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Converting carbon dioxide into formic acid with formate dehydrogenase (FDH) as a catalyst is a gentle and eco‐friendly process that not only conserves energy and reduces emissions but transforms waste into valuable resource. Enzyme immobilization is a common strategy for improving the stability and recyclability of enzyme, however, the procedures are usually complicated that include surface modification and binding reactions in order to form reliable linkages. Co‐deposition of polydopamine (PDA) with polyethyleneimine (PEI) is a popular surface modification approach in versatile fields, but their co‐deposition with enzymes is rarely reported. Herein, one‐pot immobilization of FDH on SiO2 nanoparticles based on catechol chemistry was attempted for the first time with or without PEI, and the resultant immobilized enzymes, FDH/PDA/PEI‐SiO2 and FDH/PDA‐SiO2, were characterized, and the effects of the composition and deposition conditions on the catalytic performance were investigated. FDH/PDA‐SiO2 exhibited a higher apparent specific activity than FDH/PDA/PEI‐SiO2, which was separately 0.167 and 0.136 mM/h/mg. The activity recovery rate was 464% and 378% of that of free enzyme. After 5 cycles, their relative activity was 82.3% and 87.4%. This research is significant in presenting a simple and high‐efficient one‐pot immobilization method that can be extended to other kinds of enzymes. [ABSTRACT FROM AUTHOR]

Trimerizing furoxans are ideal molecular skeletons for the construction of high energetic substances due to their compact structures and high enthalpy of formations. To explore and compare the thermal behaviors of energetic materials with tandem trimerizing furoxan molecular skeleton, we reported the first systematic research on the thermochemical behaviors and decomposition mechanism of 3,4‐bis(3‐fluorodinitromethylfuroxan‐4‐yl)furoxan (BFTF), 3,4‐bis(3‐cyanofurazan)furazan oxide (BCTFO) and benzotrifuroxan (BTF). According to the research results of the DSC‐TG experiments, both the substituted furoxan based energetic compounds (BCTFO and BFTF) exhibited low melting points and complicated thermal decomposition behaviors around 240 °C, while the melting point of unsubstituted furoxan (BTF) was much higher. Their detailed decomposition mechanisms were proposed based on the experimental results through tandem techniques including in‐situ FTIR spectroscopy method and DSC‐TG‐FTIR‐MS quadruple technology, which indicated that the cleavage of substituent would trigger the decompositions of BFTF and the decomposition of trimerizing furoxan skeletons almost synchronous occurrence with substituents in BCTFO. The self‐oxidation‐reduction of the linear and annular trimerizing furoxans lead to similar decomposition fragmented small molecule products. [ABSTRACT FROM AUTHOR]

