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Cyclopropylchloromethyldifluorosilane, c-C3H5SiF2CH2Cl, has been synthesized, and its rotational spectrum has been recorded by chirped-pulse Fourier transform microwave spectroscopy. The spectral analysis of several isotopologues indicates the presence of two distinct conformations in the free-jet expansion, which are interconvertible through a rotation of the chloromethyl group. A partial substitution structure is presented for the lower energy conformation and is compared to the equilibrium structure obtained from quantum chemical calculations. Additionally, the presence of the chlorine nucleus leads to the rotational transitions splitting into multiple hyperfine components and χaa, a measure of the electric field gradient along the a axis, is unusually small at merely +0.1393(73) MHz. Various common ab initio and density functional theory methods fail to predict good quadrupole coupling constants (in the principal axis system) that adequately reproduce the observed hyperfine splitting, although diagonalizing the quadrupole coupling tensor from the principal axis system into a nucleus-centered axis system reveals that, overall, these methods calculate reasonably the electric field gradient about the chlorine nucleus. Finally, a total of nine electric dipole forbidden, quadrupole allowed transitions are observed in the rotational spectra of the parent species of the higher energy conformation and the 37Cl isotopologue of the lower energy conformation. These include those of x-type (no change in parity of Ka or Kc), which, to our knowledge, is the first time such transitions have been observed in a chlorine-containing molecule. [ABSTRACT FROM AUTHOR]

In this paper, porous Brønsted acidic ionic liquid modified catalyst ILs-AB-8 was successfully synthesized by using 3 steps of Friedel–Crafts hyper-crosslinking synchronous chloromethylation, imidazlole grafting and sulfonic functionalization using macroporous polystyrene AB-8 resin as a raw material. The porous ionic liquid immobilized catalyst ILs-AB-8 exhibits a hierarchical pore structure by the coexistence of abundant macropore, mesopore, and micropore. The catalyst IL2-AB-8 with dual Brønsted acid sites(-SO3H acid site and p-methylbenzenesulfonic acid site), large surface area (327.19 m2/g), high ionic liquid loading amount (IEC 2.03 mmol/g) displayed excellent catalytic activity, with methyl oleate yield up to 95.65% at 338 K in 100 min. The enhanced catalytic performance of IL2-AB-8 can be ascribed to the novel Friedel–Crafts hyper-crosslinking process in conjunction with chloromethylation, coupled with th in situ generated activating chloromethyl group incorporated onto the surface of the AB-8 carrier. The hyper-crosslinking approach also effectively transforms the macroporous AB-8 carrier into a multi-level pore structure. This work highlights that IL2-AB-8 with high specific surface area, ionic liquid loading content, and strong covalent connection with carrier was coordinated to provide an efficient metal-free heterogeneous catalyst for biodiesel production. [ABSTRACT FROM AUTHOR]

The study reports a tactic for superior antibacterial performance on cotton via synergism of complementary functionalities of quaternary ammonium salt and malonylurea-based N-chloramine combined in a silane. Knoevenagel Condensation between 4-(chloromethyl)benzaldehyde and malonylurea formed a product whose chloromethyl group was used to quaternize tertiary amine of N,N-dimethylethanolamine. The O − H of the quaternization product was subsequently alcoholyzed with Si − H of trimethoxysilane. The methoxysilyl groups of the alcoholysis silane were hydrolyzed to silanol ones that condensed with either their own kind or hydroxy groups of cellulose to polymerize into a crosslinked polysiloxane finishing on cotton. Upon chlorination of malonylurea-based N − H bonds, each repeating unit of the polysiloxane has one quaternary ammonium salt and two imide N-chloramine sites. Antibacterial assays against Staphylococcus aureus and Escherichia coli proved that the synergism of quaternary ammonium salt and N-chloramine, a higher efficacy and a broader spectrum arising from their complementary elimination mechanisms and physiochemical features. Biocidal stability and rechargeability of the polysiloxane finishing were both promising due to the robust and hydrophobicity of silicone backbone and the sturdy cyclic N-chloramine. This research presented a general approach for generation of super biocidability on substrates that can react with hydroxy group using silanes to carry complementary functionalities. [ABSTRACT FROM AUTHOR]

Analysis of the effect of steric compression on the chemical shifts of carbons (13C NMR) in diastereoisomers is an accessible strategy for assigning the absolute configuration of secondary alcohols. Here we take advantage of such chemical shift differences and establish a validation protocol to assign the absolute configuration of secondary alcohols in natural products. The two enantiomers of methyl-1-(chloromethyl)-5-oxopyrrolidine-2-carboxylate are used as derivatizing agents to treat separately a secondary alcohol producing two diastereoisomeric derivatives. These derivatives exhibit clear 13C NMR differences only at four carbons: first at the stereogenic oxygenated carbon and methylene of the chiral assistant with a deshielding effect up to 3 ppm, and a shielding effect for the α carbons to the stereogenic centre. With the results obtained from a 1D NMR 13C spectrum, we were able to establish the absolute stereochemistry of the asymmetric centre beyond the concept of anisotropy. The observed changes in chemical shifts correlate well with the results obtained by the GIAO method applying the B3LYP/6-311+(2d,p) theoretical model to calculate the NMR shielding tensors of the diastereoisomeric derivatives. Furthermore, the steric compression effect was observed as well by 1H NMR at the methylene of the pyroglutamic moiety, since the magnitude of its geminal coupling constant is directly influenced by the stereochemistry of the secondary alcohol, thus, confirming the stereochemistry assignation of the asymmetric carbon. [ABSTRACT FROM AUTHOR]

The reaction between N, N′-diaryl-4-chloromethylimidazolium chlorides and N-nucleophiles, viz. various azoles and azines, which proceeds via nucleophilic substitution of the chlorine atom in the chloromethyl group and leads to new dicationic 4-hetarylmethylimidazolium salts, was investigated. This reaction is reversible, whereas the yield of product of the nucleophilic substitution depends significantly on the structure of heterocyclic nucleophile and the nature of used solvent. A series of new dicationic 4-hetarylmethylimidazolium salts was obtained, and they are of interest as promising components of ionic liquids and precursors of N-heterocyclic carbenes. [ABSTRACT FROM AUTHOR]

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Dielectric elastomer actuators (DEAs) are a class of soft transducers with broad potential applications in soft robotics. DEAs consist of two stretchable electrodes on a dielectric elastomer, which deform and generate force when charged. The generated force is increased by placing many DEAs on top of one another to form a stack actuator. Next‐generation stack actuators require high permittivity inks that are solvent‐free processable and cross‐linkable into thin elastic films. Here, a process toward elastomers with tuneable permittivity that can be prepared solvent‐free is reported. Polycondensation of chlorosilanes yields polymers with vinyl end‐groups and cross‐linkers with multiple hydrosilane groups that both carry polar chloromethyl groups. Their dielectric permittivity and mechanical properties are tuned by changing the polar group content and the molar mass of the vinyl‐terminated polymer, respectively. Solvent‐free doctor blading provides thin films, which are cross‐linked by heating. DEAs prepared from the films reach a lateral actuation of promising 4.6% at a low electric field of 11.2 V µm‐1 and can be operated at frequencies up to 5 Hz. The high‐permittivity polymer ink is used in a solvent‐free layer‐by‐layer stack actuator fabrication, which yields an actuator with three active layers that gives a thickness strain of 1.0% at 12.4 V µm‐1. [ABSTRACT FROM AUTHOR]

