Search

A high surface acidic ZrO2 nanoparticle was prepared using glucose as a non-toxic reducing agent. Palladium (Pd) nanoparticles in the range of 1–2 nm are grafted in in-situ as well as ex-situ via urea deposition over pre-synthesized ZrO2 nanoparticles. Both methods are found to be useful for the one-pot transformation of glucose to HMF, and their catalytic activities towards selective production of HMF are found to be strongly dependent on the particle size and nature of acidic sites. A linear-type activity trend is observed with Pd loading in reference to the HMF selectivity and presents the best catalytic performance. The activation energy and turnover frequency (TOF) of the 1–2 nm NP catalyst are further calculated to be 44.1 kJ mol−1 and 6.011 molHMF·molPd−1·h−1, respectively. Characterization of the spent catalysts indicates that smaller-sized NPs face severe agglomeration, resulting in poor stability and activity. Hence, the high catalytic performance can be attributed to the balance between Bronsted and Lewis acid sites, in combination with Pd species intrinsic activity. Due to their improved activity and stability, 2Pd–ZrO2in-situ exhibits 55% glucose conversion with 74.0% of HMF selectivity after 3h of reaction at 160 °C.

The Hydroxymethyl (•CH2OH) radical is an important intermediate species in both atmosphere and combustion reaction systems. The rate coefficients for •CH2OH + 3O2 and (CH2OH + 3O2 (+H2O) reactions were calculated using Rice−Ramsperger−Kassel−Marcus (RRKM)/master equation (ME) simulation and canonical variational transition state theory (CVT) between the temperature range of 200 to 1500 K based on the potential energy surface constructed using CCSD(T)//ωB97XD /6-311++G(3df,3pd). The results show that •CH2OH + 3O2 leads to form CH2O and HO2 in the temperature 1000K). When water molecule added to the reaction favored the formation of CH2O and HO2 in all the temperature. The calculated rate coefficient for the •CH2OH + 3O2 (2.8×10-11 cm3 molecule-1 s-1 at 298K) is in good agreement with the previous experimental values (~1×10-11 cm3 molecule-1 s-1 at 298K). The rate coefficients for the water-assisted reaction (2.4×10-16 cm3 molecule-1 s-1 at 1000K) is at least 3-4 order magnitude smaller than the water-free reaction (6.2×10-12 cm3 molecule-1 s-1 at 1000 K). This result is consistent with the similar types of reaction system. Our calculations also predict that the effect of a single water molecule favors the formation of CH2O in the combustion condition however, the water-free reaction favors the formation of CH2O in the atmospheric condition. The current study helps to understand how a single water molecule changes the reaction mechanism and chemical kinetic behaviour under atmospheric and combustion conditions.

We report herein the development of α-borylmethyl-(Z)-crotylboronate reagent and the application in highly stereo- and enantioselective syntheses of (E)-δ-hydroxymethyl-syn-homoallylic alcohols. Starting from 1,4-pentadiene, α-borylmethyl-(Z)-crotylboronate was synthesized in two steps with high Z-selectivity and enantioselectivity. Subsequent aldehyde allylboration with the developed boron reagent gave highly enantioenriched (E)-δ-hydroxymethyl-syn-homoallylic alcohols upon oxidative workup.

Beta-zeolite supported ruthenium catalysts for reductive amination of 5-hydroxymethyl-2-furaldehyde (HMF) with an aqueous solution of ammonia (NH3 aq.) and molecular hydrogen (H2) are examined to synthesize the corresponding primary amine of 5-aminomethyl-2-furylmethanol (FAA). Various SiO2/Al2O3 (Si/2Al) ratios of the beta-zeolite support were used to prepare the Ru-based catalysts. It was observed that the Si/2Al ratio was contributed to the catalytic activity, and the Si/2Al = 150 of beta-zeolite was found to be the most active for Ru catalyzed reductive amination of HMF, affording ca. 70% yield. Characterization techniques were taken to analysis the factors that influence the reactivity of catalysts, and which revealed that not only the ruthenium nanoparticle size but also the ratio of RuO2 against metallic Ru species were crucial factors for the reactivity of reductive amination of HMF to FAA.

A regioselective method for the synthesis of 1-(hydroxymethyl)-2,3-dihydropyrrolo[1,2-a]quinazolin-5(1H)-ones – close structural analogs of naturally occurring vasicinone alkaloids – is described. The procedure is based on PIFA-initiated oxidative 5-exo-trig cyclization of 2-(3-butenyl)quinazolin-4(3Н)-ones, in turn prepared by thermal cyclocondensation of the corresponding 2-(pent-4-enamido)benzamides. The products obtained have a good natural product likeness (NPL) score and therefore can be useful for the design of natural product-like compound libraries.

Herein, a tandem approach that allows rapid access to the benzomorpholine scaffold is reported. This operationally simple method allows for valuable heterocycles to be isolated in moderate to high yields. The overall transformation consists of an initial C-N coupling, demonstrated using traditional Ullmann or Buchwald-Hartwig conditions, followed by an in situ oxetane ring opening. A range of functionality is tolerated on the aryl ring, and the cyclization exposes a pendant hydroxymethyl substituent, providing opportunities for further functionalization.

