Hybrids of Benzimidazole-Oxadiazole: A New Avenue for Synthesis, Pharmacological Activity and Recent Patents for the Development of More Effective Ligands.

BACKGROUND: Two significant families of compounds i.e. 1,3,4-oxadiazole and ben-zimidazole, have undergone extensive investigation into their pharmacological characteristics and possible therapeutic applications. Both classes have shown their potential in a variety of ap-plications, and because of their synergistic interactions, they may have an even better therapeutic impact when combined. OBJECTIVES: To produce a specific molecule with potent therapeutic properties, it is now common methods to combine at least two pharmacophores. This facilitates interaction with several targets, enhances biological functions, or eliminates adverse effects associated with them. CONCLUSION: The synthesis of benzimidazole-1,3,4-oxadiazole hybrid compounds has recently involved the use of several synthetic techniques, all of which are detailed in the literature along with the advantages and disadvantages. It has been noted that the structure-activity relationship relates their pharmacological actions to their molecular structure. In order to set the stage for future research, the study aims to provide researchers with an effective toolbox and an under-standing of benzimidazole and 1,3,4-oxadiazole hybrid compounds.

Synthesis, Anticancer Activity, and In Silico Studies of 5-(3-Bromophenyl)-N-aryl-4H-1,2,4-triazol-3-amine Analogs.

In the current study, we described the synthesis of ten new 5-(3-Bromophenyl)-N-aryl-4H-1,2,4-triazol-3-amine analogs (4a-j), as well as their characterization, anticancer activity, molecular docking studies, ADME, and toxicity prediction. The title compounds (4a-j) were prepared in three steps, starting from substituted anilines in a satisfactory yield, followed by their characterization via spectroscopic techniques. The National Cancer Institute (NCI US) protocol was followed to test the compounds' (4a-j) anticancer activity against nine panels of 58 cancer cell lines at a concentration of 10-5 M, and growth percent (GP) as well as percent growth inhibition (PGI) were calculated. Some of the compounds demonstrated significant anticancer activity against a few cancer cell lines. The CNS cancer cell line SNB-75, which showed a PGI of 41.25 percent, was discovered to be the most sensitive cancer cell line to the tested compound 4e. The mean GP of compound 4i was found to be the most promising among the series of compounds. The five cancer cell lines that were found to be the most susceptible to compound 4i were SNB-75, UO-31, CCRF-CEM, EKVX, and OVCAR-5; these five cell lines showed PGIs of 38.94, 30.14, 26.92, 26.61, and 23.12 percent, respectively, at 10-5 M. The inhibition of tubulin is one of the primary molecular targets of many anticancer agents; hence, the compounds (4a-j) were further subjected to molecular docking studies looking at the tubulin-combretastatin A-4 binding site (PDB ID: 5LYJ) of tubulin. The binding affinities were found to be efficient, ranging from -6.502 to -8.341 kcal/mol, with two major electrostatic interactions observed: H-bond and halogen bond. Ligand 4i had a binding affinity of -8.149 kcal/mol with the tubulin-combretastatin A-4 binding site and displayed a H-bond interaction with the residue Asn258. The ADME and toxicity prediction studies for each compound were carried out using SwissADME and ProTox-II software. None of the compounds' ADME predictions showed that they violated Lipinski's rule of five. All of the compounds were also predicted to have LD50 values between 440 and 500 mg/kg, putting them all in class IV toxicity, according to the toxicity prediction. The current discovery could potentially open up the opportunity for further developments in cancer.

Significant Advancement in Various Synthetic Strategies and Pharmacotherapy of Piperine Derivatives: A Review.

BACKGROUND: Piperine is a natural compound found in black pepper that has been traditionally used for various therapeutic purposes. In the ayurvedic system of medication there is a lot of evidence which shows that the piperine is widely used for different therapeutic purpose. In recent years, there has been an increasing interest in the pharmacological and therapeutic potential of piperine and its derivatives in modern medicine. In order to increase the bioavailability and therapeutic effectiveness of piperine and its analogs, researchers have been looking at various extraction methods and synthesis approaches. Many studies have been conducted in this area because of the promise of piperine as a natural substitute for synthetic medications. OBJECTIVES: The objective of this review article is to provide an up-to-date analysis of the literature on the synthesis of piperine analogs, including their extraction techniques and various biological activities such as antihypertensive, antidiabetic, insecticidal, antimicrobial, and antibiotic effects. Additionally, the review aims to discuss the potential of piperine in modern medicine, given its traditional use in various medicinal systems such as Ayurveda, Siddha, and Unani. The article also provides a comprehensive analysis of the plant from which piperine is derived. CONCLUSION: This review article provides a thorough examination of piperine and the source plant. The best extraction technique for the extraction of piperine and the synthesis of its analogs with various biological activities, including antihypertensive, antidiabetic, insecticidal, antibacterial, and antibiotic properties, are covered in the article. This review aims to provide an updated analysis of the literature on the synthesis of piperine analogs.

