Medicinal Chemistry Research Articles

Anticancer Drug Development: Evaluative Architecture

Abstract: Anticancer drug development is complex and multi-factorial, demanding robust drug evaluative architecture in experimental and preclinical studies. To increase the number of drug licensing, biochemical, pharmacological, technical and economic changes (balance and integration) in evaluative systems should be focused in labs throughout the world. Despite great progress, treatment breakthroughs and drug industry need new ideas and more competitive technology (new generation of in vitro test systems). Overall, drug evaluative systems comprise anticancer drug development (medicinal chemistry and pharmacology) from initial screening to clinical validity. Its advances greatly impact the outcomes of drug production (rates of final drug licensing and efficacy of therapeutics in the clinic). In this regard, creative ideas and new techniques will change the norm and convention of drug screening and mechanic exploration in the future. This article provides multi-disciplinary approaches for experimental and preclinical anticancer drug evaluations, selections and combinations (chemistry and biomedicine). Future trends for drug evaluative systems are especially highlighted in in-depth, multilateral and multidisciplinary approaches.

Studying the stability of polymer nanoparticles by size exclusion chromatography of radioactive polymers

The properties of nanomedicines will influence how they can deliver drugs to patients reproducibly and effectively. For conventional pharmaceutical products, Chemistry, Manufacturing and Control (CMC) documents require monitoring stability and storage conditions. For nanomedicines, studying these important considerations is hindered by a lack of appropriate methods. In this paper, we show how combining radiolabelling with size exclusion chromatography, using a method called SERP, can inform on the in vitro degradation of polymers. Using nanoparticles composed of biodegradable poly(lactic acid) (PLA) and poly(lactic-co-glycolic acid) (PLGA), we show that SERP is more sensitive than dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA) to detect degradation. We also demonstrate that the properties of the polymer composition and the nature of the aqueous buffer affect polymer degradation. Importantly, we show that minute changes in stability that cannot be detected by DLS and NTA impact the pharmacokinetic of nanoparticles injected in vivo. We believe that SERP might prove a valuable method to document and understand the pharmaceutical quality of polymer nanoparticles.

Discovery of Novel Inhibitors of Cruzain Cysteine Protease of Trypanosoma cruz.

Chagas disease (CD) is a parasitic disease endemic in several developing countries. According to the World Health Organization, approximately 6-8 million people worldwide are inflicted by CD. The scarcity of new drugs, mainly for the chronic phase, is the main reason for treatment limitation in CD. Therefore, there is an urgent need to discover new targets for which new therapeutical agents could be developed. Cruzain cysteine protease (CCP) is a promising alternative because this enzyme exhibits pleiotropic effects by acting as a virulence factor, modulating host immune cells, and interacting with host cells. This systematic review was conducted to discover new compounds that act as cruzain inhibitors, and their effects in vitro were studied through enzymatic assays and molecular docking. Additionally, the advances and perspectives of these inhibitors are discussed. These findings are expected to contribute to medicinal chemistry in view of the design of new, safe, and efficacious inhibitors against Trypanosoma cruzi CCP detected in the last decade (2013-2022) to provide scaffolds for further optimization, aiming toward the discovery of new drugs.

Ruthenium(II)-Catalyzed Late-Stage Incorporation of N-Aryl Triazoles and Tetrazoles with Sulfonium Salts via C-H Activation.

The late-stage functionalization of active pharmaceutical ingredients is a key challenge in medicinal chemistry. Furthermore, N-aryl triazoles and tetrazoles are important structural motifs with the potential to boost the activity of diverse drug molecules. Using easily accessible dibenzothiophenium salts for the ruthenium-catalyzed C-H arylation, these scaffolds were introduced into a variety of bioactive compounds. Our methodology uses cost-efficient ruthenium, KOAc as a mild base and gives access to a plethora of highly decorated triazole and tetrazole containing drug derivatives.