We present the results of classical and QM/MM simulations for the inhibition of SARS‐CoV‐2 3CL protease by a hydroxymethylketone inhibitor, PF‐00835231. In the noncovalent complex the carbonyl oxygen atom of the warhead is placed in the oxyanion hole formed by residues 143 to 145, while P1–P3 groups are accommodated in the active site with interactions similar to those observed for the peptide substrate. According to alchemical free energy calculations, the P1′ hydroxymethyl group also contributes to the binding free energy. Covalent inhibition of the enzyme is triggered by the proton transfer from Cys145 to His41. This step is followed by the nucleophilic attack of the Sγ atom on the carbonyl carbon atom of the inhibitor and a proton transfer from His41 to the carbonyl oxygen atom mediated by the P1′ hydroxyl group. Computational simulations show that the addition of a chloromethyl substituent to the P1′ group may lower the activation free energy for covalent inhibition, Multiscale simulations unveil the binding and reaction mechanism of the SARS‐CoV‐2 main protease inhibitor, PF‐00835231 inhibitor. This compound contains a hydroxymethyl group that plays a relevant role in the formation of the noncovalent and covalent complexes. In silico modifications show a possible strategy for the design of new inhibitors.

Derived from the most abundant natural polymer, cellulose nanocrystal materials have attracted attention in recent decades due to their chemical and mechanical properties. However, still unclear is the influence of different exposed facets of the cellulose nanocrystals on the physicochemical properties. Herein, we first design cellulose II nanocrystals with different exposed facets, the hydroxymethyl conformations distribution, hydrogen bond (HB) analysis, as well as the relative structural stability of these models (including crystal facets {A, B, O} and Type-A models vary in size) are theoretically investigated. The results reveal that the HB network of terminal anhydroglucose depends on the adjacent chain’s contact sites in nanocrystals exposed with different facets. Compared to nanocrystals exposed with inclined facet, these exposed with flat facet tend to be the most stable. Therefore, the strategy of tuning exposed crystal facets will guide the design of novel cellulose nanocrystals with various physicochemical properties.

Green fuel: The electrohydrodimerization of biomass-based 5-hydroxymethlfurfural to the fuel precursor 5,5’-bis(hydroxymethyl)hydrofuroin on carbon electrodes is a promising pathway towards renewable fuels. The effect of the hybridization of the carbon electrode on the HMF electroreduction activity and selectivity is studied, as well as the influence of applied potential and initial HMF concentration. The electrochemical conversion of biomass-based compounds to fuels and fuel precursors can aid the defossilization of the transportation sector. Herein, the electrohydrodimerization of 5-hydroxymethylfurfural (HMF) to the fuel precursor 5,5’-bis(hydroxymethyl)hydrofuroin (BHH) was investigated on different carbon electrodes. Compared to boron-doped diamond (BDD) electrodes, on glassy carbon (GC) electrodes a less negative HMF reduction onset potential and a switch in product selectivity from BHH to the electrocatalytic hydrogenation product 2,5-di(hydroxymethyl)furan (DHMF) with increasing overpotential was found. On BDD, the electrohydrodimerization was the dominant process independent of the applied potential. An increase in the initial HMF concentration led to suppression of the competing hydrogen evolution reaction and DHMF formation, resulting in higher BHH faradaic efficiencies. In contrast, BHH selectivity decreased with higher initial HMF concentration, which was attributed to increased electrochemically induced HMF degradation. Finally, it was demonstrated that even a simple graphite foil can function as an active HMF electroreduction catalyst.

Digestive tract disorders, especially gastric disorders, are often experienced by people. One drug to treat this disorder has a mechanism of blocking the H2 receptor. This research was conducted to find compounds from C.verum which have the stability of bind to H2 receptors. The method used is protein modeling with swiss-model, docking with PLANTS (CHEMPLP) and activity prediction. The test results obtained that the docking score was ?- amorphene (-65,79), ?-bergamotene (-65,48), ?-copaene (-66,62), ?-cubebene (-66,46), Cadinene (-64 , 79), Camphor (-52.15), Caryophyllene (-62.61), Cinnamaldehyde (-68.17), Epicatechin (-80.43), Ergosterol (-85.24), Eugenol (-67.35), Hydrocinnamaldehyde (-65,53), Quercetin (-74,38), Protocatechuic acid (-71,49), Stigmasterol (-88,88), 4- (2,3-dihydro-3- (hydroxymethyl) - 5- (3-hydroxypropyl) -7- (methoxy) benzofuranyl] -2-methoxyphenyl (-85,29). Combined with the probability activity of compounds that have the potential to be further developed are Epicatechin and urolignoside.

