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This research aims to create innovative compounds that incorporate 1,2,4‐triazole and exhibit α‐glucosidase inhibitory potential. Similar to our previously reported series of N‐aryl 2‐{[5‐(naphthalen‐1‐ylmethyl)‐4‐phenyl‐4H‐1,2,4‐triazol‐3‐yl]thio}acetamide compounds, we explore here 4‐ethyl instead of 4‐phenyl as substituent. The synthesis process effectively yielded these compounds, with the highest yield reaching up to 91 % for compound N‐phenyl‐2‐{[5‐(naphthalen‐1‐ylmethyl)‐4‐ethyl‐4H‐1,2,4‐triazol‐3‐yl]thio}acetamide 5 a. Their structures were validated through various spectroscopic techniques such as IR, 1H‐NMR, 13C‐NMR, and HR‐MS spectra, and for compounds 3, 5 d, and 5 e by X‐ray diffraction. In vitro experiments revealed that only compound 5 g, marked by a 3‐hydroxy substitution on the N‐phenylacetamide moiety, demonstrated higher α‐glucosidase inhibitory potential (IC50=158.4±3.4 μM) compared to the positive control, acarbose (IC50=351.3±1.8 μM). Molecular docking studies also coincide with in vitro assay by uncovering a strong hydrogen bond with residue Asp1526 along with other hydrophobic interactions of compound 5 g in the α‐glucosidase binding pocket. Compound 5 g showed a free binding energy of −9.7 kcal/mol, contrasting with acarbose (−8.0 kcal/mol). Despite the modest biological activity, this research underscores the simplicity and convenience of the procedure for synthesizing 1,2,4‐triazole‐based compounds, and contributes a key feature to the structure‐activity relationship of the triazole scaffold in the α‐glucosidase pocket. [ABSTRACT FROM AUTHOR]

Methyl 4-(1,3a,6a-triazapentalen-3-yl)benzoate (TAP1) shows interesting properties as a small molecule fluorophore. In the search for post-functionalization methods, palladium-catalyzed arylation reactions were demonstrated. Direct CH arylation reactions of TAP1 with various aryl halides resulted in 3,6-diaryltriazapentalenes TAP4, although mostly in poor yields. Bromination of TAP1 followed by Suzuki coupling, on the other hand, requires a more delicate procedure, but gave arylated products with the same regiochemistry (TAP4) in moderate to good yields. The structure of 6-phenyltriazapentalene TAP4a was confirmed by crystallographic analysis. In addition, the effect of the C6 arylation on the fluorescent properties of 3-aryl-1,3a,6a-triazapentalenes was studied in dichloromethane at room temperature and in 2-methyltetrahydrofuran at 77 K, while the photophysical properties of two saponified derivatives were measured in acetonitrile. [ABSTRACT FROM AUTHOR]

para-Aminobenzoic acid (p-ABA) is a pharmaceutical compound with a challenging polymorph nucleation behavior. It has 4 polymorphs and multiple solvates. Among these forms, the α and the β form are subjects of interest for research in many studies. The α form nucleates predominantly in many solvents. The β form is known to nucleate in only 2 solvents. The reasoning for this was that the solvents, having a strong interaction with the COOH group, inhibit the dimerization of the COOH group leading to the nucleation of the β form. Following this reasoning, in this work, DMSO and DMF, which have strong interaction with the COOH group, were tested as solvents for anti-solvent crystallization experiments. Water was used as anti-solvent. The goal was to investigate the resultant polymorph nucleation under such specific solvent–solute interaction. Results showed that with DMSO as solvent at higher anti-solvent volume fraction the α form nucleated predominantly. At lower volume fractions there was no nucleation normally but addition of some seeds quickly led to β form nucleation. With DMF, a special result was seen where a new solvate between p-ABA and DMF was discovered. Single crystal XRD results confirmed that the formation of the solvate was a result of hydrogen bonding between the solute and the solvent. Overall, the results do confirm that solvents having strong interaction with the COOH group can lead to nucleation of forms other than the persistent form. [ABSTRACT FROM AUTHOR]