Ruthenium(II)‐Catalyzed Late‐Stage Incorporation of N‐Aryl Triazoles and Tetrazoles with Sulfonium Salts via C–H Activation

The late‐stage functionalization of active pharmaceutical ingredients is a key challenge in medicinal chemistry. Furthermore, N‐aryl triazoles and tetrazoles are important structural motifs with the potential to boost the activity of diverse drug molecules. Using easily accessible dibenzothiophenium salts for the ruthenium‐catalyzed C–H arylation, these scaffolds were introduced into a variety of bioactive compounds. Our methodology uses cost‐efficient ruthenium, KOAc as a mild base and gives access to a plethora of highly decorated triazole and tetrazole containing drug derivatives.

The global patent landscape of emerging infectious disease monkeypox.

Monkeypox is an emerging infectious disease with confirmed cases and deaths in several parts of the world. In light of this crisis, this study aims to analyze the global knowledge pattern of monkeypox-related patents and explore current trends and future technical directions in the medical development of monkeypox to inform research and policy. A comprehensive study of 1,791 monkeypox-related patents worldwide was conducted using the Derwent patent database by descriptive statistics, social network method and linear regression analysis. Since the 21st century, the number of monkeypox-related patents has increased rapidly, accompanied by increases in collaboration between commercial and academic patentees. Enterprises contributed the most in patent quantity, whereas the initial milestone patent was filed by academia. The core developments of technology related to the monkeypox include biological and chemical medicine. The innovations of vaccines and virus testing lack sufficient patent support in portfolios. Monkeypox-related therapeutic innovation is geographically limited with strong international intellectual property right barriers though it has increased rapidly in recent years. The transparent licensing of patent knowledge is driven by the merger and acquisition model, and the venture capital, intellectual property and contract research organization model. Currently, the patent thicket phenomenon in the monkeypox field may slow the progress of efforts to combat monkeypox. Enterprises should pay more attention to the sharing of technical knowledge, make full use of drug repurposing strategies, and promote innovation of monkeypox-related technology in hotspots of antivirals (such as tecovirimat, cidofovir, brincidofovir), vaccines (JYNNEOS, ACAM2000), herbal medicine and gene therapy.

Phosphoric Acid Catalyzed N-Addition/ C-Addition Reaction of 3-Vinyl Indoles with Pyrazole/Pyrazolone to Construct Pyrazole-Substituted 3-(1-Heteroarylethyl)-indole Scaffolds.

Developing a highly efficient atom-economic method for the preparation of 3-(1-heteroarylethyl)-indole scaffolds is of significant value in pharmaceutical and agricultural chemistry. Herein, a phosphoric acid-catalyzed N-addition reaction of 3-vinyl indoles with pyrazoles and C-addition reaction of 3-vinyl indoles with pyrazolones were developed. A series of pyrazole-substituted 3-(1-heteroarylethyl)-indole scaffolds were synthesized in excellent yields (up to 99% yield) under mild reaction conditions. A reasonable reaction mechanism was proposed to explain the experimental results.

A Review: Applications of Ionic Liquids in Medicinal Chemistry

A Review: Applications of Ionic Liquids in Medicinal Chemistry

Cooperative Photoredox and Cobalt-catalyzed Acceptorless Dehydrogenative Functionalization of Cyclopropylamides towards Allylic N,O-Acyl-acetal Derivatives.

We disclose herein a novel photoredox and cobalt co-catalyzed ring-opening/acceptorless dehydrogenative functionalization of mono-donor cyclopropanes, which providing a sustainable and atom-economic approach to rapidlyassemble a wide range of allylic N,O-acyl-acetal derivatives.The optimized conditions accommodate assorted cycloalkylamides and primary, secondary and tertiary alcohols, with applications in late-stage functionalization of pharmaceutically relevant compounds, stimulating the further utility in medicinal chemistry. Moreover, selective nucleophilic substitutions with various carbon nucleophiles were succeed in a one-pot fashion, offering a reliable avenue to access some cyclic and acyclic derivatives.

