Nitrile-containing pharmaceuticals: efficacious roles of the nitrile pharmacophore

Design, and synthesis of 2,4-thiazolidinedione substituted 1,3,5-triazine derivatives as anti-HIV agent via inhibition of reverse transcriptase along with anti-SARS CoV-2, antibacterial and antibiofilm activity

The present study demonstrated the design and synthesis of novel 1,2,4-thiazolidinedione substituted 1,3,5-triazine derivatives as putative inhibitors against various infective diseases. The title analogues were synthesized in a multi-step process, and their structures were verified through elemental analysis and a variety of spectral analyses (FT-IR, 1H NMR, 13C NMR, mass). Compounds 12a was identified as prospective lead compound against HIV-1 based on their high CDdocker interaction energy and stability among the developed derivatives, according to molecular docking and MD simulation experiments with HIV-1 RT. Compound 12a was found effective against HIV-1 in a cell-based experiment, preventing the virus from replicating in CEM-GFP cells infected with 0.5 MOI of HIV-1 NL4-1. In the RNA-dependent DNA polymerase (RDDP) activity of the HIV-1 RT enzyme using a cell free based RT assay, compound 12a showed a therapeutic index of 113 and an EC50 of 125.1 nM. All of the compounds inhibited SARS-CoV-2 replication in the VeroE6-GFP cell line to varying degrees; compound 10e, 12e, 12a, 12b, and 12c, in particular, showed considerable inhibitory activity. The compounds exhibited stronger antibacterial action against Gram-negative than Gram-positive bacteria in an antimicrobial assay, and a SAR analysis revealed that tri-substituted 1,3,5-triazine derivatives exhibited greater inhibitory activity than di-substituted ones. Additionally, 12d and 12e were found to be the most effective inhibitors of P. aeruginosa biofilms when tested against this bacterium. The most active inhibitors, 12a and 12e, were also tested for thermodynamic solubility at pH 7.4 via miniaturized shake-flask method. Here, their solubility was found to be significantly influenced by the presence of hydroxyl group and morpholine. In conclusion, our research demonstrated the significant inhibitory activity of 1,2,4-thiazolidinedione substituted 1,3,5-triazine derivatives against HIV, SARS-CoV-2, and bacterial microorganisms.

C-H bond cyanation: electrochemical synthesis of phenylbenzimidoyl cyanide derivatives

The application of electricity in chemical processes represents a sustainable technology for the future. This green activation mode derives from renewable energy sources (such as solar, wind, and hydropower), safeguarding resources by being less polluting and utilizing less materials. C-H bond functionalisation is one of the most powerful synthetic methods for forging molecular complexity to access valuable chemicals in a single step transformation. Herein, an electrochemical C-H bond cyanation of imine derivatives under electrochemical reaction conditions has been developed. This is a new, simple, fast and non-toxic way for the direct cyanation of imine derivatives. Acetonitrile was found to be a new and effective cyanation reagent under catalyst-free electrochemical conditions. The cyanation protocol can be applied to diverse substrates including substituted and unsubstituted imine derivatives. The electrochemical method has been carried out in an undivided cell at constant current at 0 °C for 1 h using a Carbon rod as cathode and a magnesium plate as anode.

Manganese-Ketenimine Intermediates as Active Catalysts in the Michael Addition of Unactivated Nitriles to α,β-Unsaturated Ketones

The Michael addition of unactivated nitriles to α,β-unsaturated ketones is a challenging yet desirable strategy for installing alkyl cyano-groups (R-CN) in organic molecules. However, despite formidable efforts, using acetonitrile as a Michael donor in these reactions has remained a significant challenge. Herein, we report a highly active manganese(I) complex [(PCNHCP)Mn(CO)2H] (1), which chemoselectively catalyzes the 1,4-addition of unactivated nitriles (incl. acetonitrile) to α,β-unsaturated ketones. The developed methodology operates under mild conditions, does not require any additives or bases, features low catalyst loadings (1 mol %), fast reaction times (2-8 hours), and is compatible with a wide variety of functional groups, including halides, trifluoromethyl, alkenyl, alkynyl, and (hetero)aryl groups. Extensive mechanistic studies revealed that after base-free activation of the nitrile, either the N-bound manganese-ketenimine (propionitrile or benzyl cyanide) or the C-bound manganese-cyanoalkyl (acetonitrile) complex is formed. The difference in stability of these two species explains why more sterically hindered and presumably less activated nitriles (i.e., propionitrile, and butyronitrile) show higher reactivity than their corresponding more activated congeners (i.e., acetonitrile). Finally, the practicality of our approach was demonstrated through a gram-scale reaction and subsequent derivatizations of the obtained product into important organic motifs such as ene-lactams and tetrahydropyridines.

A transition metal-free [3 + 2] cycloaddition approach for the efficient synthesis of trisubstituted pyrrole derivatives from β-chlorovinyl aldehydes

A transition metal-free, Cs2CO3-promoted approach has been devised for the efficient synthesis of nitrile-substituted novel pyrrole derivatives from β-chlorovinyl aldehydes. Interestingly, the strategy was also found to be applicable to the synthesis of chromenone-fused pyrrole derivatives. The reaction proceeded through [3 + 2] cycloaddition between diversely substituted aryl propiolonitriles and toluenesulphonylmethyl isocyanide in DMF at ambient temperature. This approach offers several advantages including the use of inexpensive and readily available starting materials, wide substrate scope, operational simplicity, short reaction times (15 min-1.5 h), high atom economy, sustainable reaction conditions and high product yields. The strategy has been found to be amenable for gram-scale synthesis, and the scope of the strategy has been demonstrated for the synthesis of a diverse library of novel pyrrole derivatives with yields of up to 91%. The generated pyrrole derivatives are amenable for late-stage functionalisation and functional group interconversion.

Regioselective formal hydrocyanation of allenes: synthesis of β,γ-unsaturated nitriles with α-all-carbon quaternary centers

This study introduces a highly selective hydrocyanation method based on copper-catalyzed hydroalumination of allenes with diisobutylaluminum hydride, followed by the regio- and stereoselective allylation with p-toluenesulfonyl cyanide. The proposed methodology is efficient for accessing acyclic β,γ-unsaturated nitriles with α-all-carbon quaternary centers and achieves yields up to 99% and excellent regio- and E-selectivity. The reaction proceeds under mild conditions and shows broad applicability to di- and trisubstituted allenes. Its practicality is demonstrated through the gram-scale synthesis and functional group transformations of amines, amides, and lactams, emphasizing its versatility and synthetic significance.