A series of novel derivatives of dipyrimido[4,5-b:4′,5′-e][1,4]thiazepine were synthesized by the treatment of 2,4-dichloro-5-(chloromethyl)-6-methylpyrimidine with 2-substituted-5-amino-6-methyl-pyrimidine-4-thiol in the presence of trimethylamine in acetonitrile as solvent and subsequently with various appropriate amines in boiling ethanol. The regioselectivity of heterocyclizaion was confirmed by GIAO calculations. The theoretical result revealed that the attachment of -SH moiety to the CH2 group is more plausible. Also, the theoretical inhibitory activity of the newly synthesized compounds against soybean 15-lipoxygenase was studied. The docking results showed that the theoretical inhibitory activity (ki) of compounds (10a), (10b), (10e), (10j) was lower than 4-MMPB as the standard inhibitor of 15-SLO. Among them, compound (10e) was a potent theoretical inhibitor with (Ki = 1.13 nM) and binding energy −12.21 kcal mol−1. We propose that the orientation of the four synthesized compounds toward the Fe-OH and the hydrogen bond interaction between a sulfur atom of thiazepine ring and His 518 of 15-lipoxygenase seems to play an essential role in lipoxygenase inhibition. [ABSTRACT FROM AUTHOR]

The article invites readers to participate in the Analytical Challenge, a series of puzzles published in the journal "Analytical and Bioanalytical Chemistry." The current challenge focuses on NMR spectroscopy and asks participants to propose a name for a phenomenon in which chemically non-equivalent nuclei produce NMR signals with identical chemical shifts. The article provides two examples of this phenomenon and asks readers to submit their solutions by a specified date. The winner will receive a prize and their name will be published in the journal. [Extracted from the article]

The nitramino group is an important motif in energetic compounds, positively influencing the oxygen and nitrogen content, density and enthalpy of formation. Herein, a simple, mild and general procedure has been developed for the preparation of diverse N-(chloromethyl)nitramine building blocks from readily available N-(acetoxymethyl)nitramines via a TiCl4-catalyzed chlorodeacetoxylation with SOCl2. This new protocol allows the conversion of both mono- and di(acetoxymethyl) precursors that contain one to four nitramino groups into functionalized chloromethyl compounds in excellent yields. [ABSTRACT FROM AUTHOR]

We report the development of bifunctional trifluoromethylsilyl reagents for selective trifluoromethylation. The newly developed reagent, Me2(CH2Cl)SiCF3, allows highly enantioselective trifluoromethylations of ketones with broad scope. Notably, by taking advantage of the chloromethyl group, a tandem synthesis of chiral trifluoromethylated oxasilacyclopentanes is developed, paving way to α‐CF3 tertiary alcohols with vicinal tertiary or quaternary stereocenters. Theoretical studies revealed the important role of nonclassical C−H⋅⋅⋅F−C interactions in stabilizing the transition state, and that the presence of the chlorine atom enhances such interactions for better enantiofacial control. [ABSTRACT FROM AUTHOR]

Fluorescent polymer nanoparticles (NPs) have great potential as bioimaging and therapeutic agents in the biomedical field. Here, a subtle method is developed to synthesize inherently fluorescent core–shell NPs with diameters less than 100 nm. The permanent fluorescence comes from the rigid conjugated structure between benzene and chloromethyl groups in the crosslinked poly(chloromethylstyrene) (PCMSt) core, which is able to be applied for the determination of Fe3+ with a detection limit of 1.39 × 10−6 m. It is further demonstrated that the galactose modification (poly (6‐O‐acryloyl‐d‐galactose), PADGal) shell can efficiently· facilitate the selective internalization of NPs by human hepatocellular carcinoma cells (HepG2), and the cells are more prone to uptake the NPs with medium crosslinking degree. The hydrophobic anticancer drug 10‐hydroxycamptothecin (HCPT) is then loaded onto PADGal@PCMSt NPs. Benefiting from the specific interactions between asialoglycoprotein (ASGP) receptors and the galactose moiety, the PADGal@PCMSt NPs can deliver HCPT with the highest efficiency to HepG2 cells in comparison with the human cervical cancer cells (HeLa), the human alveolar adenocarcinoma basal epithelial cells (A549), the mouse breast cancer cells (4T1), and the mouse fibroblast cells (NIH3T3). The present study provides a new strategy to build small‐size fluorescent polymer NPs with both bioimaging and therapeutic functions. [ABSTRACT FROM AUTHOR]

Schematic representation of phospholipid-modified polyethersulfone membrane surface resist non-specific adhesion. [Display omitted] • The phospholipid biomimetic PES membranes are prepared by simple in-situ blending under mild conditions. • The biomimetic membranes possess excellent anti-protein adhesion and anticoagulation properties. • The complement activation and biofilm formation are efficiently inhibited on the membrane surface. Hemodialysis (HD) is one of the most important treatments for patients suffering from kidney failure, and polyethersulfone (PES) is the most common type of hemodialysis membrane. However, owing to insufficient biocompatibility and lending to the dilemma of its coagulation and bleeding risk in clinical applications, it limited the service life of hemodialyzer and seriously affected the dialysis safety of patients. In this paper, phospholipid biomimetic PES membranes were prepared by in situ blending between the hydrophilic polymer (PMAPC) rich in amino groups and the chloromethyl functional polyethersulfone (CMPES), which made up for the shortcomings of the hydrophilic additives that were easy to elate. Characterization and evaluation showed that the modified PES membrane had excellent hydrophilicity and stability. Furthermore, it could also effectively inhibit platelet adhesion activation and fibrinogen adsorption denaturation, suppress complement activation, and prolong coagulation time. The in vitro blood circulation experiment further confirmed the excellent anticoagulant activity of the modified membrane. The modification and preparation methodology described in this paper was simple and practical under mild reaction conditions, low cost, and easy to industrialize. This research lays the foundation for potential applications of phospholipid-mimicking PES membranes in hemodialysis. [ABSTRACT FROM AUTHOR]