Glycation and caramelization reactions in malt lead to the formation of 1,2-dicarbonyl compounds, which come in contact with yeast during fermentation. In the present study, the metabolic fate of 5-hydroxymethylfurfural (HMF) and 1,2-dicarbonyl compounds (3-deoxyglucosone, 3-deoxygalactosone, 3-deoxypentosone, 3,4-dideoxyglucosone-3-ene) was assessed in the presence of Saccharomyces cerevisiae. HMF is degraded very fast by yeast with the formation of 2,5-bis(hydroxymethyl)furan (BHMF). By contrast, only 7-30% of 250 μM dicarbonyl compounds is degraded within 48 h. The respective deoxyketoses, 3-deoxyfructose (3-DF), 3-deoxytagatose, 3-deoxypentulose, and 3,4-dideoxyfructose, were identified as metabolites. While 17.8% of 3-deoxyglucosone was converted to 3-deoxyfructose, only about 0.1% of 3-deoxypentosone was converted to 3-deoxypentulose during 48 h. Starting with the parent dicarbonyl compounds, the synthesis of all deoxyketose metabolites was achieved by applying a metal-catalyzed reduction in the presence of molecular hydrogen. In a small set of commercial beer samples, BHMF and all deoxyketoses were qualitatively detected. 3-DF was quantitated in the four commercial beer samples at concentrations between 0.4 and 10.1 mg/L.

The Maillard reaction, a spontaneous 'one pot' reaction between amino acids and reducing sugars that occurs at low reactant concentrations and low temperatures, is a good candidate for having played a role in the origin of life on the Earth. In view of the probability that RNA and DNA were preceded by an evolutionary forerunner with a more straightforward prebiotic synthesis, it is a testament to the prescience of Oro and colleagues that, in 1975, they drew attention to the Maillard reaction, in particular evidence that melanoidin polymers (the end-product of the reaction) contain '…heterocyclic nitrogen compounds similar to the nitrogenous bases' (Nissenbaum in J Mol Evol 6:253-270, 1975). Indeed, reports of the Maillard reaction product, 2-Acetyl-6-(Hydroxymethyl)-5,6-Dihydro-4H-Pyridinone (AHDP), with a structure reminiscent of the pyrimidine nucleobase uracil, suggest the Maillard reaction might have played a key role in the synthesis of components of a proto-RNA polymer, with AHDP and two structurally related products predicted to be similar to uracil in the latter's ability to form non-standard base pair interactions. It is possible that the primary function of these interactions was to allow molecules such as AHDP to separate out of the prebiotic chemical clutter. If this were the case, catalysis, and coding-made possible by the polymerization of proto-nucleoside monomers into linear sequence strings-would have been evolving properties.

The impact of lithium chloride inorganic salt (LiCl) on the response of radiated N-(Hydroxymethyl) acrylamide (NHMA) polymer gel dosimeters was presented in this article. The NHMA-LiCl polymer dosimeters were positioned in a cubic water-phantom and then irradiated by a linac to different dose ranging from 0 to 10 Gy. The response of gel to X-ray radiation was evaluated using NMR spin–spin relaxation rate (R2 = 1/T2). Linearity relationship of dose–response s were obtained in the dose-range of 0–6 Gy. The polymer showed a significant increase in dose-sensitivity (about 50%) when LiCl concentration was increased from 0 to 2.1wt% in the linearity region of 0–6 Gy. The dependency of irradiated gel on the dose rate and the photon beam energy were not observed by adding LiCl over the range studied (less than 5%). The R2 values were decreased with increasing the scanning temperature. The gel was fairly stable after four days of irradiation. The LiCl acts as an excellent sensitizer to the polymerization of irradiated gel dosimeters.

A facile and environmentally benign access to N-aryl/alkyl-4H-benzoxazin-2-amines is achieved from 1-[2-(hydroxymethyl)phenyl/alkyl]-3-phenylthioureas under transition-metal-free conditions. The conversions occur smoothly in the presence of a catalytic amount of molecular iodine and hydrogen peroxide as the oxidant in tetrahydrofuran at room temperature to afford moderate to good yields (28–90%) of the desired products within 2 hours. This method reports the first examples of the catalytic transformations of 1-[2-(hydroxymethyl)phenyl/alkyl]-3-phenylthioureas into N-aryl/alkyl-4H-benzoxazin-2-amines based on desulfurative cyclization.

The nonstopping increment of atmospheric carbon dioxide (CO2) concentration keeps harming the environment and human life. The traditional concept of carbon capture and storage (CCS) is no longer sufficient and has already been corrected to carbon capture, utilization, and storage (CCUS). CCUS involves significant CO2 utilization, such as cyclic carbonate formation, for its cost effectiveness, less toxicity, and abundant C1 synthon in organic synthesis. However, the high thermodynamic and kinetic stability of CO2 limits its applications. Herein, we report a mild, efficient, and practical catalyst based on abundant, nontoxic CaI2 in conjunction with biocompatible ligand 1,3-bis[tris(hydroxymethyl)-methylamino]-propane (BTP) for CO2 fixation under atmospheric pressure with terminal epoxides to give the cyclic carbonates. The Job plot detected the 1:1 Ca2+/BTP binding stoichiometry. Furthermore, formation of a single crystal of the 1:1 Ca2+/BTP complex was confirmed by single-crystal X-ray crystallography. The bis(cyclic carbonate) products exhibit potentials for components in the non-isocyanate polyurethanes (NIPUs) process. Notably, this protocol shows attractive recyclability and reusability.

