Synthesis and biological activities of dithiocarbamates containing 2(5H)-furanone-piperazine

Regioselective Markovnikov hydrothiolation of 1-aryl-1,3-butadienes with dithiocarbamic acid to allyl dithiocarbamates

A metal, ligand and solvent-free three component reaction of 1-aryl-1,3-butadienes, CS2 and amine has been developed. In this process, readily available CS2 and secondary amines were used for C-N and C-S bonds giving allyl dithiocarbamates with notable Markovnikov selectivity, mild reaction conditions, simple operation and compatibility with various functional groups (37 examples). This is first case of dithiocarbamic acid addition to an unsymmetrical 1,3-diene system.

Synthesis and characterization of novel dithiocarbamic thioanhydrides and their application for plant growth stimulant and phytotoxic activity

In this study, nineteen thioanhydrides were synthesized from the S-acylation reaction of sodium dithiocarbamates with various acyl chlorides in chloroform at room temperature. The synthesized thioanhydrides were evaluated for their growth-stimulating and phytotoxic activities. Benzoic (1a), 4-methoxy- (1b), 4-chloro- (1c), 2-bromo- (1e), 4-fluoro- (1f.) and 4-nitrobenzoic 1H-1,2,4-triazole-1-carbothioic thioanhydrides (1 g) showed moderate to excellent growth-stimulating activity, along with this (1c) exhibited excellent phytotoxic activity, 2,4-dichlorobenzoic 1H-1,2,4-triazole-1-carbothioic thioanhydride (1d) and 2,4-dichlorobenzoic pyrrolidine-1-carbothioic thioanhydride (2b) demonstrated inhibiting and moderate phytotoxic activities. Thioanhydrides (1a-c, 1f., 1 g) exhibited excellent germination energy and germination capacity of wheat seeds: 1a 82 and 90%, 1c 80 and 84%, 1 g 82 and 90% (0.01 mg/ml); 1b, 1 g 78 and 94%, 1c 78 and 90%, 1f. 80 and 94% (0.1 mg/ml). Thioanhydride (1e) showed moderate activity, germination energy and germination capacity were 72 and 76% (0.1 mg/ml), 78 and 84% (0.01 mg/ml). Thioanhydride (1d) demonstrated activity as a growth inhibitor with germination energy, and germination capacity 54 and 58% (0.1 mg/ml), 44 and 42% (0.01 mg/ml). Thioanhydride (1c) exhibited excellent phytotoxic activity analogically to herbicide 2,4-D only on lettuce seeds. Compounds (1d and 2b) were moderately active, inhibiting the growth of lettuce and bent grass seedlings.

Photoinduced Decarboxylative Thioacylation of N-Hydroxyphthalimide Esters with Tetraalkylthiuram Disulfides

Dithiocarbamate is a key structural sequence in pharmaceuticals and agrochemicals, and its synthesis is crucial in organic chemistry. Although significant progress has been made in related synthesis research, developing a practical and universal synthesis method remains fascinating. Herein, we report a new visible-light-induced decarboxylation coupling reaction between N-hydroxyphthalimide esters and tetraalkylthiuram disulfides, which uses Ir(ppy)3 as a photocatalyst to promote the generation of corresponding decarboxylation thioacylation product-dithiocarbamates in high yields. This redox-neutral protocol uses inexpensive and readily available starting material under mild reaction conditions, exhibiting broad substrate scope and wide functional group compatibility. This method can be further used for post modification of complex natural products and bioactive drugs.