Easy access to 5-cyanotriazoles via Pd-catalyzed cyanation of 5-iodotriazoles

A straightforward approach for the attachment of a nitrile moiety to the 1,2,3-triazole core has been developed. The protocol is based on the cyanation of 5-iodo-1,2,3-triazoles which are readily accessible by Cu-catalyzed azide-iodoalkyne cycloaddition. Halogen substitution occurs smoothly with KCN as a cyanide source using a Pd(0)-Dpephos catalytic system. The reaction tolerates a variety of functional groups as well as some sensitive heterocyclic scaffolds and affords the target 5-cyano-1,2,3-triazoles in yields of up to 99%. Further transformations of the nitrile group enable an easy preparation of 1,2,3-triazoles bearing diverse moieties, including amides, amines, and some azaheterocycles.

Synthesis of indole-linked β-cyano-enones: a pathway to indolyl-2-pyrrolones

Herein, we report for the first time an additive- and catalyst-free dehydrogenative multicomponent reaction of arylglyoxal, malononitrile, and indoles for the one-pot synthesis of indole-linked β-cyano-enones in DMF medium. The reaction was performed at 100 °C in DMF, forming one C-C single bond and one CC double bond in a single-flask. Furthermore, we developed an efficient method for the synthesis of indolyl-2-pyrrolones having a hydroxyl group-containing chiral carbon center from the β-cyano-enones using trifluoroacetic acid and water as reaction medium. The β-cyano-enones were also further transformed into indolyl-1,2-diketones via a base-mediated reaction, which yielded indolyl quinoxalines upon reaction with o-phenylenediamine (OPD).

Catalyst and transition-metal free 1,6-conjugate addition of azobisisobutyronitrile: access to isobutyronitrile containing diarylmethanes

A catalyst and transition-metal free 1,6-conjugate addition of azobisisobutyronitrile to para-quinone methides for the synthesis of isobutyronitrile containing diarylmethanes has been achieved. This protocol enables the synthesis of isobutyronitrile containing diarylmethanes in good yields and with a broad substrate scope. This is the first example wherein azobisisobutyronitrile has been used as a cyanide source for 1,6-conjugate addition under catalyst and metal-free conditions.

Calcium catalysed Strecker-type reactions towards α-aminonitriles

We report an operationally simple calcium catalysed Strecker type reaction for the synthesis of α-aminonitriles from readily available N,O-acetals. The reaction is tolerant to a wide range of useful functional groups, including heterocycles, and provides the product in good to excellent yields. Additionally, the reaction does not require the need for anhydrous or air-free conditions, making it a suitable candidate for high throughput experimentation.

Nitrogen Insertion via Asymmetric Condensation and Chirality Transfer: A Stereodivergent Entry to Cyanocyclopropanes

The condensation of prochiral cyclobutanones and diphenylphosphinyl hydroxylamine is achieved under Brønsted acid catalysis. Interestingly, the competing aza-Baeyer-Villiger reaction is completely suppressed and the axially chiral oxime esters can be isolated in excellent yield and selectivity (up to 96% yield, up to 97:3 er). Computational analysis highlights the crucial role of the Brønsted acid in facilitating a successful condensation. Building on the inherent reactivity of the corresponding oxime esters, a one-pot protocol toward cyanocyclopropanes was discovered, which establishes two consecutive stereocenters. This unusual ring contraction is triggered by strong base and permits an axial-to-point chirality transfer with good enantiospecificity (up to 98% es). Fine-tuning the reaction parameters enables stereodivergent access to both diastereomers of the cyanocyclopropanes, and the utility of this method is demonstrated through the formal synthesis of the drug tasimelteon.

1,2-Acylcyanation of Styrenes by Photoinduced Nickel Catalysis to Generate Acyl Radicals from Acyl Fluorides

We report herein a photoinduced nickel-catalyzed 1,2-acylcyanation of styrenes with acyl fluorides and trimethylsilyl cyanide (TMSCN). Nickel(II) acyl complexes, formed from nickel(0) complexes and acyl fluorides, are photoexcited to generate acyl radicals via a ligand-to-metal charge transfer (LMCT) process. This transformation proceeds under mild conditions and thus can be applied to the late-stage functionalization (LSF) of natural product derivatives. Synthetic derivatizations show the utility of the products. The preparation of aza-DIPYs is also demonstrated.

Stereoselective synthesis of tetra- and tri-substituted alkenyl nitriles via aminative ring-opening of cyclopropenes with iron-aminyl radical

The ring opening of cyclopropenes provides a compelling platform for the rapid synthesis of various polysubstituted acyclic alkenes. However, radical-mediated reactions of this type remain underexplored, and none of the existing methods have successfully produced tetrasubstituted olefins with high stereoselectivity. We present here an aminative ring-opening of cyclopropenes with iron-aminyl radical to afford tetrasubstituted alkenyl nitriles in a highly stereoselective manner. Computational studies indicate that both the substrate-directed radical addition and the following stereospecific ring-opening of cyclopropyl radical contribute to the extraordinary stereocontrol observed in the reaction. In addition, trisubstituted alkenyl nitriles could also be obtained using this method or via a base-promoted isomerization of the tetrasubstituted alkenyl nitriles, both with consistently high stereoselectivity.

Ferrocene Catalyzed Radical Cascade Cyclization of Aryl 1,6-Diynes: Access to Cyanoalkylsulfonyl Fluorenes

A ferrocene-catalyzed cyanoalkylsulfonylative radical cascade cyclization of aryl 1,6-diynes using cycloketone oxime esters and DABCO.(SO₂)₂ (DABSO) is reported. The reaction proceeds with notable chemo- and regioselectivity, without requiring additional oxidants or reductants. Interestingly, the methodology facilitates the formation of an unprecedented dicyanoalkylsulfonylated derivative in the case of electronically deficient aryl 1,6-diynes. Additionally, this transformation is compatible with substrates derived from drugs and bioactive molecules, highlighting its synthetic utility.

Acceptorless oxidant-free dehydrogenation of amines catalyzed by Ru-hydride complexes of amide-acid/ester ligands

Traditional dehydrogenation of amines involves the transfer of hydrogen molecule(s) from a substrate to an acceptor. In acceptorless dehydrogenation, hydrogen gas is liberated without an oxidant, providing an efficient synthetic method. Acceptorless dehydrogenation of primary amines to nitriles without using an oxidant or hydrogen acceptor is significant yet challenging. Herein, we present efficient Ru-based catalysts capable of carrying out such a transformation with hydrogen gas as the only by-product. A new class of air and moisture-stable ruthenium-hydride complexes (1-4) of amide-acid/ester-based ligands have been synthesized and characterized. Crystal structures of two representative complexes, 2 and 3, illustrate the bidentate N-O coordination mode of the ligands. At the same time, additional binding sites are occupied by one hydride, one CO, and two PPh3 co-ligands. The catalytic behavior of these complexes is explored towards the oxidant-free, acceptorless, and selective dehydrogenation of primary and secondary amines affording nitriles and imines, respectively. Among four Ru(II) complexes, complex 2 showed the best catalytic activity for the dehydrogenation of amines. A wide variety of both primary and secondary amines were utilized to explore the substrate scope. The catalytic system tolerated both electron-withdrawing and electron-releasing substituents on amine substrates. Various control experiments and mechanistic studies were carried out to support the dehydrogenation of amines by using complex 2 as a representative catalyst.

