Synthesis of 5-alkoxythieno[2,3-e][1,2,4]triazolo[4,3-c]pyrimidine derivatives and evaluation of their anticonvulsant activities

Recent Advances in the Development of Pyrimidine-based CNS Agents

BACKGROUND

In the past few decades, considerable progress has been made in CNS drug discovery, and various new CNS agents have been developed. Pyrimidine is an important scaffold in the area of medicinal chemistry. Recently, pyrimidine-containing compounds have been successfully designed as potent CNS agents. Substantial research has been carried out on pyrimidine-bearing compounds to treat different disorders of CNS in various animal models.

METHODS

Utilizing various databases, including Google Scholar, PubMed, Science Direct, and Web of Science, the literature review was conducted. The specifics of significant articles were discussed with an emphasis on the potency of pyrimidines derivatives possessing CNS activity.

RESULTS

Recent papers indicating pyrimidine derivatives with CNS activity were incorporated into the manuscript. (46) to (50) papers included different pyrimidine derivatives as 5-HT agonist/antagonists, (62) to (67) as adenosine agonist/antagonist, (70) to (75) as anticonvulsant agents, (80) to (83) as cannabinoid receptor agonists, (102) to (103) as nicotinic and (110) as muscarinic receptor agonists. The remaining papers (113) to (114) represented pyrimidine-based molecular imaging agents.

CONCLUSION

Pyrimidine and its derivatives have been studied in detail to evaluate their efficacy in overcoming multiple central nervous system disorders. The article covers the current updates on pyrimidine-based compounds as potent CNS and molecular imaging agents and will definitely provide a better platform for the development of potent pyrimidine-based CNS drugs in the near future.

DFT, ADMET and Molecular Docking Investigations for the Antimicrobial Activity of 6,6'-Diamino-1,1',3,3'-tetramethyl-5,5'-(4-chlorobenzylidene)bis[pyrimidine-2,4(1H,3H)-dione]

Heterocyclic compounds, including pyrimidine derivatives, exhibit a broad variety of biological and pharmacological activities. In this paper, a previously synthesized novel pyrimidine molecule is proposed, and its pharmaceutical properties are investigated. Computational techniques such as the density functional theory, ADMET evaluation, and molecular docking were applied to elucidate the chemical nature, drug likeness and antibacterial function of molecule. The viewpoint of quantum chemical computations revealed that the molecule was relatively stable and has a high electrophilic nature. The contour maps of HOMO-LUMO and molecular electrostatic potential were analyzed to illustrate the charge density distributions that could be associated with the biological activity. Natural bond orbital (NBO) analysis revealed details about the interaction between donor and acceptor within the bond. Drug likeness and ADMET analysis showed that the molecule possesses the agents of safety and the effective combination therapy as pharmaceutical drug. The antimicrobial activity was investigated using molecular docking. The investigated molecule demonstrated a high affinity for binding within the active sites of antibacterial and antimalarial proteins. The high affinity of the antibacterial protein was proved by its low binding energy (-7.97 kcal/mol) and a low inhibition constant value (1.43 µM). The formation of four conventional hydrogen bonds in ligand-protein interactions confirmed the high stability of the resulting complexes. When compared to known standard drugs, the studied molecule displayed a remarkable antimalarial activity, as indicated by higher binding affinity (B.E. -5.86 kcal/mol & Ki = 50.23 M). The pre-selected molecule could be presented as a promising drug candidate for the development of novel antimicrobial agents.

An Important Potential Anti-Epileptic/Anticonvulsant Active Group: A Review of 1,2,4-Triazole Groups and Their Action

Epilepsy is one of the most common encountered neurological disorders. Many individuals continue to have seizures despite medical and surgical treatments, suggesting new antiepileptic/anticonvulsant drugs are required. Triazole compounds are widely used in pharmaceuticals and have gained significant importance in medicinal chemistry. This article is an attempt to systematically review the research of triazole derivatives in the design and development of anticonvulsant agents during the past two decades through extensive literature research. The results show that triazole occupy a distinct niche in heterocyclic chemistry and represent a key motif in medicinal chemistry because of their capability to exhibit an array of properties and bioactivities, Therefore, 1,2,4-triazole seems to be an important pharmacophore, especially in the field of antiepileptic, which is of great explored potentiality and utilized value. Through in-depth research on this type of structure, it is believed that more 1,2,4-triazole compounds will be developed as anti-epileptic drugs for clinical use.

Synthesis and Evaluation of Antidepressant Activities of 5-Aryl-4,5-dihydrotetrazolo [1,5-a]thieno[2,3-e]pyridine Derivatives

In this study, we synthetized a series of 5-aryl-4,5-dihydrotetrazolo[1,5-a]thieno[2,3-e]pyridine derivatives containing tetrazole and other heterocycle substituents, i.e., triazole, methyltriazole, and triazolone. The forced swim test (FST) and tail suspension test (TST) were used to evaluate the antidepressant activity of the target compounds. The compound 5-[4-(trifluoromethyl)phenyl]-4,5-dihydrotetrazolo[1,5-a]thieno[2,3-e]pyridine (4i) showed the highest antidepressant activity, with a reduced immobility time of 55.33% when compared with the control group. Using an open-field test, compound 4i was shown to not affect spontaneous activity of mice. The determination of in vivo 5-hydroxytryptamine (5-HT) concentration showed that compound 4i may have an effect in the mouse brain. The biological activities of all synthetized compounds were verified by molecular docking studies. Compound 4i showed significant interactions with residues of the 5-HT1A receptor homology model.

Recent developments on triazole nucleus in anticonvulsant compounds: a review

Epilepsy is one of the common diseases seriously threatening life and health of human. More than 50 million people are suffering from this condition and anticonvulsant agents are the main treatment. However, side effects and intolerance, and a lack of efficacy limit the application of the current anticonvulsant agents. The search for new anticonvulsant agents with higher efficacy and lower toxicity continues to be the focus and task in medicinal chemistry. Numbers of triazole derivatives as clinical drugs or candidates have been frequently employed for the treatment of various types of diseases, which have proved the importance of this heterocyclic nucleus in drug design and discovery. Recently many endeavours were made to involve the triazole into the anticonvulsants design, which have brought lots of active compounds. This work is an attempt to systematically review the research of triazole derivatives in the design and development of anticonvulsant agents during the past two decades.

Synthesis and Pharmacological Evaluation of New 3,4-Dihydroisoquinolin Derivatives Containing Heterocycle as Potential Anticonvulsant Agents

Two novel series of 3,4-dihydroisoquinolin with heterocycle derivatives (4a–t and 9a–e) were synthesized and evaluated for their anticonvulsant activity using maximal electroshock (MES) test and pentylenetetrazole (PTZ)-induced seizure test. All compounds were characterized by IR, ¹H-NMR, ¹³C-NMR, and mass spectral data. Among them, 9-(exyloxy)-5,6-dihydro-[1,2,4]triazolo[3,4-a]isoquinolin-3(2H)-one (9a) showed significant anticonvulsant activity in MES tests with an ED₅₀ value of 63.31 mg/kg and it showed wide margins of safety with protective index (PI > 7.9). It showed much higher anticonvulsant activity than that of valproate. It also demonstrated potent activity against PTZ-induced seizures. A docking study of compound 9a in the benzodiazepine (BZD)-binding site of γ-aminobutyric acid_A (GABA_A) receptor confirmed possible binding of compound 9a with the BZD receptors.