C3-Alkylation of Imidazo[1,2-a]pyridines via Three-Component Aza-Friedel-Crafts Reaction Catalyzed by Y(OTf)3

As an important class of nitrogen-containing fused heterocyclic compounds, imidazo[1,2-a]pyridines often exhibit significant biological activities, such as analgesic, anticancer, antiosteoporosis, anxiolytic, etc. Using Y(OTf)3 as a Lewis acid catalyst, a simple and efficient method has been developed for the synthesis of C3-alkylated imidazo[1,2-a]pyridines through the three-component aza-Friedel-Crafts reaction of imidazo[1,2-a]pyridines, aldehydes, and amines in the normal air atmosphere without the protection of inert gas and special requirements for anhydrous and anaerobic conditions. A series of imidazo[1,2-a]pyridine derivatives were obtained with moderate to good yields, and their structures were confirmed by 1H NMR, 13C NMR, and HRMS. Furthermore, this conversion has the advantages of simple operation, excellent functional group tolerance, high atomic economy, broad substrate scope, and can achieve gram-level reactions. Notably, this methodology may be conveniently applied to the further design and rapid synthesis of potential biologically active imidazo[1,2-a]pyridines with multifunctional groups.

Facile synthesis of tetrahydroquinoline containing dithiocarbamate derivatives via one-pot sequential multicomponent reaction

An efficient sequential multi-component method for the synthesis of tetrahydroquinoline containing dithiocarbamates has been developed. This reaction involved a boronic acid-catalysed reduction of quinolines to tertrahydroquinolines, followed by nucleophilic addition reaction with carbon disulphide to form dithiocarbamic acids and subsequent S-arylation via external base-free Chan-Evans-Lam coupling in a one-pot operation. The methodology is compatible with a wide variety of functional groups and also useful in the late-stage functionalization of pharmaceuticals. The dual role of the boronic acid as a catalyst (in the reduction of quinolines) and as a reagent (in the S-arylation) has been demonstrated for the first time herein.

Multicomponent Reaction of CS2, Amines, and Sulfoxonium Ylides in Water: Straightforward Access to β-Keto Dithiocarbamates, Thiazolidine-2-thiones, and Thiazole-2-thiones

Simple, versatile, and catalyst-free synthetic methods for β-keto dithiocarbamates, thiazolidine-2-thiones, and thiazole-2-thiones via the multicomponent reaction of CS₂, amines, and sulfoxonium ylides have been described. The β-keto sulfoxonium ylides furnished β-keto dithiocarbamates in the presence of CS₂ and secondary amines, whereas primary amines afforded thiazolidine-2-thiones or thiazole-2-thiones after dehydration in an acidic environment. With simple procedures, the reaction has a wide substrate scope and excellent functional group tolerance.

Development of S-aryl dithiocarbamate derived novel antiproliferative compound exhibiting tubulin bundling

Cancer is a leading cause of human death, and there is a need to identify efficient and novel chemical scaffolds which could provide flexibility to cancer chemotherapeutics. This work introduces S-aryl dithiocarbamates belonging to a versatile group of organo-sulfur containing compounds as a hitherto unexplored class of effective anticancer drugs with promising pharmacophore properties. We synthesized a series of N-Boc piperazine containing S-aryl dithiocarbamates and identified compound 1 as a potent antiproliferative agent in lung, cervical, and breast cancer cell lines. Compound 1 exhibited best inhibitory activity against cervical cancer cells, HeLa with an IC₅₀ of 0.432 ± 0.138 μM for 72 h, and lung cancer cells, A549 with an IC₅₀ of 0.447 ± 0.051 μM for 72 h. We further demonstrate that HeLa cells treated with this compound result in G₂/M phase cell cycle arrest, causing cell apoptosis due to the upregulation of the p53-p21 signaling pathway. Importantly, cells treated with compound 1 showed a novel tubulin bundling phenotype in fluorescence microscopy, which is a characteristic of microtubule-stabilizing anticancer drugs like paclitaxel. Interestingly, molecular docking analysis revealed reasonable binding of compound 1 in the taxol-binding pocket of β-tubulin, making it a promising candidate for microtubule stabilization based anticancer drug discovery.

