FDA-approved drugs containing dimethylamine pharmacophore: a review of the last 50 years.

Dimethylamine (DMA) derivatives represent a promising class of compounds with significant potential in the field of medicinal chemistry. DMA derivatives exhibit a diverse range of pharmacological activities, including antimicrobial, antihistaminic, anticancer, and analgesic properties. Their unique chemical structure allows for the modulation of various biological targets, making them valuable candidates for the treatment of numerous diseases. Synthetic strategies for the preparation of DMA derivatives vary depending on the desired biological activity and target molecule. Common synthetic routes involve the modification of the DMA scaffold through functional group manipulation, scaffold hopping, or combinatorial chemistry approaches. Therapeutically, DMA derivatives have shown promise in the treatment of infectious diseases, especially bacterial infections. Additionally, by focusing on particular biochemical pathways involved in tumor growth and metastasis, DMA-based drugs have shown anticancer activity. In addition to their direct pharmacological effects, DMA derivatives can serve as valuable tools in drug delivery systems, prodrug design, and molecular imaging techniques, enhancing their utility in medicinal chemistry research. Overall, DMA derivatives represent a versatile class of compounds with immense potential in medicinal chemistry. Further research and development efforts are warranted to explore their full therapeutic capabilities and optimize their clinical utility in the treatment of various diseases. This article outlines the pharmacological properties, synthetic strategies, and therapeutic applications of DMA derivatives of FDA approved drugs, highlighting their importance in drug discovery and development.

In Silico Molecular Docking and Molecular Dynamics Analysis of Antimicrobial Triazole Derivatives: Insights from Synthesis, Computational and In Vitro Studies.

INTRODUCTION: In the ongoing fight against bacterial resistance to antibiotics, this study focuses on synthesizing and evaluating 1,2,4-triazole derivatives to explore their potential as new antibacterial agents. 1,2,4-Triazole compounds are promising drug candidates with a wide range of therapeutic effects, including pain relief, antiseptic, antimicrobial, antioxidant, antiurease, anti-inflammatory, diuretic, anticancer, anticonvulsant, antidiabetic, and antimigraine properties. METHOD: The structures of all the synthesized compounds were identified using their physicochemical properties and spectral techniques, such as IR and NMR. These compounds were then evaluated in molecular docking studies against antimicrobial activity in vitro and further supported by molecular dynamics studies. RESULT: Compound 7, featuring a 6-chloro group on the phenyl ring, emerged as the most effective against Gram-positive S. aureus compared to the standard antibiotic ciprofloxacin. Docking studies revealed high and comparable affinities for all ten ligands, with compounds 4 and 6 showing the best-docked activity against Penicillin Acylase mutants. Further, compounds 6 and 10 displayed significant affinity against D-alanine-D-alanine ligase (DDL) from Yersinia pestis during 100 ns MD simulation. CONCLUSION: Notably, compound 7 demonstrated the highest binding score to the 5C1P protein, suggesting its potential as a lead molecule for the development of potent and safer antimicrobial agents. This research contributes valuable insights into addressing the escalating challenge of bacterial resistance.

Elucidating molecular mechanism and chemical space of chalcones through biological networks and machine learning approaches.

We developed a bio-cheminformatics method, exploring disease inhibition mechanisms using machine learning-enhanced quantitative structure-activity relationship (ML-QSAR) models and knowledge-driven neural networks. ML-QSAR models were developed using molecular fingerprint descriptors and the Random Forest algorithm to explore the chemical spaces of Chalcones inhibitors against diverse disease properties, including antifungal, anti-inflammatory, anticancer, antimicrobial, and antiviral effects. We generated and validated robust machine learning-based bioactivity prediction models (https://github.com/RatulChemoinformatics/QSAR) for the top genes. These models underwent ROC and applicability domain analysis, followed by molecular docking studies to elucidate the molecular mechanisms of the molecules. Through comprehensive neural network analysis, crucial genes such as AKT1, HSP90AA1, SRC, and STAT3 were identified. The PubChem fingerprint-based model revealed key descriptors: PubchemFP521 for AKT1, PubchemFP180 for SRC, PubchemFP633 for HSP90AA1, and PubchemFP145 and PubchemFP338 for STAT3, consistently contributing to bioactivity across targets. Notably, chalcone derivatives demonstrated significant bioactivity against target genes, with compound RA1 displaying a predictive pIC50 value of 5.76 against HSP90AA1 and strong binding affinities across other targets. Compounds RA5 to RA7 also exhibited high binding affinity scores comparable to or exceeding existing drugs. These findings emphasize the importance of knowledge-based neural network-based research for developing effective drugs against diverse disease properties. These interactions warrant further in vitro and in vivo investigations to elucidate their potential in rational drug design. The presented models provide valuable insights for inhibitor design and hold promise for drug development. Future research will prioritize investigating these molecules for mycobacterium tuberculosis, enhancing the comprehension of effectiveness in addressing infectious diseases.

