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The multistep synthesis of novel bis-terephthalthioamides based on methyl esters of amino acids (AAs) was proposed using conventional heating and microwave-assisted approaches. In fact, the comparative case study on the thionation of new symmetrical diamides with Lawesson’s reagent (LR) was performed. The microwave-accelerated small-scale methodology was successfully employed on the whole pathway from substrates (Gly, Ala, Val, Tyr, Ser) to products (symmetrical dithioamides of terephthalic acid), resulting in significantly reduced reaction time, energy requirements, and slightly increased reaction yields when compared to conventional heating. Moreover, the intermolecular similarity of novel terephthalic acid derivatives was estimated in the multidimensional space (mDS) of the structure/property-related in silico descriptors using principal component analysis (PCA) and hierarchical clustering analysis (HCA). The distance-oriented structure/property distribution was also correlated with the experimental lipophilic data.

Given their two reactive centers, thioamides serve as useful synthetic building blocks for more complex heterocyclic molecules. The reaction of pyridine-4-thiocarboxamide (1) and pyridine-3-thiocarboxamide (2) with I2 provides protonated forms of the known products 3,5-di-(4-pyridyl)-1,2,4-thiadiazole (1A–1B) and 3,5-di-(3-pyridyl)-1,2,4-thiadiazole (2A–2C), respectively, and yielded new iodide and triiodide salts through the variation of reaction solvent. The analogous reaction of pyridine-2-thiocarboxamide (3) with I2 formed 2,4,6-tris(2-pyridinium)-1,3,5-triazine (3A) instead of a 1,2,4-thiadiazole containing product. The reaction of pyrazine-, pyrimidine-, and 5-methyl-pyridine-2-thiocarboxamide (4–6) in a variety of solvents yielded other heterocyclic products formed from the condensation of two, three, or four thioamide equivalents. Inclusion of bismuth triiodide in these reactions added an additional variable to manipulate, allowing for the further crystallographic study of these organic products. Four common BiI3-derived clusters, [Bi2I9]3−, [Bi4I16]4−, [Bi6I22]4−, and [Bi8I28]4−, were observed alongside these cationic heterocycles. [ABSTRACT FROM AUTHOR]

The cis–trans isomerization of (thio)amides was studied by DFT calculations to get the model for the higher preference for the cis conformation by guided predictive chemistry, suggesting how to select the alkyl/aryl substituents on the C/N atoms that lead to the trans isomer. Multilinear analysis, together with cross-validation analysis, helped to select the best fitting parameters to achieve the energy barriers of the cis to trans interconversion, as well as the relative stability between both isomers. Double experimental check led to the synthesis of the best trans candidate with sterically demanding t-butyl substituents, confirming the utility of predictive chemistry, bridging organic and computational chemistry. [ABSTRACT FROM AUTHOR]

Thioamide‐chelation‐assisted direct Rh(III)‐catalyzed C−H vinylation and Ir(III)‐catalyzed C−H arylation of ferrocenes with vinyl‐ or aryl‐trimethoxysilane under mild and base‐free conditions is described. With thioamide as directing group, various monovinyl and monoaryl substituted thioamideferrocenes were obtained by transition metal‐catalyzed direct C−H functionalization of ferrocenes in 50%‐84% yields with broad substrate range. Mechanistic experiments indicate that C−H bond activation may be the rate‐determining step of the reaction. [ABSTRACT FROM AUTHOR]

In this study, a novel PVC‐based membrane containing (E)‐2‐(1‐(4‐(3‐(4‐chlorophenyl)ureido)phenyl)ethylidene)hydrazine carbothioamide (5) as an electroactive component (ionophore) along with potassium tetrakis (p‐chlorophenyl) borate (KTpClPB) and bis(2‐ethylhexyl)adipate (DEHA) in the ratio 4.0 : 32.0 : 1.0 : 63.0 (ionophore:PVC:KTpClPB:DEHA) (w/w) was used to develop a lead(II)‐selective potentiometric sensor. The sensor exhibited a Nernstian response over a wide concentration range from 1.0×10−5 to 1.0×10−1 mol L−1 with a slope of 28.0±2.0 mV/decade, and a detection limit of 1.65×10−6 mol L−1. It displayed very good selectivity towards Pb(II) ions over other cationic species. The lead(II)‐selective sensor showed a fast response time of 5 s, good repeatability, and it worked in the broad pH range of 5.0–11.0. The sensor could be used as an indicator electrode in the quantification of Pb(II) by potentiometric titration against ethylenediaminetetraacetic acid (EDTA). In addition, this sensor was applied for the direct determination of Pb(II) in different water samples including spring water, purification water, commercial water, waste water and in a waste battery sample. [ABSTRACT FROM AUTHOR]