Organoaluminum compounds have been employed as catalysts in many reactions. However, due to their high reactivity of the Al−C bond towards water or air, the accurate analysis and detection of organoaluminum compounds are still challenging. Here we demonstrate the possibility of rapidly and precisely detecting the purity and impurities of triethylaluminium (TEAL). An indirect GC‐MS method via alcoholysis reaction using a designed alcoholysis reactor was adopted to detect and separate the main components and impurities of the synthesized TEAL. Previously, the nuclear magnetic resonance (NMR) and the inductively coupled plasma‐mass spectrometer (ICP‐MS) methods were also selected to detect the main compounds in the synthesized TEAL. The impurities in TEAL was identified as n‐butyl aluminum, and the purity of synthesized TEAL is 97.47 % with high accuracy (ca. 99 %). This work suggests a new strategy to detect the purity and impurities of some kind of hazardous compounds. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a common degenerative disease of the central nervous system among the elderly. Istradefylline, an FDA‐approved adenosine A2A receptor antagonist (anti‐PD drug), has good efficacy. However, it has been reported that the double bond of istradefylline is easily converted into cis‐configuration when exposed to an indoor environment or direct light in a dilute solution. In order to find more stable adenosine A2A receptor antagonists with similar pharmacological efficacy to istradefylline, the compounds series I‐1 (12 compounds) was designed by maintaining the xanthine skeleton of istradefylline unchanged and replacing the trans‐double bond with thiazole or benzothiazole and other biologically active heterocyclic compounds. These compounds were synthesized via multi‐step experiment and successfully confirmed through different characterization techniques for their ability to inhibit cAMP formation in A2AAR overexpressing cells. The thiazole derivative of istradefylline (Compound I‐1‐11, I‐1‐12) exhibited significant activity (IC50 = 16.74 ± 4.11 μM, 10.36 ± 3.09 μM), as compared to istradefylline (IC50 = 5.05 ± 1.32 μM). In addition, the molecular docking of benzothiazole derivatives I‐1‐11 and thiazole derivatives I‐1‐12 with higher inhibition rate were carried out and compared with istradefylline. The molecular docking results showed that I‐1‐11 and I‐1‐12 anchored in the same site as that of XAC (3REY) with predicted affinity binding energy −6.63 kcal/mol and − 6.75 kcal/mol, respectively. Validation through dynamics simulation also showed stable interactions, with fluctuations <3 Å and MM/GBSA energy <−20 kcal/mol. Hence, this study could provide a basis for the rational design of adenosine A2A receptor antagonists with better potency. [ABSTRACT FROM AUTHOR]

Aptamer‐based hydrogels have drawn great attention due to their biocompatibility, mechanical properties, responsiveness, and stability. Aptamers are utilized to obtain specific molecular recognition. Aptamers are short single‐stranded DNA (ssDNA) or RNA molecules selected through systematic evolution of ligands by exponential enrichment (SELEX) process, to bind to a specific target with high affinity and specificity. Aptamer functionalized hydrogels have become popular in a wide range of promising applications with the advantages of a vast target distribution, good stability, easy modification, and low cost. In this review, the recent progress on aptamer functionalized hydrogels including their design, fabrication, and bio‐sensing applications have been summarized. The prospects and challenges have also been discussed. [ABSTRACT FROM AUTHOR]

The detection and separation of impurities are crucial for the quality control of triethylboron. While the purity of triethylboron is the key factor for ballistic performance, impact accuracy, and storage safety. This work will explore a modified gas chromatography‐mass spectrometer method to detect and separate the impurities in synthesized triethylboron. They are identified as CH3CH2OCH2CH3, (CH3CH2)3B, (CH3CH2O)3B, CH3CH2CH2CH2B(CH3CH2)2 and (CH3CH2)3O3B3. Further, optimized GC conditions are demonstrated to quantify the synthesized triethylboron accurately and determine its purity. The purity of triethylboron is 96.39 % via a normalization method with high accuracy (RSD=0.05 %). The optimized GC conditions were as follows: a hydrogen flame ionization detector, nitrogen as carrier gas whose pathway was installed with a water trap and an oxygen trap, an HP‐5 capillary column (30 m×0.32 mm×0.25 μm) with the column temperature of 60 °C, an inlet temperature of 120 °C, the detector temperature of 150 °C, and an injection volume of 0.6 μL. This work demonstrates a simple and precise method to analyze the synthesized triethylboron and its impurities. [ABSTRACT FROM AUTHOR]

Photonic glasses with infrared gaps can be used as surface coating materials to effectively change the infrared radiation characteristics of substrate. In this research, a photonic glass with an infrared broad gap could be prepared easily in thermostatic water bath by a simple and fast baking protocol. The photonic glass prepared had a broad gap from 4.25 to 4.57 μm, centering at 4.45 μm, which was slightly different from the result of numerical simulation due to the existence of the internal disordered structure. The infrared transmission diagram showed that the infrared transmittance of a substrate covered by the photonic glass can be reduced from 80 % to 25 % at infrared atmosphere window of 3∼5 μm, which proved the ability of the material to regulate and control the infrared electromagnetic wave. In addition, the material can significantly restrain the infrared radiation of the substrate at 60 °C, which was expected to achieve stealth under the infrared detection. [ABSTRACT FROM AUTHOR]