Isatin-tethered halogen-containing acylhydrazone derivatives as monoamine oxidase inhibitor with neuroprotective effect.

Sixteen isatin-based hydrazone derivatives (IS1-IS16) were synthesized and assessed for their ability to inhibit monoamine oxidases (MAOs). All the molecules showed improved inhibitory MAO-B activity compared to MAO-A. Compound IS7 most potently inhibited MAO-B with an IC50 value of 0.082 µM, followed by IS13 and IS6 (IC50 = 0.104 and 0.124 µM, respectively). Compound IS15 most potently inhibited MAO-A with an IC50 value of 1.852 µM, followed by IS3 (IC50 = 2.385 µM). Compound IS6 had the highest selectivity index (SI) value of 263.80, followed by IS7 and IS13 (233.85 and 212.57, respectively). In the kinetic study, the Ki values of IS6, IS7, and IS13 for MAO-B were 0.068 ± 0.022, 0.044 ± 0.002, and 0.061 ± 0.001 µM, respectively, and that of IS15 for MAO-A was 1.004 ± 0.171 µM, and the compounds were reversible-type inhibitors. The lead compounds were central nervous system (CNS) permeable, as per parallel artificial membrane permeability assay (PAMPA) test results. The lead compounds were examined for their cytotoxicity and potential neuroprotective benefits in hazardous lipopolysaccharide (LPS)-exposed SH-SY5Y neuroblastoma cells. Pre-treatment with lead compounds enhanced anti-oxidant levels (SOD, CAT, GSH, and GPx) and decreased ROS and pro-inflammatory cytokine (IL-6, TNF-alpha, and NF-kB) production in LPS-intoxicated SH-SY5Y cells. To confirm the promising effects of the compound, molecular docking, dynamics, and MM-GBSA binding energy were used to examine the molecular basis of the IS7-MAO-B interaction. Our findings indicate that lead compounds are potential therapeutic agents to treat neurological illnesses, such as Parkinson's disease.

Isatin-based benzyloxybenzene derivatives as monoamine oxidase inhibitors with neuroprotective effect targeting neurogenerative disease treatment.

Eighteen isatin-based benzyloxybenzaldehyde derivatives from three subseries, ISB, ISFB, and ISBB, were synthesized and their ability to inhibit monoamine oxidase (MAO) was evaluated. The inhibitory activity of all synthesized compounds was found to be more profound against MAO-B than MAO-A. Compound ISB1 most potently inhibited MAO-B with an IC50 of 0.124 ± 0.007 µM, ensued by ISFB1 (IC50 = 0.135 ± 0.002 µM). Compound ISFB1 most potently inhibited MAO-A with an IC50 of 0.678 ± 0.006 µM, ensued by ISBB3 (IC50 = 0.731 ± 0.028 µM), and had the highest selectivity index (SI) value (55.03). The three sub-parental compounds, ISB1, ISFB1, and ISBB1, had higher MAO-B inhibition than the other derivatives, indicating that the substitutions of the 5-H in the A-ring of isatin diminished the inhibition of MAO-A and MAO-B. Among these, ISB1 (para-benzyloxy group in the B-ring) displayed more significant MAO-B inhibition when compared to ISBB1 (meta-benzyloxy group in the B-ring). ISB1 and ISFB1 were identified to be competitive and reversible MAO-B inhibitors, having Ki values of 0.055 ± 0.010, and 0.069 ± 0.025 µM, respectively. Furthermore, in the parallel artificial membrane penetration assay, ISB1 and ISFB1 traversed the blood-brain barrier in the in vitro condition. Additionally, the current study found that ISB1 decreased rotenone-induced cell death in SH-SY5Y neuroblastoma cells. In docking and simulation studies, the hydrogen bonding formed by the imino nitrogen in ISB1 and the pi-pi stacking interaction of the phenyl ring in isatin significantly aided in the protein-ligand complex's stability, effectively inhibiting MAO-B. According to these observations, the MAO-B inhibitors ISB1 and ISFB1 were potent, selective, and reversible, making them conceivable therapies for neurological diseases.