A family of three‐ and four‐coordinated silver(I) complexes of formulas [Ag(PPh3)2L], [Ag(PPh3)L], and [AgL]n with N‐thiophosphorylated thiourea and thioamide ligands of general formula RC(S)NHP(S)(OPri)2 [R = Ph, PhNH, iPrNH, tBuNH, NH2] have been studied by solid‐state 109Ag and 31P CPMAS NMR spectroscopy. 109Ag NMR spectra have provided valuable structural information about Ag coordination, which is in good accordance with the available crystal structure data. The data presented in this work represent a significant addition to the available 109Ag chemical shifts and chemical shifts anisotropies. The silver chemical shift ranges for different P,S‐environments and coordination state were discussed in detail. The 1J(31P–107/109Ag) and 2J(31P–31P) values were determined and analyzed. [ABSTRACT FROM AUTHOR]

(E)-3-Aryl-2-cyanoprop-2-entioamides, prepared by Knoevenagel condensation between aromatic aldehydes and cyanothioacetamide, react with sodium nitrite in acetic acid to form (2E,2′E)-2,2′-(1,2,4-thiadiazole-3,5-diyl)bis[3-arylacrylonitriles]. A possible mechanism and limitations of the reaction are discussed. Molecular docking was carried out in order to search for possible protein targets for the obtained 1,2,4-thiadiazoles. One of the compounds showed a pronounced antidote effect against the herbicide 2,4-D in a laboratory experiment on sunflower seedlings and under field conditions. [ABSTRACT FROM AUTHOR]

An efficient metal- and additive-free synthesis of α-keto thioamides has been developed via sulfur oxidation of the Csp3–H bond of α-bromo ketones with amines. This environmentally friendly strategy made it possible to synthesize a wide series of α-keto thioamides with broad functional group tolerance. [ABSTRACT FROM AUTHOR]

Amide bond replacement with planar isosteric chalcogen analogues has an important implication for the properties of the N−C(X) linkage in structural chemistry, biochemistry and organic synthesis. Herein, we report the first higher chalcogen derivatives of non‐planar twisted amides. The synthesis of twisted thioamide in a versatile system has been accomplished by direct thionation without cleavage of the σ N−C bond. The synthesis of twisted selenoamide has been accomplished by selenation with Woollins' reagent. The structures of higher chalcogen analogues of non‐planar amides were unambiguously confirmed by X‐ray crystallography. Reactivity studies were conducted to determine the effect of isologous N−C(O) to N−C(X) replacement on the properties of the amide linkage. Computational studies were employed to evaluate structural and energetic parameters of amide bond alteration in higher chalcogen amides. The study provides the first experimental evidence on the effect of chalcogen isologues on the structural and electronic properties of the non‐planar amide N−C(X) linkage. [ABSTRACT FROM AUTHOR]

The current approach involves the kinetic investigation of Thiobenzamide (TB) and cyclohexanone thiosemicarbazone (CTSC) in solution with 3-chloroacetylacetone(3-CAA). The study revealed a second-order rate constant with respect to both reactants, thioamide and an α-halo carbonyl compound. The energy of activation (Ea) was found to be Ea 48.8176kJ/mol/K for thiobenzamide and 33.08692157 kJ/mol/K for Cyclohexanone thiosemicarbazone. The salt effect study showed the formation of ionic species during the reaction. The reactions were studied with respect to changes in dielectric constant using solvent systems like water-ethanol and water-isopropanol. [ABSTRACT FROM AUTHOR]

Direct thionation of quinolizidine alkaloids (-)-cytisine, methylcytisine, thermopsine and some of their carbonyl derivatives was realized. It was established that carrying out of the reaction in the boiling toluene with 0.5 eq. of Lawesson's reagent (LR) is most effective for synthesis of thio analogues of methyl-, allyl-, benzylcytisine and thermopsine. It was found, that formation of thioamides is preferable in the case with starting 3-carboxamides of (-)-cytisine or 2-oxo and 4-oxo derivatives of methylcytisine; and an excess of LR is needed for their exhaustive thionation. It was shown, that thionation of 'cytisine substituted' urea and thiourea, as well as Diels-Alder adducts of methylcitisine with phenylmaleimide on basis of this approach was not quite successful: only thionation of the 2-pyridone core has occurred. It should be noted that transformation of urea and thiourea is complicated by side reactions leading to low yields of thio products, and the result of LR interaction with mentioned above diastereomeric Diels-Alder adducts depends on their stereochemistry and thermodynamic stability under reaction conditions. [ABSTRACT FROM AUTHOR]