Design, Synthesis, ADME, and Anticancer Studies of Newer N-Aryl-5-(3,4,5-Trifluorophenyl)-1,3,4-Oxadiazol-2-Amines: An Insight into Experimental and Theoretical Investigations.

In continuance of our investigation into the anticancer activity of oxadiazoles, we report here the preparation of 10 new 1,3,4-oxadiazole analogues using the scaffold hopping technique. We have prepared the oxadiazoles having a common pharmacophoric structure (oxadiazole linked aryl nucleus) as seen in the reported anticancer agents IMC-038525 (tubulin inhibitor), IMC-094332 (tubulin inhibitor), and FATB (isosteric replacement of the S of thiadiazole with the O of oxadiazole). All of the oxadiazole analogues were predicted for their absorption, distribution, metabolism, and excretion (ADME) profiles and toxicity studies. All of the compounds were found to follow Lipinski's rule of 5 with a safe toxicity profile (Class IV compound) against immunotoxicity, mutagenicity, and toxicity. All of the compounds were synthesized and characterized using spectral data, followed by their anticancer activity tested in a single-dose assay at 10 µM as reported by the National Cancer Institute (NCI US) Protocol against nearly 59 cancer cell lines obtained from nine panels, including non-small-cell lung, ovarian, breast, central nervous system (CNS), colon, leukemia, prostate, and cancer melanoma. N-(2,4-Dimethylphenyl)-5-(3,4,5-trifluorophenyl)-1,3,4-oxadiazol-2-amine (6h) displayed significant anticancer activity against SNB-19, OVCAR-8, and NCI-H40 with percent growth inhibitions (PGIs) of 86.61, 85.26, and 75.99 and moderate anticancer activity against HOP-92, SNB-75, ACHN, NCI/ADR-RES, 786-O, A549/ATCC, HCT-116, MDA-MB-231, and SF-295 with PGIs of 67.55, 65.46, 59.09, 59.02, 57.88, 56.88, 56.53, 56.4, and 51.88, respectively. The compound 6h also registered better anticancer activity than Imatinib against CNS, ovarian, renal, breast, prostate, and melanoma cancers with average PGIs of 56.18, 40.41, 36.36, 27.61, 22.61, and 10.33, respectively. Molecular docking against tubulin, one of the appealing cancer targets, demonstrated an efficient binding within the binding site of combretastatin A4. The ligand 6h (docking score = -8.144 kcal/mol) interacted π-cationically with the residue Lys352 (with the oxadiazole ring). Furthermore, molecular dynamic (MD) simulation studies in complex with the tubulin-combretastatin A4 protein and ligand 6h were performed to examine the dynamic stability and conformational behavior.

Synthesis and Anticancer Evaluation of 4-Chloro-2-((5-aryl-1,3,4-oxadiazol-2-yl)amino)phenol Analogues: An Insight into Experimental and Theoretical Studies.