Piperidine: A Versatile Heterocyclic Ring for Developing Monoamine Oxidase Inhibitors.

The monoamine oxidase enzyme (MAO), which is bound on the membrane of mitochondria, catalyzes the oxidative deamination of endogenous and exogenous monoamines, including monoamine neurotransmitters such as serotonin, adrenaline, and dopamine. These enzymes have been proven to play a significant role in neurodegeneration; thus, they have recently been researched as prospective therapeutic targets for neurodegenerative illness treatment and management. MAO inhibitors have already been marketed as neurodegeneration illness treatments despite their substantial side effects. Hence, researchers are concentrating on developing novel molecules with selective and reversible inhibitory properties. Piperine, which is a phytochemical component present in black pepper, has been established as a potent MAO inhibitor. Piperine encompasses a piperidine nucleus with antibacterial, anti-inflammatory, antihypertensive, anticonvulsant, antimalarial, antiviral, and anticancer properties. The current Review focuses on the structural changes and structure-activity relationships of piperidine derivatives as MAO inhibitors.

A computational investigation of thymidylate synthase inhibitors through a combined approach of 3D-QSAR and pharmacophore modelling.

Thymidylate synthase (TS) is a crucial target of cancer drug discovery and is mainly involved in the De novo synthesis of the DNA precursor thymine. In the present study, to generate reliable models and identify a few promising molecules, we combined QSAR modelling with the pharmacophore hypothesis-generating technique. Input molecules were clustered on their similarity, and a cluster of 74 molecules with a pyrimidine moiety was chosen as the set for 3D-QSAR and pharmacophore modelling. Atom-based and field-based 3D-QSAR models were generated and statistically validated with R2 > 0.90 and Q2 > 0.75. The common pharmacophore hypothesis(CPH) generation identified the best six-point model ADHRRR. Using these best models, a library of FDA-approved drugs was screened for activity and filtered via molecular docking, ADME profiling, and molecular dynamics simulations. The top ten promising TS-inhibiting candidates were identified, and their chemical features profitable for TS inhibitors were explored.Communicated by Ramaswamy H. Sarma.

Assembling a Cinnamyl Pharmacophore in the C3-Position of Substituted Isatins via Microwave-Assisted Synthesis: Development of a New Class of Monoamine Oxidase-B Inhibitors for the Treatment of Parkinson's Disease.

Monoamine oxidase (MAO, EC 1.4.3.4) is responsible for the oxidative breakdown of both endogenous and exogenous amines and exists in MAO-A and MAO-B isomers. Eighteen indole-based phenylallylidene derivatives were synthesized via nucleophilic addition reactions comprising three sub-series, IHC, IHMC, and IHNC, and were developed and examined for their ability to inhibit MAO. Among them, compound IHC3 showed a strong MAO-B inhibitory effect with an IC50 (half-maximal inhibitory concentration) value of 1.672 µM, followed by IHC2 (IC50 = 16.934 µM). Additionally, IHC3 showed the highest selectivity index (SI) value of >23.92. The effectiveness of IHC3 was lower than the reference pargyline (0.14 µM); however, the SI value was higher than pargyline (17.16). Structurally, the IHC (-H in the B-ring) sub-series exhibited relatively stronger MAO-B inhibition than the others. In the IHC series, IHC3 (-F in the A-ring) exhibited stronger MAO-B suppression than the other substituted derivatives in the order -F > -Br > -Cl > -OCH3, -CH3, and -H at the 2-position in the A-ring. In the reversibility and enzyme kinetics experiments, IHC3 was a reversible inhibitor with a Ki value of 0.51 ± 0.15 µM for MAO-B. Further, it was observed that IHC3 greatly decreased the cell death caused by rotenone in SH-SY5Y neuroblastoma cells. A molecular docking study of the lead molecule was also performed to determine hypothetical interactions in the enzyme-binding cavity. These findings suggest that IHC3 is a strong, specific, and reversible MAO-B inhibitor that can be used to treat neurological diseases.

Decoding Immune Signature to Detect the Risk for Early-Stage HCC Recurrence.

