Synthesis and Characterization of 1‐Azido‐2‐Nitro‐2‐Azapropane and 1‐Nitrotetrazolato‐2‐Nitro‐2‐Azapropane

1‐Azido‐2‐nitro‐2‐azapropane ( 1 ) was synthesized in high yield from 1‐chloro‐2‐nitro‐2‐azapropane and sodium azide. 1‐Nitrotetrazolato‐2‐nitro‐2‐azapropane ( 2 ) was synthesized in high yield from 1‐chloro‐2‐nitro‐2‐azapropane and silver nitrotetrazolate. The highly energetic new compounds ( 1 and 2 ) were characterized using vibrational (IR and Raman) and multinuclear NMR spectroscopy (¹H, ¹³C, ¹⁴N), elemental analysis and low‐temperature single crystal X‐ray diffraction. 1‐Azido‐2‐nitro‐2‐azapropane ( 1 ) represents a covalently bound liquid energetic material which contains both a nitramine unit and an azide group in the molecule. 1‐Nitrotetrazolato‐2‐nitro‐2‐azapropane ( 2 ) is a covalently bound room‐temperature stable solid which contains a nitramine group and a nitrotetrazolate ring unit in the molecule. Compounds 1 and 2 are hydrolytically stable at ambient conditions. The impact sensitivity of compound 1 is very high (<1 J) whereas compound 2 is less sensitive (<6 J).     

Characterization of 4,6‐Diazido‐N‐nitro‐1,3,5‐triazine‐2‐amine

4,6‐Diazido‐N‐nitro‐1,3,5‐triazine‐2‐amine (DANT) was prepared with a 35 % yield from cyanuric chloride in a three step process. DANT was characterized by IR and NMR spectroscopy (¹H, ¹³C, ¹⁵N), single‐crystal X‐ray diffraction, and DTA. The crystal density of DANT is 1.849 g cm⁻³. The cyclization of one azido group and one nitrogen atom of the triazine group giving tetrazole was observed for DANT in a dimethyl sulfoxide solution using NMR spectroscopy. An equilibrium exists between the original DANT molecule and its cyclic form at a ratio of 7 : 3. The sensitivity of DANT to impact is between that for PETN and RDX, sensitivity to friction is between that for lead azide and PETN, and sensitivity to electric discharge is about the same as for PETN. DANT′s heat of combustion is 2060 kJ mol⁻¹.     

Low‐Cost‐Membranen für die Vanadium‐Redox‐Flow‐Batterie

Vanadium redox‐flow batteries are a technology that can be used to store fluctuating energies from solar and wind power. In order to reduce the manufacturing costs of the batteries, e.g., cheaper raw materials can be used. By using polystyrene‐based polymers for membrane production, conductivities comparable to perfluorosulfonic acid membranes can be achieved. A way to produce these heterogeneous membranes consisting of disperse and continuous phase is shown.     

N‐Alkyl‐, 1‐C‐Alkyl‐, and 5‐C‐Alkyl‐1,5‐dideoxy‐1,5‐imino‐(l)‐ribitols as Galactosidase Inhibitors

A series of 1,5‐dideoxy‐1,5‐imino‐(l )‐ribitol (DIR) derivatives carrying alkyl or functionalized alkyl groups were prepared and investigated as glycosidase inhibitors. These compounds were designed as simplified 4‐epi‐isofagomine (4‐epi‐IFG) mimics and were expected to behave as selective inhibitors of β‐galactosidases. All compounds were indeed found to be highly selective for β‐galactosidases versus α‐glycosidases, as they generally did not inhibit coffee bean α‐galactosidase or other α‐glycosidases. Some compounds were also found to be inhibitors of almond β‐glucosidase. The N‐alkyl DIR derivatives were only modest inhibitors of bovine β‐galactosidase, with IC₅₀ values in the 30–700 μm range. Likewise, imino‐l ‐ribitol substituted at the C1 position was found to be a weak inhibitor of this enzyme. In contrast, alkyl substitution at C5 resulted in enhanced β‐galactosidase inhibitory activity by a factor of up to 1000, with at least six carbon atoms in the alkyl substituent. Remarkably, the ‘pseudo‐anomeric’ configuration in this series does not appear to play a role. Human lysosomal β‐galactosidase from leukocyte lysate was, however, poorly inhibited by all iminoribitol derivatives tested (IC₅₀ values in the 100 μm range), while 4‐epi‐IFG was a good inhibitor of this enzyme. Two compounds were evaluated as pharmacological chaperones for a GM1‐gangliosidosis cell line (R301Q mutation) and were found to enhance the mutant enzyme activity by factors up to 2.7‐fold.     