We report herein the synthesis, docking studies and biological evaluation of a series of new 4-chloro-2-((5-aryl-1,3,4-oxadiazol-2-yl)amino)phenol analogues (6a-h). The new compounds were designed based on the oxadiazole-linked aryl core of tubulin inhibitors of IMC-038525 and IMC-094332, prepared in five steps and further characterized via spectral analyses. The anticancer activity of the compounds was assessed against several cancer cell lines belonging to nine different panels as per National Cancer Institute (NCI US) protocol. 4-Chloro-2-((5-(3,4,5-trimethoxyphenyl)-1,3,4-oxadiazol-2-yl)amino)phenol (6h) demonstrated significant anticancer activity against SNB-19 (PGI = 65.12), NCI-H460 (PGI = 55.61), and SNB-75 (PGI = 54.68) at 10 µM. The compounds were subjected to molecular docking studies against the active site of the tubulin-combretastatin A4 complex (PDB ID: 5LYJ); they displayed efficient binding and ligand 4h (with docking score = -8.030 kcal/mol) lay within the hydrophobic cavity surrounded by important residues Leu252, Ala250, Leu248, Leu242, Cys241, Val238, Ile318, Ala317, and Ala316. Furthermore, the antibacterial activity of some of the compounds was found to be promising. 4-Chloro-2-((5-(4-nitrophenyl)-1,3,4-oxadiazol-2-yl)amino)phenol (6c) displayed the most promising antibacterial activity against both Gram-negative as well as Gram-positive bacteria with MICs of 8 µg/mL and a zone of inhibition ranging from 17.0 ± 0.40 to 17.0 ± 0.15 mm at 200 µg/mL; however, the standard drug ciprofloxacin exhibited antibacterial activity with MIC values of 4 µg/mL.

Synthesis and Biological Evaluation of Octahydroquinazolinones as Phospholipase A2, and Protease Inhibitors: Experimental and Theoretical Exploration.

Phospholipase A2 (PLA2) promotes inflammation via lipid mediators and releases arachidonic acid (AA), and these enzymes have been found to be elevated in a variety of diseases, including rheumatoid arthritis, sepsis, and atherosclerosis. The mobilization of AA by PLA2 and subsequent synthesis of prostaglandins are regarded as critical events in inflammation. Inflammatory processes may be treated with drugs that inhibit PLA2, thereby blocking the COX and LOX pathways in the AA cascade. To address this issue, we report herein an efficient method for the synthesis of a series of octahydroquinazolinone compounds (4a-h) in the presence of the catalyst Pd-HPW/SiO2 and their phospholipase A2, as well as protease inhibitory activities. Among eight compounds, two of them exhibited overwhelming results against PLA2 and protease. By using FT-IR, Raman, NMR, and mass spectroscopy, two novel compounds were thoroughly studied. After carefully examining the SAR of the investigated compounds against these enzymes, it was found that compounds (4a, 4b) containing both electron-donating and electron-withdrawing groups on the phenyl ring exhibited higher activity than compounds with only one of these groups. DFT studies were employed to study the electronic nature and reactivity properties of the molecules by optimizing at the BLYP/cc-pVDZ. Natural bond orbitals helped to study the various electron delocalizations in the molecules, and the frontier molecular orbitals helped with the reactivity and stability parameters. The nature and extent of the expressed biological activity of the molecule were studied using molecular docking with human non-pancreatic secretory phospholipase A2 (hnps-PLA2) (PDB ID: 1DB4) and protease K (PDB ID: 2PWB). The drug-ability of the molecule has been tested using ADMET, and pharmacodynamics data have been extracted. Both the compounds qualify for ADME properties and follow Lipinski's rule of five.

Synthesis and SAR of Potential Anti-Cancer Agents of Quinoline Analogues: A Review.

Quinoline has recently become an important heterocyclic molecule due to its numerous industrial and synthetic organic chemistry applications. Quinoline derivatives have been used in clinical trials for a variety of medical conditions that causes cancer. The present literature study is composed of recent progress (mainly from 2010 to the present) in the production of novel quinoline derivatives as potential anti-cancer agents, as well as their structure-activity relationship, which will provide insight into the development of more active quinoline hybrids in the future. The present review comprises the synthetic protocols of biologically active Quinoline analogs with their structure-activity relationship studies as anti-cancer agents, which provide depth view of work done on quinoline derivatives to the medicinal chemist for future research.

Design, Synthesis, In Vivo, and In Silico Evaluation of Benzothiazoles Bearing a 1,3,4-Oxadiazole Moiety as New Antiepileptic Agents.