The potential of industrial cobalt phthalocyanines in the synthesis of thioamides is reported. A mixture of an industrial sulfonated cobalt phthalocyanines known as Co[(SO3Na)2,3Pc] (Europhtal catalyst additive 8020) is introduced as an efficient catalyst capable of converting benzyl thiols to synthetically valuable thioamides by reaction with amines and DMSO. In this procedure, different primary and secondary amines also heterocyclic amines were successfully converted into benzothioamides in high yields. This simple, one‐pot three‐component conversion method is scalable and provides efficient and practical route to the synthesis of diverse benzothioamides. [ABSTRACT FROM AUTHOR]

Osmium(IV) pyrazole carbothioamide complexes with different substituted pyrazole carbothioamide heterocyclic ligands have been synthesized and characterized. The ligands have been characterized using 1H-NMR, 13C-APT, LC-MS, elemental analysis, and IR spectroscopy. Whereas, osmium(IV) compounds have been characterized using ESI-MS, ICP-OES, IR spectroscopy, magnetic, and conductance measurements. The compounds have been evaluated for various biological activities. The binding constant of ligands and complexes have been found in the range of 1.2–3.6 × 104 and 1.2–6.8 × 104 M−1, respectively. The docking energy values of complexes have been found in the range of −286.28 to −326.49 kJ/mol. The Ksv and Kf values of Os(IV) compounds evaluated using fluorescence quenching activity have been found in the range of 4.7–9.2 × 103 and 1.3–7.6 × 103 M−1, respectively. The minimum inhibitory concentration of osmium(IV) compounds and ligands have been found in the range of 50–75 µM and 120–135 µM, respectively. The LC50 values evaluated using brine shrimp lethality assay of osmium(IV) compounds and ligands have been found in a range of 7.52–16.12 µg/mL and 15.80–20.03 µg/mL, respectively. [ABSTRACT FROM AUTHOR]

Realizing the precise structure design and functional customization of photocatalysts is essential for achieving high conversion and selectivity. Herein, we propose an innovative pore space partition strategy for constructing a high-performance photocatalyst from a single ligand by regulating the group modification and symmetry of the ligand, which solves the problem of open-metal sites occupation. A novel polyoxometalate-based metal-organic framework, CoW – BTIz , was synthesized successfully from a new donor-acceptor-donor type photosensitizer 4, 7-bis (imidazolyl) benzothiazole, Co cations and electron sponge [BW 12 O 40 ]5– anions. The push−pull effect of the D–A–D units in the confined spatial ensures the charge rapid transport processes. Incorporating POM into photoactive MOF is beneficial to produce single •O 2 – via type I pathway primarily in air atmosphere by photogenerated electron transfer. CoW–BTIz gave a high yield in the aerobic synthesis of 2-arylbenzothiazole and the cyclization of thioamide to 1,2, 4-thiadiazole by the synergetic effect of each component in mild conditions. [Display omitted] ● An innovative PSP strategy was developed for constructing a high-performance photocatalyst from a single ligand. ● Introducing of D–A–D type photosensitizer BTIz into CoW–BTIz solves the problem of OMS occupation. ● The push−pull effect of the D–A–D units in the confined spatial of CoW–BTIz ensures the charge rapid transport processes. ● Incorporating POM into photoactive MOF is beneficial to produce single •O 2 – via type I pathway in air atmosphere by PET. ● CoW–BTIz gave high yields in the aerobic synthesis of 2-aryl benzothiazole and 1,2,4-thiadiazole. [ABSTRACT FROM AUTHOR]

• In-situ boron-fluorine functionalized sulfur-doped graphitic carbon nitride (BFx-SGCN) as a multifunctional heterogeneous synergistic photocatalyst for cyclization reactions along with cofactor regeneration engineering. • Modification of SGCN where boron (B) and fluorine (F) atoms are intentionally introduced or vacancies of these atoms are created within the SGCN structure. • The current research work provides a benchmark example of a BF1.0-SGCN photocatalyst for NADH regeneration cofactor with excellent yield (73.47 %) and triggered synthesis of 3,5-diphenyl 1,2,4-thiadiazole derivatives via N-S bond activation with high yield 94 % under ambient conditions. • The goal of the research is to investigate how the photocatalyst's constituent parts can work together to improve performance in certain applications. In-situ boron-fluorine functionalized sulfur-doped graphitic carbon nitride (BF x -SGCN, x = 1, 1.5, and 2.0 ml) as a multifunctional heterogeneous synergistic photocatalyst for the cyclization reactions and cofactor regeneration engineering. This refers to a modification of SGCN where boron (B) and fluorine (F) atoms are intentionally introduced, or vacancies of these atoms are created within the SGCN structure. This modification is likely aimed at altering the electronic properties and surface chemistry of SGCN to enhance its photocatalytic activity. It was verified that the numerous active sites and enhanced BF vacancies worked in concert to improve the band gap, photoinduced carrier carriers, and visible light absorption efficiency. In this context, the current research work provides a benchmark example of a BF 1 -SGCN photocatalyst for NADH regeneration with excellent yield (73.47 %) in 90 minutes and triggered oxidative cyclization of aromatic primary thioamides (synthesis of 3,5-diphenyl 1,2,4-thiadiazole derivatives) via N-S bond activation with high yield 94 % in 6 hours under ambient conditions. The goal of the research is to investigate how the photocatalyst's constituent parts can work together to improve performance in certain applications. [Display omitted] [ABSTRACT FROM AUTHOR]