Synthesis and medicinal chemistry of tetronamides: Promising agrochemicals and antitumoral compounds

Butenolides and tetronic acids occupy a prominent position in synthetic chemistry due to their ubiquitous distribution in nature. This has stimulated investigations firstly in the synthesis of such systems and, laterly, the interest has turned to the understanding of the quantum structure of such systems, allowing a deeper understanding of the mechanism and reactivity of this cyclic scaffold. In contrast, tetronamides, which consist of compounds bearing a 4-aminofuran-2(5H)-one backbone, are relatively rare in nature and synthetic routes to such compounds are poorly explored. This review highlights both the importance of the tetronamide scaffold in medicinal chemistry and the most relevant recondite synthetic strategies for obtaining compounds of this class.

Discovery of 2,4-diarylaminopyrimidine derivatives bearing dithiocarbamate moiety as novel ALK inhibitors

To overcome drug resistance caused by ALK kinase mutations especially G1202R, two series of novel 2,4-diarylaminopyrimidine derivatives bearing dithiocarbamate moiety were designed, synthesized and evaluated for their biological activities. Among all the target compounds, B10 efficiently inhibited the proliferation of ALK-positive Karpas299 and H2228 cells both with IC₅₀ values of 0.07 μM. In addition, B10 exhibited remarkable enzymatic inhibitory potency with IC₅₀ values of 4.59 nM, 2.07 nM and 5.95 nM toward ALK^WT, ALK^L1196M and ALK^G1202R, respectively. Furthermore, B10 induced apoptosis in H2228 cell and caused cell cycle arrest in G2/M phase. Ultimately, the binding modes of B10 with ALK^WT and ALK^G1202R were ideally established, which further confirmed the structural basis in accordance with the SARs analysis. These results indicated that B10 was a potent ALK inhibitor for ALK^G1202R mutation treatment and deserved for further investigation.

Furanonyl amino acid derivatives as hemostatic drugs: design, synthesis and hemostasis performance

Using 3,4-dihalo-2(5H)-furanones and easily available hemostatic drugs, such as tranexamic acid (TA), 4-aminomethylbenzoic acid (ABA), aminocaproic acid (AA) as starting materials, serial multi-functional molecules 2(5H)-furanonyl amino acids are designed by the combination of different pharmacophores, and successfully synthesized by a transition metal-free Michael addition-elimination reaction. The reaction is carried out under mild conditions with ethanol-dichloromethane as solvent and only stirring at room temperature for 24 h, and the yield can be up to 91%. All products are well characterized by infrared spectroscopy (IR), nuclear magnetic resonance (NMR), high-resolution mass spectra (HRMS). Ten typical target compounds among them are selected out for the experiments of hemostasis performance by the evaluation of in vitro clot formation model and liver hemorrhage model. The test results show that, their hemostasis effect is better than the original drugs. Especially the target compound G, a TA derivative from 5-borneoloxy-3,4-dibromo-2(5H)-furanone, has the best hemostasis effect among all the tested compounds. These obtained target molecules are expected to be used as multi-functional hemostatic drugs.

Anticancer and Apoptotic Activity in Cervical Adenocarcinoma HeLa Using Crude Extract of Ganoderma applanatum

Cancer is currently one of the foremost health challenges and a leading cause of death worldwide. Cervical cancer is caused by cofactors, including oral contraceptive use, smoking, multiparity, and HIV infection. One of the major and considerable etiologies is the persistent infection of the oncogenic human papilloma virus. G. applanatum is a valuable medicinal mushroom that has been widely used as a folk medicine for the treatment and prevention of various diseases. In this study, we obtained crude extract from G. applanatum mushroom with a subcritical water extraction method; cell viability assay was carried out and the crude extract showed an antiproliferative effect in HeLa cells with IC₅₀ of 1.55 ± 0.01 mg/mL; however, it did not show any sign of toxicity in HaCaT. Protein expression was detected by Western blot, stability of IκBα and downregulation of NFκB, IKKα, IKKβ, p-NFκB-65(Ser 536) and p-IKKα/β(Ser 176/180), suggesting loss of survival in a dose-dependent manner. RT-qPCR revealed RNA/mRNA expression; fold changes of gene expression in Apaf-1, caspase-3, cytochrome-c, caspase-9, Bax and Bak were increased, which implies apoptosis, and NFκB was decreased in a dose-dependent manner. DNA fragmentation was seen in the treatment groups as compared to the control group using gel electrophoresis. Identification and quantification of compounds were carried out by GC–MS and HPLC, respectively; 2(5H)furanone with IC₅₀ of 1.99 ± 0.01 μg/mL could be the responsible anticancer compound. In conclusion, these findings suggest the potential use of the crude extract of G. applanatum as a natural source with anticancer activity against cervical cancer.