Substituted-benzyl-containing N-methyl-ephedrinium derivatives (BMEP), prepared from the highly-accessible (1 R ,2 S)- or (1 S ,2 R)-ephedrine alkaloids, have been found to act as efficient structure-directing agents for the synthesis of chiral zeolite GTM-4 with –ITV framework structure, promoting the enantio-enrichment in one of the chiral crystalline polymorphs as a function of the organic handedness. Results of a systematic variation of substituents in the benzyl ring attached to the ephedrine core (with methyl-, fluoro- or chloro-groups in the different positions of the aromatic ring) revealed that F-containing SDAs brought about an improvement in the structure-directing ability toward the –ITV framework, giving asymmetric zeolite acid-catalysts that yielded notable enantiomeric excesses in the range of 40–45 % for the trans -stilbene oxide ring-opening with 1-butanol. Interestingly, the incorporation of a methyl group in ortho-position (oMBMEP) had a double positive effect: on the one hand, this SDA prevented the crystallization of the competing BEC phase, allowing the crystallization of the -ITV structure at higher temperature and with higher crystallinity, and on the other, it drove to GTM-4 asymmetric catalysts that yielded enantiomeric excesses up to 60 %, resulting in the chiral GTM catalysts with the best enantioselective properties found so far. Remarkably, our catalytic results show the same chiral activity (in terms of zeolite handedness) for GTM-4 materials prepared from benzyl-containing (1 S ,2 S)-N-methyl-pseudoephedrinium (BMPS) and (1 S ,2 R)-N-methyl-ephedrinium (BMEP) derivatives, thus suggesting that the host-guest transfer of chirality during crystallization with these chiral organic aromatic agents is imposed by the absolute configuration of the C1 atom to which the OH group is attached. The relatively high enantiomeric excess of 60 % achieved, combined with the high accessibility of the ephedrine chiral precursors used for the synthesis that enables the production of both crystalline handedness of the –ITV framework, bring these materials closer to a potential application as heterogeneous asymmetric catalysts for the synthesis of chiral compounds of interest. [Display omitted] • Ephedrine-derived organic cations direct the synthesis of the –ITV structure. • Substitution of the benzyl ring alters the enantio-enrichment of the –ITV structure. • Enantioselectivities up to 60 % of enantiomeric excesses are achieved. [ABSTRACT FROM AUTHOR]

The electrolyte membrane plays a pivotal role in high temperature proton exchange membrane fuel cells (HT-PEMFCs). Herein, we develops a new triarylmethane-backboned polymer, poly (biphenyl dimethylamino benzene) (PBDAB), synthesized through a facile one-step Friedel-Crafts reaction using biphenyl and 4-(dimethylamino) benzaldehyde as monomers. The presence of tertiary amine groups in PBDAB facilitates strong interactions with phosphoric acid (PA) molecules. To enhance the membrane's dimensional and mechanical stabilities, covalent crosslinking is performed via the Menshutkin reaction between the tertiary amine groups in PBDAB and chloromethyl groups in various crosslinkers. In order to study the influence of crosslinker chemical structure on the properties of PBDAB-based membranes, five different crosslinkers are employed, including small-molecule types such as 1,2-bis(2-chloroethoxy) ethane (BCE) and 1,4-bis(chloromethyl) benzene (BCB), siloxane type 3-chloropropyl (trimethoxy) silane (CTS), polymer types such as poly (vinylbenzyl chloride) (PVBC) and polyepichlorohydrin (PECH). Results reveal that the flexible and ether containing polymer crosslinker of PECH crosslinked membrane, denoted as CL-y%PECH, exhibits superior overall performance. When doped in an 85 wt% PA solution, the CL-5%PECH membrane achieves a PA uptake of 201%, resulting in an anhydrous proton conductivity of 0.064 S cm−1 at 180 °C and a mechanical strength of 7.2 MPa at room temperature. Using H 2 and O 2 as fed gases without humidification and backpressure, a single cell with abovementioned membrane attains a peak power density of 302 mW cm−2 at 160 °C. This work offers a kind of promising PBDAB based membranes for HT-PEMFC applications. [Display omitted] • Crosslinked poly (biphenyl dimethylamino benzene) membranes are synthesized for HT-PEMFCs. • Macromolecular PECH crosslinked membranes exhibit superior overall performance. • CL-5%PECH/201%PA membrane exhibits a H 2 –O 2 fuel cell peak power density of 302 mW cm−2 at 160 °C without backpressure. [ABSTRACT FROM AUTHOR]

The synthesis of 6-chloro-(dichloro-, trichloro)methyl-3-R-6,7-dihydro-2H-[1.2.4] triazino[2,3-c]quinazolin-2-ones and their modification under the action of nucleophilic and/or basic reagents are described in this article. It was shown that 6-chloro-(dichloro-, trichloro)methyl-3-R-6,7-dihydro-2H-[1,2,4]triazino[2,3-c]quinazolin-2-ones can be prepared by cyclocondensation of 3-(aminophenyl)-6-R-1,2;4-triazine-5(2W)-ones with chloro-(dichloro-)acetaldehyde or chloral hydrate. The reactivity of the synthesized compounds toward nucleophilic base morpholine and non-nucleophilic base diisopropylethylamine (DIPEA) under different conditions was studied. It was shown that the prepared compounds under the action of morpholine and/or DIPEA can be converted into the products of substitution, elimination or elimination followed by isomerization and substitution. Refluxing of 6-(chloromethyl)-3-R-6,7-dihydro-2 H-[1.2.4] triazino[2,3-c]quinazoline-2-ones with equimolar quantity of morpholine and 10% excess of DIPEA in ethylene glycol monoethyl ether (EGEE) yielded the products on N-alkylation. 6-(Morpholinomethyl)-3-R-2 H-[1,2,4]triazino[2,3-c]quinazoline-2-ones were obtained by heating of 6-dichloromethyl-3-R-6,7-dihydro-2H-[1,2,4]triazino[2,3-c]quinazoline-2-ones with five-fold excess of morpholine in EGEE. Reaction of 3-R-6-(trichloromethyl)-6,7-dihydro-2 H-[1,2,4]triazino[2,3-c]quinazolin-2-ones with three-fold excess of DIPEA in EGEE yielded 3-R-2#-[1,2,4]triazino[2,3-c]quinazoline-2-ones. The physicochemical and spectral characteristics of the prepared compounds were determined and discussed. [ABSTRACT FROM AUTHOR]

Alkaline membrane (AM) shows fast transport of OH− towards the anode, separates both electrodes, and prevents fuel cross-over. To achieve good membrane conductivity and performance, high concentration of positively charged groups (quaternary ammonium) is an essential requirement, which also leads excessive swelling and mechanical instability of the AMs. Further, directly grafted quaternary ammonium (QA) with main polymer chain substitution and/or elimination reactions under strong alkaline environment. To avoid above-mentioned problems, we report preparation of cross-linked chloromethylated polysulfone based AM using (4,4,-((3,3′-bis(chloromethyl)-[1.1′-biphenyl]-4,4-diyl)bis(oxy))dianiline) (BCBD), a multi-functional novel cross-linking agent. Reported strategy compensates 2 mol of chloromethyl groups consumed during cross-linking, but additional functional groups (4 mol) with cross-linking agent. These AMs are designed to avoid the nucleophilic substitution (S N 2) (grafting quaternary ammonium (QA) groups at benzylic position), and Hofmann elimination (E2) reactions (unavailability of β -H), under strong alkaline environment. Effective cross-linking has been confirmed by spectral analysis, and improves membrane stabilities and fuel cell performance. Single-cell alkaline membrane fuel cell (AEMFC) performance of most suitable (CR-QPS-03) membrane, showed comparatively high performance (open circuit voltage (OCV): 0.813 V, maximum power density: 103.6 mW/cm2 at 260.0 mA/cm2) in compare with Nafion 117 membrane (OCV: 0.682 V, maximum power density: 63.36 mW/cm2 at 220.0 mA/cm2) under similar experimental conditions. Image 1 • Multi-functional cross-linked alkaline membrane for fuel cell application. • Improved ionic nature of membrane by grafting of functional groups with cross-linker. • Alkaline stability in absence of β -hydrogen and S N 2 reaction. • CR-QPS-03 a.m. with higher fuel cell performance than Nafion 117 membrane. [ABSTRACT FROM AUTHOR]