In the presented manuscript, a new series of 2-[4-methoxy-3-(5-substituted phenyl-[1,3,4]oxadiazol-2-ylmethoxy)-phenyl]-benzothiazoles (6a-n) have been synthesized and studied in vivo and in silico for their anticonvulsant potential. Maximum electroshocks (MES) and subcutaneous pentylenetetrazol (scPTZ) models have been used for in vivo anticonvulsant activity. Auto Dock 4.2 software was used for in silico studies, and the targeted protein was 5IOV.sThe antidepressant activity of selected compounds (most active) was determined as a reduction in locomotor activity through an actophotometer. In vivo and In silico studies proved that among all the synthesized compounds, 6f, 6h, 6j, and 6l were the most potent with no neurotoxicity as compared to conventional drugs (phenytoin and phenobarbital). The in silico studies also indicated about different binding interactions of synthetic compounds to localize the binding receptors. The most likely mode of action for these drugs, according to the docking analysis of active compounds with various targets, is their binding to the VGCC and NMDA receptors.

Levosimendan: mechanistic insight and its diverse future aspects in cardiac care.

Inotropic agents are generally recommended to use in patients with acute decompensated heart failure (HF) with reduced ejection fraction (HFrEF) concurrent to end-organ dysfunction. However, due to certain pharmacological limitations like developing life threatening arrhythmia and tolerance, cannot be employed as much as needed. Meanwhile, Calcium ion (Ca2+) sensitisers exhibits their inotropic action by increasing the sensitivity of the cardiomyocyte to intracellular Ca2+ ion and have been reported as emerging therapeutic alternative in HF cases. Levosimendan (LEVO) is an inodilator and with its unique pharmacology justifying its use in a wide range of cardiac alterations in HF particularly in undergoing cardiac surgery. It is also reported to be better than classical inotropes in maintaining cardiac mechanical efficacy and reducing congestion in acute HF with hypotension. This review paper was designed to compile various evidence about basic pharmacology and potential clinical aspects of LEVO in cardiac surgery and other HF associated alterations. This will benefit directly to the researcher in initiating research and to fill the gaps in the area of thrust.

Recent Updates on Synthesis, Biological Activity, and Structure-activity Relationship of 1,3,4-Oxadiazole-quinoline Hybrids: A Review.

Due to their diverse applications in industrial and synthetic organic chemistry, quinoline and 1,3,4-oxadiazole have become important heterocyclic compounds. Quinoline and 1,3,4- oxadiazole compounds have been developed for various medical conditions such as anti-cancer, anti-bacterial, anti-fungal, antimalarial, antioxidants, anti-HIV, anticonvulsant, antiviral, etc. The current review includes synthetic protocols for biologically active 1,3,4-oxadiazole incorporating quinoline hybrids with their structure-activity relationship to explore work (Mainly from 2010 to 2021) based on 1,3,4-oxadiazole-quinoline hybrids to the medicinal chemist for further research in the development of the molecule.

An Efficient Synthesis of 1-(1,3-Dioxoisoindolin-2-yl)-3-aryl Urea Analogs as Anticancer and Antioxidant Agents: An Insight into Experimental and In Silico Studies.

The present investigation reports the efficient multistep synthesis of 1-(1,3-dioxoisoindolin-2-yl)-3-aryl urea analogs (7a-f) in good yields. All the 1-(1,3-dioxoisoindolin-2-yl)-3-aryl urea analogs (7a-f) were characterized by spectroscopic techniques. Five among the six compounds were tested against 56 cancer cell lines at 10 µM as per the standard protocol. 1-(4-Bromophenyl)-3-(1,3-dioxoisoindolin-2-yl)urea (7c) exhibited moderate but significant anticancer activity against EKVX, CAKI-1, UACC-62, MCF7, LOX IMVI, and ACHN with percentage growth inhibitions (PGIs) of 75.46, 78.52, 80.81, 83.48, 84.52, and 89.61, respectively. Compound 7c was found to exhibit better anticancer activity than thalidomide against non-small cell lung, CNS, melanoma, renal, prostate, and breast cancer cell lines. It was also found to exhibit superior anticancer activity against melanoma cancer compared to imatinib. Among the tested compounds, the 4-bromosubstitution (7c) on the phenyl ring demonstrated good anticancer activity. Docking scores ranging from -6.363 to -7.565 kcal/mol were observed in the docking studies against the molecular target EGFR. The ligand 7c displayed an efficient binding against the EGFR with a docking score of -7.558 kcal/mol and displayed an H-bond interaction with Lys745 and the carbonyl functional group. Compound 7c demonstrated a moderate inhibition of EGFR with an IC50 of 42.91 ± 0.80 nM, in comparison to erlotinib (IC50 = 26.85 ± 0.72 nM), the standard drug. The antioxidant potential was also calculated for the compounds (7a-f), which exhibited good to low activity. 1-(2-Methoxyphenyl)-3-(1,3-dioxoisoindolin-2-yl)urea (7f) and 1-(4-Methoxyphenyl)-3-(1,3-dioxoisoindolin-2-yl)urea (7d) demonstrated significant antioxidant activity with IC50 values of 15.99 ± 0.10 and 16.05 ± 0.15 µM, respectively. The 2- and 4-methoxysubstitutions on the N-phenyl ring showed good antioxidant activity among the series of compounds (7a-f). An in silico ADMET prediction studies showed the compounds' adherence to Lipinski's rule of five: they were free from toxicities, including mutagenicity, cytotoxicity, and immunotoxicity, but not for hepatotoxicity. The toxicity prediction demonstrated LD50 values between 1000 and 5000 mg/Kg, putting the compounds either in class IV or class V toxicity classes. Our findings might create opportunities for more advancements in cancer therapeutics.