Metal-free visible-light-induced multi-component reactions of α-diazoesters leading to S-alkyl dithiocarbamates

A metal-free and visible-light-promoted strategy has been developed for the synthesis of S-alkyl dithiocarbamates through multicomponent reactions of α-diazoesters, amines and CS2.

Simple inorganic base promoted polycyclic construction using mucohalic acid as a C3 synthon: synthesis and AIE probe application of benzo[4,5]imidazo[1,2-a]pyridines

Using mucohalic acid as C3 synthon via a transition metal-free multicomponent reaction, an eco-friendly protocol to synthesize C1-functionalized benzo[4,5]imidazo[1,2-a]pyridines which can be applied as fluorescence probe for picric acid is described.

Furanone-functionalized benzothiazole derivatives: synthesis, in vitro cytotoxicity, ADME, and molecular docking studies

In the present study, a novel series of new furanone-based benzothiazole derivatives (4a-j) were synthesized from 4-(benzo[d]thiazol-2-yl)-4-oxobutanoic acid (3) as potential anticancer agents. In vitro cytotoxicity against three human cancer cell lines (A549, MCF7, and DUI45) revealed substantial activity. Di-substituted compound, 4i emerged as a promising anticancer compound which showed IC50 values of 7.2 ± 0.5, 6.6 ± 1.4, and 7.3 ± 0.1 µM against A549, MCF7, and DUI45 cell lines, respectively. Four compounds 4c, 4e, 4f, and 4i evaluated for their acute toxicity were found to be non-toxic on the two vital organs (liver and heart). Further, these compounds were found to be more efficient and less hepatotoxic in comparison to standard drug doxorubicin. Molecular docking studies carried out with VEGFR-2 revealed compounds 4a and 4i as potential VEGFR-2 kinase inhibitors. In silico ADME evaluation was carried out to estimate and predict drug-likeness. Compound 4i demonstrated the best ADME parameters. Based on the results of docking analyses, ADME, and in vitro cytotoxicity, compound 4i is identified as the lead compound for further development of anticancer agents.

Multicomponent Synthesis of Biologically Relevant S-Aryl Dithiocarbamates Using Diaryliodonium Salts

A transition-metal-free one-pot three-component annulation between diaryliodonium triflates, cyclic and acyclic aliphatic amines, and carbon disulfide providing a convenient and efficient access to biologically relevant S-aryl dithiocarbamates is developed. The reaction does not require metal, base, or any other additive and operates under mild and ambient conditions. This methodology is robust, scalable, and exhibits a broad substrate scope. The in silico analysis revealed that the majority of the compounds have a drug-likeness and good ADMET characteristics.

Copper-Catalyzed Phosphorylation of 2,3-Allenoic Acids and Phosphine Oxide: Access to Phosphorylated Butenolides

We investigated a novel Cu-catalyzed annulation of 2,3-allenoic acids with diphenylphosphine oxide, leading to the formation of 4-phosphate butenolides in up to 88% yield. The formation of the C-P bond provides new avenues for the functionalization of different furan-2(5H)-ones, with favorable features such as suitable functional group tolerance and mild synthesis conditions.