In this study, a one-pot, solvent-free stereoselective reaction was started between primary amines, carbon disulfide, ethyl bromoacetate, and furan derivatives derived from sugars at room temperature, which was completed within 10 min to produce rhodanine–furan hybrid molecules in good to high yields. The presence of the chloromethyl group in products derived from chloromethylfurfural (CMF) made it possible for the substitution of other functional groups such as amine group. [ABSTRACT FROM AUTHOR]

The chemical properties of 3-amino-4-[5-(chloromethyl)-1,2,4-oxadiazol-3-yl]furazan were scrutinized: acylation of the amino group and its oxidation to azo and nitro groups, reactions of the chloromethyl group with N- and S-nucleophilic reagents, as well as reactions of transformation of the 1,2,4-oxadiazole ring. [ABSTRACT FROM AUTHOR]

The photodissociation of the chloromethyl radical, CH[sub 2]Cl, to chlorine atom and methylene is examined following excitation at selected wavelengths in the region 312–214 nm. CH[sub 2]Cl is produced in a molecular beam by using pulsed pyrolysis. Cl and CH[sub 2] products are detected by laser ionization and their velocity and angular distributions are determined by using the ion imaging technique. The spectrum obtained by monitoring the Cl fragment yield as function of photolysis wavelength shows that throughout this wavelength region Cl atoms are major products. With 312–247 nm photolysis, the angular distributions are typical of a perpendicular transition (β=-0.7) and the main products are CH[sub 2](X˜ [sup 3]B[sub 1])+Cl([sup 2]P[sub 3/2]). The available energy is partitioned preferentially into the translational degrees of freedom. “Hot band” transitions are prominent in this region even in the molecular beam indicating that the geometries of the ground and excited states of CH[sub 2]Cl must be very different. With 240–214 nm photolysis, the angular distributions are typical of a parallel transition (β∼1.2), and the predominant products are Cl([sup 2]P[sub 3/2]) and Cl([sup 2]P[sub 1/2]), with CH[sub 2](a˜ [sup 1]A[sub 1]) as the main cofragment. A large fraction of the available energy is partitioned into internal energy of CH[sub 2](a˜ [sup 1]A[sub 1]). Comparison with the ab initio calculations of Levchenko and Krylov presented in the accompanying paper enables the assignment of the perpendicular and parallel transitions predominantly to 1 [sup 2]A[sub 1]←1 [sup 2]B[sub 1] and 2 [sup 2]B[sub 1]←1 [sup 2]B[sub 1] excitations, respectively, and both upper states are probably repulsive in the C–Cl coordinate. The electronic states of the products obtained via these two transitions are in agreement with the predictions of a simple diabatic state correlation dia... [ABSTRACT FROM AUTHOR]

Reactions of 2-and 3-furoyl chlorides having chloromethyl or butylthiomethyl group in the adjacent position of the furan ring as well as of analogous N-morpholinomethylfuroyl chloride hydrochlorides with triethyl phosphite have been studied. The synthesized chloromethylfuroyl phosphonates have given the corresponding products of nucleophilic substitution in the reactions with sodium azide and potassium thiocyanate in the case of 4-chloromethyl-3-furoyl phosphonate. In the reaction of 3-chloromethyl-2-furoyl phosphonate with sodium azide, cleavage of the P-C bond takes place simultaneously with nucleophilic substitution. Potassium thiocyanate forms 3-thiocyanatomethyl-2-furoyl phosphonate in the reaction with this substance. The synthesized stable furoyl phosphonates enter the Wittig reaction with resonance-stabilized phosphoranes to give phosphorylated furylalkenes. If these compounds carry a chloromethyl group in the furan ring, they react with sodium azide and potassium thiocyanate to give the corresponding products of nucleophilic substitution. Analogously, aminomethyl derivatives have been obtained in the reaction with morpholine at room temperature. [ABSTRACT FROM AUTHOR]

A series of crosslinked, ammonium‐functionalized, and partially fluorinated copolymers have been prepared and evaluated as anion exchange membranes. In order to investigate the effect of crosslinking on the membrane properties, precursor copolymers containing chloromethyl groups were crosslinked with various aliphatic diamines followed by quaternization with monoamines. Crosslinking was effective in lowering water absorbability at no expense of high hydroxide ion conductivity of the membranes. By tuning the degree of crosslinking (20 mol %) and crosslinker chain length (C6 and C8), the highest ion conductivity of 73 mS/cm (at 80°C in water) was achieved. Furthermore, alkaline stability of the membranes was also improved by the crosslinking; the remaining ion conductivity after the stability test (in 1 M potassium hydroxide at 80°C) was 8.2 mS/cm (after 1000 h) for the C6 crosslinked membrane and 1 mS/cm (after 500 h) for the uncrosslinked membrane, respectively. The ammonium groups attached with the crosslinkers seemed more alkaline stable than the uncrosslinked benzyltrimethylammonium groups, while the polymer main chain was intact under the harsh alkaline conditions. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1059–1069 [ABSTRACT FROM AUTHOR]

Abstract Poly[4,4′-(diphenyl ether)-5,5′-bibenzimidazole] (oPBI) based high temperature proton exchange membranes are prepared by covalent cross-linking with chloromethylated polysulfone (CMPSU) and doping with zirconium phytate (ZrPA). ZrPA is synthesized as the proton conductor through a facile method from zirconyl chloride and phytic acid which is abundant and readily available. oPBI is cross-linked by CMPSU and that hydrogen bonds are formed between ZrPA and oPBI-CMPSU. The composite membranes are dense without through holes when doping with ZrPA. The composite membranes exhibit good thermal stability below 140 °C. Meanwhile, the composite membranes reveal good mechanical strength and methanol resistance. The oxidative stability is improved because of cross-linking and the doping of ZrPA. Conductivities of oPBI-CMPSU/ZrPA at different temperatures and relative humidity (RH) are investigated. At 100% RH, 50% RH and 0 RH, the conductivity of oPBI-CMPSU(20%)/ZrPA(30%) can reach 0.072 S/cm, 0.025 S/cm and 0.012 S/cm at 140 °C, respectively. Although the proton conductivity of the composite membrane was not particularly high at 100% RH, the composite membrane comparatively exhibited good proton conductivity at high temperature and at 50% RH and 0 RH. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