Studies on ethylene‐propylene‐diene rubber modification by N‐chlorothio‐N‐butyl‐benzenesulfonamide

N‐Chlorothiosulfonamides have been used to modify ethylene‐propylene‐diene rubber (EPDM) to enhance the compatibility of EPDM in, e.g., natural rubber (NR)/butadiene rubber (BR)/EPDM blends for ozone resistance. N‐Chlorothio‐N‐butyl‐benzenesulfonamide (CTBBS) was selected as a representative for N‐chlorothiosulfonamides. In this study, we found that CTBBS behaves differently with various types of EPDM. Three types of EPDM were selected: ethylidene norbornene (ENB)‐EPDM, hexadiene (HD)‐EPDM, and dicyclopentadiene (DCPD)‐EPDM. HD‐EPDM showed the greatest effectiveness toward CTBBS‐modification. However, this EPDM is not commercially available anymore. On the opposite side, DCPD‐EPDM showed the lowest reactivity so that almost no modification could be realized. The result with ENB‐EPDM was, that upon application of CTBBS to ENB‐EPDM, gelation occurred and, therefore, a low amount of modification was achieved. With the limited modification efficiency for ENB‐EPDM, there is no significant improvement when applying the modified ENB‐EPDM into NR/BR/EPDM blends. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Synthesis of 5‐vinyl‐m‐ phenylene‐m′‐phenylene‐32‐ crown‐10 and its radical polymerization behavior

Synthesis of a vinyl monomer, containing a 32‐membered crown ether unit (VCE) as a pendant group, was achieved by using tetra(ethylene glycol) dichloride, resorcinol, and 3,5‐dihydroxyacetophenone as starting materials. The product was identified by means of FTIR and ¹H‐NMR. It was found that this monomer readily polymerizes by the conventional radical initiator 2,2′‐ azobisisobutyronitrile (AIBN) to afford a polymer whose number‐average molecular weight is 36 kg/mol; however, the final conversion of the polymer was < 80%. The results of the copolymerization of VCE with styrene (ST) or acrylonitrile (AN) are also discussed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2372–2379, 2002     

Crystallization behavior of 1,3‐dipalmitoyl‐2‐oleoyl‐glycerol and 1‐palmitoyl‐2,3‐dioleoyl‐glycerol

A model margarine was stored under a temperature fluctuation cycle of 5—20 °C until granular crystals were observed. Using information obtained from the granular crystals, the crystallization behaviors of major triacylglycerols of palm oil, 1,3‐dipalmitoyl‐2‐oleoyl‐glycerol (POP), 1‐palmitoyl‐2,3‐dioleoyl‐glycerol (POO), and their mixtures were then investigated. It was shown that in the model margarine, the POP content in the granular crystals was higher than in their surrounding materials, and the X‐ray diffraction pattern of the granular crystals revealed that they were the most stable polymorph, β. 99% pure POP, POO, and their mixtures were then stored under the above‐mentioned temperature cycle. POP was found to form the unstable polymorph, α, when cooled rapidly from the melt. Within 24 hours transformation into the γ polymorph and then into the β polymorph was observed. POO was shown to transform into the β' polymorph from α. When POP and POO were mixed, the β polymorph did not emerge, instead it was shown that POP and POO were both agglomerated in the mixtures, giving rise to the formation of granular crystals.     

Metal‐ion‐retention properties of the poly(2‐acrylamido‐2‐methyl‐1‐propanosulfonic acid‐co‐4‐vinyl pyridine) resin

The water‐insoluble resin poly(2‐acrylamido‐2‐methyl‐1‐propanosulfonic acid‐co‐4‐vinyl pyridine), through a radical polymerization solution, was synthesized with ammonium persulfate as an initiator and N,N‐methylene bisacrylamide as a crosslinking reagent. The metal‐ion‐retention properties were studied by batch and column equilibrium procedures for the following metal ions: Hg(II), Cu(II), Cd(II), Zn(II), Pb(II), and Cr(III). These properties were investigated under competitive and noncompetitive conditions. The effects of the pH, maximum retention capacity, and regeneration capacity were studied. The resin showed a high retention ability for Hg(II) ions at pH 2.0. The retention of Hg(II) ions from a mixture of ions was greater than 90%. The resin showed a high selectivity for Hg(II) with respect to other metal ions. The Hg(II)‐loaded resin was able to be recovered with 4M HClO₄. The retention capacity was kept after four cycles of adsorption and desorption. The retention properties for Hg(II) were very similar with the batch and column methods. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3556–3562, 2003     