Synthesis and biological evaluation of novel artemisone-piperazine-tetronamide hybrids

For the first time, six novel artemisone-piperazine-tetronamide hybrids (12a-f) were efficiently synthesised from dihydroartemisinin (DHA) and investigated for their in vitro cytotoxicity against some human cancer cells and benign cells. All the targets showed good cytotoxic activity in vitro. Hybrid 12a exhibited much better inhibitory activity against human liver cancer cell line SMMC-7721 (IC₅₀ = 0.03 ± 0.04 μM for 24 h) than the parent DHA (IC₅₀ > 0.7 μM), and two references, vincristine (VCR; IC₅₀ = 0.27 ± 0.03 μM) & cytosine arabinoside (ARA; IC₅₀ = 0.63 ± 0.04 μM). Furthermore, hybrid 12a had low toxicity against human benign liver cell line LO2 (IC₅₀ = 0.70 ± 0.02 μM for 24 h) compared with VCR, ARA, and DHA in vitro. Moreover, the inhibitory activity of hybrid 12a was obviously enhanced when human liver cancer cell line MHCC97H absorbed Fe²⁺ in vitro.

Synthesis of artemisinin-piperazine-furan ether hybrids and evaluation of in vitro cytotoxic activity

For the first time, eight novel artemisinin-piperazine-furane ether hybrids (5a-h) were efficiently synthesized and investigated for their in vitro cytotoxic activity against some human cancer and benign cells. The absolute configuration of hybrid 5c was determined by X-ray crystallographic analysis. Hybrids 5a-h exhibited more pronounced growth-inhibiting action on hepatocarcinoma cell lines than their parent dihydroartemisinin (DHA) and the reference cytosine arabinoside (ARA). The hybrid 5a showed the best cytotoxic activity against human hepatocarcinoma cells SMMC-7721 (IC₅₀ = 0.26 ± 0.03 μM) after 24 h. Furthermore, hybrid 5a also showed good cytotoxic activity against human breast cancer cells MCF-7 and low cytotoxicity against human breast benign cells MCF-10A in vitro. We found the cytotoxicity of hybrid 5a did not change when tumour cells absorb iron sulfate (FeSO₄); thus, we conclude the anti-tumour mechanism induced by iron ions (Fe²⁺) is unclear.

Synthesis of N-2(5H)-furanonyl sulfonyl hydrazone derivatives and their biological evaluation in vitro and in vivo activity against MCF-7 breast cancer cells

A series of (E)-N-2(5H)-furanonyl sulfonyl hydrazone derivatives have been rationally designed and efficiently synthesized by one-pot reaction with good yields for the first time. This green approach with wide substrate range and good selectivity can be achieved at room temperature in a short time in the presence of metal-free catalyst. The cytotoxic activities against three human cancer cell lines of all newly obtained compounds have been evaluated by MTT assay. Among them, compound 5 k exhibits high cytotoxic activity against MCF-7 human breast cancer cells with an IC₅₀ value of 14.35 μM. The cytotoxic mechanism may involve G2/M phase arrest pathway, which is probably caused by activating DNA damage. Comet test and immunofluorescence results show that compound 5 k can induce DNA damage in time- and dose-dependent manner. Importantly, 5 k also can effectively inhibit the proliferation of MCF-7 cells and angiogenesis in the zebrafish xenograft model. It is potential to further develop N-2(5H)-furanonyl sulfonyl hydrazone derivatives as potent drugs for breast cancer treatment with higher cytotoxic activity by modifying the structure of the compound.

Progress in the Development of Small Molecular Inhibitors of Focal Adhesion Kinase (FAK)

Focal adhesion kinase (FAK) is a nonreceptor intracellular tyrosine kinase that plays an essential role in cancer cell adhesion, survival, proliferation, and migration through both its enzymatic activities and scaffolding functions. Overexpression of FAK has been found in many human cancer cells from different origins, which promotes tumor progression and influences clinical outcomes in different classes of human tumors. Therefore, FAK has been considered as a promising target for small molecule anticancer drug development. Many FAK inhibitors targeting different domains of FAK with various mechanisms of functions have been reported, including kinase domain inhibitors, FERM domain inhibitors, and FAT domain inhibitors. In addition, FAK-targeting PROTACs, which can induce the degradation of FAK, have also been developed. In this Perspective, we summarized the progress in the development of small molecular FAK inhibitors and proposed the perspectives for the future development of agents targeting FAK.