Molecular Target Interactions of Quinoline Derivatives as Anticancer Agents: A Review.

One of the leading causes of death worldwide is cancer, which poses substantial risks to both society and an individual's life. Cancer therapy is still challenging, despite developments in the field and continued research into cancer prevention. The search for novel anticancer active agents with a broader cytotoxicity range is therefore continuously ongoing. The benzene ring gets fused to a pyridine ring at two carbon atoms close to one another to form the double ring structure of the heterocyclic aromatic nitrogen molecule known as quinoline (1-azanaphthalene). Quinoline derivatives contain a wide range of pharmacological activities, including antitubercular, antifungal, antibacterial, and antimalarial properties. Quinoline derivatives have also been shown to have anticancer properties. There are many quinoline derivatives widely available as anticancer drugs that act via a variety of mechanisms on various molecular targets, such as inhibition of topoisomerase, inhibition of tyrosine kinases, inhibition of heat shock protein 90 (Hsp90), inhibition of histone deacetylases (HDACs), inhibition of cell cycle arrest and apoptosis, and inhibition of tubulin polymerization.

Pyrazoline Containing Compounds as Therapeutic Targets for Neurodegenerative Disorders.

Pyrazolines are a significant class of heterocyclic compounds with essential biological activities. They are quite stable, which has inspired medicinal chemists to experiment with the ring's structure in many different ways to create a variety of pharmacological activities. The structures of numerous commercially available therapeutic agents contain a pyrazoline ring. Pyrazolines are well-known for their ability to treat neurodegenerative diseases. The neurodegenerative diseases that affect huge populations globally include Alzheimer's disease (AD), Parkinson's disease (PD), and psychiatric disorders. The neuroprotective properties of pyrazolines published since 2003 are covered in the current review. Structure-activity relationships (SARs), molecular docking simulation, anticholinesterase (anti-AChE), and monoamine oxidase (MAO A/B) inhibitory actions are all covered in this article. Pyrazolines were discovered to have beneficial effects in the management of AD and were revealed to be inhibitors of acetylcholine esterase (AChE) and beta-amyloid (Aß) plaques. They were discovered to be efficient against PD and also targeted MAO B and COMT. It was discovered that the pyrazolines block MAO A to treat psychiatric diseases. Pyrazolines are significant heteroaromatic scaffolds with a variety of biological functions. They were discovered to be remarkably stable and serve as an indispensable anchor for the development of new drugs. By blocking AChE and MAOs, they may be used to treat neurodegenerative diseases. The discussion outlined here is an essential and helpful resource for medicinal chemists who are investigating and applying pyrazolines in neurodegenerative research initiatives as well as to expedite future research programs on neurodegenerative disorders.

Synthesis, DFT Analyses, Antiproliferative Activity, and Molecular Docking Studies of Curcumin Analogues.