Hepatocellular carcinoma (HCC) is often recognized as an inflammation-linked cancer, which possesses an immunosuppressive tumor microenvironment. Curative treatments such as surgical resection, liver transplantation, and percutaneous ablation are mainly applicable in the early stage and demonstrate significant improvement of survival rate in most patients. However, 70-80% of patients report HCC recurrence within 5 years of curative treatment, representing an important clinical issue. However, there is no effective recurrence marker after surgical and locoregional therapies, thus, tumor size, number, and histological features such as cancer cell differentiation are often considered as risk factors for HCC recurrence. Host immunity plays a critical role in regulating carcinogenesis, and the immune microenvironment characterized by its composition, functional status, and density undergoes significant alterations in each stage of cancer progression. Recent studies reported that analysis of immune contexture could yield valuable information regarding the treatment response, prognosis and recurrence. This review emphasizes the prognostic value of tumors associated with immune factors in HCC recurrence after curative treatment. In particular, we review the immune landscape and immunological factors contributing to early-stage HCC recurrence, and discuss the immunotherapeutic interventions to prevent tumor recurrence following curative treatments.

Urachal carcinoma: The journey so far and the road ahead.

Urachal carcinoma, a rare cancer arising from urachus, accounts for about 1% of bladder cancer. The diagnosis at stage I shows about 63% 5-year survival whereas only 8% of the patients at stage IV shows a 5-year survival. Above 90% of urachal carcinomas are adenocarcinomas and most of the urachal carcinoma cases are invasive, showing a high resemblance to adenocarcinoma of various origins, making it hard for a conclusive diagnosis. Even though inconclusive, immunohistochemistry can play a significant role in identifying urachal carcinoma. Most cases show the biomarkers CK20 and CDX2, whereas CK7 and ß-catenin are expressed at a lesser frequency. Due to the few cases available, there is a lack of evidence regarding specific markers differentiating urachal carcinoma from colorectal or primary bladder adenocarcinomas. In addition to immunohistochemistry, genomic characterization is emerging to play a role in the classification and treatment of the disease. Urachal carcinoma has been reported to have a molecular level similarity with colorectal malignancies regarding certain gene expressions. The TP53 mutations inactivating the tumor suppressor can probably be explored as a possible target in treating urachal carcinoma. Additionally, certain targets identified in gastric and breast cancer along with anti-HER2 treatment strategies can be explored. Immuno-oncology utilizes immune checkpoint inhibitors for the treatment of MSI-H tumors whereas a combination of tyrosine kinase inhibitors along with immune checkpoint inhibitors are being studied to treat MSI stable tumors. The article is an in-depth overview of urachal carcinoma addressing the current landscape with an emphasis on the future scenario.

Decoding the Mechanism of Drugs of Heterocyclic Nature against Hepatocellular Carcinoma.

OBJECTIVES: Hepatocellular carcinoma (HCC) is the sixth most common type of cancer and accounts for ~90% of cases, with an approximated incidence of >1 million cases by 2025. Currently, the backbone of HCC therapy is the oral multi-kinase inhibitor, Sorafenib, which consists of a Pyridine heterocycle ring system. This review highlights the introspective characteristics of seven anticancer drugs of heterocyclic nature against HCC along with their structural activity relationships and molecular targets. METHODS: Literature collection was performed using PubMed, Google Scholar, SCOPUS, and Cross ref. Additional information was taken from the official website of the FDA and GLOBOCAN. Key findings/ Results: Based on the available literature, approved heterocyclic compounds show promising results against HCC, including Sorafenib (Pyridine), Regorafenib (Pyridine), Lenvatinib (Quinoline), Cabozantinib (Quinoline), Gemcitabine (Pyrimidine), 5-Fluorouracil (Pyrimidine)and Capecitabine (Pyrimidine), their mechanism of action and key aspects regarding its structural activity were included in the review. CONCLUSION: Heterocyclic compounds represent almost two-thirds of the novel drugs approved by FDA between 2010 and 2020 against Cancer. This review summarizes the clinical relevance, mechanism of action, structural activity relationship, and challenges of the seven available anticancer drugs with heterocyclic ring systems against HCC.

Effects of radiation exposure on brain health: a state of the art and new challenges.