• Macrocycle 1 and its thioamide analogue 2 were structurally confirmed by X-ray diffraction method. • Significantly different anion-binding properties were seen between two macrocycles. • Macrocycle 1 also formed a 1:1 complex with PhCOO− ion in the solid state. An easy-to-prepare 1,8-disulfonamidocarbazole-diamide hybrid macrocycle 1 and its thioamide analogue 2 were reported, along with their anion recognition properties as determined by UV–vis and 1H NMR spectroscopic titrations as well as single crystal X-ray diffraction analyses. The conversion of amides into thioamides in the macrocyclic structures generated notable effects on the anion-binding affinity and selectivity. For example, amide-bearing macrocycle 1 was found to bind H 2 PO 4 - over one order of magnitude more strongly than thioamide-containing macrocycle 2 , despite having more acidic NH groups for the latter. Additionally, macrocycle 1 displayed the highest affinity for PhCOO- in DMSO (K a >105 M-1 for the formed 1:1 complex) followed by H 2 PO 4 - and AcO- ions, whereas a different binding order AcO- > PhCOO- >> H 2 PO 4 - was observed for macrocycle 2. More importantly, the single crystal X-ray diffraction analysis clearly revealed that macrocycle 1 indeed formed a 1:1 complex with PhCOO- ion in the solid state. Macrocycle 1 displayed a strong affinity for PhCOO- ion in DMSO solution (K a >105 M-1 for the formed 1:1 host-guest complex, as determined by UV–vis titration spectroscopy), and the above binding ratio was also confirmed by X-ray crystallography. [Display omitted] [ABSTRACT FROM AUTHOR]

• Synthesis and characterization of hydrazine carbothioamide derivatives through a condensation reaction. • Probe L (Compound 5 a) shows good intensity compared to other derivatives (Compound 5 b and 5 c). • Absorbance and emission spectra of L probe at 309 nm and 425 nm respectively. Probe L showed an exceptional ability to recognize and bind with cyanide ions, a toxic environmental chemical, with significant photophysical properties. • Confirmation of binding stoichiometry (1:1) through various analytical methods including Job's and HRMS spectroscopy. Determination of a relatively low limit of detection for cyanide ions (0.635 µM). • For practical application, probe L was investigated through the test strips and detection of cyanide in diverse water samples and food samples. This study reports the synthesis of various hydrazine carbothioamide derivatives through a Schiff base reaction, confirmed by FT-IR, NMR (1H and 13C), and HRMS spectroscopic methods. Among the synthesized derivatives, probe L ((4-fluorobenzylidene)-2-(1-phenylethylidene)hydrazine-1-carbothioamide) was identified as a highly selective fluorometric chemosensor based on its absorbance and emission spectra. Probe L showed a CN− ion-specific turn-on fluorescence response, with very little interference from other anions. Job's method established a 1:1 binding stoichiometry among probe L and the cyanide ion. The detection limits (LOD) and quantification (LOQ) were observed to be 0.639 µM and 2.116 µM, respectively. With the use of FT-IR spectroscopy, 1H NMR titration, 13C NMR and HRMS, the binding mechanism was clarified. Moreover, probe L was employed effectively for detecting CN− ions in water and food samples, highlighting its potential as a practical sensor for cyanide detection. [Display omitted] [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Synthesis of novel carbazole hydrazine-carbothioamide scaffold as potent antioxidant, anticancer and antimicrobial agents" published in BMC Chemistry. The correction addresses an affiliation error in the supplementary material and states that it has been replaced with the correct file. The original article has been corrected. The document also includes the names of the authors involved in the study. [Extracted from the article]