An insight into medicinal attributes of dithiocarbamates: Bird's eye view

Dithiocarbamates are considered as an important motif owing to its extensive biological applications in medicinal chemistry. The synthesis of this framework can easily be achieved via a one-pot reaction of primary/secondary amines, CS₂, and alkyl halides under catalyst-free conditions or sometimes in the presence of a base. By virtue of its colossal pharmacological scope, it has been an evolving subject of interest for many researchers around the world. The present review aims to highlight various synthetic approaches for dithiocarbamates with the major emphasis on medicinal attributes of these architectures as leads in the drug discovery of small molecules such as HDAC inhibitor, lysine-specific demethylase 1 (LSD1) down-regulator, kinase inhibitor (focal adhesion kinase, pyruvate kinase, Bruton's tyrosine kinase), carbonic anhydrase inhibitor, DNA intercalators, and apoptosis-inducing agents. Moreover, recent medicinal advancements in the synthesis of dithiocarbamate derivatives as anticancer, antifungal, antibacterial, anti-Alzheimer, antitubercular, anti-glaucoma, anti-cholinergic, antihyperglycemic, anti-inflammatory activities have been elaborated with notable examples.

Discovery of 2,4-diarylaminopyrimidine derivatives bearing dithiocarbamate moiety as novel FAK inhibitors with antitumor and anti-angiogenesis activities

A series of 2,4-diarylaminopyrimidine derivatives containing dithiocarbamate moiety were designed by molecular hybridization strategy and synthesized for screening as inhibitors of focal adhesion kinase (FAK). Most of these compounds exhibit significant antiproliferative activities on human cancer cell lines expressing high levels of FAK at nanomolar concentrations. The compound 14z was identified as the most potent FAK inhibitor among these candidates. 14z has excellent anti-proliferative effect with IC₅₀ values from 0.001 μM to 0.06 μM on HCT116, PC-3, U87-MG and MCF-7 cell lines and relatively less cytotoxicity to a nonmalignant cell line MCF-10A compared with MCF-7 cells (SI value > 10). 14z also exhibits significant FAK inhibitory activity (IC₅₀ = 0.07 nM). In addition, compound 14z causes cell cycle arrest at G2/M and prompted apoptosis in both HCT116 and MCF-7 cells in a dose-dependent manner. Further studies show that compound 14z inhibits migration of MCF-7 and has anti-angiogenesis effect on HUVEC cells.

Synthesis of amino acid derivatives of 5-alkoxy-3,4-dihalo-2(5H)-furanones and their preliminary bioactivity investigation as linkers

A series of amino acid derivatives are successfully synthesized via a metal-free C-N coupling reaction of 5-alkoxy-3,4-dihalo-2(5H)-furanones and amino acids. Their structures are well characterized with ¹H NMR, ¹³C NMR, ESI-MS and elemental analysis. As potential linkers of the 2(5H)-furanone unit with other drug moieties containing a hydroxyl or amino group, the effect of amino acids is investigated by comparison with other 2(5H)-furanone compounds by constructing C-O/C-S bonds. The preliminary results of the biological activity assay by the MTT method on a series of cancer cell lines in vitro reveal that the introduction of amino acids basically has no toxic effect. This can lead to these 2(5H)-furanone derivatives being further well-linked with other bioactive moieties with amino or hydroxy groups as expected. Thus, the biological activity assay gives a direction for the design of bioactive 2(5H)-furanones based on these amino acid linkers.

Quick construction of a C–N bond from arylsulfonyl hydrazides and Csp2–X compounds promoted by DMAP at room temperature

A mild C–N coupling reaction with arylsulfonyl hydrazides and 2(5H)-furanones shows good yields, excellent reaction regioselectivity and functional group tolerance.