Lewis Acid‐Mediated Transformations of trans‐2‐Aroyl‐3‐aryl‐ cyclopropane‐1,1‐dicarboxylates into 2‐Pyrones and 1‐Indanones

trans‐2‐Aroyl‐3‐arylcyclopropane‐1,1‐dicarboxylates upon treatment with aluminium(III) chloride (AlCl₃) underwent ring‐opening, fragmentation, recombination and lactonization to give highly substituted 2‐pyrones. Alternatively, when treated with titanium(IV) chloride (TiCl₄), the cyclopropane diesters underwent a Nazarov cyclization to afford 1‐indanones with high diastereoselectivity.

     

One‐pot Synthesis of N‐Formyl‐O‐acyl‐ threo‐ and erythro‐DL‐β‐phenylserine Ethyl Esters and their Antiviral Properties

A series of N‐formyl‐O‐acyl‐β‐phenylserine derivatives 1b ‐ 7b were prepared by the interaction of N‐acyl‐b‐phenylserine ethyl esters 1a ‐ 7a with formic acid in presence of 1.5% HF. One‐pot acyl group N → O migration followed N‐formylation under elaborated reaction conditions. The kinetics of the reaction was investigated. The carboxylic acid moiety in the structure of β‐phenylserine had a strong influence on the reproduction of the used test‐viruses. The toxicity and antiviral activity is dependent on the diastereomeric forms of evaluated compounds.     

Recycled‐disposable‐chopstick‐fiber‐reinforced polypropylene green composites

The utilization of disposable chopsticks is very popular in Taiwan, China, and Japan and is one of the major sources of waste in these countries. In this study, recycled disposable chopstick fiber was chemically modified. Subsequently, this modified fiber and polypropylene‐graft‐maleic anhydride were added to polypropylene (PP) to form novel fiber‐reinforced green composites. A heat‐deflection temperature (HDT) test showed an increase of approximately 81% for PP with the addition of 60‐phr fibers, and the HDT of the composite could reach up to 144.8°C. In addition, the tensile strength, Young's modulus, and impact strength were 66, 160.3, and 97.1%, respectively, when the composite material was 40‐phr fibers. Furthermore, this type of reinforced PP would be more environmentally friendly than an artificial‐additive‐reinforced one. It could also effectively reduce and reuse the waste of disposable chopsticks and lower the costs of the materials. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis and Characterization of 1‐Nitroguanyl‐3‐nitro‐5‐amino‐1,2,4‐triazole

The synthesis of 1‐nitroguanyl‐3‐nitro‐5‐amino‐1,2,4‐triazole (ANTA‐NQ) ( 1 ) with good yield and high purity is described. DSC analysis showed that the material displays good thermal stability. An X‐ray crystallographic analysis confirms the structure of this material, as well as displays intramolecular hydrogen bonding. A gas pycnometry density for this material was measured to be 1.79 g cm⁻³. The heat of formation of this material was also measured. These data, along with the molecular formula were used as inputs to calculate the detonation velocity and detonation pressure using the Cheetah thermochemical code. The sensitivity of this material towards impact, spark and friction was also measured, as well as its vacuum thermal stability. The 3‐azido derivative 2 was also prepared and its properties are described as well. The above data show that (ANTA‐NQ) may be a high performing material with low sensitivity and good thermal stability.     

Enzymatic Synthesis of 1‐Alkyl‐2‐hydroxy‐sn‐glycero‐2,3‐cyclic‐phosphate Using a Novel Lysoplasmalogen‐Specific Phopholipase D