Istradefylline is a selective adenosine antagonist for A2a receptor, and it is used to treat Parkinson's syndrome and improve dyskinesia in the early stage of Parkinson's disease. Istradefylline aqueous solution were preserved in darkness and light respectively, and it was found that Istradefylline aqueous solution were extremely unstable in light. An impurity of Istradefylline was identified by HPLC and further collected by preparative HPLC. The impurity was characterized by NMR and MS and identified as Z‐Istradefylline, a photo degradation product of Istradefylline. The founding of degradation phenomenon makes the research on the stability of Istradefylline aqueous solution absolutely necessary for the quality control of the drug. [ABSTRACT FROM AUTHOR]

The application of fluorescent method to metal ions detection features high sensitivity, simple operation and real‐time monitoring. A 2,7‐dihydroxynaphthalene‐functionalized dimethyl glycoluril (called clip 1) was synthesized, using a relatively simple method. And it is fully characterized by 1H NMR, 13C NMR, HR‐MS and single crystal X‐ray diffraction. The recognition properties of molecular clip 1 were analyzed systematically toward several metal ions using fluorescence spectroscopy, and it was found that molecular clip 1 is selective and sensitive to Fe3+. At the same time, the clip 1 shows good anti‐interference ability when other metal ions existed. The limit detection of Fe3+ is 3×10−7M. The fluorescence of clip 1 was quenched apparently by Fe3+, which was speculated to be caused by ligand–metal charge transfer mechanism (LMCT). As a new fluorescence probe for Fe3+ ion, it may expanded the application of glycoluril molecular clips. [ABSTRACT FROM AUTHOR]

Self‐monitoring of blood glucose is not only an effective method to treat diabetes, but also a painful invasive process to patients. To develop a noninvasive technique, we evaluated the clinical performance of a polymerized crystalline colloidal array (PCCA) sensor for glucose monitoring in urine. A two‐dimensional crystalline colloidal array (CCA) was assembled using polystyrene particles and further embedded into 3‐acrylamidophenylboronic acid functionalized hydrogel. 101 urine samples were tested, and the glucose concentrations was calculated by the particle spacing of PCCA. All the urine samples were also analyzed by automated urine analyzers. Pearson correlation and linear regression analyses showed a linear relationship between the PCCA results with a range of 0.4‐53.3 mmol L−1 and the Cobas® 8000 references (r=0.914; [PCCA]=0.9281 [HK] + 2.0585 mmol L−1). Cohen's kappa (κ) statistic with 0.65 (sig < 0.05) showed the PCCA results had moderate agreement with references. Also, Bland‐Altman plot showed that AX‐4030 sensor's systematic error was higher than PCCA sensor (mean=7.4813 > 0.5271 mmol L−1). The PCCA urine glucose biosensor has the advantages of fast fabrication, low cost, easy operation and high sensitivity, which provides a promising technique for noninvasive point‐of‐care glucose monitoring. [ABSTRACT FROM AUTHOR]

A novel synthetic method of the 1, 3, 5‐trinitro‐2, 2‐bis(trifluoromethyl)‐1,3,5‐triazinane (2) has been successfully developed. In addition to IR, 1H 13C NMR and elemental analysis, compound 2 was characterized by 15N NMR and X‐ray single crystal diffraction. Due to the introduction of trifluoromethyl, the density of compound 2 is up to 2.04 g⋅cm−3 at 298 K, which is consistent with its crystal density (2.059 g⋅cm−3, 296(2) K). Compound 2 exhibits excellent detonation pressures and velocities (P, 45.6 GPa; vD, 9564 m⋅s−1), as good as exceptional impact and friction sensitivities(IS, 22.5 J; FS, >360 J). Some of these values are better than the current benchmark explosives, such as 1, 3, 5‐trinitrodihydro‐1, 3, 5‐triazine (RDX) and cyclo‐1, 3, 5, 7‐tetramethylenene‐2, 4, 6, 8‐tetranitramine (HMX).It is a potential high energy density material. [ABSTRACT FROM AUTHOR]