With 19.3 million new cases and almost 10 million deaths in 2020, cancer has become a leading cause of death today. Curcumin and its analogues were found to have promising anticancer activity. Inspired by curcumin's promising anticancer activity, we prepared three semi-synthetic analogues by chemically modifying the diketone function of curcumin to its pyrazole counterpart. The curcumin analogues (3a−c) were synthesized by two different methods, followed by their DFT analyses to study the HOMO/LUMO configuration to access the stability of compounds (∆E = 3.55 to 3.35 eV). The curcumin analogues (3a−c) were tested for antiproliferative activity against a total of five dozen cancer cell lines in a single (10 µM) and five dose (0.001 to 100 µM) assays. 3,5-Bis(4-hydroxy-3-methoxystyryl)-1H-pyrazole-1-yl-(phenoxy)ethanone (3b) and 3,5-bis(4-hydroxy-3-methoxystyryl)-1H-pyrazole-1-yl-(2,4-dichlorophenoxy)ethanone (3c) demonstrated the most promising antiproliferative activity against the cancer cell lines with growth inhibitions of 92.41% and 87.28%, respectively, in a high single dose of 10 µM and exhibited good antiproliferative activity (%GIs > 68%) against 54 out of 56 cancer cell lines and 54 out of 60 cell lines, respectively. The compound 3b and 3c demonstrated the most potent antiproliferative activity in a 5-dose assay with GI50 values ranging between 0.281 and 5.59 µM and 0.39 and 0.196 and 3.07 µM, respectively. The compound 3b demonstrated moderate selectivity against a leukemia panel with a selectivity ratio of 4.59. The HOMO-LUMO energy-gap (∆E) of the compounds in the order of 3a > 3b > 3c, was found to be in harmony with the anticancer activity in the order of 3c ≥ 3b > 3a. Following that, all of the curcumin analogues were molecular docked against EGFR, one of the most appealing targets for antiproliferative activity. In a molecular docking simulation, the ligand 3b exhibited three different types of interactions: H-bond, π-π-stacking and π-cationic. The ligand 3b displayed three H-bonds with the residues Met793 (with methoxy group), Lys875 (with phenolic group) and Asp855 (with methoxy group). The π-π-stacking interaction was observed between the phenyl (of phenoxy) and the residue Phe997, while π-cationic interaction was displayed between the phenyl (of curcumin) and the residue Arg841. Similarly, the ligand 3c displayed five H-bonds with the residue Met793 (with methoxy and phenolic groups), Lys845 (methoxy group), Cys797 (phenoxy oxygen), and Asp855 (phenolic group), as well as a halogen bond with residue Cys797 (chloro group). Furthermore, all the compound 3a−c demonstrated significant binding affinity (−6.003 to −7.957 kcal/mol) against the active site of EGFR. The curcumin analogues described in the current work might offer beneficial therapeutic intervention for the treatment and prevention of cancer. Future anticancer drug discovery programs can be expedited by further modifying these analogues to create new compounds with powerful anticancer potentials.

Chemical Modification of Curcumin into Its Semi-Synthetic Analogs Bearing Pyrimidinone Moiety as Anticancer Agents.

Natural products (NPs) continue to provide a structural template for the design of novel therapeutic agents and expedite the drug discovery process. The majority of FDA-approved pharmaceuticals used in medical practice can be traced back to natural sources, and NPs play a significant role in drug development. Curcumin, one of the most well-studied chemicals among the NPs, is currently the subject of intense investigation for its biological effects, including the prevention and treatment of cancer. Cancer has overtaken all other causes of death in the world today, with 19.3 million new cases and nearly 10 million deaths predicted in 2020. In the present investigation, we reported the synthesis of three semi-synthetic analogues of curcumin-bearing pyrimidinone moiety by the chemical modification of the diketone function of curcumin followed by their characterization by analytical techniques including infrared (IR), nuclear magnetic resonance (NMR), and mass spectral data. According to the National Cancer Institute (NCI US) methodology, the curcumin analogues (C1-C3) were tested for their anticancer efficacy against 59 cancer cell lines in a single dose assay. 1-(2,6-Dichlorophenyl)-4,6-bis((E)-4-hydroxy-3-methoxystyryl)pyrimidin-2(1H)-one (C2) demonstrated the most promising anticancer activity with mean percent growth inhibition (%GIs) of 68.22 in single dose assay at 10 µM. The compound exhibited >68 %GIs against 31 out of 59 cancer cell lines and was found to be highly active against all leukemia and breast cancer cell lines. The compound C2 showed a lethal effect on HT29 (colon cancer) with %GI of 130.44, while 99.44 %GI was observed against RPMI-8226 (Leukemia). The compound C2 displayed better anticancer activity against the panels of CNS, melanoma, ovarian, prostate, and breast cancer cell lines than curcumin and other anti-EGFR agents gefitinib and imatinib in single dose assay. The compound C2 also demonstrated potent anticancer activity in a 5-dose assay (0.001 to 100 µM) with GI50 values ranging from 1.31 to 4.68 µM; however, it was found to be non-selective with SR values ranging from 0.73 to 1.35. The GI50 values of compound C2 were found to be better than that of the curcumin against all nine panels of cancer cell lines. All of the curcumin analogues were subsequently investigated for molecular docking simulation against EGFR, one of the most attractive targets for antiproliferative action. In molecular docking studies, all the ligands were found to accommodate the active site of EGFR and the binding affinity of ligand C2 was found to be −5.086 kcal/mol. The ligand C2 exhibited three different types of interactions: H-bond (Thr790 and Thr854), π-cationic (Arg841), and aromatic H-bond (Asn842). The curcumin analogues reported in the current investigation may provide valuable therapeutic intervention for the prevention and treatment of cancer and accelerate anticancer drug discovery programs in the future.