Many phospholipase Ds (PLDs) are known to catalyze transphosphatidylation as well as hydrolysis of phospholipids. Transphosphatidylation of lysoplasmalogen (LyPls)‐specific phospholipase D (LyPls‐PLD), which catalyzes hydrolysis of ether lysophospholipids such as LyPls and 1‐hexadecyl‐2‐hydroxy‐sn‐glycero‐3‐phosphocholine (Lyso‐PAF), still remains unclear. This study aims to reveal the transphosphatidylation activity of LyPls‐PLD, that is, the production of cyclic ether lysophospholipid. The enzymatic reaction is conducted in a buffer system, and the reaction products of a novel LyPls‐PLD from Thermocrispum sp. are investigated using mass spectrometry (MS). MS analyses demonstrate the reaction products to consist of 100% 1‐hexadecyl‐2‐hydroxy‐sn‐glycero‐2,3‐cyclic‐phosphate (cLyPA) and choline from Lyso‐PAF; however, 1‐alkenyl‐2‐hydroxy‐sn‐glycero‐2,3‐cyclic‐phosphate from 1‐O‐1′‐(Z)‐octadecenyl‐2‐hydroxy‐sn‐glycero‐3‐phosphocholine and 1‐O‐1′‐(Z)‐octadecenyl‐2‐hydroxy‐sn‐glycero‐3‐phosphoethanolamine is not produced. These results are expected to help in elucidating the catalytic mechanism of LyPls‐PLD, that is, the rate‐limiting step, and indicate LyPls‐PLD to be useful for the one‐pot synthesis of cLyPA. Practical Applications: A novel phospholipase D, LyPls‐PLD, can exclusively synthesize cLyPA from Lyso‐PAF using a one‐step enzymatic reaction without an organic solvent. cLyPA could be expected to show bioactivities similar to those of cyclic phosphatidic acid, which promotes normal cell differentiation, hyaluronic acid synthesis, antiproliferative activity in fibroblasts, and inhibitory activity toward cancer cell invasion and metastasis.     

Lecithin‐enhanced biotransformation of cholesterol to androsta‐1,4‐diene‐3,17‐dione and androsta‐4‐ene‐3,17‐dione

A biotransformation process using Mycobacterium sp was studied for androsta‐1, 4‐diene‐3,17‐dione (ADD) and androsta‐4‐ene‐3,17‐dione (AD) production from cholesterol. Cholesterol has a poor solubility in water (～1.8 mg dm^?3 at 25 °C), which makes it difficult to use as the substrate for biotransformation. Lecithin is a mixture of phospholipids of phosphatidylcholine (PC) and phosphatidylethanolamine (PE), which behave like surfactants and can form planar bi‐layer structures in an aqueous medium. Therefore, a small amount of lecithin (<1 g dm^?3) can be used to form stable colloids with cholesterol at a relatively high concentration (20 g dm^?3) in water. In this work, an energy density of 1000 J cm^?3 from sonication was provided to overcome the self‐association of cholesterol and to generate a stable lecithin–cholesterol suspension that could be used for enhanced biotransformation. The lecithin–cholesterol suspension was stable and could withstand typical autoclaving conditions (121 °C, 15 psig, 20 min). In contrast to conventional surfactants, such as Tween 80, that are commonly used to help solubilize cholesterol, lecithin did not change the surface tension of the aqueous solution nor cause any significant foaming problem. Lecithin was also biocompatible and showed no adverse effect on cell growth. Compared with the medium with Tween 80 as the cholesterol‐solubilizing agent, lecithin greatly improved the biotransformation process in regard to its final product yield (～59% w/w), productivity (0.127–0.346 g dm^?3 day^?1), ADD/AD ratio (6.7–8), as well as the long‐term process stability. Cells can be reused in repeated batch fermentations for up to seven consecutive batches, but then lose their bioactivity due to aging problems, possibly caused by product inhibition and nutrient depletion. © 2002 Society of Chemical Industry     

1‐amino‐4,5‐8‐naphthalenetricarboxylic acid‐1,8‐lactam‐4,5‐imide‐containing macrocycles: synthesis,molecular modelling and polymerization

Novel macrocycles containing 1‐amino‐4,5‐8‐naphthalenetricarboxylic acid‐1,8‐lactam‐4,5‐imide and 1,4,5‐8‐naphthalenetetracarboxylic bisimide fragments were synthesized by the high‐temperature pseudo‐high‐dilution acylation of the corresponding diols with isophthaloyl chloride, 4,4′‐ and 2,2′‐dichlorocarbonyl biphenyls with up to 60% yield. An important side‐reaction that impedes cyclization was found to be the reaction of diol OH groups with HCl during the acetylation. The ring strain in synthesized macrocyles and model cycles was estimated using the isodesmic reaction approach at the B3LYP/6–311 + G(d,p)//HF/3–21G level of theory. Lactamimide‐containing macrocycles were found to be more strained than bisimide‐containing macrocycles. The ring‐opening polymerization (ROP) of synthesized macrocycles in the molten state shows that the driving force of this process is the strain release on ring‐opening. The ROP of lactamimide‐containing macrocycles was found to be an efficient way to obtain lactamimide‐containing polymers, which are otherwise difficult to synthesize. Copyright © 2003 Society of Chemical Industry     