A new glycoluril derivative‐1H, 4H, 5H, 8H‐2, 3a, 4a, 6, 7a, 8a‐hexaazacyclopenta[def]fluorene‐4, 8‐dione, hexahydro‐2, 6‐bis(phenylmethyl) (3) is strategically designed and synthesized through the reaction between glycoluril, formaldehyde and benzylamine with the optimized molar ratio of 1:6:2. Compound 3 is fully characterized by 1H NMR, 13C NMR, IR, MS and X‐ray single crystal diffraction. Reduction of compound 3 delivers a potential precursor‐imidazo[4, 5‐d]imidazole, octahydro‐hexahydro‐2, 6‐bis(phenylmethyl) (4) for the synthesis of novel nitramine explosives (i.e. bicyclo‐HMX and bi‐RDX). The nitration and hydrolysis of compound 4 are investigated in detail and three ring‐opened molecules N, 2, 4‐trinitro‐benzenemethanamine (8a), N, 2‐dinitro‐benzenemethanamine (8b) and N‐methylene‐benzenemethanamine (9) are obtained. The synthesis, X‐ray crystal structure, hydrolysis, nitrolysis of two potential precursors for the preparation of nitramine explosives (bicycle‐HMX and bi‐RDX) are reported. [ABSTRACT FROM AUTHOR]

Raman spectroscopy as a rapid and sensitive qualitative detection method has been applied in many fields; however, it is rarely used for the quantitative purpose due to poor reproducibility of peak area. Here, 2,4,6‐trinitrotoluene (TNT) and its two byproducts, 2,4‐dinitrotoluence (DNT) and 2,6‐DNT, were firstly qualitatively analyzed by Raman spectroscopy and the characteristic parameters were extracted. Then, in the range of 2 %–9 % and 10 %–90 %, the standard curves were established between the area ratio of the characteristic peaks and the content of 2,4‐DNT or 2,6‐DNT using silver nanoflowers as the enhancing substrate. The fitting correlation for TNT/2,4‐DNT or TNT/2,6‐DNT system is around 0.99. The peak area ratio of the components exhibits much better dada reproducibility than peak area, and the relative error does not exceed 9.3 % for at least six groups of parallel experiments. [ABSTRACT FROM AUTHOR]

A novel method has been successfully developed to synthesize the guanidine salt of 1,1,2,2‐tetranitraminoethane (TNAE). By the use of IR, 1H and 13C NMR spectroscopy, the structure of the guanidine salt of TNAE was thoroughly characterized. In addition to the thermal stability investigated by TG‐DSC, the kinetic parameters of this kind of material including activation energy and the pro‐exponential factor were also calculated by Kissinger equation. The measurements of impact and friction sensitivity were carried out respectively. According to the theoretical performance calculations, the guanidine salt of TNAE exhibited the excellent detonation pressures and velocities. The solubility analysis for guanidine salt of TNAE by HPLC was performed at different temperatures, revealing the solubility increased with the increasing of temperature. And its solubility was proved to be the best in water among all the experimented solvents, ethyl acetate, dichloromethane and acetone followed up. With the great potential in practical application, the guanidine salt of TNAE is of significant value being employed as environmentally friendly gas generant, insensitive explosive and solid propellant. [ABSTRACT FROM AUTHOR]