[Display omitted] • New derivatives of tropane scaffold were synthesized and examined for their cytotoxic effect. • The most active compounds 3, 4, 5, 9d and 14a displayed significant antitumor activities with IC 50 range of 9.50 – 30.15 μM. • Compound 3 was found to be the most potent Hsp90 inhibitor with IC 50 value of 56.58 ± 0.86 nM. • The Western blotting assay for the tested derivatives revealed a significant inhibition of Hsp90. • A molecular modeling study of the active derivatives was done where they have good binding affinities to Hsp90 via the key residues. New derivatives of tropane scaffold were prepared from the reaction of their thione or thioamide derivatives with α-halocarbonyl compounds. The structures of all new derivatives were assured and proved with their spectral data. The novel tropane derivatives were examined for their cytotoxicity on two colon tumor cell lines; Caco2 and HCT116 cells. The most active compounds 3 , 4 , 5 , 9d and 14a displayed significant antitumor activities with IC 50 range of 9.50 – 30.15 μM compared to doxorubicin. Moreover, they revealed reduced cytotoxic effect on WI‐38 normal ones, signifying their great safety. With the aim of better understanding the inhibitory potential of such compounds on heat-shock protein 90 (Hsp90), there activities were assessed against such enzyme demonstrating high inhibitory activities with IC 50 range of 56.58–78.85 nM. Western blotting was carried out to ensure the inhibitory activity on Hsp90, results showed that 3 markedly suppressed Hsp90 expression on Caco2 cell line. Additionally, a molecular docking analysis of the most potent derivatives at the Hsp90 binding site was carried out in order to approve the performed in vitro assays. [ABSTRACT FROM AUTHOR]

Malaria continues to be a significant burden, particularly in Africa, which accounts for 95% of malaria deaths worldwide. Despite advances in malaria treatments, malaria eradication is hampered by insecticide and antimalarial drug resistance. Consequently, the need to discover new antimalarial lead compounds remains urgent. To help address this need, we evaluated the antiplasmodial activity of twenty-two amides and thioamides with pyridine cores and their non-pyridine analogues. Twelve of these compounds showed in vitro anti-proliferative activity against the intraerythrocytic stage of Plasmodium falciparum , the most virulent species of Plasmodium infecting humans. Thiopicolinamide 13i was found to possess submicromolar activity (IC 50 = 142 nM) and was >88-fold less active against a human cell line. The compound was equally effective against chloroquine-sensitive and -resistant parasites and did not inhibit β-hematin formation, pH regulation or Pf ATP4. Compound 13i may therefore possess a novel mechanism of action. [Display omitted] • Synthesis of 22 compounds including pyridine carboxamides, thioamides and their non-pyridine analogues. • Synthesized compounds were evaluated for antiplasmodial activity. • Salt formation and reduction of the pyridine ring increased antiplasmodial activity. • Thiopicolinamide 13i displayed potent antiplasmodial activity and low toxicity. • The mechanism of action of 13i is not due to inhibition of hemozoin formation. [ABSTRACT FROM AUTHOR]

In recent years, there has been an increasing interest in the study of Ag(I) coordination compounds as potent antibacterial and anticancer agents. Herein, a series of Ag(I) complexes bearing phosphines and heterocyclic thioamide ligands with highly electronegative NH2- and CF3-group substituents, i.e. [AgCl(atdztH)(xantphos)] (1), [Ag(μ-atdztH)(DPEphos)]2(NO3)2 (2), [Ag(atdzt)(PPh3)3] (3), [Ag(μ-atdzt)(DPEphos)]2 (4), and [Ag(μ-mtft)(DPEphos)]2 (5), where atdztH = 5-amino-1,3,4-thiadiazole-2-thiol, mtftH = 4-methyl-5-(trifluoromethyl)-1,2,4-triazol-3-thiol, xantphos = 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene, and DPEphos = bis(2-diphenylphosphino-phenyl)ether, were synthesized, and their in vitro antibacterial and anticancer properties were evaluated. Complexes 1–4 bearing the NH2-substituted thioamide exhibited moderate-to-high activity against S. aureus, B. subtilis, B. cereus and E. coli bacterial strains. A high antiproliferative activity was also observed for 1–3 against SKOV-3, Hup-T3, DMS114 and PC3 cancer cell lines (IC50 = 4.0–11.7 μM), as well as some degree of selectivity against MRC-5 normal cells. Interestingly, 5 bearing the CF3-substituted thioamide is completely inactive in all bioactivity studies. Binding of 1–3 to drug-carrier proteins BSA and HSA is reasonably strong for their uptake and subsequent release to possible target sites. The three complexes show a significant in vitro antioxidant ability for scavenging free radicals, suggesting likely implication of this property in the mechanism of their bioactivity, but a low potential to destroy the double-strand structure of CT-DNA by intercalation. Complementary insights into possible bioactivity mechanisms were provided by molecular docking calculations, exploring the ability of complexes to bind to bacterial DNA gyrase, and to the overexpressed in the aforementioned cancer cells Fibroblast Growth Factor Receptor 1, affecting their functionalities. [ABSTRACT FROM AUTHOR]