Disubstituted isothiazolo[4,3-b]pyridines are known inhibitors of cyclin G-associated kinase. Since 3-substituted-7-aryl-isothiazolo[4,3-b]pyridines remain elusive, a strategy was established to prepare this chemotype, starting from 2,4-dichloro-3-nitropyridine. Selective C-4 arylation using ligand-free Suzuki-Miyaura coupling and palladium-catalyzed aminocarbonylation functioned as key steps in the synthesis. The 3-N-morpholinyl-7-(3,4-dimethoxyphenyl)-isothiazolo[4,3-b]pyridine was completely devoid of GAK affinity, in contrast to its 3,5- and 3,6-disubstituted congeners. Molecular modeling was applied to rationalize its inactivity as a GAK ligand. [ABSTRACT FROM AUTHOR]

The title compound, C27H20N4O3S, crystallizes in the monoclinic system, space group P21/n, with Z = 4. The global shape of the molecule is determined by the orientation of the substituents on the central 4H-1,2,4-triazole ring. The nitrophenyl ring, phenyl ring, and naphthalene ring system are oriented at dihedral angles of 82.95 (17), 77.14 (18) and 89.46 (15)°, respectively, with respect to the triazole ring. The crystal packing features chain formation in the b-axis direction by S...O interactions. A Hirshfeld surface analysis indicates that the highest contributions to surface contacts arise from contacts in which H atoms are involved. [ABSTRACT FROM AUTHOR]

A new family of unsymmetrical boron chromophores chelated with two BF2 units, named BOPAM, has been developed via a one‐pot, three‐step reaction starting from commercially available thioamides via i) conversion to amidrazones, ii) condensation with pyrrole aldehydes, and iii) boron chelation. This synthetic pathway has been proven to be highly efficient, having a broad substrate tolerance and giving the BOPAM products high yield. Notably, some of the BOPAM dyes show interesting photophysical properties with fluorescence quantum yields up to 0.98 in toluene. A fine‐tuning of their emissive properties has been attained through tailored molecular design strategies guided by in‐depth computational investigations. Tailored substitution with electron‐donating groups at the BOPAM ring leads to the opening of a non‐radiative decay channel involving a dark state and consequently a significant quenching of the fluorescence. The study is complemented by exhaustive steady‐state and time‐resolved spectroscopic measurements. [ABSTRACT FROM AUTHOR]

The molecular and crystal structure of (E)-2-[(benzo[d]thiazol-2-ylimino)- methyl]-5-(diethylamino)phenol (C18H19N3O2S, Et2N-Bz) and its unexpected reaction product with triphenylborane, 2,2-diphenyl-1,3-dioxa-2-borata-1,2-dihydronaphthalene [systematic name: N,N-diethyl-2,2-diphenyl-2H-1,3λ³,2λ4-benzodioxaborinin-7-amine, C23H24BNO2, (I)] are described. For Et2N-Bz, the hydroxyl group is involved in an intramolecular hydrogen bond with the imino nitrogen atom and the C N bond displays an E configuration. The crystal packing is characterized by layers of inversion dimers parallel to the (101) plane and chains of molecule in the a-axis direction formed through C--H⋯O interactions. Complex (I) crystallizes with two molecules (A and B) in the asymmetric unit, which differ in the orientation of the ethyl groups. The 1,3- dioxa-2-borata-1,2,3,4-tetrahydronaphthalene ring displays a slight envelope conformation with the boron atom as the flap. In the crystal packing, chains of alternating A and B molecules formed by C--H⋯O hydrogen bonds run in the b-axis direction. The UV--vis absorption and emission properties of the compounds are discussed and their aggregation-induced emission properties are further investigated. [ABSTRACT FROM AUTHOR]

Sulfur(VI)‐fluoride exchange (SuFEx) chemistry, an all‐encompassing term for substitution events that replace fluoride at an electrophilic sulfur(VI), enables the rapid and flexible assembly of linkages around a SVI core. Although a myriad of nucleophiles and applications works very well with the SuFEx concept, the electrophile design has remained largely SO2‐based. Here, we introduce S≡N‐based fluorosulfur(VI) reagents to the realm of SuFEx chemistry. Thiazyl trifluoride (NSF3) gas is shown to serve as an excellent parent compound and SuFEx hub to efficiently synthesize mono‐ and disubstituted fluorothiazynes in an ex situ generation workflow. Gaseous NSF3 was evolved from commercial reagents in a nearly quantitative fashion at ambient conditions. Moreover, the mono‐substituted thiazynes could be extended further as SuFEx handles and be engaged in the synthesis of unsymmetrically disubstituted thiazynes. These results provide valuable insights into the versatility of these understudied sulfur functionalities paving the way for future applications. [ABSTRACT FROM AUTHOR]