An Insight into the Structural Requirements and Pharmacophore Identification of Carbonic Anhydrase Inhibitors to Combat Oxidative Stress at High Altitudes: An In-Silico Approach.

Carbonic anhydrases (CA) inhibitory action could be linked to the treatment of a number of ailments, including cancer, osteoporosis, glaucoma, and several neurological problems. For the development of effective CA inhibitors, a variety of heterocyclic rings have been investigated. Furthermore, at high altitudes, oxygen pressure drops, resulting in the formation of reactive oxygen and nitrogen species, and CA inhibitors having role in combating this oxidative stress. Acetazolamide contains thiadiazole ring, which has aroused researchers' interest because of its CA inhibitory action. In the present study, we used a number of drug design tools, such as pharmacophore modeling, 3D QSAR, docking, and virtual screening on twenty-seven 1,3,4-thiadiazole derivatives that have been described as potential CA inhibitors in the literature. An atom-based 3D-QSAR analysis was carried out to determine the contribution of individual atoms to model generation, while a pharmacophore mapping investigation was carried out to find the common unique pharmacophoric properties required for biological activity. The coefficient of determination for both the training and test sets were statistically significant in the generated model. The best QSAR model was chosen based on the values of R2 (0.8757) and Q2 (0.7888). A molecular docking study was also conducted against the most potent analogue 4m, which has the highest SP docking score (-5.217) (PDB ID: 6g3v). The virtual screening revealed a number of promising compounds. The screened compound ZINC77699643 interacted with the amino acid residues, Pro201 and Thr199, in the virtual screening study (PDB ID: 6g3v). These interactions demonstrated the significance of the CA inhibitory activity of the compound. Furthermore, ADME study revealed useful information regarding compound's drug-like properties. Therefore, the findings of the present investigation could aid in the development of more potent CA inhibitors, which could benefit the treatment of oxidative stress at high altitudes.

Toward the Discovery of a Novel Class of Leads for High Altitude Disorders by Virtual Screening and Molecular Dynamics Approaches Targeting Carbonic Anhydrase.

For decades, carbonic anhydrase (CA) inhibitors, most notably the acetazolamide-bearing 1,3,4-thiadiazole moiety, have been exploited at high altitudes to alleviate acute mountain sickness, a syndrome of symptomatic sensitivity to the altitude characterized by nausea, lethargy, headache, anorexia, and inadequate sleep. Therefore, inhibition of CA may be a promising therapeutic strategy for high-altitude disorders. In this study, co-crystallized inhibitors with 1,3,4-thiadiazole, 1,3-benzothiazole, and 1,2,5-oxadiazole scaffolds were employed for pharmacophore-based virtual screening of the ZINC database, followed by molecular docking and molecular dynamics simulation studies against CA to find possible ligands that may emerge as promising inhibitors. Compared to the co-crystal ligands of PDB-1YDB, 6BCC, and 6IC2, ZINC12336992, ZINC24751284, and ZINC58324738 had the highest docking scores of -9.0, -9.0, and -8.9 kcal/mol, respectively. A molecular dynamics (MD) simulation analysis of 100 ns was conducted to verify the interactions of the top-scoring molecules with CA. The system's backbone revealed minor fluctuations, indicating that the CA-ligand complex was stable during the simulation period. Simulated trajectories were used for the MM-GBSA analysis, showing free binding energies of -16.00 ± 0.19, -21.04 ± 0.17, and -19.70 ± 0.18 kcal/mol, respectively. In addition, study of the frontier molecular orbitals of these compounds by DFT-based optimization at the level of B3LYP and the 6-311G(d,p) basis set showed negative values of the HOMO and LUMO, indicating that the ligands are energetically stable, which is essential for forming a stable ligand-protein complex. These molecules may prove to be a promising therapy for high-altitude disorders, necessitating further investigations.