In this work, a hyperbranched polymer (PDBM) was prepared via a simple “one-pot” reaction process using diethyl bis(hydroxymethyl)malonate as the centronucleus. Its structure and thermal stability were characterized by 1H NMR, FT-IR and TG-DTG. The factors affecting the demulsifying performance such as the dosage of demulsifier, standing time and salinity were systematically studied in diesel-in-water (O/W) emulsion at 25 ℃. After adding 100 mg/L of PDBM and standing for 60 min at 25 ℃, the light transmittance of separated water (TSW) could up to 91.4%. In addition, the properties of interface and surface, zeta potential, microscopic images and droplet size distribution provided the clues for possible demulsifying mechanism. To further exploring the mechanism, the polymer (PDM) with a similar structure was also synthesized by the same method. It showed that the hydroxyl groups at the centronucleus of PDBM played a key role in the demulsification process of the O/W emulsion.

Biomass-derived monomers have received growing attention from sustainable polymer industry. Particularly, diol compounds can be formed from furfural (FAL) and 5-hydroxymethylfurfural (HMF). Herein, the mesoporous Cu–Al2O3 catalyst (meso-CuA) prepared by solvent-deficient precipitation was evaluated to be efficient in selective hydrogenation of FAL and HMF to furfuryl alcohol to 2,5-bis(hydroxymethyl)furan (BHMF), respectively, at temperatures of lower than 100 °C and high H2 pressures. Owing to unique pore structure and small-sized copper nanoparticles entangled with alumina, meso-CuA turned out to be superior to other supported Cu catalysts in the hydrogenation of HMF to BHMF. Moreover, meso-CuA showed highly durable performance at the BHMF yield of higher than 90% at 100 °C, 50 bar H2, and weight hourly space velocity of 0.2 h−1 over time-on-stream of 100 h. The stability was also confirmed with the HMF feed containing 1 wt% of water that proved to have more considerable effect than other possible impurities. Centering around a catalytic reactor packed with meso-CuA, a process scheme from HMF feed to pure BHMF solid was developed at a production scale of 100 kg per day. The present results can contribute to designing commercial process of BHMF production from HMF and further, real biomass.

Cr-Cu/ZSM-5 zeolite catalysts were prepared by ion exchanged method and were characterized by XRD, SEM-EDS. The catalysts were applied to catalyze the transformation of corn-cob derived glucose into 5-hydroxymethyl furfural (HMF) under suitable reaction conditions. The effect of reaction conditions such as: catalyst dosage, temperature and reaction time on the yield of HMF product was investigated. The highest HMF yield of 32.6% was obtained when transformation carried out at suitable reaction conditions.

Highly stereo- and enantioselective synthesis of (E)-δ-hydroxymethyl-anti-homoallylic alcohols is reported. Under the developed conditions, reactions between aldehydes and chiral nonracemic α-borylmethyl-(E)-crotylboronate upon oxidative workup gave δ-hydroxymethyl-anti-homoallylic alcohols with high E-selectivities and enantioselectivities.

A novel and green route for the synthesis of cyclopentane-1,3-diamine (CPDA) from hemicellulosic feed-stock is established in this work. Through many explorations and optimizations, the single successful multi-step synthesis was found to comprise: (1) the Piancatelli rearrangement of furfuryl alcohol to 4-hydroxycyclopent-2-enone (4-HCP), (2) a highly improved isomerization of 4-HCP into cyclopentane-1,3-dione (CPDO) using the Ru Shvo catalyst, (3) conversion of CPDO into cyclopentane-1,3-dioxime (CPDX), and (4) a mild oxime hydrogenation of CPDX over Rh/C to afford the desired CPDA. In addition, diastereomerically pure cis- and trans-isomers of CPDA were reacted with (A) bio-based lactones, and (B) 5-(hydroxymethyl)furfural (HMF) to synthesize novel bifunctional diol monomers with internal amide and imine groups, respectively. Monomer 5, derived using gamma-valerolactone (GVL), was successfully applied in the synthesis of polyurethanes.

Zinc methyl 3-hydroxymethyl-pyropheophorbides-[Formula: see text] bearing an acetyl or nitro group at the 20-position were prepared by chemically modifying natural chlorophyll-[Formula: see text]. The synthetic zinc 20-substituted bacteriochlorophyll-[Formula: see text] analogs self-aggregated in an aqueous Triton X-100 micelle solution to give red-shifted and broadened electronic absorption bands, similarly as in one of the photosynthetic light-harvesting antennas, chlorosomes. Although the sterically bulky 20-substituents of the semisynthetic zinc 31-hydroxy-131-oxo-chlorins partially disturbed the chlorosomal self-aggregates which would be produced by the [Formula: see text]–[Formula: see text] stacking of the chlorin chromophores, their electron-withdrawing abilities should enhance the specific, intermolecular interaction of Zn[Formula: see text]O32–H[Formula: see text]O=C-13 which was essential for the chlorosomal self-aggregation. Such self-assemblies using these model pigments would provide a new clue for constructing of artificial photosynthetic systems.