Good brain health refers to a condition in which a person may fully realize their talents and improve their psychological, emotional, cognitive, and behavioral functioning to cope with life's challenges. Various causes of CNS diseases are now being investigated. Radiation is one of the factors that affects the brain and causes a variety of problems. The emission or transmission of energy in the form of waves or particles via space or a material medium is known as radiation. Particle beams and electromagnetic waves are two types of ionizing radiation that have the potential to ionize atoms in a material (separating them into positively charged ions and negatively charged electrons). Radiation to the CNS can induce delayed puberty, which can lead to hyperprolactinemia, and the hypothalamic-pituitary axis can lead to gonadotropin deficit if the hypothalamic-pituitary axis is involved in the radiation field. Ionizing radiation is the most common kind of radiation. Here, we focus on the different effects of radiation on brain health. In this article, we will look at a variety of CNS diseases and how radiation affects each one, as well as how it affects the brain's numerous processes.

Effect of Hydroaloholic Extract of Rotula Aquatica Lour on Gentamicin-Induced Nephrotoxicity in Wistar Albino Rats: An In Vitro and In Vivo Approach.

One-third of the world population suffer from kidney complications such as acute and chronic renal failure, renal calculi, kidney stones, Fanconi's syndrome and urethritis which doesn't have a proper effective treatment regimen. The current study explores the nephroprotective effect of herbal drug Rotula Aquatica by both In Vitro and In Vivo methods. MTT assay was applied In Vitro to evaluate the nephroprotective effect of R. aquatica leaves extract on HEK 293 cell line. The acute toxicity of the extract was evaluated as per the limit test under the protocol of OECD 423 at a concentration of 2000 mg/kg using 6 female rats. Further, an In Vivo study using the Gentamicin-instigated nephrotoxicity model was carried out for a period of 8 days. Biochemical markers of renal damage, endogenous antioxidants and histopathology were determined to assess the effect of treatment. The In Vitro study using HEK 293 cell line resulted in an EC50 value of 51.50 µg/ml for the extract in comparison to the standard drug Cytsone (12.26 µg/ml). Based on the limit test of OECD 423, doses of 200 and 400 mg/kg were chosen for the study. The results revealed a strong nephroprotective activity at 400 mg/kg in Gentamicin-induced nephrotoxicity against standard drug cystone by restoring the decrement in body weight, renal enzymatic and non-enzymatic antioxidants, creatinine and urea levels in urine and plasma. This indicated that hydroalcoholic extract of Rotula aquatica (HAERA) can prevent the Gentamicin toxicity due to the high content of antioxidant and anti-inflammatory secondary metabolites.

Exploration of the Detailed Structure-Activity Relationships of Isatin and Their Isomers As Monoamine Oxidase Inhibitors.

Monoamine oxidase (MAO) is a protein with a key function in the catabolism of neuroamines in both central and peripheral parts of the body. MAO-A and -B are two isozymes of this enzyme which have emerged to be considered as a drug target for the treatment of neurodenerative disorders such as Alzheimer's disease (AD) and Parkinson's disease (PD). Isatin is an endogenous small fragment, reversible inhibitor for MAO enzymes and is more selective for MAO-B than -A. Isatin is responsible for increasing the dopamine level in the brain by the inhibition of an MAO enzyme. The very few selective and reversible inhibitors existing for MAO proteins and the intensity of neurological diseases in humanity have opened a new door for researchers. Isatin has a polypharmacological profile in medicinal chemistry, is a reversible inhibitor for both the MAOs, and shows high selectivity potent inhibition for MAO-B. In this review, we discuss isatins and their analogues phthalide and phthalimide with structure-activity relationships (SARs), and this comprehensive information accelerates the ideas for design and development of a new class of MAO inhibitors for neurodegenerative diseases.

Biological investigation of N-methyl thiosemicarbazones as antimicrobial agents and bacterial carbonic anhydrases inhibitors.

The enormous burden of the COVID-19 pandemic in economic and healthcare terms has cast a shadow on the serious threat of antimicrobial resistance, increasing the inappropriate use of antibiotics and shifting the focus of drug discovery programmes from antibacterial and antifungal fields. Thus, there is a pressing need for new antimicrobials involving innovative modes of action (MoAs) to avoid cross-resistance rise. Thiosemicarbazones (TSCs) stand out due to their easy preparation and polypharmacological application, also in infectious diseases. Recently, we reported a small library of TSCs (1-9) that emerged for their non-cytotoxic behaviour. Inspired by their multifaceted activity, we investigated the antibacterial, antifungal, and antidermatophytal profiles of derivatives 1-9, highlighting a new promising research line. Furthermore, the ability of these compounds to inhibit selected microbial and human carbonic anhydrases (CAs) was assessed, revealing their possible involvement in the MoA and a good selectivity index for some derivatives.