But‐2‐ene‐1,4‐diamine and But‐2‐ene‐1,4‐diol as Donors for Thermodynamically Favored Transaminase‐ and Alcohol Dehydrogenase‐Catalyzed Processes

Both cis‐ and trans‐but‐2‐ene‐1,4‐diamines have been prepared and efficiently applied as sacrificial cosubstrates in enzymatic transamination reactions. The best results were obtained with the cis‐diamine. The thermodynamic equilibrium of the stereoselective transamination process is shifted to the amine formation due to tautomerization of 5H‐pyrrole into 1H‐pyrrole, achieving high conversions (78–99%) and enantiomeric excess (up to >99%) by using a small excess of the amine donor. Furthermore, when the reaction proceeded, a strong coloration was observed due to polymerization of 1H‐pyrrole. A structurally related compound, cis‐but‐2‐ene‐1,4‐diol, has been utilized as cosubstrate in different alcohol dehydrogenase (ADH)‐mediated bioreductions. In this case, high conversions (91–99%) were observed due to a lactonization process. Both strategies are convenient from both synthetic and atom economy points of view in the production of valuable optically active products.

     

Crystallization Behavior of Molecular Compound in Binary Mixture System of 1,3‐Dioleoyl‐2‐Palmitoyl‐sn‐Glycerol and 1,3‐Dipalmitoyl‐2‐Oleoyl‐sn‐Glycerol

Previous studies showed that the stable β‐form of molecular compound (MC) crystals having a double‐chain‐length structure is formed in a binary mixture system of 1,3‐dioleoyl‐2‐palmitoyl‐sn‐glycerol (OPO) and 1,3‐dipalmitoyl‐2‐oleoyl‐sn‐glycerol (POP) with a 1:1 concentration ratio of OPO and POP. The use of MC crystals made of POP and OPO for edible applications, such as margarine, is advantageous due to no‐trans, low‐saturated, and high‐oleic fats. Industrial manufacturing technology involves rapid cooling processes, and the kinetic properties of crystallization of MC of OPO and POP are required. In this study, we clarified the crystallization of MC of OPO and POP under rapid cooling at rates of 1–150 °C min^?1, using synchrotron radiation time‐resolved X‐ray diffraction and differential scanning calorimetry methods. The main results are as follows: (1) POP and OPO crystallized in separate manners without the formation of MC crystals under rapid cooling (>40 °C min^?1), while MC crystals started to form with decreasing rates of cooling in addition to the POP and OPO crystals (<30 °C min^?1); (2) metastable and stable forms sub‐α, α, β′, and β of POP and OPO were formed, whereas the MC crystals of β were formed during the cooling processes; and (3) the heating processes after crystallization by rapid cooling caused separate melting of the metastable and stable forms of POP and OPO crystals and the formation of MC crystals of β made of POP and OPO, as well as melting of the MC crystals alone.     

An Ab Initio Theoretical Study of 2,4,6‐Trinitro‐1,3,5‐Triazine, 3,6‐Dinitro‐1,2,4,5‐Tetrazine,and 2,5,8‐Trinitro‐Tri‐s‐Triazine

In order to evaluate 2,4,6‐trinitro‐1,3,5‐triazine (TNTAz), 3,6‐dinitro‐1,2,4,5‐tetrazine (DNTAz), and 2,5,8‐trinitro‐tri‐s‐triazine (TNTsTAz), the geometries of these compounds have been fully optimized employing the B3LYP density functional method and the AUG‐cc‐pVDZ basis set. The accurate gas phase enthalpies of formation have been obtained by using the atomization procedure and designing isodesmic reactions in which the parent rings are not destroyed. Based on B3LYP/AUG‐cc‐pVDZ calculated geometries and natural charges, the crystal structures have been predicted using the Karfunkel–Gdanitz method. Computed results show that there exists extended conjugation over the parent rings of these compounds. More energy content is reserved in DNTAz than in both TNTAz and TNTsTAz. The title compounds are much more sensitive than 1,3,5‐trinitrobenzene. The calculated detonation velocity of DNTAz reaches 9.73–9.88 km s⁻¹, being larger than those of CL‐20 and TNTAz. TNTsTAz has no advantage over the widely used energetic compounds such as RDX and HMX.