Novel Stereo‐Induction Pattern in Pudovik Addition/Phospha‐Brook Rearrangement Towards Chiral Trisubstituted Allenes

AbstractDespite the significance of chiral allene skeletons in catalysis, organic synthesis and medicinal chemistry et al., there is a scarcity of reports on axially chiral allenyl phosphorus compounds. Here, we disclosed an efficient and straightforward cascade reaction between ethynyl ketones and phosphine oxides, resulting in a broad array of trisubstituted allenes incorporating a phosphorus moiety in high yields with excellent stereoselectivities facilitated by peptide‐mimic phosphonium salt (PPS) catalysis, Additionally, comprehensive series of mechanistic experiments have been conducted to elucidate that this cascade reaction proceeds via an asymmetric Pudovik addition reaction followed by a subsequent phospha‐Brook rearrangement that occurs concomitantly with kinetic resolution, representing a stereospecific rearrangement and protonation process facilitating central‐to‐axial chirality transfer in a cascade manner. We anticipate that our research will pave the way for a promising exploration of novel stereo‐induction pattern in the Pudovik addition/phospha‐Brook rearrangement cascade reaction.

Novel Stereo-Induction Pattern in Pudovik Addition/Phospha-Brook Rearrangement Towards Chiral Trisubstituted Allenes.

Despite the significance of chiral allene skeletons in catalysis, organic synthesis and medicinal chemistry et al., there is a scarcity of reports on axially chiral allenyl phosphorus compounds. Here, we disclosed an efficient and straightforward cascade reaction between ethynyl ketones and phosphine oxides, resulting in a broad array of trisubstituted allenes incorporating a phosphorus moiety in high yields with excellent stereoselectivities facilitated by peptide-mimic phosphonium salt (PPS) catalysis, Additionally, comprehensive series of mechanistic experiments have been conducted to elucidate that this cascade reaction proceeds via an asymmetric Pudovik addition reaction followed by a subsequent phospha-Brook rearrangement that occurs concomitantly with kinetic resolution, representing a stereospecific rearrangement and protonation process facilitating central-to-axial chirality transfer in a cascade manner. We anticipate that our research will pave the way for a promising exploration of novel stereo-induction pattern in the Pudovik addition/phospha-Brook rearrangement cascade reaction.

Pushing Boundaries: What's Next in Metal-Free C-H Functionalization for Sulfenylation?

The synthesis of thioether derivatives has been explored widely due to the potential application of these derivatives in medicinal chemistry, pharmaceutical industry and material chemistry. Within this context, there has been an increasing demand for the environmentally benign construction of C-S bonds via C-H functionalization under metal-free conditions. In the present article, we highlight recent developments in metal-free sulfenylation that have occurred in the past three years. The synthesis of organosulfur compounds via a metal-free approach using a variety of sulfur sources, including thiophenols, disulfides, sulfonyl hydrazides, sulfonyl chlorides, elemental sulfur and sulfinates, is discussed. Non-conventional strategies, which refer to the development of thioether derivatives under visible light and electrochemically mediated conditions, are also discussed. The key advantages of the reviewed methodologies include broad substrate scope and high reaction yields under environmentally benign conditions. This comprehensive review will provide chemists with a synthetic tool that will facilitate further development in this field.

Cooperative Photoredox and Cobalt‐catalyzed Acceptorless Dehydrogenative Functionalization of Cyclopropylamides towards Allylic N,O‐Acyl‐acetal Derivatives

We disclose herein a novel photoredox and cobalt co‐catalyzed ring‐opening/acceptorless dehydrogenative functionalization of mono‐donor cyclopropanes, which providing a sustainable and atom‐economic approach to rapidly assemble a wide range of allylic N,O‐acyl‐acetal derivatives. The optimized conditions accommodate assorted cycloalkylamides and primary, secondary and tertiary alcohols, with applications in late‐stage functionalization of pharmaceutically relevant compounds, stimulating the further utility in medicinal chemistry. Moreover, selective nucleophilic substitutions with various carbon nucleophiles were succeed in a one‐pot fashion, offering a reliable avenue to access some cyclic and acyclic derivatives.