Two isostructural tetranuclear lanthanide clusters named [Ln4(L)4(CH3O)4]·CH3OH (Ln = Gd(III) for 1, Dy(III) for 2, H2L = N′-(2-hydroxy-3-methoxybenzylidene)-6-(hydroxymethyl) picolinohydrazide) were successfully isolated by using a polydentate Schiff based ligand and Ln(III) nitrate salts. The structures of 1 and 2 were characterized by X-ray structural analyses, they are held by four double deprotonated ligands L2−. In them all the lanthanide ions are eight-coordinated and distributed over four vertices of a parallelogram, presenting a Ln4 cluster with a strict [2 × 2] square grid pattern. The details of magnetic analysis show that 1 displays weak anti-ferromagnetic exchange between neighboring Gd(III) ions through carboxylate oxygen and methanol oxygen ligand atoms. Furthermore, 1 exhibits significant magnetocaloric effect with the maximum entropy change –ΔSm value of 28.5 J/(kg·K) for ΔH = 7.0 T at 2.0 K. For compound 2, remarkable slow magnetic relaxation behaviors are observed in the presence of zero magnetic field with τ0 = 1.02 × 10−6 s and energy barrier ΔE/kB = 43.24 K.

Modification of the quinolizine backbone of the alkaloid lupinine was carried out by introducing substituted 1,2,3-triazole. When NaN3 acts upon the product of the reaction of lupinine with methanesulfonyl chloride, lupinyl azide is formed which in the reaction with terminal alkynes in the presence of aqueous CuSO4 and sodium ascorbate forms the corresponding (1S,9aR)-1-[(1,2,3-triazol-1-yl)-methyl]octahydro-1H-quinolizines with various substituents at the C-4 position of the triazole ring. The structures of lupinine methanesulfonate and 1-[(1,2,3-triazol-1-yl)methyl]octahydroquinolizines were confirmed by X-ray structural analysis. 1-[(1,2,3-Triazol-1-yl)methyl]octahydroquinolizines containing a hydroxymethyl or 2-hydroxypropan-2-yl substituent at the C-4 position of the triazole ring exhibit pronounced analgesic activity.

Five α-D-ribofuranose analogues (2, 3, 4, 5 and 6) were synthesized in good yields from 3-O-benzyl-4-C-(hydroxymethyl)-1, 2-O-isopropylidene-α-D-ribofuranose (1). The synthesized compounds were then subjected to analgesic, anti-inflammatory, antimicrobial and antioxidant assays. Compound 3 demonstrated 79.74% (P

Two new tetranuclear zinc(II) complexes, [Zn 4 (L 1 ) 2 ( μ 2 - η 1 : η 1 -CH 3 COO) 4 ( μ 1,1 -N 3 ) 2 ] ( 1 ) and [Zn 4 (L 2 ) 4 (CH 3 CH 2 OH)(H 2 O)] ( 2 ), where L 1 and L 2 are the deprotonated forms of 4-fluoro-2-((pyridin-2-ylmethylimino)methyl)phenol (HL 1 ) and 4-fluoro-2-((2-(hydroxymethyl)phenylimino)methyl)phenol (H 2 L 2 ), have been synthesized and characterized by elemental analysis, IR and UV-vis spectroscopy, and single crystal X-ray diffraction. X-ray crystal structural study indicated that the distances between the adjacent Zn atoms are 3.160(1)–3.353(1) A in 1 and 3.005(1)–3.168(1) A in 2 . All zinc atoms in 1 are pentacoordinated in trigonal bipyramidal geometry, and those in 2 are in square pyramidal and octahedral geometry. The complexes and the Schiff bases were assayed for antibacterial activities against three Gram-positive bacterial strains ( B. subtilis , S. aureus , and St. faecalis ) and three Gram-negative bacterial strains ( E. coli , P. aeruginosa , and E. cloacae ) by MTT method.

Designing hybrid molecules with dual functions is one approach to improve the therapeutic efficacy of combination treatment. We have previously conjugated phthalazine and bis(hydroxymethyl)pyrrole pharmacophores to form hybrids bearing antiangiogenesis and DNA interstrand cross-linking activities. To improve the bioavailability, we adopted a benzology approach to design and synthesize a new series of 1,2-bis(hydroxymethyl)benzo[g]pyrrolo[2,1-a]phthalazines. These new hybrids retained the dual functions and could be formulated into vehicles for intravenous and oral administration. Among them, we demonstrated that compound 19a with dimethylamine at the C6 position markedly suppressed the tumor growth of human small cell lung cancer cell line H526, squamous lung cancer cell line H520, and renal cancer cell line 786-O in nude mice, implying that compound 19a is a broad-spectrum anticancer agent. Our results implicated that the conjugation of antiangiogenic and DNA cross-linking is likely to be a helpful approach to improving the efficacy of combination therapy.

N-Hydroxysuccinimide esters of small molecules are widely used to modify biomolecules such as antibodies or proteins. Primary amine groups preferably react with the ester to form covalent amide bonds. Currently, protocols strongly recommend replacing the buffer reagent tris(hydroxymethyl)aminomethane, and it has even been proposed as a stop reagent. Here, we show that TRIS indeed does not interfere with biotinylation of biomolecules with NHS chemistry.

Pyrano[3,2-b]pyrans are an important class of heterocyclic compound containing fused 4H-pyrans rings that are a structural constituent of many natural, non-natural, drug candidates, synthetic compo...