The amino groups of thio‐ and selenoamides can act as stronger hydrogen‐bond donors than of carboxamides, despite the lower electronegativity of S and Se. This phenomenon has been experimentally explored, particularly in organocatalysis, but a sound electronic explanation is lacking. Our quantum chemical investigations show that the NH2 groups in thio‐ and selenoamides are more positively charged than in carboxamides. This originates from the larger electronic density flow from the nitrogen lone pair of the NH2 group towards the lower‐lying π*C=S and π*C=Se orbitals than to the high‐lying π*C=O orbital. The relative energies of the π* orbitals result from the overlap between the chalcogen np and carbon 2p atomic orbitals, which is set by the carbon‐chalcogen equilibrium distance, a consequence of the Pauli repulsion between the two bonded atoms. Thus, neither the electronegativity nor the often‐suggested polarizability but the steric size of the chalcogen atom determines the amide's hydrogen‐bond donor capability. [ABSTRACT FROM AUTHOR]

The paper is focusing on the amide linkage exceptional properties and usage of chemistry (conformational rearrangement, geometrical stereoisomers, spectroscopic blue shift phenomenon, protonation and deprotonation reactions, synthetic scope, and mechanistic implications). Hydrogen-bond-stabilized acylation reactions of a diamine with thioamides or nitriles reveal how substituents influence both the outcome of stereoselectivity and interactions. Inferring the chemical mechanism from the structures of reactants is dissimilar to the appropriate E isomers, the Z form becomes more favored in the secondary amides obtained. One conclusion from the estimation of Z structures, based on the 1H-15N 2D NMR spectra in comparison with the references, is the existence of the intramolecular, blue shifting CON−H...+NH2CH3 hydrogen bonds. The rearrangement of a methylamino residue provided the free base stabilized in the CH3N−H...O=CNH after deprotonation. An essential part of the publication describes systems in a highly stereoselective fashion, so the stereochemical outcome of the product is predictable now. [ABSTRACT FROM AUTHOR]

Thioamides represent highly valuable isosteric in the strictest sense "single‐atom substitution" analogues of amides that have found broad applications in chemistry and biology. A long‐standing challenge is the direct transamidation of thioamides, a process which would convert one thioamide bond (R−C(S)−NR1R2) into another (R−C(S)−NR3N4). Herein, we report the first general method for the direct transamidation of thioamides by highly chemoselective N−C(S) transacylation. The method relies on site‐selective N‐tert‐butoxycarbonyl activation of 2° and 1° thioamides, resulting in ground‐state‐destabilization of thioamides, thus enabling to rationally manipulate nucleophilic addition to the thioamide bond. This method showcases a remarkably broad scope including late‐stage functionalization (>100 examples). We further present extensive DFT studies that provide insight into the chemoselectivity and provide guidelines for the development of transamidation methods of the thioamide bond. [ABSTRACT FROM AUTHOR]

A highly modular method for the synthesis of (Z)-3-[amino(phenyl/methyl)methylidene]-1,3-dihydro-2H-indol-2-ones starting from easily available 3-bromooxindoles or (2-oxoindolin-3-yl)triflate and thioacetamides or thiobenzamides is described. A series of 49 compounds, several of which have previously been shown to possess significant tyrosin kinase inhibiting activity, was prepared in yields varying mostly from 70 to 97% and always surpassing those obtained by other published methods. The method includes an Eschenmoser coupling reaction, which is very feasible (even without using a thiophile except tertiary amides) and scalable. The (Z)-configuration of all products was confirmed by NMR techniques.

An efficient and versatile copper-catalyzed intermolecular radical [3+2] annulation of thioamides with azobisisobutyronitrile (AIBN) is described. This two-component copper(II)-catalyzed transformation is achieved in one pot via cascade formation of C–S/C–N bonds through cyclization of an in situ generated N , S -acetal intermediate derived from a β-ketothioamide. This operationally simple method allows direct access to synthetically demanding thiazolidin-4-ones in good to excellent yields containing diverse functional groups of different electronic and steric nature. The readily available reaction partners, the avoidance of expensive/toxic reagents and a gram-scale synthesis are additional attributes of this strategy. AIBN plays a dual role as a radical initiator and an unusual source of a two-carbon coupling partner. Notably, the products possess Z stereochemistry with regard to the exo-cyclic C=C double bond at position 2 of the thiazolidine ring. [ABSTRACT FROM AUTHOR]