Exploring student perceptions: Factors influencing academic performance in a school of pharmacy in Nigeria

Background: The failure and success rate of students in pharmacy school has been shown to be dependent on some courses that predict academic performance. The study identified factors that could impact failure and academic performances of pharmacy students at Obafemi Awolowo University. Methods: The study was a cross-sectional study of 219 undergraduate pharmacy students from third, fourth and fifth years of a school of pharmacy in Nigeria. A pre-tested questionnaire gathered data on demographics, course perceptions and academic factors. Descriptive and inferential statistics such as percentages, weighted averages, and Chi squared tests were used to analyse the data obtained at p < 0.05. Results: Financial constraints, family challenges, and a lack of peer interaction were significantly associated with repeating a year. Specific courses perceived as difficult included “Pharmaceutical organic chemistry” (PHC 202), “Practical pharmaceutics I” (PHA 201) and “Medicinal chemistry II” (PHC 402). Courses perceived as difficult, particularly in the fourth year, were notably linked to academic stress. Conclusion: The study identified specific factors and courses that affect pharmacy students’ performance in the Nigerian context. Policy makers and faculty can take vital feedback to adjust the training content, methods and assessment system to possibly deliver a holistic education to pharmacy students.     

Cobalt(III) Halide Metal-Organic Frameworks Drive Catalytic Halogen Exchange.

The selective halogenation of complex (hetero)aromatic systems is a critical yet challenging transformation that is relevant to medicinal chemistry, agriculture, and biomedical imaging. However, current methods are limited by toxic reagents, expensive homogeneous second- and third-row transition metal catalysts, or poor substrate tolerance. Herein, we demonstrate that porous metal-organic frameworks (MOFs) containing terminal Co(III) halide sites represent a rare and general class of heterogeneous catalysts for the controlled installation of chlorine and fluorine centers into electron-deficient (hetero)aryl bromides using simple metal halide salts. Mechanistic studies support that these halogen exchange (halex) reactions proceed via redox-neutral nucleophilic aromatic substitution (SNAr) at the Co(III) sites. The MOF-based halex catalysts are recyclable, enable green halogenation with minimal waste generation, and facilitate halex in a continuous flow. Our findings represent the first example of SNAr catalysis using MOFs, expanding the lexicon of synthetic transformations enabled by these materials.

A transformative oxidation process involving silver-based catalysis of para aminobenzyl alcohol for transposing a pollutant into a resource

ABSTRACT A kinetic-spectrophotometric method has been devised to analyze the oxidation reaction of Para-aminobenzyl alcohol [PABAlc] catalyzed by Ag (I). PABAlc is used in numerous fields of pharmaceutical and medicinal chemistry as intermediates. The harmful effects of PABAlc cannot be overlooked in spite of its manifold applications. The toxicity of PABAlc may lead to allergic reactions, serious eye damage, respiratory tract infections amongst few. It became utmost important to formulate a method to establish the presence of PABAlc in a particular sample of water in order to circumvent its proximity to common people. In our work, we have provided an insight to an oxidation process using PABAlc as substrate catalyzed by Ag (I) ions besides proposing a reaction mechanism of the reaction under study with substantial data in the form of different thermodynamic parameters like activation energy (55 kJ/mol−1), temperature coefficient (1.92), enthalpy of activation (52.89 kJ/mol−1), alongside deets related to various effects of oxidant, substrate, catalyst, temperature, pH, ionic strength, and so on, on reaction kinetics. Additionally, the product formed in the proposed mechanism has its commercial importance in the field of pharmacy, dyes, and so on, sufficient enough to put forward a rationale for the investigations.

Targeting PD-1/PD-L-1 immune checkpoint inhibition for cancer immunotherapy: success and challenges

The programmed death-1 receptor (PD-1) acts as a T-cell brake, and its interaction with ligand-1 (PD-L-1) interferes with signal transduction of the T-cell receptor. This leads to suppression of T-cell survival, proliferation, and activity in the tumor microenvironment resulting in compromised anticancer immunity. PD-1/PD-L-1 interaction blockade shown remarkable clinical success in various cancer immunotherapies. To date, most PD-1/PD-L-1 blockers approved for clinical use are monoclonal antibodies (mAbs); however, their therapeutic use are limited owing to poor clinical responses in a proportion of patients. mAbs also displayed low tumor penetration, steep production costs, and incidences of immune-related side effects. This strongly indicates the importance of developing novel inhibitors as cancer immunotherapeutic agents. Recently, advancements in the small molecule-based inhibitors (SMIs) that directly block the PD-1/PD-L-1 axis gained attention from the scientific community involved in cancer research. SMIs demonstrated certain advantages over mAbs, including longer half-lives, low cost, greater cell penetration, and possibility of oral administration. Currently, several SMIs are in development pipeline as potential therapeutics for cancer immunotherapy. To develop new SMIs, a wide range of structural scaffolds have been explored with excellent outcomes; biphenyl-based scaffolds are most studied. In this review, we analyzed the development of mAbs and SMIs targeting PD-1/PD-L-1 axis for cancer treatment. Altogether, the present review delves into the problems related to mAbs use and a detailed discussion on the development and current status of SMIs. This article may provide a comprehensive guide to medicinal chemists regarding the potential structural scaffolds required for PD-1/PD-L-1 interaction inhibition.