Arene and Heteroarene Functionalization Enabled by Organic Photoredox Catalysis

ConspectusAromatic functionalization reactions are some of the most fundamental transformations in organic chemistry and have been a mainstay of chemical synthesis for over a century. Reactions such as electrophilic and nucleophilic aromatic substitution (EAS and SNAr, respectively) represent the two most fundamental reaction classes for arene elaboration and still today typify the most utilized methods for aromatic functionalization. Despite the reliable reactivity accessed by these venerable transformations, the chemical space that can be accessed by EAS and SNAr reactions is inherently limited due to the electronic requirements of the substrate. In the case of EAS, highly active electrophiles are paired with electron-neutral to electron-rich (hetero)arenes. For SNAr, highly electron-deficient (hetero)arenes that possess appropriate nucleofuges (halides, -NO2, etc.) are required for reactivity. The inherent limitations on (hetero)arene reactivity presented an opportunity to develop alternative reactivity to access increased chemical space to expand the arsenal of reactions available to synthetic chemists.For the past decade, our research has concentrated on developing novel methods for arene functionalization, with a particular focus on electron-neutral and electron-rich arenes and applying these methods to late-stage functionalization. Specifically, electron-rich arenes undergo single electron oxidation by a photoredox catalyst under irradiation, forming arene cation radicals. These cation radicals act as key intermediates in various transformations. While electron-rich arenes are typically unreactive toward nucleophiles, arene cation radicals are highly reactive and capable of engaging with common nucleophiles.This Account details the dichotomy of reactivity accessed via arene cation radicals: C-H functionalization by nucleophiles under aerobic conditions or cation radical accelerated nucleophilic aromatic substitution (CRA-SNAr) in anaerobic settings. Based on experimental and computational studies, we propose that reversible nucleophilic addition to arene cation radicals can occur at the ipso-, para-, or ortho-positions relative to the most electron-releasing group. Under aerobic conditions, intermediates formed by para- or ortho-addition typically undergo an additional irreversible oxidation step, resulting in C-H functionalization as the major outcome. Conversely, in the absence of an external oxidant, C-H functionalization is not observed, and ipso-addition predominates, releasing an alcohol or HF nucleofuge, leading to SNAr products. Building on the success of these arene functionalization transformations, we also explored their applications to positron emission tomography (PET) radiotracer development. Both C-H functionalization and SNAr with 18F- and 11CN- have been applied to radiofluorination and radiocyanation of arenes, respectively. Applications of the radiotracers synthesized by these methods have been demonstrated in preclinical and clinical models.

Near-Infrared-Light-Induced Iron(I) Dimer Enabled Abstraction of Ester Group from Cycloketone Oxime Esters

Photoinduced dimeric metal complexes have been extensively utilized in halogen atom transfer (XAT) reactions. In this study, we successfully achieved the abstraction of ester group from cyclobutanone oxime esters via iron(I)-dimer catalysis under near-infrared (NIR) light (730 nm) excitation, enabling the efficient synthesis of cyanoalkylated alkenes, quinazolinones, and 3,3-disubstituted oxindoles. Mechanistic investigations confirmed the NIR-induced functional group abstraction process.

Difluorocarbene-Enabled Dehydration of Primary Amides To Access Nitriles

A cost-effective and environmentally friendly method for the direct conversion of primary amides to nitriles was developed using commercially available non-toxic ethyl bromodifluoroacetate as a difluorocarbene precursor under metal-free and ligand-free conditions. The reaction features high yields and tolerates various sensitive moieties, including alkyl, alkenyl, ether, sulfone, sulfoxide, heteroaryl, chloro, bromo, iodo, hydroxyl, nitro, and cyano groups, and late-stage modification of complex molecules is also feasible. Moreover, the present method is effective on large scales, showing potential for industrial application.

Enantioselective Biosynthesis of (+)- and (-)-Auranthines

In nature, organisms produce various bioactive natural products (NPs). Most NPs target naturally occurring macromolecules, such as proteins and nucleotides. Thus, NPs are produced in a stereocontrolled manner except for the cases where nonenzymatic reactions are involved in the biosynthesis. This is why stereoisomers, especially enantiomers, are rarely found among metabolites from natural sources. During the biosynthetic study of auranthine, a fungal NP containing a nitrile group, we discovered that the (-)-isomer of auranthine (1) is produced by Aspergillus lentulus strains isolated in Japan, while a previously unreported (+)-enantiomer 2 is produced by those isolated elsewhere. The biosynthetic genes for both isomers were determined by transcriptomic, gene deletion, and heterologous expression experiments, revealing that two different nonribosomal peptide synthetases (NRPSs) NitA and NitC were involved in the biosynthesis of 1 and 2, respectively. Both NitA and NitC are bimodular NRPSs, as is the case for the asperlicin-synthesizing enzyme AspA. All incorporate two molecules of anthranilic acid and one molecule of amino acid to form the peptide core. However, only NitC contains an epimerization domain, suggesting that is how the enantiomeric pair is biosynthesized by NitA and NitC. Furthermore, biosynthesis of the nitrile-bearing l-γ-cyanohomoalanine that is incorporated into 1 and 2 was found to be catalyzed by an argininosuccinate synthetase-like NitB using l-glutamine as a substrate. This study reports not only the unique mechanism of nitrile-containing amino acid biosynthesis but also the intriguing production of an enantiomeric pair of secondary metabolites by different strains of the same fungal species (250/250).

Synthesis of Multisubstituted Arylnitriles via Tf2O-Mediated Benzannulation of Enaminones with Acylacetonitriles

A novel and efficient method for the synthesis of multisubstituted arylnitriles via Tf2O-mediated [3 + 2 + 1] benzannulation of enaminones and acylacetonitriles has been developed. This reaction proceeds under mild conditions with excellent functional group compatibility. Mechanistic studies have revealed that the cyclization involves two consecutive nucleophilic additions, followed by a cascade Knoevenagel condensation and aromatization. Additionally, trifluoromethanesulfonate 6 has been identified as a crucial intermediate in this process.