The C‐C ring closure of α‐chloromethyl alkyl or aryl N‐aryl imines catalyzed with 1 to 10 % Pd(OAc)2/P(p‐tolyl)3 afford efficiently 2‐aryl‐ and 2‐alkyl‐1H‐indoles. The heterocyclization reaction involves the initial formation of [2‐(arylimino)ethyl]palladium(II) chloride complexes with subsequent C‐H activation of the aromatic amine ring. Readily or commercially available α‐chloromethyl‐aryl or ‐alkyl ketones are used as the precursors. Functionalized indoles at the benzene ring are obtained when the imines are derived from substituted anilines. Palladium‐catalyzed heterocyclization of α‐chloromethyl alkyl or aryl N‐aryl imines gives efficiently 2‐aryl‐ and 2‐alkyl‐1H‐indoles. Readily or commercially available α‐chloromethyl‐aryl or ‐alkyl ketones are used as the precursors. Indoles containing substituents, including halogens, at the benzene ring are also easily accessible simply by use of the appropriate substituted aromatic amine. [ABSTRACT FROM AUTHOR]

Abstract We designed and synthesized a poly(ether imide) (PEI) membrane that has good chemical and mechanical stabilities. Alkalized PEI (A-PEI) membrane was fabricated by solution casting of chloromethylated PEI (CM-PEI) followed by quaternization and alkalization. The chemical structure of the synthesized polymers was verified by proton nuclear magnetic resonance (1H NMR) and Fourier-transform infrared spectroscopy (FT-IR). Physiochemical properties of the membrane such as ion exchange capacity, water uptake, and swelling ratio were investigated. The membranes with a high degree of chloromethylation (DC) exhibited elevated hydroxide ion conductivity in range of 6.7–44.2 mS/cm at 90 °C under 100% relative humidity (RH). The hydrophilic-hydrophobic phase separation was verified by atomic force microscope (AFM) and small angle X-ray scattering (SAXS) measurements. Chemical stability was evaluated by measuring the durability of membranes while they were soaked in oxidative and alkaline solutions at 60 °C for 200 h. Graphical abstract Extended chemical stability of membranes evaluated by (a) oxidative and (b) alkaline stability tests after 200 h. Image 1 Highlights • Novel A-PEI membranes were prepared via facile polycondensation reaction. • The prepared PEI membranes displayed superior thermal and oxidative stability. • Ion conductivity of the A-PEI-8 membrane was found to be excellent. • A-PEI-8 membrane exhibited good alkaline stability under extreme condition. [ABSTRACT FROM AUTHOR]

5-Chloromethyl-2-furoyl chloride when treated with triethyl phosphite has given 5-chloromethyl-2-furoyl phosphonate. This compound has reacted with sodium azide in the presence of potassium iodide to give 5-azidomethyl-2-furoyl phosphonate. Treatment of 5-chloromethyl-2-furoyl phosphonate with secondary amines even under mild conditions has caused cleavage of P–C bond with liberation of diethyl hydrogen phosphite and formation of 5-chloromethyl-2-furancarboxamide. Butanthiol in the presence of potassium carbonate in acetonitrile has converted the chloromethyl group into the butylthiomethyl one and simultaneously split the P–C bond with the formation of the corresponding thioester. Under the action of S-methylthiuronium iodide and triethylamine, 5-chloromethyl-2-furoyl phosphonate has been unexpectedly reduced into the 5-methyl derivative. 5-Butylthiomethyl- and 4-(N-morpholinomethyl)-2-furoul chlorides have been phosphorylated with triethyl phosphite into the corresponding 5-functionalized 2-furoyl phosphonates. The prepared furoyl phosphonates have reacted with resonance-stabilized phosphoranes to give phosphorylated derivatives of 3-(furyl)acrylates and 4-(furyl)but-3-en-2-one with trans-location of phosphoryl and carbonyl groups with respect to the double bond. [ABSTRACT FROM AUTHOR]

In the functionalization of salicylaldehyde to give 5-(chloromethyl) salicylaldehyde, two byproducts [5-(hydroxymethyl)salicylaldehyde and 5,5'-methylenebis(salicylaldehyde)] were also isolated. Detailed characterizations and structural analyses of all three products by single-crystal X-ray diffraction, multinuclear NMR spectroscopy, high-resolution mass spectrometry, and IR spectroscopic techniques are presented and discussed. A strategy is presented for the preferential isolation of the two byproducts through column chromatography. [ABSTRACT FROM AUTHOR]

A series of post-crosslinked resins were synthesized from macroporous chloromethylated styrenedivinylbenzene copolymer by controlling post-crosslinked reaction conditions. Adsorption study towards aniline showed that the three resins, ST-DVB-WH5, ST-DVB-WH6, and ST-DVB-WH7, prepared at different temperatures, and which had nearly identical static adsorption capacity, displayed great disparity in kinetic behavior. The rate constant of ST-DVB-WH7 by the pseudo-first-order model was 1.50 and 1.19 times higher than that of ST-DVB-WH5 and ST-DVB-ST-DVB-WH6. Further analysis of the diffusion model showed that the three resins exhibited different diffusion rates due to the difference in oxygen content and pore structure of each resin. The results showed that the adsorption capacity was mainly decided by the pore volume within 1.14 and 3.42 nm and the adsorption rate was mainly decided by the oxygen content of the resin. In addition, as the best synthetic resin for aniline adsorption, the equilibrium adsorption capacity of ST-DVB-WH7 was 1.57 times and 1.44 times higher than that of H-103 and NKA-II, respectively. [ABSTRACT FROM AUTHOR]

The selective chloromethylenation of functionalized esters using chloroacetic acid (CA) and LiHMDS (HMDS=hexamethyldisilazide) in a continuous‐flow setup is reported. This Claisen homologation is for the first time extended to bis‐chloromethylenation using dichloroacetic acid (DCA), thus giving access to under‐explored α,α′‐bis‐chloroketones. The use of flow conditions enables efficient generation and reaction of the unstable chloroacetate dianion intermediates, leading to unprecedented mild and scalable reaction conditions at an economical reagent stoichiometry (−10 °C, <1 min, 1.0–2.4 equiv dianion). The clean reaction profiles allow subsequent use of the unpurified crude products, which is demonstrated in the synthesis of various heterocycles of broad interest. Furthermore, we report a novel, catalyst‐free substitution of the obtained monochloro ketone products with (hetero)aryl zinc enolates to give valuable 1,4‐diketones. A highly chemoselective chloromethylenation of functionalized esters using (di)chloroacetic acid and LiHMDS was carried out in a continuous‐flow setup under unprecedented mild and scalable conditions. The resulting (crude) products were reacted either in cyclcocondensations or a novel catalyst‐free substitution reaction to give valuable 1,4‐diketones. [ABSTRACT FROM AUTHOR]

The alkene cyclopropanation with chloromethyl silicate as a methylene transfer reagent has been accomplished via visible‐light‐mediated redox‐neutral catalysis. This method features broad functional group tolerance and mild conditions. In addition to α‐substituted vinylphosphonates, a range of Michael acceptors including α,β‐unsaturated acrylate, ketone, amide and sulfone are suitable substrates for this photocatalytic cyclopropanation. An application of this protocol to the cyclopropanation of estrone derivative is also presented. [ABSTRACT FROM AUTHOR]