Based on the advantages of the furazan and tetrazole ring, the nitro and N‐oxide groups were introduced into furazan‐tetrazole backbone to four kinds of novel nitrofurazan‐functionalized hydroxytetrazole energetic salts. Various method have been employed to confirm their structures, such as multinuclear NMR, FTIR spectroscopy and elemental analysis. Salt guanidinium 5‐(4‐nitro‐furazan‐3‐yl)‐tetrazole‐1‐olate (5) and salt potassium 5‐(4‐hydroxyamino‐furazan‐3‐yl)‐tetrazole‐1‐olate (6) has been further elucidated by single‐crystal X‐ray diffraction. The non‐isothermal decomposition kinetics and thermodynamics for different salts were investigated by using TG‐DSC with different heating rate. The physico‐chemical properties and detonation performance were also studied and calculated by EXPLO5 program, in which salt hydroxylammonium 5‐(4‐nitro‐furazan‐3‐yl)‐tetrazole‐1‐olate (3) have a relatively high density of 1.839 g⋅cm−3 at 296 K and good detonation properties (vD = 9228 m⋅s‐1, P = 38.0 GPa), which is superior to that of RDX. The sensitivities towards impact and friction were also determined by BAM method (BAM Fallhammer Test for IS; BAM Friction Test for FS), in which the salt 5 showed very insensitive property (IS>60 J, FS>360 N) and can be comparable to that of TATB. Furthermore, the specific impulse of salt 3 (281 s) was even better than that of ammonium perchlorate (AP) (157 s) as neat compounds. The nitro group and N‐oxide groups were introduced into furazan‐tetrazole backbone to synthesize a series of novel nitrofurazan‐functionalized hydroxytetrazole energetic salts, where salt 3 exhibited a good detonation performance and moderate sensitivity. [ABSTRACT FROM AUTHOR]

As a key precursor in the preparation of octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX), 3,7‐dinitro‐1,3,5,7‐tetraazabicyclo[3,3,1]nonane (DPT) prepared from urea by a modified one‐pot method has a bright future. On the basis of our previous work (Reaction Mechanism of One‐Pot Synthesis of Dinitro Pentamethylene Tetramine, Chinese Journal of Organic Chemistry 2010, 30 (3), 414–418.) [1], a novel intermediate 3‐nitro‐1,3,5,7‐tetraazabicyclo[3,3,1]nonane was captured and isolated, and the key reactive intermediate hexahydro‐1‐nitro‐1,3,5‐triazine was directly captured and confirmed by HPLC‐MS. Thus, a modified synthetic mechanism for DPT was elaborated, and based which DPT preparation process was optimized. [ABSTRACT FROM AUTHOR]

Abstract: We designed and synthesized a “hybrid” molecular container 1, which is structurally related to both cucurbit[n]uril (CB[n]) and pillar[n]arene type receptors. Receptor 1 was fully characterized by 1H NMR, 13C NMR, IR, MS and X‐ray single crystal diffraction. The self‐association behavior, host–guest recognition properties of 1, and the [salt] dependence of Ka were investigated in detail by 1H NMR and isothermal titration calorimetry (ITC). Optical transmittance and TEM measurements provide strong evidence that receptor 1 undergoes co‐assemble with amphiphilic guest C10 in water to form supramolecular bilayer vesicles (diameter 25.6±2.7 nm, wall thickness ≈3.5 nm) that can encapsulate the hydrophilic anticancer drug doxorubicin (DOX) and the hydrophobic dye Nile red (NR). The release of encapsulated DOX or NR from the vesicles can be triggered by hexamethonium (8 c) or spermine (10) which leads to the disruption of the supramolecular vesicles. [ABSTRACT FROM AUTHOR]

Abstract: Conjugated polymers have recently attracted a great deal of attention for applications in photodynamic therapy (PDT) because of their light‐harvesting capability, efficient energy transfer, and singlet oxygen generation properties. This review describes recent advances in PDT development, including therapeutic mechanisms of PDT in cancer treatments, light excitation methods, and especially recent advances of conjugated polyelectrolytes and conjugated polymer nanoparticles as photosensitizers. The future direction on PDT and further development of conjugated polymer photosensitizers are discussed. The aim of this review is to stimulate innovative ideas to synthesize a new generation of conjugated polymer photosensitizers and promote their translation to clinical applications of PDT. [ABSTRACT FROM AUTHOR]