In the present study, the synthesis and catalytic application of a novel thioglycolic acid doped on Fe3O4 nanomagnetic particles coated with tris(hydroxymethyl)aminomethane (THAM) and 1,2-dichloroethane are described. The morphology, structure, and physicochemical properties have elucidated by several analytical methods like FT-IR, TEM, VSM, XRD, TGA, and FE-SEM. This nanocatalyst has successfully applied as a heterogeneous acid catalyst in the synthesis of diversely substituted biologically important xanthene and 3-aminoisoxazole derivatives. This catalyst eliminates our need for long-time reaction and hard catalyst separation from product, and it can be easily recovered with an external magnet for eight consecutive times without a significant decrease in its catalytic properties.

A novel Schiff base ligand, 4-fluoro-N-((3-hydroxy-5-(hydroxymethyl)-2-methylpyridin-4-yl)methylene)benzohydrazide (PLFBH) was synthesized by condensationof pyridoxal and 4-fluorobenzohydrazide. Its complexes with Ni(II), Cu(II), and Zn(II) metal ionswere prepared and characterized by spectroscopic IR, 1H-NMR, UV, LC-MS, ESR, and powder XRD studies and by elemental analysis and thermal analysis, molar conductance, and magnetic susceptibility measurements. The results indicate the geometry of the complexes to be hexa coordinate distorted octahedral. Based on the electronic absorption and fluorescence emission spectra and viscosity studies, an intercalative mode of binding of the complexes with CT-DNA was suggested, which was also supported by DNA docking studies. The docking studies of metal complexes with DNA were carried out using Autodock 4.2. The in vitro anticancer assay for the Cu(II)-PLFBH complex was performed to assess the ability of the complex to inhibit human cell proliferation on HeLa human cervical carcinoma cells, MCF-7 human breast carcinoma cells, and A549 human lung carcinoma cells. The Cu(II)-PLFBH complex exhibited moderate to good inhibitory effect on the cancer cell lines studied. The complexes showed good cleavageability toward plasmid pBR322 DNA. The metal complexes were found to show good antibacterial activity against gram positive bacteria, Staphylococcus aureus and Bacillus cereus and gram negative bacteria Escherichia coli and Pseudomonas aeruginosa cultures,while the ligand showed marginal activity.Supplemental data for this article is available online at https://doi.org/10.1080/15257770.2021.1961271 .

The reaction of phenyl isocyanate with pyridoxal is carried out with the participation of hydroxymethyl and phenolic groups with the formation of dicarbamate derivatives. The reactions of pyridoxal azomethines with phenyl isocyanate, depending on the structure and the ratio of the starting reagents, lead to the formation of mono-, di- or tricarbamate derivatives. The product of addition of azomethine pyridoxal to phenyl isocyanate with the participation of a hydroxymethyl group was obtained.

Microwave assisted homogeneous heating, selectivity in radical formation, and the faster polymerization facilitate the synthesis, structures, properties, and the higher branching associated stability of multifunctional multipolymers. Thus, the optimum gum tragacanth (GMTR)-grafted pentapolymer hydrogel/ HG2 was synthesized from three monomers, i.e., cis-butenedioic acid (cBDA), N-hydroxymethylacryalamide (NHMAm), and 2-(methacryloyloxy)ethanol (MAOE), and in situ generated 2-(3-((hydroxymethyl)amino)-3-oxopropoxy)ethyl-2-methylbutanoate (CM1) and 2-hydroxyethyl 3-(N-(hydroxymethyl)-2-methylbutanamido)-2-methylpropanoate (CM2) comonomers through microwave assisted facile polymerization in aqueous medium. Here, twenty-one GMTR-grafted-[cBDA-co-CM1-co-NHMAm-co-CM2-co-MAOE/ HG1] hydrogels were prepared by using variable amounts of synthesis parameters, of which the optimum HG2 was chosen for the scale-up repetitive As(III)-exclusion. RSM was used to measure the optimum power-temperature-time of microwave irradiation. The structures of HG1, HG2, and As(III)-adsorbed HG2/ As(III)-HG2, in situ anchored comonomers, GMTR-grafting, reusability, thermostability, and surface phenomena were comprehended by XPS, NMR, UV–vis, FTIR, TG, XRD, DLS, and SEM analyses; pHPZC; network parameters; and thermodynamic variables. The geometries, electronic structures, and variable coordinations of As(III) with HG2 were investigated through DFT studies of HG2 and As(OH)3-HG2. The highest exclusion efficiency of 25 mg HG2 within 5–100 mg L−1 As(III) and at 298 K was 192.91 mg g−1, which was significantly higher than that of HG1.

An undescribed tricyclic spiroketal compound clathriketal was purified from the solvent extract of the Microcionidae sponge Clathria prolifera, and was characterised as 7-(hydroxymethyl)-13-methoxy-3,11-dimethyl-4-oxo-octahydrospiro[chromene-9,13-pyran]-11-yl propionate by spectroscopic experiments. Clathriketal exhibited significant anti-hyperglycemic property by attenuating serine protease dipeptidyl peptidase-IV (IC50 0.37 mM), and its activity was comparable with the standard diprotin A (IC50 0.31 mM). The spiroketal also exhibited significant inhibitory potentials against carbolytic enzymes α-glucosidase (IC50 0.43 mM) and α-amylase (IC50 0.41 mM). Superior antioxidant properties of clathriketal against the oxidants, 2, 2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid and 2, 2-diphenyl-1-picrylhydrazyl (IC50 ∼1.2 mM) also reinforced its promising anti-hyperglycemic activity. Considerably greater topological surface area (91.29) coupled with lesser steric parameters of clathriketal, as elucidated from the structure-activity relationship analyses could further ascribe the improved ligand-receptor interactions resulting in its prospective anti-hyperglycemic activity. Molecular docking analysis of clathriketal with dipeptidyl peptidase-IV recorded lesser binding energy (–9.63 kcal/mol), which further corroborated its prospective antihyperglycemic activity.

