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In the title compounds, N,N-dimethylacetamide–1-(dimethyl-λ4-azanylidene)ethan-1-ol tribromide (1/1), C4H9NO·C4H10NO+·Br3− or [(C4H9NO)·(C4H10NO)](Br3), (I), N,N-dimethylacetamide–1-(dimethyl-λ4-azanylidene)ethan-1-ol dibromidoiodate (1/1), C4H9NO·C4H10NO+·Br2I− or [(C4H9NO)·(C4H10NO)](Br2I), (II), and N,N-dimethylacetamide–1-(dimethyl-λ4-azanylidene)ethan-1-ol dichloridoiodate (1/1), C4H9NO·C4H10NO+·Cl2I− or [(C4H9NO)·(C4H10NO)]·(Cl2I), (III), all the anions are almost linear in geometry and all the cations, except for the methyl H atoms, are essentially planar. In the crystal structure of (I), the cations are linked by pairs of C—H...O hydrogen bonds, forming inversion dimers with an R22(8) ring motif. These dimers also exhibit O—H...O hydrogen bonding. Dimerized cation pairs and anions are arranged in columns along the a axis. In the crystal of (II), the cations are linked by pairs of O—H...O and C—H...O hydrogen bonds, forming an R44(14) ring motif. These groups of cations and the anions form individual columns along the a axis and jointly reside in planes roughly parallel to (011). In the crystal of (III), cations and anions also form columns parallel to the a axis, resulting in layers parallel to the (020) plane. Furthermore, the crystal structures of (I), (II) and (III) are consolidated by strong halogen (Br and/or I and/or Cl)...H and weak van der Waals interactions. In addition to the structural evaluation, a Hirshfeld surface analysis was carried out.

The key role of a cryoprotectant is to minimize the chemical and physical stress which occurs during cooling, freezing and thawing of semen. The difference between the cryoprotectant (CPA) occurs in their permeability coefficient and the structural model of the cryogenic agent. The beneficial effect of dimethylacetamide (DMA) as a cryoprotectant especially for sperms had been observed in several studies. The aim of the study was to study the cryoprotective effect of DMA in freezing the Malabari buck semen compared to glycerol. Ten ejaculates were taken from fourMalabaribucks . After preliminary evaluation sample split technique was followed with Tris based extender containing glycerol (6.7 per cent) as cryoprotectant (control) and Trisextender containing DMA (3 per cent) as cryoprotectant (treatment group). The semen straws (0.25mL) after filling were subjected for equilibration and manual freezing. Sperm kinetics was studied using computer-aided sperm analyzer. Pre-freeze and post-thaw evaluation included sperm viability, sperm abnormality, hypo osmotic test, acrosome integrity test and DNA fragmentation. Results indicated that inclusion of 6.7 per cent glycerol had significantly higher (p

ABSTRACT: The present study evaluated the cryoprotectant efficacy of dimethylacetamide (DMA) and ethylene glycol in a one-step protocol to freeze boar sperm. The sperm-rich portion of the ejaculates from two boars were collected once a week, for 10 weeks. After collection, the ejaculates were diluted (1:1; v/v) in the cooling extender. After determining their spermatozoa concentration, the ejaculates were pooled with the same number of spermatozoa from each boar and stabilized at 20°C for 120 min. Distinct cryoprotectants were added to the cooling extender at 20 °C, at different concentrations, composing six treatments: 1.25% and 2.5% glycerol (control); 1.25% and 2.5% ethylene glycol; 2.5% and 5.0% DMA. The samples were stored in 0.25 mL straws, containing 35 × 106 spermatozoa. After 90 min at 20 °C, the straws were submitted to a cooling curve until 5 °C (0.3 to 0.5 °C/min) and kept at 5°C for 60 min. Freezing was conducted by placing the straws horizontally 5 cm above the liquid nitrogen for 10 min, followed by immersion on liquid nitrogen. After thawing at 37 °C for 30 seconds, sperm quality was evaluated through a computer-assisted semen analysis system and flow cytometry. Sperm motility was greater (P< 0.05) in treatments with 5.0% and 2.5% DMA (22.2 ± 2.6% and 20.0 ± 2.8%, respectively) than in treatment with 2.5% ethylene glycol (8.2 ± 1.0%). The integrity of the plasma membrane (P = 0.08) and mitochondrial membrane potential (P = 0.27) was similar among the treatments. The treatment with 2.5% ethylene glycol was the least efficient to maintain intact acrosome membrane (P< 0.01). Some kinetics parameters (DAP, DCL, DSL, VAP, VCL, VSL e ALH) were positively affected by 5.0% DMA. The one-step freezing protocol resulted in unsatisfactory boar sperm motility after thawing, regardless of the cryoprotectant.

The mechanical recycling method of the carbon fiber-reinforced polymer (CFRP) has the advantages of simple process, less pollution and low cost, but only low utilization value of carbon fibers in powder or short fibers form can be obtained. To reduce the length and strength loss of the recycled carbon fibers, a novel and cost-effective dimethylacetamide (DMAC) swelling technique was developed to achieve rapid delamination of the CFRP laminates under mild conditions (120°C–160°C, 1 h). The corresponding swelling ratios and mass-loss rates of cured epoxy resin (CEP) were about 121.39%–157.39% and 0–0.69%, respectively. Excessive swelling of CEP in DMAC resulted in the cracking of the resin matrix between the adjacent carbon fiber layers. Thus the CFRP laminates were delaminated into soft single carbon fiber layers, which showed excellent cutting performance and reinforcing properties. The delamination products were cut into thin strips of different sizes and vacuum bag molded into new CFRP laminates. The flexural strength and tensile strength of the newly produced CFRP laminates were about 76.38%–90.98% and 94.61%–98.54% of the original CFRP laminates, respectively. More importantly, the chemical compositions of DMAC and CEP were unchanged during the physical swelling process. No organic pollutants (caused by resin degradation) were generated. And the used DMAC can be easily recycled by filtration. Therefore, this study provides a strategy for low-cost and high-valued recycling of CFRP waste.