The molecular mechanism of sudoxicam and meloxicam metabolism to thioamide is clarified based on the results of quantum chemistry calculations. The two drugs are first activated to generate carbonyl intermediate 5‐PC. When the reaction site is on C5 of the thiazole ring, 5‐PC is directly obtained; when the reaction site is on C4, metabolite epoxide is easily isomerized to give 5‐PC instead of hydrolysis to glycols. 5‐PC is an important intermediate, which is further metabolized to generate thioamide. The molecular docking experiments clarify the reasons for the difference in hepatotoxicity of two drugs caused by methyl groups. Compared with close distance between Fe and the thiazole ring in sudoxicam, the additional methyl group in meloxicam is more close to the Fe(III)‐heme moiety, which suppresses the bioactivation of the thiazole ring. The position of methyl binding in the cytochrome P450 pocket determines the activation difference of thiazole in meloxicam and sudoxicam. The study provides detailed molecular mechanisms for the differences in metabolism and toxicity of the two drugs and lays the foundations for drug design and drug modification. [ABSTRACT FROM AUTHOR]

Synthesis and inhibition effectiveness of (2E)-2-(furan-2-ylmethylidene) hydrazine carbothioamide (FMHC) as an inhibitor for corrosion of mild steel in 0.5 M H2SO4 is reported. Experiments were conducted at various temperatures (303–323 K) by adopting potentiodynamic polarization and electrochemical impedance spectroscopy. Readings obtained demonstrated that percentage inhibition efficiency (% IE) improved with the upsurge in the concentration of FMHC, while it decreased with a rise in temperature. The highest % IE observed was 60% for 2.5 × 10–4 M FMHC at 303 K. FMHC worked moderately as a mixed inhibitor. FMHC obeyed the Langmuir model of adsorption and the mode of adsorption was physisorption on the mild steel surface which was further endorsed by examining the surface using the scanning electron microscope. A clear insight into the mechanistic features of corrosion inhibition by using FMHC was acquired. Calculation of activation parameters helped to suggest an appropriate mechanism for the adsorption of FMHC on mild steel through quantum chemical calculations using density functional theory (DFT). [ABSTRACT FROM AUTHOR]

[Display omitted] Eco-friendly synthesis of organic compounds is a major trend in green chemistry. Thus, we aim at producing some of the lube oil additives through the use of green chemistry. Dispersant lube oil additives are remarkable additives that regulate the formation of deposits throughout the process. Antioxidants do not prevent the oxidation reactions but only delay the rate of this process. In the present work, some additives for lube oil based on thiourea derivative were prepared by one-step reaction, which is the reaction of octadeca-7-enoy) chloride with ammonium thiocyanate in addition to different amines such as ethylenediamine, diethylene triamine, and tetraethylene pentamine as three-component system in order to prepare thioamide derivatives (A, B, and C). Infrared spectroscopy, elemental analysis, nuclear magnetic resonance, determination of molecular weights, and yield determination verified the chemical structure of all synthesized molecules. All the compounds produced are tested as lube oil additives (dispersants and antioxidants), and it has been found that all the compounds prepared are good as dispersants but have poor effect as antioxidants. The theoretical result is the same as the experimental result of antioxidants through the use of the quantum chemical calculations by calculating the energy gap (EHOMO-ELUMO). The best dispersant lube oil additive is (C). [ABSTRACT FROM AUTHOR]

The chemical and physiological stability of tetrazole motifs, as well as their broad range of medicinal properties, have been intensively investigated. But still, scientific community uses the best efforts to develop structurally different variations of substituted tetrazoles to investigate their potential applications. In this review, various methods applying combinations of different reagents such as SiCl4/NaN3, PCl5/N2H4/N2O4, PPh3/DEAD/TMSN3, NaN3/HgCl2, and DPPA/DIAD for the selective synthesis of 1,5-disubstituted tetrazoles converting amide and thioamide functionalities have been described. This approach of thioamide and amide replacement allows to introduce tetrazole as isosteric substituent increasing metabolic stability of biologically active compounds. [ABSTRACT FROM AUTHOR]

Molecular and crystal structures of two octahedral zinc complexes with chelated N-phosphorylated thiobenzamide ligands and nitrogen bidentate aromatic ligands (bipyridyl and phenanthroline) are determined by XRD. It is shown that the zinc atom in the complexes with thiobenzamide ligands is coordinated (in contrast to the complex with an amino group at the carbon atom of the thiacarbamate ligand) by sulfur and oxygen atoms of thiocarbonyl and phosphoryl groups to form six-membered metallacycles. [ABSTRACT FROM AUTHOR]

In this article, we present an efficient, one-pot regioselective approach towards the synthesis of 2-aryl/hetaryl-4-methyl-5-acylthiazoles obtained during the reaction of α-bromo-1,3-diketones generated in situ by triturating unsymmetrical 1,3-diketones with N-bromosuccinimide, with various thioamides under solvent-free conditions. This environmentally benign protocol showed large functional group tolerance, resulted in the exclusive formation of a single isomer, out of the two possible regioisomers in admirable yields. The structure of the isomeric thiazole was assigned unambiguously on the basis of multinuclear NMR [(1H-13C) HMBC, (1H-13C) HMQC, (1H-15N) HMBC] and X-ray crystallographic studies. The entire protocol is ecologically desirable as it employs no organic solvent. [ABSTRACT FROM AUTHOR]