Transdermal Nutraceuticals Delivery System for CNS Disease.

Herbal medicines are being used by humans since the oldest civilizations and have been an integral part of traditional and alternative medicines. In recent times, pharmaceutical and biomedical scientists are taking interest in developing nutraceutical-based medicines to overcome the side effects and adverse drug reactions caused by allopathic medicines. Nutraceuticals have started occupying the global market. Nutraceuticals have gained widespread acceptance due to their efficacy in treating difficult to treat diseases, low toxicity, low cost, easy accessibility, etc. Safety and efficacy are other important factors in the commercialization process of nutraceuticals. Different novel advanced drug delivery systems have been constantly studied to improve the efficacy and bioavailability of medicines obtained from herbal sources. The transdermal drug delivery system provides a potent alternative to the conventional method of using nutraceuticals. The development of transdermal system-based nutraceuticals could provide the advantage of enhanced bioavailability, improved solubility, bypass of the first-pass metabolism, and targeted delivery of drugs in brain-related disorders. It additionally provides the advantage of being non-invasive. This article reviews the potential effects of various nutraceuticals in brain-related disorders as well as trends in transdermal nano-systems to deliver such nutraceuticals. We have also focused on advantages, applications as well as recent United States-based patents which emphasize emerging interest towards transdermal nutraceuticals in brain disorders.

Green Synthesis of Oxoquinoline-1(2H)-Carboxamide as Antiproliferative and Antioxidant Agents: An Experimental and In-Silico Approach to High Altitude Related Disorders.

At high altitudes, drops in oxygen concentration result in the creation of reactive oxygen and nitrogen species (RONS), which cause a variety of health concerns. We addressed these health concerns and reported the synthesis, characterization, and biological activities of a series of 10 oxoquinolines. N-Aryl-7-hydroxy-4-methyl-2-oxoquinoline-1(2H)carboxamides (5a-j) were accessed in two steps under ultrasonicated irradiation, as per the reported method. The anticancer activity was tested at 10 µM against a total of 5 dozen cancer cell lines obtained from nine distinct panels, as per the National Cancer Institute (NCI US) protocol. The compounds 5a (TK-10 (renal cancer); %GI = 82.90) and 5j (CCRF-CEM (Leukemia); %GI = 58.61) showed the most promising anticancer activity. Compound 5a also demonstrated promising DPPH free radical scavenging activity with an IC50 value of 14.16 ± 0.42 µM. The epidermal growth factor receptor (EGFR) and carbonic anhydrase (CA), two prospective cancer inhibitor targets, were used in the molecular docking studies. Molecular docking studies of ligand 5a (docking score = -8.839) against the active site of EGFR revealed two H-bond interactions with the residues Asp855 and Thr854, whereas ligand 5a (docking = -5.337) interacted with three H-bond with the residues Gln92, Gln67, and Thr200 against the active site CA. The reported compounds exhibited significant anticancer and antioxidant activities, as well as displayed significant inhibition against cancer targets, EGFR and CA, in the molecular docking studies. The current discovery may aid in the development of novel compounds for the treatment of cancer and oxidative stress, and other high altitude-related disorders.

Machine Learning in Drug Discovery: A Review.

This review provides the feasible literature on drug discovery through ML tools and techniques that are enforced in every phase of drug development to accelerate the research process and deduce the risk and expenditure in clinical trials. Machine learning techniques improve the decision-making in pharmaceutical data across various applications like QSAR analysis, hit discoveries, de novo drug architectures to retrieve accurate outcomes. Target validation, prognostic biomarkers, digital pathology are considered under problem statements in this review. ML challenges must be applicable for the main cause of inadequacy in interpretability outcomes that may restrict the applications in drug discovery. In clinical trials, absolute and methodological data must be generated to tackle many puzzles in validating ML techniques, improving decision-making, promoting awareness in ML approaches, and deducing risk failures in drug discovery.