Recent advances in electrochemical 1,2-difunctionalization of alkenes: mechanisms and perspectives

In recent years, significant achievements have been made in the field of electroorganic chemistry regarding the difunctionalization of alkenes. Researchers have developed innovative strategies utilizing the unique reactivity of electrochemical processes to synthesize complex molecules with high regioselectivity and stereoselectivity. This technology is widely applied in the total synthesis of natural products and in the pharmaceutical industry. This article reviews the research progress in the electrochemical difunctionalization of alkenes through three different radical-mediated pathways over the past five years. It includes discussions on 1,2-stereoselective and non-diastereoselective difunctionalization reactions, rearrangements, intramolecular migrations, and cyclization processes. The summary emphasizes innovative electrode designs, reaction mechanisms, and the integration with other emerging technologies, highlighting the potential of this method in modern organic chemistry. Additionally, it aims to address current challenges and propose possible solutions, providing a promising direction for electrochemically mediated difunctionalization reactions of alkenes.

Nickel-Catalyzed Reductive Hydrolysis of Nitriles to Alcohols

Nitriles are an abundant class of compounds that are widely used as versatile feedstocks to produce various chemicals including pharmaceuticals, and agrochemicals as well as materials. Here we report Ni-catalyzed reductive hydrolysis of nitriles to alcohols in the presence of molecular hydrogen. This conversion likely occurs in a domino reaction sequence that first involves the hydrogenation of nitrile to primary imine, then the hydrolysis of imine, and subsequent deamination to the aldehyde, which is finally hydrogenated to the desired alcohol. Crucial for this reductive hydrolysis process is the commercially available triphos-ligated Ni-complex that enables highly efficient and selective transformation of aromatic, heterocyclic, and aliphatic nitriles including fatty nitriles to prepare functionalized primary alcohols. Further, the synthetic applicability of this Ni-based protocol is presented for the selective conversion of nitrile to alcoholic group in structurally diverse and complex drug molecules as well as agrochemicals. The resulting products, alcohols are indispensable chemicals commonly used in organic synthesis and life sciences as well as material and energy technologies.

Mechanistic insights into novel cyano-pyrimidine pendant chalcone derivatives as LSD1 inhibitors by docking, ADMET, MM/GBSA, and molecular dynamics simulation

Cancer presents a formidable and complex foe, standing as one of the foremost contributors to disease-related fatalities across the globe. According to data from the Global Cancer Observatory (GLOBOCAN), projections indicate a staggering 28.4 million cases of cancer, encompassing both new diagnoses and deaths, by 2040. Therefore, developing effective and comprehensive treatment approaches for cancer patients is essential and the conventional approved treatments for cancers are associated with various harmful side effects. Our study aims to address the critical and widespread need for alternative therapies that can effectively combat cancer with minimal side effects. The present contribution outlines a targeted approach using Lysine Specific Demethylase 1 (LSD1) to evaluate novel cyano-pyrimidine pendant chalcone derivatives as potential antiproliferative agents. Two sets of novel cyano-pyrimidine pendant chalcone derivatives were produced, and molecular docking was performed on the LSD1 protein. The ligands A1 and B1 belonging to series A and B, respectively, were found to have the highest docking scores of -11.095 and -10.773 kcal/mol, in that order. The ADME and toxicity studies of the ligands showed promising responses with respect to various pharmacokinetic and physicochemical parameters. The Molecular dynamics (MD) simulation results indicated effective diffusion of both complexes inside the protein cavity, facilitated by prominent interactions with various amino acids. Additionally, the complexes displayed high relative binding free energy. The computational screening of ligands indicates that ligands A1 and B1 exhibit potential for further exploration using various in vitro and in vivo techniques. These ligands may then serve as promising leads in the discovery of cancer drugs. The in-silico screening of the novel library of cyano-pyrimidine pendant chalcone derivatives was performed with a combination of molecular docking, MM-GBSA, ADME, toxicity and MD simulation. Molecular docking and MM-GBSA were conducted using the Glide and Prime tools, respectively, of the Schrödinger suite 12.8. The ligands were analysed for ADME using the Swiss ADME, while toxicity risks were evaluated using Osiris Property Explorer. Additionally, a 400ns MD simulation of LIGA1 and LIGB1 against the protein LSD1 was performed using the Desmond tool of Schrödinger suite 12.8 to validate the docking results and analyse the behaviour and stability of the complexes.

Design, Synthesis, Antiproliferative Screening, and In Silico Studies of Some Pyridinyl‐Pyrimidine Candidates

Using pyrimidinethione, a new series of pyridinyl‐pyrimidine candidates was prepared by reacting with diverse carbon‐centered electrophiles like hydrazonoyl chloride, N‐arylchloroacetamide, ethyl chloroacetate, and enaminone derivatives. Some heteroannulated compounds, such as triazolopyrimidine and thiazolopyrimidine derivatives were obtained. The mass fragmentation pathways were investigated by the electron impact mass spectrometry (EI‐MS), and the molecular ion peaks (M+.) were recorded at different intensities. The in vitro antiproliferative efficacy of the prepared compounds against MCF7 and HCT116 cancer cell lines showed the highest potency of pyrimidinethione 2, triazolopyrimidine 4, and thiazolopyrimidine 10. Also, in silico studies were performed to recognize these findings. A molecular docking simulation towards the EGFR enzyme showed the best docking score of thiazolopyrimidine 10 through H‐bonding and hydrophobic interactions in comparison to the interactions of co‐crystallized ligand and doxorubicin. With DFT calculations, compound 10 exhibited the lowest energy gap and the highest softness. Among ADME simulation, compounds 7, 8, 9, and 11 exhibited desirable lead‐likeness. It is hoped that this work may affect advancing new effective antiproliferative agents.

Advances in reversible covalent kinase inhibitors

Reversible covalent kinase inhibitors (RCKIs) are a class of novel kinase inhibitors attracting increasing attention because they simultaneously show the selectivity of covalent kinase inhibitors yet avoid permanent protein-modification-induced adverse effects. Over the last decade, RCKIs have been reported to target different kinases, including Atypical group of kinases. Currently, three RCKIs are undergoing clinical trials. Here, advances in RCKIs are reviewed to systematically summarize the characteristics of electrophilic groups, chemical scaffolds, nucleophilic residues, and binding modes. In so doing, we integrate key insights into privileged electrophiles, the distribution of nucleophiles, and hence effective design strategies for the development of RCKIs. Finally, we provide a further perspective on future design strategies for RCKIs, including those that target proteins other than kinases.