Chemical derivatization leads to the discovery of novel analogs of azotochelin, a natural siderophore, as promising anticancer agents.

Siderophores are structurally unique medicinal natural products and exhibit considerable therapeutic potential. Herein, we report the design and synthesis of azotochelin, a natural siderophore, and an extensive library of azotochelin analogs as a potential anticancer agent. We modified the carboxylic acid and the aromatic ring motifs of azotochelin using various chemical motifs. We tested the compounds against six different cancer cell lines (KB-3-1, SNB-19, MCF-7, K-562, SW-620, and NCI-H460) and a non-cancerous cell line (HEK-293) to assess the cytotoxicity. Among the twenty compounds tested, the IC50values of eight compounds (14, 32, 35-40, and 54) were between 0.7 to 2.0 μM against a lung cancer cell line (NCI-H460). Moreover, several compounds had a good cytotoxicity profile (IC50< 10 μM) against many tested cancer cell lines. The flow cytometry analysis showed that compounds36and38induce apoptosis in NCI-H460 in a dose-dependent manner. The cell cycle analysis indicated that compounds36and38significantly arrest the cell cycle at the S phase to block cancer cell proliferation in the NCI-H460 cell line. The study has produced various novel azotochelin analogs that are potentially effective anticancer agents and leads for further synthetic and medicinal chemistry exploration.

The Art and Science of Molecular Docking.

Molecular docking has become an essential part of a structural biologist's and medicinal chemist's toolkits. Given a chemical compound and the three-dimensional structure of a molecular target-for example, a protein-docking methods fit the compound into the target, predicting the compound's bound structure and binding energy. Docking can be used to discover novel ligands for a target by screening large virtual compound libraries. Docking can also provide a useful starting point for structure-based ligand optimization or for investigating a ligand's mechanism of action. Advances in computational methods, including both physics-based and machine learning approaches, as well as in complementary experimental techniques, are making docking an even more powerful tool. We review how docking works and how it can drive drug discovery and biological research. We also describe its current limitations and ongoing efforts to overcome them.

A promising future of metal-N-heterocyclic carbene complexes in medicinal chemistry: The emerging bioorganometallic antitumor agents.

Metal complexes based on N-heterocyclic carbene (NHC) ligands have emerged as promising broad-spectrum antitumor agents in bioorganometallic medicinal chemistry. In recent decades, studies on cytotoxic metal-NHC complexes have yielded numerous compounds exhibiting superior cytotoxicity compared to cisplatin. Although the molecular mechanisms of these anticancer complexes are not fully understood, some potential targets and modes of action have been identified. However, a comprehensive review of their biological mechanisms is currently absent. In general, apoptosis caused by metal-NHCs is common in tumor cells. They can cause a series of changes after entering cells, such as mitochondrial membrane potential (MMP) variation, reactive oxygen species (ROS) generation, cytochrome c (cyt c) release, endoplasmic reticulum (ER) stress, lysosome damage, and caspase activation, ultimately leading to apoptosis. Therefore, a detailed understanding of the influence of metal-NHCs on cancer cell apoptosis is crucial. In this review, we provide a comprehensive summary of recent advances in metal-NHC complexes that trigger apoptotic cell death via different apoptosis-related targets or signaling pathways, including B-cell lymphoma 2 (Bcl-2 family), p53, cyt c, ER stress, lysosome damage, thioredoxin reductase (TrxR) inhibition, and so forth. We also discuss the challenges, limitations, and future directions of metal-NHC complexes to elucidate their emerging application in medicinal chemistry.