Stem cell therapy is rapidly moving toward translation to clinical application. To elucidate the therapeutic effect, a robust method that allows tracking of the stem cells over an extended period of time is required. Herein, semiconducting polymer dots (Pdots) are demonstrated for their use in bright labeling and tracking of human mesenchymal stem cells (MSCs) in vitro and in vivo. The Pdots coated with a cell-penetrating peptide (R8) showed remarkable endocytic uptake efficiency that was 15 times higher than that of carboxyl Pdots and more than 200 times than that of bare Pdots. The Pdot-labeled MSCs can be traced for 15 generations in vitro and tracked over 2 weeks in vivo after subcutaneous transplantation. The labeled MSCs administered through the tail vein were preferentially accumulated in the lung; this was distinctive from the distribution of free Pdots, which were primarily distributed in the liver. Based on the properties of bright labeling, excellent tracking capability, and great biocompatibility, the Pdots will be valuable in the applications of stem cell biology and regenerative medicine. [ABSTRACT FROM AUTHOR]

The solubilities of 3,4-diaminofurazan (DAF) and 3,3′-diamino-4,4′-azoxyfurazan (DAAF) were investigated in water, dichloromethane, acetonitrile, ethyl acetate, methanol, and acetone between 293.15 K and 313.15 K. The solubility was determined by high-pressure liquid chromatography with ultraviolet detection. The solubilities of DAF and DAAF are increased with the increasing of temperature in all solvents studied. The enthalpy of solution in each solvent was calculated according to van't Hoff Equation. [ABSTRACT FROM AUTHOR]

Energetic salts readily exhibited desirable properties through appropriate combination of different cations and anions. Due to its acidity of nitramine group, 1,1,2,2‐tetranitroaminoethane (TNAE) is a good anion in energetic salts. In this paper, diaminoguanidine and hydroxylamine salts of TNAE have been synthesized and their performances were studied. Both salts of TNAE exhibit excellent detonation pressure and velocity based on theoretical performance calculation. Especially, the diaminoguanidine salt of TNAE exhibits excellent thermal stability and insensitive to impaction and friction. It will has a great potential to be applied in the field of energetic materials. TNAE is a typical energy material, which can be used as a good anion in energetic salts. Two new energetic salts of TNAE have been synthesized and fully characterized. Both salts of TNAE showed excellent explosive performance, thermal stability and insensitive to impaction. Especially, the diaminoguanidine salt of TNAE exhibits excellent insensitive to impact and friction, which has a great potential in applications. [ABSTRACT FROM AUTHOR]

The molecularly imprinted polymers (MIPs) for two structural analogs, 1,3,5-triacetyl-1,3,5-triazacyclohexane (TRAT) and 1,3,5,7-tetraacetyl-1,3,5,7-tetraazacyclooctane (TAT), have been synthesized respectively under the same conditions. The TAT-MIP showed excellent imprinting effect, whereas the TRAT-MIP did not. To understand the different imprinting effects of the MIPs prepared from these two templates, the geometric structures and energetic properties of complexes formed around TAT and TRAT were studied computationally. The results indicate that in liquid phase, for the complexes formed with TAT and its nearest neighbor molecules, the magnitude of the binding energy increases with the number of surrounding TAT, methacrylic acid, and acetonitrile (ACT), whereas for the cases of TRAT, the magnitude of the binding energy increases with the number of surrounding TRAT and trimethylolpropane trimethacrylate. The studied systems form stronger and thus more stable networks encapsulating TAT than with TRAT. ACT may also play an important role in the polymerization phase in stabilizing the shapes of the cavities that TATs reside in. We propose these as the major factors that affect the different imprinting effects of the two MIPs. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A series of high energy density compounds (HEDCs) based on N-nitrourea were designed and their theoretical performances were calculated using the Gaussian programs. The predicted values of the energy density of these compounds are in the range 1.848-1.93 g cm−3, and their calculated VODs are in the range 6700-8305 m s−1. Tetranitrodiglycoluril (TNDGU) ( 1) and tetranitrotriglycoluril (TNTGU) ( 2) were synthesized and characterized by NMR (1H, 13C) and IR spectroscopy as well as elemental analyses. The structure of the aminolysis product ( 7) of TNDGU was further confirmed by single-crystal X-ray diffraction, which indicated that the structure belongs to P21/ c space group in the monoclinic system. [ABSTRACT FROM AUTHOR]