High-throughput Experimentation Enables the Development of a Nickel-catalyzed Cyanation Platform for (Hetero)aryl Halides

A novel screening platform for the nickel-catalyzed cyanation of (hetero)aryl halides relying on the use of air-stable Ni(COD)DQ at low loading is reported. Through high-throughput experimentation (HTE), various ligand and solvent combinations are systematically explored, allowing the fast identification of suitable conditions. This standardized workflow serves as an excellent starting point for selecting other competent nickel precatalysts and for further optimization of reluctant substrates. The transformation exhibits broad functional group tolerance and can be readily scaled up to gram-scale.

Transformative reactions in nitroarene chemistry: C-N bond cleavage, skeletal editing, and N-O bond utilization

Nitroarenes are highly versatile building blocks in organic synthesis, playing a pivotal role in various reactions. Common transformations involving nitroarenes include nucleophilic aromatic substitution (SNAr) reactions, where the nitro group functions both as a potent electron-withdrawing group that activates the aromatic ring and as a leaving group facilitating the substitution. Additionally, the direct transformation of nitro groups, such as reduction-driven syntheses of amines and carboxylic acids, as well as ipso-substitution SNAr reactions, have been extensively explored. Interactions between ortho-nitro groups and neighboring substituents also provide unique opportunities for selective transformations. However, beyond these well-established processes, direct transformations of nitro groups have been relatively limited. In recent years, significant advancements have been made in alternative methodologies for nitro group transformations. This review focuses on the latest progress in novel transformations of nitroarenes, with emphasis on three major categories: (i) functional group transformations involving C-N bond cleavage in nitroarenes, (ii) skeletal editing via nitrene intermediates generated by N-O bond cleavage, and (iii) the utilization of nitroarenes as an oxygen source through N-O bond cleavage. These developments under-score the expanding utility of nitroarenes in modern organic synthesis.

Dibenzothiophenium Salts: Practical Alternatives to Hypervalent I(III)-Based Reagents

ConspectusDuring the past few years, the interest among organic synthesis practitioners in the use of sulfonium salts has exponentially growth. This can arguably be attributed to a series of specific factors: (a) The recent development of more direct and efficient protocols for the synthesis of these species, which make sulfonium reagents of a wide structural variety easily available in multigram scale. (b) The recognition that the reactivity of these salts resembles that of hypervalent iodine compounds, and therefore, they can be used as effective replacement of such species in most of their applications. (c) Their intrinsic thermal stability and tolerance to air and moisture, which clearly surpass that of I(III)-reagents of analogue reactivity, and facilitate their purification, isolation as well-defined species, storage, and safely handling on larger scale. (d) Finally, the possibility to further functionalize sulfonium salts once the sulfur-containing platform has been incorporated. Specifically, this last synthetic approach is not trivial when working with hypervalent I(III)-species and facilitates the access to sulfonium salts with no counterpart in the I(III) realm.This renewed interest in sulfonium salts has led to the improvement of already existing transformations as well as to the discovery of unprecedented ones; in particular, by the development of protocols that incorporate sulfonium salts as partners in traditional cross-coupling and C-H activation steps or combine them with more modern technologies such as photocatalysis or electrosynthesis. In this Account, the reactivity of a series of sulfonium salts originally prepared in our laboratory will be outlined and compared to their I(III)-counterparts. Some of these reagents are now commercially available, and their use has started to spread widely across the synthetic chemistry community, helping to speed the process of identification of potentially bioactive products or new functionaliced materials. However, challenges still remain. The development of sulfonium reagents characterized by an optimal balance between reactivity and site-selectivity, or showing broader compatibility toward sensitive functional groups is still a need. In addition, the intrinsic stability of sulfonium salts often makes necessary the use of (sophisticated) catalysts that activate the latent reactivity hidden in their structures. Although a priori one can see this fact as a disadvantage, it might actually be decisive to harvest the full synthetic potential of sulfonium salts because their thermal stability will surely facilitate the preparation of operational reagents with no counterpart in the context of I(III)-chemistry. If this becomes true, sulfonium salts may contribute to the expediting of retrosynthetic disconnections that, to date, are impossible.

JAK3 Inhibitors: Covalent and Noncovalent Interactions of a Cyanamide Group Investigated by Multiscale Free-Energy Simulations

Janus kinase type 3 (JAK3), an emerging target for treating autoimmune diseases, possesses a front pocket cysteine that is targeted by covalent modifiers, best represented by the marketed drug ritlecitinib (1). Recently, 2,3-dihydro-1H-inden-1-ylcyanamides have been developed as novel JAK3 inhibitors. Among them, the N-(6-(7H-pyrrolo[2,3-d]pyrimidin-4-yl)-2,3-dihydro-1H-inden-1-yl)cyanamide inhibitor (2) and its methylated analogue (3), while being potent inhibitors, displayed different mechanisms of action (covalent vs noncovalent) and binding modes (Casimiro-Garcia et al., J Med Chem 2018). Prompted by this intriguing behavior, we applied a multiscale approach to characterize the reaction mechanism between the JAK3 front-pocket Cys909 and cyanamide-based inhibitors. Quantum mechanics/molecular mechanics simulations showed that 2 can readily form an isothiourea adduct with the Cys909 only when a conserved water molecule assists the reaction as a proton shuttle and that methylation of the 2,3-dihydro-1H-inden-1-ylcyanamide moiety of 2 hampers the isothiourea formation by displacing this water molecule. Metadynamics and thermodynamic integration simulations were applied to investigate the relative abundance of alternative poses accessible to 2,3-dihydro-1H-inden-1-ylcyanamides, explaining the effect of methylation on the relative binding mode preference. This multiscale approach provides new chemical insights into the mechanism of action of cyanamide inhibitors and emerges as an effective protocol to investigate the interaction between drugs and molecular targets.

Ruthenium-Catalyzed Remote Trifunctionalization of Non-Activated Alkenes via Cyano Migration and meta-C(sp2)-H Functionalization

A novel Ru-catalyzed radical-triggered trifunctionalization of hexenenitriles is presented, employing a strategy of remote cyano group migration and meta-C(sp2)-H functionalization. Through remote cyano migration, the alkenyl moiety undergoes difunctionalization to the formation of a benzylic radical intermediate. This intermediate facilitates para-selective C-H bond addition relative to the C-Ru bond within the Ru(III) complex, ultimately enabling trifunctionalization. This methodology provides an efficient route to a diverse array of nitrile-containing compounds with broad functional group compatibility.

l-Proline catalysed synthesis and in silico studies of novel α-cyano bis(indolyl)chalcones as potential anti-cancer agents

A diverse range of α-cyano bis(indolyl)chalcones (21a-r) were synthesized in high yields (90-95%) through the l-proline catalysed reaction of appropriate aldehydes and 3-cyanoacetylindoles. Formation of α-cyano bis(indolyl)chalcones involves readily available starting materials, catalytic l-proline, environmentally benign and metal-free conditions. The prepared eighteen α-cyano bis(indolyl)chalcones 21a-r were screened against prostate, breast, epithelial cancer cells and found to be non-cytotoxic to normal HEK293 cells. The α-cyano bis(indolyl)chalcones 21a (3.9 μM), 21c (7.5 μM), 21i (2.2 μM) and 21o (5.9 μM) displayed good cytotoxicity against C4-2 cells, whereas, derivatives 21c (1.23 μM), 21h (5.23 μM), and 21l (2.5 μM) showed selective cytotoxicity against 22Rv1 cells. With broad spectrum of activity (0.98-5.6 μM), the compound 21j was found to increase the endogenous level of ROS, upregulate the level of p-53 and c-jun besides mitochondrial dysfunction, cause apoptosis.