A Medicinal Chemist's Perspective Towards Structure Activity Relationship of Heterocycle Based Anticancer Agents.

AIM: This paper aims to describe the structure activity relationship of heterocyclic derivatives with multi-targeted anticancer activity. OBJECTIVES: With the following goals in mind, this review tries to describe significant recent advances in the medicinal chemistry of heterocycle-based compounds: (1) To shed light on recent literature focused on heterocyclic derivatives' anticancer potential; (2) To discuss recent advances in the medicinal chemistry of heterocyclic derivatives, as well as their biological implications for cancer eradication; (3) To summarise the comprehensive correlation of structure activity relationship (SAR) with pharmacological outcomes in cancer therapy. BACKGROUND: Cancer remains one of the major serious health issues in the world today. Cancer is a complex disease in which improperly altered cells proliferate at an uncontrolled, rapid, and severe rate. Variables such as poor dietary habits, high stress, age, and smoking, can all contribute to the development of cancer. Cancer can affect almost any organ or tissue, although the brain, breast, liver, and colon are the most frequently affected organs. For several years, surgical operations and irradiation have been in use along with chemotherapy as a primary treatment of cancer, but still, effective treatment of cancer remains a huge challenge. Chemotherapy is now considered one of the most effective strategies to eradicate cancer, although it has been shown to have a number of cytotoxic and unfavourable effects on normal cells. Despite all of these cancer treatments, there are several other targets for anticancer drugs. Cancer can be effectively eradicated by focusing on these targets, including cell-specific and receptor-specific targets such as tyrosine kinase receptors (TKIs). Heterocyclic scaffolds also have a variety of applications in drug development and are a common moiety in the pharmaceutical, agrochemical, and textile industries. METHODS: The association between structural activity relationship data of many powerful compounds and their anticancer potential in vitro and in vivo has been studied. SAR of powerful heterocyclic compounds can also be generated using molecular docking simulations, as reported in literature. CONCLUSION: Heterocycles have a wide range of applications, from natural compounds to synthesised derivatives with powerful anticancer properties. To avoid cytotoxicity or unfavourable effects on normal mammalian cells due to a lack of selectivity towards the target site, as well as to reduce the occurrence of drug resistance, safer anticancer lead compounds with higher potency and lower cytotoxicity are needed. This review emphasizes on design and development of heterocyclic lead compounds with promising anticancer potential.

Anticipated pharmacological role of Aviptadil on COVID-19.

Vasoactive intestinal peptide (VIP) is a neuropeptide that is produced by the lymphoid cells and plays a major role in immunological functions for controlling the homeostasis of the immune system. VIP has been identified as a potent anti-inflammatory factor, in boosting both innate and adaptive immunity. Since December 2019, SARS-Cov-2 was found responsible for the disease COVID-19 which has spread worldwide. No specific therapies or 100% effective vaccines are yet available for the treatment of COVID-19. Drug repositioning may offer a strategy and several drugs have been repurposed, including lopinavir/ritonavir, remdesivir, favipiravir, and tocilizumab. This paper describes the main pharmacological properties of synthetic VIP drug (Aviptadil) which is now under clinical trials. A patented formulation of vasoactive intestinal polypeptide (VIP), named RLF-100 (Aviptadil), was developed and finally got approved for human trials by FDA in 2001 and in European medicines agency in 2005. It was awarded Orphan Drug Designation in 2001 by the US FDA for the treatment of acute respiratory distress syndrome and for the treatment of pulmonary arterial hypertension in 2005. Investigational new drug (IND) licenses for human trials of Aviptadil was guaranteed by both the US FDA and EMEA. Preliminary clinical trials seem to support Aviptadil's benefit. However, such drugs like Aviptadil in COVID-19 patients have peculiar safety profiles. Thus, adequate clinical trials are necessary for these compounds.

Navigating into the Chemical Space of Monoamine Oxidase Inhibitors by Artificial Intelligence and Cheminformatics Approach.