The Nenitzescu reaction is a condensation reaction between an enamine and a quinone, which can give rise to a wide variety of reaction products depending on the nature of the starting material and the reaction conditions. The most commonly observed products are 5-hydroxyindoles and 5-hydroxybenzofurans. Both classes are of interest since they are known to possess a variety of promising bioactivities. Despite the high chemodivergency for this reaction, it remains an interesting synthetic strategy thanks to the mild reaction conditions, easily accessible starting materials and simple reaction procedures. For these reasons, our research group investigated the Nenitzescu reaction of piperazinone enaminoesters, resulting in the unexpected formation of rearranged 2-imidazolidinone benzofurans. In this work, we aimed to develop reaction conditions that favor the formation of 5-hydroxyindoles via an extensive, multivariate optimization study. This led to valuable insights into the parameters that influence regio- and chemoselectivity. Furthermore, two novel products were obtained, a pyrrolo[2,3-f]indole and a benzofuranone, both of which are rarely reported in the literature. [ABSTRACT FROM AUTHOR]

Interactions between the protein Hen Egg White Lysozyme (HEWL) and three different hybrid Anderson–Evans polyoxometalate clusters – AE-NH2 (δ-[MnMo6O18{(OCH2)3CNH2}2]3−), AE-CH3 (δ-[MnMo6O18{(OCH2)3CCH3}2]3−) and AE-Biot (δ-[MnMo6O18{(OCH2)3CNHCOC9H15N2OS}2]3−) – were studied via tryptophan fluorescence spectroscopy and single crystal X-ray diffraction. Quenching of tryptophan fluorescence was observed in the presence of all three hybrid polyoxometalate clusters (HPOMs), but the extent of quenching and the binding affinity were greatly dependent on the nature of the organic groups attached to the cluster. Control experiments further revealed the synergistic effect of the anionic polyoxometalate core and organic ligands towards enhanced protein interactions. Furthermore, the protein was co-crystallised with each of the three HPOMs, resulting in four different crystal structures, thus allowing for the binding modes of HPOM–protein interactions to be investigated with near-atomic precision. All crystal structures displayed a unique mode of binding of the HPOMs to the protein, with both functionalisation and the pH of the crystallisation conditions influencing the interactions. From the crystal structures, it was determined that HPOM–protein non-covalent complexes formed through a combination of electrostatic attraction between the polyoxometalate cluster and positively charged surface regions of HEWL, and direct and water-mediated hydrogen bonds with both the metal-oxo inorganic core and the functional groups of the ligand, where possible. Hence, functionalisation of metal-oxo clusters shows great potential in tuning their interactions with proteins, which is of interest for several biomedical applications. [ABSTRACT FROM AUTHOR]

The title compound, C10H14BrN5O2S, is the bromobenzenesulfonamide derivative of the type 2 diabetes drug metformin. The asymmetric unit contains two molecules with almost identical conformations but a different orientation of the bromophenyl moiety. Both molecules exhibit intramolecular N--H· · ·N and N--H· · ·O hydrogen bonds. The molecular packing features chain formation in the a-axis direction by alternating N--H· · ·N and N--H· · ·O interactions. In addition, ring motifs consisting of four molecules and π-π interactions between the phenyl rings contribute to the three-dimensional architecture. A Hirshfeld surface analysis shows that the largest contributions to surface contacts arise from contacts in which H atoms are involved. [ABSTRACT FROM AUTHOR]

rsCherryRev1.4 has been reported as one of the reversibly photoswitchable variants of mCherry, and is an improved version with a faster off‐switching speed and lower switching fatigue at high light intensities than its precursor rsCherryRev. However, rsCherryRev1.4 still has some limitations such as a tendency to dimerize as well as complex photophysical properties. Here, the crystal structure of rsCherryRev1.4 was determined at a resolution of 2 Å and it was discovered that it forms a dimer that shows disulfide bonding between the protomers. Mutagenesis, gel electrophoresis and size‐exclusion chromatography strongly implicate Cys24 in this process. Replacing Cys24 in rsCherryRev1.4 resulted in a much lower tendency towards dimerization, while introducing Cys24 into mCherry correspondingly increased its dimerization. In principle, this finding opens the possibility of developing redox sensors based on controlled dimerization via disulfide cross‐linking in fluorescent proteins, even though the actual application of engineering such sensors still requires additional research. [ABSTRACT FROM AUTHOR]