Cross‐linking of phosphoric acid doped polybenzimidazole membranes as fuel cell electrolytes represents an attractive approach to improving the mechanical robustness at a high acid loading. Numerous cross‐linking concepts have been reported in the literature, but a deeper understanding of how the cross‐linking chemistry affects the physicochemical properties of the membrane and its fuel cell performance and durability remains to be assessed. In this work, a series of cross‐linked membranes are prepared using cross‐linking agents of different regio‐chemistry and steric nature. It is shown, that the nature of the cross‐linking agent has a large impact on the effective degree of cross‐linking, which in turn determines the acid doping characteristics and ultimately the fuel cell performance and acid retention during long‐term operation. [ABSTRACT FROM AUTHOR]

The title compound 8-chloro-3-((4-cyanobenzyl)thio)-[1,2,4]triazolo[4,3-a]pyridine is prepared from 1- cyano-4-(chloromethyl)benzene and 8-chloro-[1,2,4]triazolo[4,3-a]pyridine-3(2H)-thione in the presence of NaOH, and its structure is determined by the X-ray diffraction analysis. The crystals are monoclinic, space group P2(1)/n, with a = 14.018(8) Å, b = 4.096(2) Å, c = 22.974(12) Å, β = 99.759(9)°, V = 1300.1(12) Å3, and Z = 4, the final R = 0.0343 and wR = 0.0788 for 2505 observed reflections with I > 2σ(I). The preliminary biological test shows that the title compound has activities against Stemphylium lycopersici (Enjoji) Yamamoto, Fusarium oxysporum. sp. cucumebrium, and Botrytis cinerea with inhibitory to be 51.19%, 62.02%, 15.56% respectively. [ABSTRACT FROM AUTHOR]

Soil‐living microbes are an important resource for the discovery of new natural products featuring great structural diversity that are reflective of the underlying biosynthetic pathways as well as incorporating a wide range of intriguing small‐molecule building blocks. We report here the full structural elucidation, total synthesis, and biosynthesis of chloromyxamides, a new class of tetrapeptides that display an unprecedented 6‐chloromethyl‐5‐methoxypipecolic acid (CMPA) substructure. Chemical synthesis—including an approach to access the CMPA unit—was pursued to confirm the structure of the chloromyxamides and enabled determination of the absolute configuration in the CMPA ring. A model for the nonribosomal assembly of chloromyxamides was devised on the basis of the combined evaluation of the biosynthetic gene cluster sequence and the feeding of stable isotope‐labeled precursors. This provided insight into the formation of the various chloromyxamide derivatives and the biogenesis of the CMPA unit. Family matters: A family of chlorinated tetrapeptides called chloromyxamides have been discovered from myxobacteria and their structure fully elucidated. The study features a concise chemical synthesis and a model for chloromyxamide biosynthesis, underpinned by stable isotope labeling and tandem‐MS experiments. [ABSTRACT FROM AUTHOR]

6,7-Dichloro-2-methyl-5,8-quinolinedione was investigated using different experimental methods as well as a variety of various quantum chemical calculations in order to characterize its molecular structure as a potential anticancer active compound. We used X-ray diffraction, IR spectrum analysis supplemented by the density functional theory (DFT) calculations, molecular electrostatic potential (MEP) and molecular orbital (HOMO, LUMO) analyses. The analyzes were carried out with respect to 6,7-dichloro-5,8-quinolinedione. It was found that introduction of the methyl group at the C-2 position distinctly affected the crystal structure, formation of H-bonds and the carbonyl stretching IR bands of the title compound. The molecular electrostatic potential map showed how the electrophilic and nucleophilic regions are located in the molecule. The intra- and intermolecular bonding and interaction between bonds were interpreted using the Natural Bond Orbital (NBO) and Natural Localized Molecular Orbital (NLMO) analysis. The title compound was tested for its anticancer activity in vitro against the several human cancer cell lines. 6,7-Dichloro-2-methyl-5,8-quinolinedione showed a higher cytotoxic activity against cancer cell lines containing a higher level of NQO1 enzyme, like melanoma (C-32) and breast (MCF-7) cancer cell lines. The molecular docking was used to examine the probable interaction between the molecule of the tested compound and the NQO1 enzyme. The analysis showed that the 5,8-quinolinedione moiety of the title compound formed a hydrophobic interaction with phenylalanine (Phe 178), tyrosine (Tyr 126 and Tyr 128) and FAD cofactor. [ABSTRACT FROM AUTHOR]

Lipoprotein lipase (LPL) catalyzes the breakdown of circulating triglycerides in muscle and fat. LPL is inhibited by several proteins, including angiopoietin-like 4 (ANGPTL4), and may be cleaved by members of the proprotein convertase subtilisin/kexin (PCSK) family. Here, we aimed to investigate the cleavage of LPL in adipocytes by PCSKs and study the potential involvement of ANGPTL4. A substantial portion of LPL in mouse and human adipose tissue was cleaved into N- and C-terminal fragments. Treatment of different adipocytes with the PCSK inhibitor decanoyl-RVKR-chloromethyl ketone markedly decreased LPL cleavage, indicating that LPL is cleaved by PCSKs. Silencing of Pcsk3/furin significantly decreased LPL cleavage in cell culture medium and lysates of 3T3-L1 adipocytes. Remarkably, PCSK-mediated cleavage of LPL in adipocytes was diminished by Angptl4 silencing and was decreased in adipocytes and adipose tissue of Angptl4-/- mice. Differences in LPL cleavage between Angptl4-/- andWTmice were abrogated by treatment with decanoyl-RVKR-chloromethyl ketone. Induction of ANGPTL4 in adipose tissue during fasting enhanced PCSK-mediated LPL cleavage, concurrent with decreased LPL activity, in WTbut not Angptl4-/-mice. In adipocytes, after removal of cell surface LPL by heparin, levels of N-terminal LPL were still markedly higher in WT compared with Angptl4-/- adipocytes, suggesting that stimulation of PCSK-mediated LPL cleavage by ANGPTL4 occurs intracellularly. Finally, treating adipocytes with insulin increased full-length LPL and decreased N-terminal LPL in an ANGPTL4-dependent manner. In conclusion, ANGPTL4 promotes PCSK-mediated intracellular cleavage of LPL in adipocytes, likely contributing to regulation of LPL in adipose tissue. Our data provide further support for an intracellular action of ANGPTL4 in adipocytes. [ABSTRACT FROM AUTHOR]

This work deals the synthesis of aryl azides catalyzed by heterogeneous copper (II) complex of 3,5–bis (2–benzothiazolyl) pyridine, [Cu (II)(BTP)(OTf)2], immobilized on chloromethylated polystyrene, [Cu (II)(BTP)(OTf)2]@CMP. The prepared catalyst was characterized by different analytical techniques such as X‐ray diffraction (XRD), thermogravimetric analysis (TGA), field emission scanning electron microscopy (SEM), energy dispersive X–ray spectroscopy (EDX), elemental analysis, and FT‐IR and UV–Vis spectroscopic methods. This catalytic system showed excellent activity in the synthesis of aryl azides by the reaction of aryl halides with sodium azide in the presence of catalytic amounts of [Cu (II)(BTP)(OTf)2]@CMP. Moreover, this unique catalyst could be recovered easily and reused several times without any considerable loss of its catalytic activity. [ABSTRACT FROM AUTHOR]

