Synthesis and anticonvulsant activity of a new 6-alkoxy-[1,2,4]triazolo[4,3-b]pyridazine

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.

Developments in the Application of 1,2,3-Triazoles in Cancer Treatment

BACKGROUND

The impact of cancer on modern society cannot be emphasized enough in terms of both economic and human costs. Cancer treatments are known, unfortunately, for their side effects - frequently numerous and severe. Drug resistance is another issue medical professionals have to tackle when dealing with neoplastic illnesses. Cancer rates are rising worldwide due to various factors - low-quality nutrition, air and water pollution, tobacco use, etc. For those and many other reasons, drug discovery in the field of oncology is a top priority in modern medical science.

OBJECTIVE

To present the reader with the latest in cancer drug discovery with regard to 1,2,3-triazole- containing molecules in a clear, concise way so as to make the present review a useful tool for researchers.

METHODS

Available information present on the role of 1,2,3-triazoles in cancer treatment was collected. Data was collected from scientific literature, as well as from patents.

RESULTS

A vast number of triazole-containing molecules with antiproliferative properties have been proposed, synthesized and tested for anticancer activity both in vitro and in vivo. The substances vary greatly when considering molecular structure, proposed mechanisms of action and affected cancer cell types.

CONCLUSION

Triazole-containing molecules with anticancer activity are being widely synthesized and extensively tested. They vary significantly in terms of both structure and mechanism of action. The methods for their preparation and administration are well established and with proven reproducibility. These facts suggest that triazoles may play an important role in the discovery of novel antiproliferative medications with improved effectiveness and safety profile.

An insight on medicinal attributes of 1,2,4-triazoles

The present review aims to summarize the pharmacological profile of 1,2,4-triazole, one of the emerging privileged scaffold, as antifungal, antibacterial, anticancer, anticonvulsant, antituberculosis, antiviral, antiparasitic, analgesic and anti-inflammatory agents, etc. along with structure-activity relationship. The comprehensive compilation of work carried out in the last decade on 1,2,4-triazole nucleus will provide inevitable scope for researchers for the advancement of novel potential drug candidates having better efficacy and selectivity.

Synthetic and therapeutic perspectives of nitrogen containing heterocycles as anti-convulsants

Epilepsy is one of the commonly prevailing neurological disorders. According to the reports, it is evident that about 80% of the epileptic cases have been observed in developing countries. Although there are many drugs with significant potency available in the market; still there is an issue of selectivity and toxicity. Therefore, continuous attempts have been made by the researchers to develop newer therapeutic agents against epilepsy. Many synthetic strategies have been available in the literature to synthesize various classes of anticonvulsants with promising activity. In the presented review, authors have summarized some newer synthetic routes being used for the synthesis of nitrogen-containing anticonvulsants taking a cue from the reported established anticonvulsant drugs viz. vigabatrin, sodium valproate, oxcarbazepine, felbamate, retigabine, and gabapentin. Various derivatives with the substitution for better anticonvulsant profile have been described in the figures for easy comparative study. The structure-activity relationship (SAR) of compounds with maximum potency has also been discussed. This article may serve as a boost for the researchers to modify the pre-existing synthetic routes as well as to improve potency and yield of the compounds.

Exploring the Role of Consecutive Addition of Nitrogen Atoms on Stability and Reactivity of Hydrogen-Bonded Azine-Water Complexes

The second-order Møller-Plesset perturbation theory (MP2) and density functional theory with dispersion function calculations have been applied to investigate the hydrogen-bonding interaction between azines and water. The study suggests that the ability of nitrogen present in azine to act as a hydrogen-bond acceptor decreases in the order of pyridine (PY) > diazine (DZ) > triazine (TZ) > tetrazine (TTZ) > pentazine (PZ) > hexazine (HZ). Natural bond orbital (NBO) analysis, atoms in molecules, symmetry-adapted perturbation theory (SAPT), and molecular electrostatic potential studies reflect the factors important for hydrogen-bond strength as well as for the structural, electronic, and vibrational changes occurring during complexation. NBO analysis reflects that upon gradual addition of nitrogen atoms, hyperconjugation leads to an increase in the population of antibonding O-H bond, thus causing elongation and weakening of O-H bond in complexes incorporating N···H-O_W interaction, whereas rehybridization leads to an increase in the s character of the carbon hybrid orbital in C-H bond, thus causing contraction and shortening of C-H bond in complexes having C-H···O_W interactions. From the topological analysis, an excellent linear correlation is found to exist between stabilization energy (ΔE _BSSE), electron density (ρ_c), and its Laplacian (∇²ρ_c) at the bond critical points.

Glycerol and Q-Tubes: Green Catalyst and Technique for Synthesis of Polyfunctionally Substituted Heteroaromatics and Anilines

The role of glycerol as a green bio-based solvent, reactant, and/or a catalyst in the synthesis of novel heterocycles, under pressure, is studied. Synthesis of novel quinolines in good yields using a new modified Skraup synthesis, utilizing glycerol and pressure Q-tubes, is demonstrated. Novel aniline trimers are prepared using glycerol, and substituted anilines under pressure, in acidic medium and water. Glycerol was employed as a catalyst and a green solvent in the synthesis of novel pyridazines 13a-c. The mechanisms of the reactions and the catalytic effect of glycerol in protic and aprotic media are fully discussed. The structures of the synthesized compounds were determined via X-ray crystallography and spectroscopic methods.