A simple, expedited, and eco-friendly protocol for the synthesis of thioesters and thioamides using Potassium thiocyanate as thionating agent under microwave irradiation method is described. Synthesized compounds are obtained in good yield were analyzed by spectral techniques and matching with the standard compounds made by the reported procedure. [ABSTRACT FROM AUTHOR]

A new series of thiazole nortopsentin analogues with a 5-azaindole moiety was conveniently synthesized in good to excellent yields by an Hantzsch reaction between thioamides and a-bromoacetyl compounds. The cytotoxic activity of the new derivatives was tested against different human tumor cell lines of the NCI full panel. All tested compounds were active against all of the investigated cell lines showing GI50 values from micro to submicromolar levels. Some of the new analogues exhibited good selectivities against different NCI sub-panels. [ABSTRACT FROM AUTHOR]

N-Sulfonyl amidines bearing 1,2,3-triazole, isoxazole, thiazole and pyridine substituents were successfully prepared for the first time by reactions of primary, secondary and tertiary heterocyclic thioamides with alkyl- and arylsulfonyl azides. For each type of thioamides a reliable procedure to prepare N-sulfonyl amidines in good yields was found. Reactions of 1-aryl-1,2,3-triazole-4-carbothioamides with azides were shown to be accompanied with a Dimroth rearrangement to form 1-unsubstituted 5-arylamino-1,2,3-triazole-4-N-sulfonylcarbimidamides. 2,5-Dithiocarbamoylpyridine reacts with sulfonyl azides to form a pyridine bearing two sulfonyl amidine groups.

Thioamides are widely used structures in pharmaceuticals and agrochemicals, as well as important synthons for the construction of sulfur-containing heterocycles. This report presents a series of visible-light-driven multicomponent reactions of amines, carbon disulfide, and olefins for the mild and versatile synthesis of linear thioamides and cyclic thiolactams. The use of inexpensive and readily available carbon disulfide as the thiocarbonyl source in a radical pathway enables the facile assembly of structurally diverse amine moieties with non-nucleophilic carbon-based reaction partners. Radical thiocarbamoylative cyclization provides a practical protocol that complements traditional approaches to thiolactams relying on deoxythionation. Mechanistic studies reveal that direct photoexcitation of in situ formed dithiocarbamate anions as well as versatile photoinduced electron transfer with diverse electron acceptors are key to the reactions., (© 2024 Wiley-VCH GmbH.)

A set of novels 2-thiohydantoin derivatives were synthesized and enaminone function was discussed at position 5 using DMFDMA catalyst which result in formation of pyrazole, isoxazole, benzoxazepine by using reagents such as hydrazine, hydroxylamine and 2-aminothiophenol. These newly synthesized compounds were evaluated for their antioxidant and antiproliferative activity. In vitro studies on the effect of 2-thiohydantoin on scavenging 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) confirmed the free radical scavenging and antioxidant activity of 2-thiohydantoin. The synthesized compounds show significant antioxidant activity. The in vitro antitumor activity of 2-thiohydantoin on MCF7 (breast) and PC3 cells (prostate) was evaluated using MTT assay. Some of the synthesized compounds show significant to moderate antiproliferative properties compared to reference drug erlotinib. Among all, compound 4a exhibit potent antitumor properties against MCF7 and PC3 cancer cell lines with IC 50  = 2.53 ± 0.09 /ml & with IC 50  = 3.25 ± 0.12 µg/ml respectively and has potent antioxidant activity with IC 50  = 10.04 ± 0.49 µg/ml., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The reactions of 4,5-diaroyl-1H-pyrrole-2,3-diones with thiosemicarbazide and semicarbazide in-volved elimination of carbothioamide or carboxamide group and afforded substituted 3,4-diaroyl-1H-pyrazole-5-carboxamides. This reaction provides a convenient preparative route to 1H-pyrazole-5-carboxamides that attract interest for medicinal chemistry. [ABSTRACT FROM AUTHOR]

A general and clean method for the one‐pot synthesis of thioamides was investigated using a combination of experiments and quantum chemical calculations. Ester, amide, and elemental sulfur were employed as starting materials and ethylene diamine tetraacetic acid (EDTA) as catalyst. Both alkyl and aryl thioamides with various functional groups were obtained in moderate to good yields. Neither transition metals nor external oxidants were required in this reaction. The catalytic performance of EDTA originates from a stepwise, proton transfer process in which EDTA transports a proton from the benzyl carbon to a sulfur atom. Such a process is concerted by discrete charge transfer such that the associated barrier gets lowered. [ABSTRACT FROM AUTHOR]