1-Chloromethyl- and 1-dichloromethyl-3,3-dialkyl-3,4-dihydroisoquinolines were synthesized via cyclo-condensation of dialkylbenzylcarbinols with chloroacetonitrile or dichloroacetonitrile. Their hydrochlorides were tested for antiarrhythmic, anticonvulsant, and analgesic activity. Water-soluble 1-chloromethylisoquinoline hydrochlorides showed antiarrhythmic activity with a maximum antiarrhythmic index of 14.8. These same compounds were active against corazole-induced convulsions. 1-Dichloromethylisoquinolines had analgesic effects comparable with that of metamizole sodium. [ABSTRACT FROM AUTHOR]

Reaction of O -trimethylsilyl ( O -TMS) derivatives of α-dimethylamino ketones with chloro(chloromethyl)dimethylsilane led to the formation of six-membered heterocyclic compounds with tetracoordinated silicon atom - 3,4-dihydro-2 H -1,4,2-oxazasilin-4-ium chlorides. The exchange reactions of 2,2,4,4-tetramethyl-6-phenyl-3,4-dihydro-2 H -1,4,2-oxazasilin-4-ium chloride were examined with Me 3 SiI and NaBPh 4 and the corresponding iodide or tetraphenylborate of 2,2,4,4-tetramethyl-6-phenyl-3,4-dihydro-2 H -1,4,2-oxazasilin-4-ium were isolated. 2,2,4,4-Tetramethyl-6-phenyl-3,4-dihydro-2 H -1,4,2-oxazasilin-4-ium chloride easy reacts with MeOH to give N -((methoxydimethylsilyl)methyl)- N , N -dimethyl-2-oxo-2-phenylethanaminium chloride. The structure of synthesized compounds 10 – 15 was proved by multinuclear NMR spectroscopy, 11 was also characterised by X-ray crystallography. [ABSTRACT FROM AUTHOR]

Legumain is a dual-function protease-peptide ligase whose activities are of great interest to researchers studying plant physiology and to biotechnological applications. However, the molecular mechanisms determining the specificities for proteolysis and ligation are unclear because structural information on the substrate recognition by a fully activated plant legumain is unavailable. Here, we present the X-ray structure of Arabidopsis thaliana legumain isoform γ (AtLEGγ) in complex with the covalent peptidic Ac-YVAD chloromethyl ketone (CMK) inhibitor targeting the catalytic cysteine. Mapping of the specificity pockets preceding the substrate-cleavage site explained the known substrate preference. The comparison of inhibited and free AtLEGγ structures disclosed a substrate-induced disorder-order transition with synergistic rearrangements in the substrate-recognition sites. Docking and in vitro studies with an AtLEGγ ligase substrate, sunflower trypsin inhibitor (SFTI), revealed a canonical, protease substrate-like binding to the active site-binding pockets preceding and following the cleavage site. We found the interaction of the second residue after the scissile bond, P2'-S2', to be critical for deciding on proteolysis versus cyclization. cis-trans-Isomerization of the cyclic peptide product triggered its release from the AtLEGγ active site and prevented inadvertent cleavage. The presented integrative mechanisms of proteolysis and ligation (transpeptidation) explain the interdependence of legumain and its preferred substrates and provide a rational framework for engineering optimized proteases, ligases, and substrates. [ABSTRACT FROM AUTHOR]

Anabolic androgenic steroids (AAS) are misused very frequently in sport competitions as performance enhancing agents. One of the doping compounds that has been detected with increased frequency in the last few years is dehydrochloromethyltestosterone (DHCMT, 4-chloro-17β-hydroxy-17α-methylandrosta-1,4-dien-3-one; brand name Oral Turinabol). The long-term DHCMT metabolite 20βOH-NorDHCMT (4-chloro-17β-hydroxymethyl-17α-methyl-18-norandrosta-1,4,13-trien-3-one) was reported earlier to be detectable in urine samples for more than 22 days after DHCMT administration; however, purified reference material was not available so far. In this study we demonstrate a successful combination of Wagner-Meerwein rearrangement of DHCMT to NorDHCMT (4-chloro-17,17-dimethyl-18-norandrosta-1,4,13-trien-3-one) and subsequent whole-cell biotransformation with a recombinant fission yeast strain expressing the human cytochrome P450 enzyme (CYP or P450) CYP21A2 for the synthesis of mg amounts of this metabolite. It was then used as reference for the analysis of a post administration urine of DHCMT. The availability of this reference compound will provide an incontestable proof for DHCMT abuse. [ABSTRACT FROM AUTHOR]

Abstract: Treatment of 2-(chloromethyl)-pyridine derivatives 3,5-dimethyl-4-(alkoxy)-2-(chloromethyl)-pyridine hydrochloride (alkoxy = methoxy, 1; ethoxy, 2) with 1-(4-chloro-phenyl)imidazole-2-thione in the presence of sodium methoxide afforded the corresponding methylsulphinyl derivatives 3,5-dimethyl-[4-(alkoxy)-2-pyridinyl]-methylthio-1-(4-chloro-phenyl)-imidazole (alkoxy = methoxy, 3; ethoxy, 4). Similarly, reaction of 1 or 2 with 4,6-dimethyl-pyrimidine-2-thiol gave the methylsulphinyl derivatives 3,5-dimethyl-[4-(alkoxy)-2-pyridinyl]-methylthio-4,6-dimethyl-pyrimidine (alkoxy = methoxy, 5; ethoxy, 6). While reaction of 5 with CuCl2·2H2O in methanol produced a square-planar copper(II) complex, trans-bis{3,5-dimethyl-[4-(methoxy)-2-pyridinyl]-methylthio-4,6-dimethyl-pyrimidine}-dichloro-copper(II) (7). The crystal structures of 1, 2, 4⋅HCl⋅2H2O, and 7, along with their spectroscopic properties are reported. The weak hydrogen-bonding interactions exist in compounds 1, 2, and 4⋅HCl⋅2H2O. Compound 1 crystallizes in the monoclinic space group P21/c with a = 6.074(11), b = 19.88(4), c = 9.230(16) Å, β = 99.67(4)°, and Z = 4. Compound 2 crystallizes in the monoclinic space group P21/n with a = 10.0103(15), b = 7.9905(12), c = 15.120(2) Å, β = 93.924(2), and Z = 4. The unit cells of both 4⋅HCl⋅2H2O and 7 have triclinic P-1 symmetry with the cell parameters a = 7.492(8), b = 10.170(12), c = 15.723(18) Å, α = 77.159(15)°, β = 91.113(13)°, γ = 81.194(16)°, and V = 1152(2) Å3 for 4⋅HCl⋅2H2O and a = 10.526(2), b = 12.936(2), c = 14.455(3) Å, α = 107.929(2)°, β = 93.686(2)°, γ = 104.095(3)°, and V = 1734.3(6) Å3 for 7.Graphical Abstract: Interaction of 3,5-dimethyl-[4-(methoxy)-2-pyridinyl]-methylthio-4,6-dimethyl-pyrimidine and CuCl2·2H2O in methanol resulted in the formation of a square-planar copper(II) complex, trans-bis{3,5-dimethyl-[4-(methoxy)-2-pyridinyl]-methylthio-4,6-dimethyl-pyrimidine}-dichloro-copper(II), which was structurally characterized. [ABSTRACT FROM AUTHOR]