in vitro Cytotoxic Evaluation of Some New Synthesized Pyridazine Derivatives

A series of novel pyridazine, pyrazoles, pyrimidines derivatives have been synthesized through the reaction of chloropyridazine (1) with p-phenylenediamine to give compound 2. Diazotization of compound 2 followed by coupling with active methylene compounds namely acetylacetone, ethylcyanoacetate and/or ethylacetoacetate afforded novel hydrazons derivatives (4-6). The resulting hydrazons can have been cyclized using hydrazine hydrate and guanidine gave the corresponding pyrazoles (7-9) and pyimidine (10) derivatives. Reaction of compound 2 with acrylonitrile, aromatic aldehyde, p-chloroacetophenone and phenyl isothiocyanate gave compounds 11, 12a, 12b, 13 and 17, respectively. The latter compounds have been used in synthesis of some heterocyclic compounds. The cytotoxic activity of the most active compounds was assessed in vitro against breast carcinoma cell line (MCF-7), human liver cancer cell line (HEPG2), human colon cancer cell line (HCT). Compounds 4, 8 showed best activity against MCF-7 cell line, compounds 5, 13a showed best activity against HePG2 cell line and compound 10 showed best activity against HCT cell line.

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 Bioevaluation of 3,6-Diaryl-[1,2,4]triazolo[4,3-b] Pyridazines as Antitubulin Agents

A series of 3,6-diaryl-[1,2,4]triazolo[4,3-b]pyridazines were designed as a class of vinylogous CA-4 analogues. The easily isomerized (Z,E)-butadiene linker of vinylogous CA-4 was replaced by a rigid [1,2,4]triazolo[4,3-b]pyridazine scaffold. Twenty-one target compounds were synthesized and exhibited moderate to potent antiproliferative activity. The compound 4q with a 3-amino-4-methoxyphenyl moiety as the B-ring, comparable to CA-4 (IC₅₀ = 0.009-0.012 μM), displayed the highly active antiproliferative activity against SGC-7901, A549, and HT-1080 cell lines with IC₅₀ values of 0.014, 0.008, and 0.012 μM, respectively. Tubulin polymerization experiments indicated that 4q effectively inhibited tubulin polymerization, and immunostaining assay revealed that 4q significantly disrupted tubulin microtubule dynamics. Moreover, cell cycle studies revealed that compound 4q dramatically arrested cell cycle progression at G2/M phase in A549 cells. Molecular modeling studies showed that 4q could bind to the colchicine binding site on microtubules.

The importance of triazole scaffold in the development of anticonvulsant agents

Epilepsy is one of the most important neurological disorders with high prevalence worldwide. Many epileptic patients are not completely treated with available drugs and need multiple therapies. Also, many antiepileptic drugs have shown unwanted side effects and drug interactions. Therefore there are continuing interests to find new anticonvulsant drugs. Triazole ring has been found in the structure of many compounds with diverse biological effects. Due to the success of several triazole-containing drugs that entered the pharmaceutical market as CNS-active drugs, this class of heterocyclic compounds has great importance for discovery and development of new anticonvulsant drugs. In this article, we have tried to summarize the latest efforts which have been made in the design and development of triazole-derived anticonvulsant agents.

Synthesis of New Derivatives of Pyridazino[6,1-c]Pyrimido[5,4-e][1,2,4]Triazine; a Novel Heterocyclic System

Several derivatives of the novel pyridazino[6,1-c]pyrimido[5,4-e][1,2,4]triazine ring system have been synthesised through heterocyclisation of 5-bromo-2,4-dichloro-6-methylpyrimidine with 3-chloro-6-hydrazinylpyridazine followed by treatment with secondary amines in boiling ethanol.

Current Research on Antiepileptic Compounds

Epilepsy affects about 1% of the world’s population. Due to the fact all antiepileptic drugs (AEDs) have some undesirable side effects and about 30% of epileptic patients are not seizure-free with the existing AEDs, there is still an urgent need for the development of more effective and safer AEDs. Based on our research work on antiepileptic compounds and other references in recent years, this review covers the reported work on antiepileptic compounds which are classified according to their structures. This review summarized 244 significant anticonvulsant compounds which are classified by functional groups according to the animal model data, although there are some limitations in the data. This review highlights the properties of new compounds endowed with promising antiepileptic properties, which may be proven to be more effective and selective, and possibly free of unwanted side effects. The reviewed compounds represent an interesting possibility to overcome refractory seizures and to reduce the percentage of patients with a poor response to drug therapy.

Synthesis and In Vitro Biological Evaluation of 1,3,4-Oxadiazol-2(3H)-one and Tetrahydropyridazine-3,6-dione Derivatives of Fatty Acids

Herein we report saturated and unsaturated fatty acid derivatives of 1,3,4-oxadiazol-2(3H)-one and tetrahydropyridazine-3,6-dione as new potential anticancer agents. All the synthesised compounds were characterised by IR, ¹H-NMR, ¹³C-NMR, and mass spectral data. The relative sensitivity of three cancer cell lines varied depending on the nature of the compound. Among the most effective anticancer compounds studied, 3b and 6b displayed remarkable anticancer activity against the MDA-MB-231 and KCL-22 lines, respectively. On the other hand, compound 3c was found to be most sensitive to nearly all the tested cell lines, MDA-MB-231, KCL-22, and HeLa.

Synthesis and pharmacological activities of some new triazolo- and tetrazolopyrimidine derivatives

A new series of fused triazolo- and tetrazolopyrimidine derivatives 2-14 were synthesized and their anti-inflammatory and ulcerogenic activities were evaluated. The pharmacological screening showed that many of these obtained compounds have good anti-inflammatory activities, comparable to the reference drug. The toxicity of the compounds was also assayed via the determination of their LD50 values. The structures of newly synthesized compounds were confirmed by IR, 1H-NMR, MS spectral data and elemental analysis.