Palladium-Catalyzed Asymmetric Acetoxylative Cyclization/Acyl Transfer Cascade of Alkyne-Tethered Malononitriles with Carboxylic Acids

Palladium-catalyzed asymmetric intermolecular trans-acetoxypalladation/desymmetric cyclization/acyl transfer cascades of alkyne-tethered malononitriles with carboxylic acids have been demonstrated. Such a sequence enables the formation of multifunctionalized nitriles bearing α-all-carbon quaternary stereocenters with a high degree of enantiocontrol with a broad substrate scope. Moreover, synthetic elaborations present these multifunctionalized molecules as promising chiral building blocks. Mechanistic studies illustrate that the cascade process proceeds via a key imine intermediate, and the desymmetric cyclization is the enantio-determining step.

Glucosinolates and Their Hydrolytic Derivatives: Promising Phytochemicals With Anticancer Potential

Recent research has increasingly focused on phytochemicals as promising anticancer agents, with glucosinolates (GSLs) and their hydrolytic derivatives playing a central role. These sulfur-containing compounds, found in plants of the Brassicales order, are converted by myrosinase enzymes into biologically active products, primarily isothiocyanates (ITCs) and indoles, which exhibit significant anticancer properties. Indole-3-carbinol, diindolylmethane, sulforaphane (SFN), phenethyl isothiocyanate (PEITC), benzyl isothiocyanate, and allyl isothiocyanate have shown potent anticancer effects in animal models, particularly in breast, prostate, lung, melanoma, bladder, hepatoma, and gastrointestinal cancers. Clinical studies further support the chemopreventive effects of SFN and PEITC, particularly in detoxifying carcinogens and altering biochemical markers in cancer patients. These compounds have demonstrated good bioavailability, low toxicity, and minimal adverse effects, supporting their potential therapeutic application. Their anticancer mechanisms include the modulation of reactive oxygen species, suppression of cancer-related signaling pathways, and direct interaction with tumor cell proteins. Additionally, semi-synthetic derivatives of GSLs have been developed to enhance anticancer efficacy. In conclusion, GSLs and their derivatives offer significant potential as both chemopreventive and therapeutic agents, warranting further clinical investigation to optimize their application in cancer treatment.

Scaled and Weighted Laplacian Matrices as Functional Descriptors for GPCR Ligands

The G protein-coupled receptor (GPCR) pharmacology accounts for a significant field in research, clinical studies, and therapeutics. Computer-aided drug discovery is an evolving suite of techniques and methodologies that facilitate accelerated progress in drug discovery and repositioning. However, the structure-activity relationships of molecules targeting GPCRs are highly challenging in many cases since slight structural modifications can lead to drastic changes in biological functionality. Numerous molecular descriptors have been described, many of which successfully characterize the structural and physicochemical features of drug sets. Nonetheless, elucidating the structure-functionality relationships over extensive sets of drugs with multiple structural variations and known biological activity remains challenging in various biological systems. This work presents novel topological descriptors using Laplacian matrices, weighted, and scaled by atomic mass and partial charges. We tested these descriptors on three sets of GPCR ligands: muscarinic, β-adrenergic, and δ-opioid receptor ligands, evaluating their potential as functional descriptors of these receptors.

TFA-catalyzed solvent-free dearomative cyanidation of isoquinoline using (Boc)2O as an acylation agent

A TFA-catalyzed dearomative cyanidation of isoquinoline is described, which provides a series of 1-cyanoisoquinolines in high yields under solvent-free conditions. This protocol is operated under mild and environmentally friendly conditions, utilizing readily available and cost-effective starting materials. The reaction features broad functional group compatibility, 100 mmol scale synthesis ability and operational simplicity, making it a significant potential approach for the synthesis of various biologically interesting isoquinolines via α C-cyanation.

Exploring the Chiral Match-Mismatch Effect in the Chiral Discrimination of Nitriles

This study tackles the challenge of enantiodifferentiation of nitrile compounds, which is typically difficult to resolve using nuclear magnetic resonance (NMR) due to the significant distance between the chiral center and the nitrogen atom involved in molecular interactions. We have developed novel chiral 19F-labeled probes, each featuring two chiral centers, to exploit the "match-mismatch" effect, thereby enhancing enantiodiscrimination. This strategy effectively differentiates chiral analytes with quaternary chiral carbon centers as well as those with similar substituents at the chiral center. Our approach not only provides a novel method for precise probe performance optimization but also offers a rapid and efficient technique for screening reaction conditions in asymmetric synthesis.

Enantioselective Synthesis of Axially Chiral Allylic Nitriles via Nickel-Catalyzed Desymmetric Cyanation of Biaryl Diallylic Alcohols

Axially chiral nitriles are common motifs in organic photoelectric materials, biological compounds, and agrochemicals. Unfortunately, the limited synthetic approaches to axially chiral nitriles have impeded their availability. Herein, we report the first nickel-catalyzed desymmetric allylic cyanation of biaryl allylic alcohols for the synthesis of axially chiral nitrile structures in high yields with excellent enantioselectivities (up to 90 % yield and >99 % ee). This process enables the synthesis of a diverse range of axially chiral allylic nitriles bearing β,γ-unsaturated alcohol moieties. Leveraging the allylic alcohol and cyano groups as versatile functionalization handles allow for further derivatization of these axially chiral frameworks. Density functional theory (DFT) calculations suggest that both steric and electronic interactions play crucial roles in determining the enantioselectivity of this transformation. Moreover, this mild and facile protocol is also applicable for gram-scale preparation of the chiral nitriles.