Eight polythiophene derivatives containing pyrazoline side groups were synthesized by a chemical oxidative coupling polymerization using FeCl3. The crystal structures of four monomers were determined which confirm the almost perpendicular orientation of the thiophene and pyrazoline rings, while the other substituents are more coplanar. Analyses of IR, 1H-NMR, Raman and UV-Vis spectra demonstrated that the suggested polymerization was successful to generate the synthesized polythiophenes with the expected structures. The morphology of the synthesized polythiophenes was studied by SEM. The different substituents attached to the 1- and 3-positions of the pyrazoline side chain led to differences in optical properties, electrical conductivity, and thermal stability of the synthesized polythiophenes. By adding a pyrazoline side chain to polythiophenes, some polymers achieve good solubility, electrical conductivity of about 1.3 × 10–6 S/cm, high fluorescence intensity (above 40,000 a.u.) at 505–550 nm and thermal stability up to 590°C in the air. [ABSTRACT FROM AUTHOR]

In this work, a novel compound N-(3-(4-methoxyphenyl)isoxazolin-5-yl)methylsaccharin has been synthesized. The molecular structure of the compound was determined using various spectroscopic techniques and confirmed by a single-crystal X-ray diffraction analysis. In the single crystal, C–H...O hydrogen bonds between neighboring molecules form chains along the a-axis direction. Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H...H (35.7%), H...O/O...H (33.7%), and H...C/C...H (13%) interactions. The optimized structure calculated using density functional theory at the B3LYP/6–311 G(d,p) level is compared with the experimentally determined structure in the solid state. The calculated highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy gap is 4.9266 eV. [ABSTRACT FROM AUTHOR]

The reaction of complexes [Pt(μ‐Cl)(arylolefin)]2 with various either weak σ‐donor LN,S,O ligands or strong σ‐donor NHCs ligands results in [PtCl(arylolefin)(LN,S,O)] with LN,S,O in a cis position to the C=C group (series A) or [PtCl(arylolefin)(NHC)] with NHC in a trans position to the C=C group (series B), respectively. The reaction directions are decided by the nature of the reactants, and not by the reaction conditions. Analyses of NMR spectra, XRD and DFT results indicate that the formation of series B is strongly dominated by electronic properties, while steric factors direct the reaction to form series A. The chemical shifts of ethylenic protons and carbons as well as the values of 2JPtH, 3JPtH for the allyl protons and the 3JPtH value for H6 in the aryl group are unambiguously different for series A and series B. In addition, one complex [Pt(μ‐Cl)(EtEug)]2 and five complexes [PtCl(arylolefin)(NHC)] have been characterized by single crystal XRD. [ABSTRACT FROM AUTHOR]

An easily accessible experimental set-up to grow large single crystals of two sweeteners readily available in supermarkets, erythritol and xylitol, is described. The crystallization of these compounds illustrates the principles of crystallization by evaporation. As these artificial sweeteners are also known to induce a cool sensation in the mouth, the crystal-growing experiment is complemented with a simple calorimetric set-up to demonstrate the endothermic nature of the dissolution of the selected sweeteners in a more quantitative approach by measuring the heat of dissolution (ΔHdiss). The choice of these two sweeteners also allows use of the freely available WebCSD and Mercury tools to visualize their three-dimensional structure, crystal packing and powder diffractograms, and to deepen stereochemical concepts such as stereoisomers and meso compounds. [ABSTRACT FROM AUTHOR]

A green multicomponent synthesis of previously unreported octahydropyrimido[4,5-g]quinazoline-5,6-diones was developed from simple building blocks. These highly symmetrical compounds show strong propensity to self-assembled molecular network (SAMN) formation on highly oriented pyrolytic graphite. The SAMN type is easily tunable by changing molecular characteristics. The redox behavior was studied by cyclic voltammetery. [ABSTRACT FROM AUTHOR]

Uranyl complex dissolved in room-temperature ionic liquids has diagnostic absorption and emission spectra that has allowed the identification of the symmetry and geometry of the complex. The uranyl complexes are examined in imidazolium and pyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquids.

A general method is described for the synthesis and purification of hydrophilic ionic liquids, choline saccharinate and choline acesulfamate. The analysis has shown that choline saccharinate and choline acesulfamate are ionic liquids with a low toxicity, as these ionic liquids are composed of animal feed additives and of additives for human nutrition.