The monoamine oxidase (MAO) enzyme class is a prevalent target for many neurodegenerative and depressive disorders. Even though scrutinization of many promising drugs for the treatment of MAO inhibition has been carried out in recent times, a conclusive structural requirement for potent activity needs to be developed. Numerous approaches have been examined for the identification of structural features for potent MAO inhibitors (MAOIs) that mainly involve an array of computational studies, synthetic approaches, and biological evaluation. In this paper, we have analyzed ∼2200 well-known MAOIs to expand perceptions in the chemical space of MAOIs. The physicochemical properties of the MAOIs disclosed a discernible hydrophobic feature making a bunch discrete from the central nervous system (CNS) acting drugs, as exposed using the principal component analysis (PCA). The Murcko scaffold structure study revealed unfavorable and favorable scaffold structures, in both data sets, with the highest biological activity shown by the 3-phenyl-2H-chromen-2-one scaffold. This scaffold showed a polypharmacological effect. R-group disintegration and automatic structure-activity relationship (SAR) study resulted in identification of substructures responsible for the inhibitory bioactivity of the MAO-A and MAO-B enzymes. Moreover, with activity cliff analysis, significant biological activity was detected by simple molecular conversion in the chemical compound structure. In addition, we used the machine learning tool to generate a hypothesis wherein pyrazole, benzene ring, and amide containing structural functionalities can exhibit potential biological activities. This hypothesis revealed that CNS target drugs, C4155, C13390, C21265, C43862, C31524, C24810, C37100, C42075, and C43644, could be repurposed as valuable candidates for the MAO-B enzyme. For researchers, this study will bring new perceptions in the discovery and development of MAOIs and direct lead and hit optimization for the progress of small molecules beneficial for MAO-targeting associated diseases.

Recent Updates on Pyrazoline Derivatives as Promising Candidates for Neuropsychiatric and Neurodegenerative Disorders.

Pyrazolines are five-membered heterocyclic compounds containing two nitrogen atoms that represent a privileged scaffold for various bioactive compounds with diverse pharmacological activities. Chalcones and hydrazine derivatives are excellent precursors for pyrazolines, which provide easy access for fabricating the pyrazoline ring at N1, C3 and C5 positions that give rise to a wide range of pyrazoline designs. In addition, this method institutes a new asymmetric center at C5 position and extent of the conjugation between phenyl group at C3 position to N1 that could greatly enhance the physicochemical and pharmacological properties towards the target enzymes and hence they are reported to have a wide spectrum of biological activities such as anti-cancer, antiinflammatory, etc. Most importantly, they have remarkable effects on the central nervous system (CNS). Several reports show that the pyrazoline derivatives have a significant inhibitory effect towards the monoamine oxidase enzymes (MAOs), which are known to be responsible for neurodegenerative disorders. These enzymes have two isoforms, namely MAO-A and MAO-B which are, in particular, responsible for psychiatric and neurological disorders, respectively. Chalcones are generally potential and more selective inhibitors towards MAO-B isoform whereas pyrazolines derived from chalcones mostly turned into selective inhibitors of MAO-A isoform may be due to the presence of two nitrogen heteroatoms. Therefore, these two derivatives have received much attention from medicinal chemists as they could solve entire CNS-related issues; however pyrazolines have not been studied as much as chalcones. Our group already documented the importance of pyrazolines towards MAO-A inhibition in 2013. With their growing importance, several studies on pyrazolines have constantly been reported for their MAO inhibitions. Therefore, in this review, we report up-to-date developments (after 2014) on pyrazolines as potential MAO inhibitors.

Insights into an Immunotherapeutic Approach to Combat Multidrug Resistance in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) has emerged as one of the most lethal cancers worldwide because of its high refractoriness and multi-drug resistance to existing chemotherapies, which leads to poor patient survival. Novel pharmacological strategies to tackle HCC are based on oral multi-kinase inhibitors like sorafenib; however, the clinical use of the drug is restricted due to the limited survival rate and significant side effects, suggesting the existence of a primary or/and acquired drug-resistance mechanism. Because of this hurdle, HCC patients are forced through incomplete therapy. Although multiple approaches have been employed in parallel to overcome multidrug resistance (MDR), the results are varying with insignificant outcomes. In the past decade, cancer immunotherapy has emerged as a breakthrough approach and has played a critical role in HCC treatment. The liver is the main immune organ of the lymphatic system. Researchers utilize immunotherapy because immune evasion is considered a major reason for rapid HCC progression. Moreover, the immune response can be augmented and sustained, thus preventing cancer relapse over the post-treatment period. In this review, we provide detailed insights into the immunotherapeutic approaches to combat MDR by focusing on HCC, together with challenges in clinical translation.