Photocatalytic C-C Bond Azidation and Cyanation of Acyclic Ketones via a Pro-aromatic Intermediate

Herein, we report a formal C-C bond azidation and cyanation of unactivated aliphatic ketones using commercially available tosyl azide and cyanide, respectively. A visible-light-mediated organophotocatalyst enables radical azidation and cyanation of ketone-derived pro-aromatic dihydroquinazolinones (under mostly redox-neutral conditions) as supported by preliminary mechanistic studies. These metal-free and scalable protocols can be used to synthesize tertiary, secondary, and primary alkyl azides and nitriles with good functional group tolerance and postsynthetic diversification of the azide group, including bioconjugation.

Targeting QPCTL: An Emerging Therapeutic Opportunity

Glutaminyl cyclases, including glutaminyl-peptide cyclotransferase (QPCT) and glutaminyl-peptide cyclotransferase-like protein (QPCTL), primarily catalyze the cyclization of N-terminal glutamine or glutamate to pyroglutamate (pGlu). QPCTL, in particular, modifies the N-terminus of CD47, thereby regulating its interaction with signal-regulatory protein alpha (SIRPα) and modulating phagocytosis of tumor cells by immune cells. Additionally, QPCTL cyclizes the N-termini of CCL2, CCL7, and CX3CL1, influencing the tumor microenvironment and inflammatory responses in cancer and other disorders. Consequently, QPCTL is considered a valuable therapeutic target for several human diseases. However, the development of QPCTL inhibitors remains in its early stages. This perspective summarizes the structural features, catalytic mechanisms, and biological functions of QPCTL, along with its recent advances in small-molecule inhibitors. It provides valuable insights into the development of novel QPCTL inhibitors.

Ni-catalyzed reductive cyanation of alkenyl tosylates and triflates

Herein, we disclose the nickel-catalyzed reductive cyanation of alkenyl tosylates and triflates. Both cyclic and acyclic alkenyl nitriles are produced in moderate to good yield using 2-(4-methoxyphenyl)-2-methylmalononitrile (MeO-MPMN), a novel transnitrilation, or nitrile transfer, reagent. A robustness screen was undertaken to demonstrate the functional group tolerance of this method.

BrCF2CN for photocatalytic cyanodifluoromethylation

Considering the unique electronic properties of the CF2 and the CN groups, the CF2CN group has significant potential in drug and agrochemical development, as well as material sciences. However, incorporating a CF2CN group remains a considerable challenge. In this work, we disclose a use of bromodifluoroacetonitrile (BrCF2CN), a cost-effective and readily available reagent, as a radical source for cyanodifluoromethylation of alkyl alkenes, aryl alkenes, alkynes, and (hetero)arenes under photocatalytic conditions. This protocol demonstrates an exceptionally broad substrate scope and remarkable tolerance to various functional groups. Notably, the cyanodifluoromethylation of alkynes predominantly provides sterically hindered alkenes, a thermodynamically unfavorable outcome, and (hetero)arene C-H bonds are directly amenable to cyanodifluoromethylation without pre-functionalization.

A Modular Approach for Accessing 3D Heterocycles via 1,2-Dicyanation of Planar N-Heteroarenes

The rapid construction of three-dimensional (3D) heterocyclic frameworks is a key challenge in contemporary medicinal chemistry. The molecules with three-dimensional complexity hold a greater probability to improve clinical outcomes, solubility, selectivity for target proteins, and metabolic stability. However, the prevalence of flat molecules persists among new drug candidates, primarily owing to the multitude of chemical methods available for their synthesis. In principle, the dearomative functionalization of N-heteroarene allows for the conversion of readily available planar molecules into partially or fully saturated nitrogen heterocycles, which are most significant structural motifs of pharmaceuticals and natural products. Unfortunately, these reactions are very rare because of the inherent challenge imposed by heteroarenes' poor reactivity, rendering the process thermodynamically unfavorable. Herein, we report a modular approach for accessing 3D chemical space in translating planar heteroarenes into valuable 3D heterocycles via the installation of a highly versatile cyano group as a new vector. This approach is enabled by the in situ generation of reactive, non-symmetric iodane by combining cyanide anion and bench-stable PhI(OAc)2. This reaction represents a rare example of 1,2-dicyanation of N-heteroarenes that meets the numerous requirements for broad implementation in drug and agrochemical discovery. The transformation is highly selective and amenable to a wide range of N-heteroarenes and late-stage partial saturation of drugs and agrochemicals.

Exploration of small-molecule inhibitors targeting Hsp110 as novel therapeutics

The heat shock protein (HSP) 110 family has a key role as a unique class of molecular chaperones maintaining cellular proteostasis in eukaryotes. Abnormal activation of Hsp110 has been implicated in several diseases. Given its important role in pathogenesis, Hsp110 has become a novel drug target for disease diagnosis and targeted therapy. Thus, targeting Hsp110 or its interactions with client proteins offers new therapeutic approaches. Recent studies of small-molecule inhibitors that target Hsp110 in vitro and in vivo have yielded encouraging results. In this review, we provide an overview of novel therapeutics targeting Hsp110, mainly inhibitors of protein-protein interactions (PPIs), together with a brief discussion of the relevant challenges, opportunities, and future directions.

Hydrogen Bond Blueshifts in Nitrile Vibrational Spectra Are Dictated by Hydrogen Bond Geometry and Dynamics

Vibrational Stark effect (VSE) spectroscopy has become one of the most important experimental approaches to determine the strength of noncovalent, electrostatic interactions in chemistry and biology and to quantify their influence on structure and reactivity. Nitriles (C≡N) have been widely used as VSE probes, but their application has been complicated by an anomalous hydrogen bond (HB) blueshift which is not encompassed within the VSE framework. We present an empirical model describing the anomalous HB blueshift in terms of H-bonding geometry, i.e., as a function of HB distance and angle with respect to the C≡N group. This model is obtained by comparing vibrational observables from density functional theory and electrostatics from the polarizable AMOEBA force field, and it provides a physical explanation for the HB blueshift in terms of underlying multipolar and Pauli repulsion contributions. Additionally, we compare predicted blueshifts with experimental results and find our model provides a useful, direct framework to analyze HB geometry for rigid HBs, such as within proteins or chemical frameworks. In contrast, nitriles in highly dynamic H-bonding environments like protic solvents are no longer a function solely of geometry; this is a consequence of motional narrowing, which we demonstrate by simulating IR spectra. Overall, when HB geometry and dynamics are accounted for, an excellent correlation is found between observed and predicted HB blueshifts. This correlation includes different types of nitriles and HB donors, suggesting that our model is general and can aid in understanding HB blueshifts wherever nitriles can be implemented.