Mono-dispersed molecularly imprinted hollow spheres (MIHSs) for hemoglobin (Hb) were prepared by employing silica nanospheres as the sacrificial templates. The obtained hollow spheres with uniform particle size of 360 nm in diameter were characterized by transmission electron microscopy. The outstanding affinities of these MIHSs to the target protein were confirmed by adsorption experiment in aqueous solution. Adsorption equilibrium was achieved within 10 min while the binding capacity ( Qmax) of Hb was 8.84 µmol g-1 at pH7.0. Furthermore, the MIHSs were successfully assembled into a closely-packed 3D colloidal array. The molecularly imprinted hollow sphere array (MIHSA) can selectively recognize Hb. As the concentration of Hb increased, the structure color of the MIHSA changed from blue to green, and turn to white finally with maximum red shift for 43 nm. The MIHSA showed promising potential for the naked-eye detection of target Hb. [ABSTRACT FROM AUTHOR]

Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) is currently one of the most widely used explosives. 1,3,5,7-Tetraacetyl-1,3,5,7-tetraazacyclooctane (TAT) is an attractive precursor for the synthesis of HMX; the nitration of this key precursor results in both high yield and purity under mild condition. TAT can be prepared either by acetylation of 2,6-diacetyl-pentamethylenetetramine (DAPT) or by the condensation of ACN and 1,3,5-trioxane. However, TAT and DAPT are polar compounds, and are difficult to analyze using reverse phase liquid chromatography. Herein, a chromatography method for the direct separation of these polar compounds was developed using hydrophilic interaction chromatography (HILIC) using a Venusil HILIC column, with ACN/water (95/5, v/v) as the mobile phase. The chromatographic analysis and identification of these polar compounds provide valuable information for the optimization of the synthetic process of TAT. [ABSTRACT FROM AUTHOR]

The novel primary explosive tetranitrodiglycoluril (TNDGU) was synthesized from glycoluril dimer. It was fully characterized by using NMR (1H, 13C), IR spectroscopy, and elemental analysis. X-ray diffraction revealed that the crystals of TNDGU belong to triclinic system with space group P $\bar 1$. The thermal behavior of TNDGU was studied using DSC methods. TNDGU exhibited good thermal stability with a decomposition temperature of 284.8 °C. TNDGU was also more resistant to hydrolysis compared to other nitrourea analogues. Additionally, density, enthalpy of formation, detonation velocity (VOD), and detonation pressure of TNDGU were predicted and it was found that TNDGU is a potential powerful explosive with a calculated density of 1.93 g cm−3, a detonation velocity of 8305 m s−1 and low sensitivity to electric discharge. [ABSTRACT FROM AUTHOR]

A polymeric catalyst was synthesized by co-polymerizing 4(5)-vinylimidazole and itaconic acid with trimethylpropanol trimethacrylate micro spheres. The catalyst obtained catalysed the transesterification process between p-nitrophenyl acetate and hexanol with maximal initial velocity(νmax) of 4.73 ± 0.47 μ M min−1 mg−1, and turnover rate ( kcat) of 8.67 min−1. Using p-nitrophenyl acetate as template, molecular imprinting process enhanced the νmax of the polymeric catalyst 3-fold. Each imprinted site can be considered as a single molecular reaction vessel, and achieved a kcat of 169 min−1 towards the conversion of p-nitrophenyl acetate in hexanol. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]