited significant antifungal activity that was carried out by cup plate method against fungal strain which was collected from IMTECH Chandigarh, India, against standard drug fluconazole. Compounds have been further evaluated by measuring zone of inhibition and percent inhibition. The synthesized compounds were screened for in vitro antioxidant activity using the DPPH assay, based on the AAI and antioxidant activity unit (AAU), using a combination relation between DPPH concentration and absorbance. The antioxidant strength of compounds was compared against ascorbic acid. Among them, compounds 6K, 6F, 6E, 6G, 6H, and 6M exhibited significant antioxidant activity and 6J have less active compound. The data of these synthesized compounds were submitted to the National Institute of Health, USA, under the drug discovery program of National Cancer Institute (NCI) and screened for anticancer activity at a single high dose (10(-5) M) in full NCI 60 cell lines. The selected compounds have shown potent significant anticancer activity in the NCI 60 cell line screening.

CONCLUSION

A new series of pyrimidine analogues that contain furanose moiety were synthesized by Satos fusion and characterized. The synthesized compounds screened for their in vitro antioxidant, antifungal activity, as well as anticancer activity given by the derivative which has chloro, methoxy, nitro, and chloro substitution having furanose contain pyrimidine derivative that showed the most potent activity.