Radical Alkylcyanation of 1,6-Enynes with Isonitriles as Bifunctional Reagents

We report a radical cyano-cyclization of 1,6-enynes with isonitriles via photochemically driven nickel catalysis, forging alkenyl nitrile-tethered γ-lactams under mild conditions. This reaction leverages the photoexcitation of in situ generated nickel (isonitrile) species to facilitate isonitriles serving as alkyl radical precursors and cyanide sources. The reaction accommodates a wide range of substrates, exhibiting excellent regioselectivity and Z/E stereoselectivity.

Asymmetric Hydrogenation of Exocyclic α,β-Unsaturated Nitriles: An Access to Chiral 2-Benzocyclic Acetonitriles and Ramelteon

A highly efficient and enantioselective hydrogenation of exocyclic α,β-unsaturated nitriles catalyzed by the Rh-JosiPhos complex for synthesis of the chiral 2-benzocyclic acetonitriles has been developed. Both (Z)- and (E)-isomers of exocyclic α,β-unsaturated nitriles with various benzocyclic structures, including heterocyclic (chroman and tetrahydroquinoline) scaffolds, were hydrogenated successfully, achieving excellent enantioselectivities (up to 97% ee) and high turnover numbers (TON up to 4000). Furthermore, this methodology provides an efficient, concise, and practical synthetic route to the sleep agent (S)-Ramelteon.

Copper-Catalyzed Asymmetric Tertiary Radical Cyanation for the Synthesis of Chiral Tetrasubstituted Monofluoroacyl Nitriles

The construction of chiral tetrasubstituted α-fluoro-α-cyano carbonyl compounds remains a key challenge in synthetic organic chemistry because of their popularity in multiple disciplines. In this paper, we report the copper-catalyzed asymmetric fluorinated tertiary radical cyanation reaction of cyclic α-iodo-α-fluoroindanones with TMSCN to achieve chiral nitriles with carbon-fluorine quaternary stereogenic centers. Thus, an array of optically active tetrasubstituted monofluoroacyl nitriles were synthesized with high reaction efficiency and excellent enantioselectivities (up to 91% yield, 99% ee). Moreover, mechanistic investigations, including experiments, were conducted to clarify the reaction pathway and stereochemical outcomes.

6-Hydroxy Picolinohydrazides Promoted Cu(I)-Catalyzed Hydroxylation Reaction in Water: Machine-Learning Accelerated Ligands Design and Reaction Optimization

Hydroxylated (hetero)arenes are privileged motifs in natural products, materials, small-molecule pharmaceuticals and serve as versatile intermediates in synthetic organic chemistry. Herein, we report an efficient Cu(I)/6-hydroxy picolinohydrazide-catalyzed hydroxylation reaction of (hetero)aryl halides (Br, Cl) in water. By establishing machine learning (ML) models, the design of ligands and optimization of reaction conditions were effectively accelerated. The N-(1,3-dimethyl-9H- carbazol-9-yl)-6-hydroxypicolinamide (L32, 6-HPA-DMCA) demonstrated high efficiency for (hetero)aryl bromides, promoting hydroxylation reactions with a minimal catalyst loading of 0.01 mol % (100 ppm) at 80 °C to reach 10000 TON; for substrates containing sensitive functional groups, the catalyst loading needs to be increased to 3.0 mol % under near-room temperature conditions. N-(2,7-Di-tert-butyl-9H-carbazol-9-yl)-6-hydroxypicolinamide (L42, 6-HPA-DTBCA) displayed superior reaction activity for chloride substrates, enabling hydroxylation reactions at 100 °C with 2-3 mol % catalyst loading. These represent the state of art for both lowest catalyst loading and temperature in the copper-catalyzed hydroxylation reactions. Furthermore, this method features a sustainable and environmentally friendly solvent system, accommodates a wide range of substrates, and shows potential for developing robust and scalable synthesis processes for key pharmaceutical intermediates.

Divergent Regioselective Synthesis of Functionalized 1,2,3-1H-Triazoles from Nitriles and Arylazides Under Metal-Free and/or Solvent-Free Conditions

Highly selective and divergent syntheses, which are crucial in both organic synthesis and medicinal chemistry, involve significant advancements in compound accessibility. By modifying α-cyano esters into α-cyano ketones, the synthesis pathway broadens to include a diverse range of 4-CN, 5-amino, and 5-arylamino derivatives of 1,2,3-triazoles, which are achieved notably through the Dimroth rearrangement. This versatility extends further with the potential for a triple cascade reaction, leading to the production of carboximidamide compounds, which are facilitated by the Cornforth rearrangement. Advancements in compound accessibility not only expand the repertoire of synthesized molecules but also open new avenues for potential pharmacological agents. Building on these findings, we have developed an innovative and efficient method for the divergent synthesis of functionalized 1,2,3-triazoles. This method strategically utilizes α-cyanocarbonyls and arylazides by harnessing their reactivity and compatibility to orchestrate a variety of molecular transformations. By optimizing these substrates, our goal is to simplify synthetic routes, improve product yields, and accelerate the discovery and development of new chemical entities with promising biological activities.

Copper-Catalyzed Trifunctionalization of Heteroaryl-Substituted 1-Hexenes via Remote Heteroaryl Migration

A copper-catalyzed trifunctionalization (trifluoromethylation, heteroarylation, and cyanation) of heteroaryl-substituted 1-hexenes via remote heteroaryl migration is reported. A variety of CF3 and heteroaryl-containing nitriles were readily constructed under mild conditions. The reaction features high chemo- and regioselectivities and represents a convenient method for the synthesis of multifunctionalized molecules in organic synthesis.

Re-design and evaluation of diclofenac-based carborane-substituted prodrugs and their anti-cancer potential

In this study, we investigated a novel anti-cancer drug design approach by revisiting diclofenac-based carborane-substituted prodrugs. The redesigned compounds combine the robust carborane scaffold with the oxindole framework, resulting in four carborane-derivatized oxindoles and a unique zwitterionic amidine featuring a nido-cluster. We tested the anti-cancer potential of these prodrugs against murine colon adenocarcinoma (MC38), human colorectal carcinoma (HCT116), and human colorectal adenocarcinoma (HT29). The tests showed that diclofenac and the carborane-substituted oxindoles exhibited no cytotoxicity, the dichlorophenyl-substituted oxindole had moderate anti-cancer activity, while with the amidine this effect was strongly potentiated with activity mapping within low micromolar range. Compound 3 abolished the viability of selected colon cancer cell line MC38 preferentially through strong inhibition of cell division and moderate apoptosis accompanied by ROS/RNS depletion. Our findings suggest that carborane-based prodrugs could be a promising direction for new anti-cancer therapies. Inhibition assays for COX-1 and COX-2 revealed that while diclofenac had strong COX inhibition, the re-engineered carborane compounds demonstrated a varied range of anti-cancer effects, probably owing to both, COX inhibition and COX-independent pathways.