Preservation of juices is essential to obtain microbial safe products. There are various established methods as pasteurization. Heretofore, only the kinetic figures of microbial inactivation were considered but not those of reaction impairing the chemical quality. For a gentler processing, knowledge of the kinetics of relevant chemical conversion reactions is necessary. 5-(Hydroxymethyl)-furfural (HMF) formation and the color change of juices are important attributes. The non-isothermal Rhim method was used to determine the activation energy and pre-exponential factor for HMF formation in different juices and an isothermal method for the reaction order. Values for the activation energy from 133 to 303 kJ/mol were obtained with a zeroth reaction order. A correlation between HMF and the color change could be found. Based on the kinetic figures, lines with equal effects for the chemical changes and for the lethal effect on microorganisms were calculated. Time-temperature settings for the gentlest treatment could be found.

Stress testing of active pharmaceutical ingredients (API) is an important tool used to gauge chemical stability and identify potential degradation products. While different flavors of API stress testing systems have been used in experimental investigations for decades, the detailed kinetics of such systems as well as the chemical composition of prominent reactive species, specifically reactive oxygen species, are unknown. As a first step toward understanding and modeling API oxidation in stress testing, we investigated a typical radical "soup" solution an API is subject to during stress testing. Here we applied ab initio electronic structure calculations to automatically generate and refine a detailed chemical kinetics model, taking a fresh look at API oxidation. We generated a detailed kinetic model for a representative azobis(isobutyronitrile) (AIBN)/H2O/CH3OH stress-testing system with a varied cosolvent ratio (50%/50%-99.5%/0.5% vol water/methanol) for 5.0 mM AIBN and representative pH values of 4-10 at 40 °C that was stirred and open to the atmosphere. At acidic conditions, hydroxymethyl alkoxyl is the dominant alkoxyl radical, and at basic conditions, for most studied initial methanol concentrations, cyanoisopropyl alkoxyl becomes the dominant alkoxyl radical, albeit at an overall lower concentration. At acidic conditions, the levels of cyanoisopropyl peroxyl, hydroxymethyl peroxyl, and hydroperoxyl radicals are relatively high and comparable, while, at both neutral and basic pH conditions, superoxide becomes the prominent radical in the system. The present work reveals the prominent species in a common model API stress testing system at various cosolvent and pH conditions, sets the stage for an in-depth quantitative API kinetic study, and demonstrates the usage of novel software tools for automated chemical kinetic model generation and ab initio refinement.

A method for seeded growth of particles with uniform, smooth spherical shape, and narrow size distributions is presented. By using formaldehyde (HCHO) as a reductant and without any stabilizer in an aqueous solution, gold nanoparticles with sizes up to 220 nm were prepared at room temperature. The gold nanoparticles (diameter in the range of 1–3 nm) for the first seeds are synthesized by the reduction of tetrachloroauric acid trihydrate (HAuCl4) with tetrakis (hydroxymethyl) phosphonium chloride THPC (P(CH2OH)4Cl). These seeds are dispersed in the gold plating solution at pH 9.0 in the presence of HCHO. Through multi-step seeding growth, their sizes are precisely controlled just by adjusting the ratio of gold precursor to seeds. The obtained gold nanospheres are characterized by using transmission electron microscopy, a Zetasizer Nano, and UV–VIS absorption spectroscopy. This approach has excellent reproducibility and can significantly improve the monodispersity of nanospheres.

Two proton-conductive and luminescent organic-inorganic hybrid materials, {[Cu(II)(bhmbpy)(H2O)(Cl)0.5(CH3CN)]2[PW(VI)10W(V)2O39]}·4H2O(1) and {H2[Cu(I)(bhmbpy)2(Cl)Cu(I)(bhmbpy)2][PW12O40]}·7H2O (2) (where bhmbpy is bis(hydroxymethyl)-2,2′-bipyridine), were synthesized at room temperature. The two products were characterized by infrared spectroscopy, X-ray single-crystal diffraction, X-ray powder diffraction, elemental and thermogravimetric analyses. The proton conductivities and luminescence of 1 and 2 were studied by using alternating-current impedance spectroscopy and luminescence spectroscopy, respectively. X-ray diffraction analysis revealed that 1 includes a decorated polyanion chain {[Cu(II)(bhmbpy)(H2O)(Cl)0.5(CH3CN)]2[PW(VI)10W(V)2O39]}n and forms a three-dimensional network structure depending on short Cl…Cl contacts and hydrogen-bonding interactions. X-ray diffraction analysis revealed that 2 includes a butterfly-like bi-nuclear copper cluster unit with a Cl-bridge, [Cu(I)(bhmbpy)2(Cl)Cu(I)(bhmbpy)2]+, and forms a three-dimensional network structure depending on hydrogen-bonding interactions. [PW12O40]3– anions fill in the network based on hydrogen-bonding and electrostatic interactions. In them, the bhmbpy acts as a bidentate nitrogen donor ligand in the chelating fashion to coordinate with the Cu(II) center in 1 and the Cu(I) center in 2. The bhmbpy in 2 successfully constrains the Cu(I) within a rigid environment in a tetragonal-pyramidal geometry. The two compounds exhibit good proton conductivity (10−4 S·cm−1) at 100 °C in the relative humidity range 35–98%. Their luminescence behaviors in the solid state at room temperature have also been investigated. Upon excitation at 384 nm, 1 exhibits three emission peaks centered at 439, 507 and 566 nm. When excited at 364 nm, 2 displays three emission peaks centered at 443, 501 and 553 nm.