In the present research, we report the synthesis and in vitro antimicrobial activity of a new series of novel quinazolino-thiadiazoles as fused pharmacophore (3–20). In general, the results of the in vitro antibacterial activity are encouraging, as out of 18 compounds tested, Compounds 3 and 8 with a 4-chlorophenyl and 4-nitro phenyl at C-2 of thiadiazole and chloromethyl substituent at C-2 of quinazolinone displayed a broad spectrum antimicrobial activity against all the strains, while compounds 13 and 16 again with a 4-chlorophenyl and 4-nitrophenyl at C-2 of thiadiazole and ethyl substituent at C-2 of quinazolinone showed the same potency but with a narrower spectrum (Bacterial and Fungal strains) with MIC values of 62.5 µg/ml. The structures of the compounds were confirmed by IR, 1 H NMR, 13 C NMR and Mass analysis. It is worth to mention that the combination of two biologically active moieties quinazoline and thiadiazole profoundly influences the biological activity. [ABSTRACT FROM AUTHOR]

Self-cross-linked 4,4′-bis(chloromethyl)-1,1′-biphenyl (BCMBP) polymers with tailored pore size distribution (PSD) and average pore width (W avg ) were synthesized via the Friedel-Crafts reaction in 1,2-dichloroethane (DCE) with reactive (benzene) or non-reactive (hexane and cyclohexane) co-solvents. Compared to using only DCE, W avg increases (up to 450%) with increasing benzene:DCE ratio due to decreases in cross-linking degree. Hexane and cyclohexane induce phase separation and co-solvent trapping in developing polymers, changing PSD and W avg without altering cross-linking degree. Findings provide a simple technique to synthesize hyper-cross-linked polymers with user-defined PSDs. [ABSTRACT FROM AUTHOR]

Crystals of bis-chloromethyl-phosphinic acid ((CH2Cl)2POOH) are studied by attenuated total reflection (ATR) and Raman spectroscopy supported by X-Ray diffraction. The bands recorded in the ATR and in Raman spectra have the same wavenumbers within experimental uncertainty. It is in agreement with the X-Ray diffraction results which show that the molecules in crystals form infinite chains through hydrogen bonds and there is no center of inversion. The parameters of the unit cell, the bond lengths and angles, and the distance between two oxygen atoms in hydrogen bond bridges are determined. The spectral features and the intermolecular distance between oxygen atoms are characteristic for a strong hydrogen bonded system. [ABSTRACT FROM AUTHOR]

Abstract: Two chloromethyl phenylcarbamate‐based chiral stationary phases, one containing an amylose‐type chiral selector (Lux Amylose 2, from Phenomenex) and the other a cellulose‐type one (Lux Cellulose‐4, from Phenomenex), were successfully used for the chiral resolution of three helical chromenes featuring a helicene‐like structure. The compound bearing a phenyl substituent on the helicene‐like structure was enantioresolved at 25°C with Lux Cellulose‐4 and a n‐hexane/1‐propanol 99:1 v/v eluent. With a n‐hexane/2‐propanol 99.8:0.2 v/v mobile phase, the same column (operated at 35°C) provided the separation of the four isomers of the compound having a hexyl residue on the helicene‐like motif and an additional asymmetric carbon. Lux Amylose‐2 was necessary for the enantioseparation of the compound having the sole hexyl residue on the helical scaffold. For the last compound a n‐hexane/2‐propanol 99.8:0.2 v/v eluent was used, and the column temperature was fixed at 5°C. The enantiomer elution order was appraised by using electronic circular dichroism and theoretical calculations. Notably, different thermodynamics of retention and enantioseparation were observed for molecules with pronounced structural similarity, that is, the enantiomer pairs of the compound containing the additional asymmetric carbon atom. Indeed, both entropically and enthalpically controlled adsorption and separation processes were observed. [ABSTRACT FROM AUTHOR]

Abstract: It is shown that (2E,6E)‐2,6‐bis(chloromethylidene)‐N‐organyl thiomorpholine 1‐oxides and (2E,6E)‐2,6‐bis(chloromethylidene)‐1,4‐dithiane 1,1,4,4‐tetraoxides, unlike unoxidized analogs, (2E,6E)‐2,6‐bis(chloromethylidene)‐N‐organyl thiomorpholines, and (2E,6E)‐2,6‐bis(chloromethylidene)‐1,4‐dithiane, easily undergo stereoselective nucleophilic vinylic substitution reactions with such chalcogen‐containing nucleophiles as sodium 1‐butanethiolate, arenethiolates, and benzeneselenolate to afford previously unknown (2E,6E)‐2,6‐bis(organylchalogenylmethylidene)‐N‐organyl thiomorpholine 1‐oxides and (2E,6E)‐2,6‐bis(organylchalogenylmethylidene)‐1,4‐dithiane 1,1,4,4‐tetraoxides in high yields. The structures of the heterocycles formed have been confirmed by 1H, 13C NMR, and mass spectrometry data. [ABSTRACT FROM AUTHOR]

Formaldehyde dehydrogenase (FaldDH) is used as a catalyst to reduce formate to formaldehyde in a cascade reaction to convert CO 2 to methanol. This enzyme, however, has low activity and is sensitive to substrate/product concentration and pH. To improve the performance of FaldDH, it can be immobilized through physical adsorption in siliceous mesostructured cellular foams (MCF), which physical properties are suitable for the immobilization of large molecules as FaldDH (molecular size of 8.6 × 8.6 × 19 nm). In this work two MCF materials were synthesized: MCF1 with a pore size of 26.8 nm and window size of 10.5 nm; and MCF2 with a pore size of 32.9 nm and window size of 13.0 nm. The surfaces of the materials were functionalized with octyl, mercaptopropyl or chloromethyl groups. FaldDH was successfully immobilized inside all the materials, yielding enzyme loadings of about 300 mg g ‐1 in MCF1 and more than 750 mg g −1 in MCF2. However, the enzyme was inactive upon immobilization on MCF1, whereas on MCF2 the enzyme retained its catalytic activity presumably owing to the larger pores of this material and the need for the enzyme to undergo configurational changes during the reaction. Using MCF2 functionalized with mercaptopropyl groups the activity of FaldDH was enhanced beyond that of the free enzyme. Additionally, low leakage of the enzyme from the MCF2 was observed during the reactions. Thus, tailored MCF is a highly attractive material for employment of the FaldDH enzyme. [ABSTRACT FROM AUTHOR]

In the superbase KOH/H 2 O/toluene/phase-transfer catalyst system, 2-picolyl chloride, generated in situ from 2-(chloromethyl)pyridine hydrochloride, reacts with elemental phosphorus at 65–95 °C for 3 h to afford tris(2-picolyl)phosphine oxide in 50% yield. Single crystal X-ray analysis of the latter revealed one polymorph form of this tertiary phosphine oxide. [ABSTRACT FROM AUTHOR]