An extract from the knotwood of Abies sibirica (Siberian fir) was studied by HPLC, NMR spectroscopy, and mass spectrometry with the goal to identify new sources of phytoestrogens, which are promising medicinal agents, and to obtain new representatives of natural compounds of the indicated group. The following compounds were found in the extract and identified: 2-(4-hydroxy-3-methoxyphenyl)-3-hydroxymethyl-4-[1-hydroxy-1-(4-hydroxy-3-methoxy-phenyl)methyl]tetrahydrofuran (1), 5′-(7-hydroxymatairesinyl)-5″-(7‴-hydroxymatairesinol) (2), 2,3-bis(4-hydroxy-3-methoxybenzyl)butane-1,4-diol (3, (−)-secoisolariciresinol), and 3-(4-hydroxy-3-methoxybenzyl)-5-(4-hydroxy-3-methoxyphenyl)-4-(hydroxymethyl)dihydro-furan-2(3H)-one (4). Compound 2 was previously unknown.

6-Hydroxymethyl indolizidin-2-one amino acids were synthesized in 10 steps from l-serine by intramolecular ring opening of a symmetrical epoxide and lactam formation. X-ray analyses indicated the bicycles replicated ideal peptide type II' β-turn central dihedral angle geometry. Inside a prostaglandin-F2α receptor modulator, the 6-hydroxymethyl analogue retained inhibitory activity on myometrial contractility.

A series of novel zinc-polyurethane copolymers, which contained zinc cations in the form of polymeric salt and can be exchanged with the sodium ions in sea water, was prepared. As the ion exchange reaction proceeded, the zinc-polyurethane copolymers became soluble and leached out by the flow of sea water. The self-polishing rates of marine antifouling coatings formulated with the polymers proved to be easily controlled by the amount of 2,2-bis(hydroxymethyl) propionic acid. Marine field test revealed that zinc-polyurethane antifouling coatings had excellent efficiency in preventing marine biofouling for more than 12 months. These results proved that the zinc-polyurethane copolymers were a good candidate for the preparation of long-efficiency and controllable marine antifouling coatings.

Polymer chain-extenders with one (AE, i.e., aminoethanol), two (APD, i.e., 2-amino-1,3-propanediol), and three (tris, i.e., 2-amino-2-(hydroxymethyl)-1,3-propanediol) pendant ethanol groups were us...

Objective: Structural elucidation of bioactive compounds from marine Sponge Suberites Carnosus (Johnston) by using Thin Layer Chromatography (TLC), Gas Chromatography-Mass Spectrometry (GC-MS), Fourier Transform Infrared Spectrometer (FTIR) techniques with respect to its pharmacological and biomedical properties. Methods: The sponge Suberites carnosus (Johnston) was collected during low tides from West Coast of Mumbai. Crude extract was obtained by taking 10 gram of sponge sample in10 ml of methanol. The preparative TLC (Thin Layer Chromatography) was performed by using Toluene: Ethyl acetate: Diethylamine (7:2:1) (v/v). The isolated compounds were subjected to GC-MS and FTIR analysis. Results: From the GC-MS and FTIR analysis, total ten compounds were identified. The GC-MS spectra correlate to the mass spectra. The structures of those compounds are 6-Fluoro 2-trifluromethylbenzoic acid,2,3-dichlorophenyl ester, Eicosane 3-cyclohexyl, Phosphine imide, P,P,P,-tris (p-chlorophenyl)-N-phenyl-, Dimethylhyl hexavinyl octasilsesquioxane, Hexanoicacid, hexadecyl ester, Hexadecanoic acid,2-hydroxy1-(hydroxymethyl)ethyl ester, 9, 19-Cyclolanostan-3-ol, acetate, (3β), Tetracosane, 3-ethyl-, 11, 14-Eicosadienoic acid, methyl ester, Triacontane, 11,20-didecyl-respectively. Conclusion: The nature and biological properties of the said compounds were determined and it was found that some of them act as a skin irritant. Some of them have fatty, metabolite, and irritant property, whereas some are act as masking and perfuming agents. Some compounds are highly toxic property, whereas others have an effect on health and environmental hazard. Some are highly corrosive in nature, whereas others are Cholesterol and chemotaxonomic significance.