Sperm cryopreservation is an effective technique for conserving animal genetic diversity and transmitting superior genetic backgrounds, maintained via a non-invasive sampling and collection of huge quantities of sperm. Nevertheless, cryopreservation in avian species is not commercially viable because of the rooster sperm’s susceptibility to damage. This study aims to estimate the impact of dimethylacetamide (DMA) as a cryoprotectant at different levels (3%, 6%, or 9%) on the post-thawed sperm quality, motility, antioxidant-biomarkers, and the expression of anti-freeze related genes. Semen samples were collected twice a week from twelve roosters aged 40 wk, weighing 3400 ± 70 g, and belonging to the Cairo-B2 chicken strain. Fresh semen samples were rapidly appraised, pooled, diluted with two volumes of a basic extender, and divided equally into three groups. The diluted groups were chilled at −20 °C for 7 min, then gently supplemented with 3, 6, or 9% pre-cooled DMA and equilibrated at 5 °C for a further 10 min. Semen pellets were formed by pipetting drops 7 cm above liquid nitrogen (LN2), which were then kept inside cryovials in the LN2. Thawing was performed 2 months later by taking 3–4 pellets of the frozen semen into a glass tube and warming it in a water bath for 8 s at 60 °C. The results showed that 3% DMA increased the proportion of total motile sperm, progressivity, viability, and plasma membrane integrity (%) compared to the 6% and 9% DMA groups. The lipid peroxidation and antioxidant enzyme activity were improved in the 3% group. At the same time, some anti-freeze-related genes’ (including ras homolog family member A (RHOA), heat shock protein 70 (HSP70), and small nuclear ribonucleoprotein polypeptide A (SNRPA1)) expressions were upregulated within the 3% DMA group relative to other groups. In conclusion, the 3% DMA group maintained higher post-thawed sperm quality than the other tested groups.

Wastewater from factories producing polysulfone-based membranes mainly contains the used organic solvent, i.e., dimethylacetamide (DMAc). Due to the environmental impact of DMAc, wastewater treatment is mandatory. Several biological treatment options based on the activated sludge process are described in the literature. Due to artificial aeration, these techniques have high energy requirements. Near-nature processes such as vertical flow constructed wetlands (VF wetlands) have a low energy demand, high tolerance to load fluctuations, and low maintenance requirements. Therefore, high-loaded, two-stage VF wetlands are an efficient option for treating wastewater. However, constructed wetlands have so far only been used to a limited extent for the treatment of industrial wastewater. In the present study, the ability of laboratory-scale, high-load, two-stage VF wetlands to treat DMAc was investigated. This included their DMAc degradation efficiency and corresponding pathways, removal of the total organic carbon (TOC), nitrification and denitrification of the nitrogen, as well as the ecotoxicological effects (mutagenicity, genotoxicity, reactive oxygen species) of untreated and treated wastewater. The focus was to determine the effect of different grain size distributions on removal rates, the maximum inflow loading, and the effect of high inflow concentrations on effluent concentrations. In general, DMAc was completely degraded using VF wetlands, with dimethylamine (DMA) identified as the main intermediate. TOC removal rates reached more than 99%. The nitrogen bound to DMAc was completely nitrified. However, the start-up of the VF wetlands without seeded filter material temporarily leads to high nitrite accumulation. This may affect the mutagenicity of the treated wastewater. The results show that high-loaded, two-stage VF wetlands are an effective option for treating wastewater containing DMAc with higher efficiency than comparable biological processes.

The alkyl and aryl derivatives of aniline are important starting materials in fine organic synthesis. Allyl bromide and benzyl chloride were taken as substrates for the alkylation reaction and as a halide ion scavenger. Triethylamine was utilized at reflux condition of N,N-dimethylacetamide (DMA). Novel synthesized N-benzyl and N-allyl aniline derivatives (1a-f) were evaluated to be highly potent inhibitors for acetylcholinesterase (AChE) and carbonic anhydrases (hCAs). The half maximal inhibitory concentration (IC50) of N-benzyl- and N-allyl aniline derivatives were calculated between 243.11 and 633.54 nM for hCA I, 296.32–518.37 nM for hCA II and 182.45–520.21 nM for AChE enzymes. On the other hand, Ki values are in the range of 149.24 ± 15.59 to 519.59 ± 102.27 nM for AChE, 202.12 ± 16.21 to 635.31 ± 45.33 nM for hCA I and 298.57 ± 94.13 to 511.18 ± 115.98 nM for hCA II isoenzyme. Additionally, in silico molecular docking computations were performed with Autodock Vina program to support the experimental in vitro studies for both hCAs and AChE inhibitors. The in silico molecular docking results demonstrated that the scores are in good agreement with the experimental results.

Sperm cryopreservation is of great importance for the poultry industry but still needs to be optimized. The high susceptibility of poultry sperm to cryodamage leads to low fertility rates after cryopreservation. Therefore, the present study aimed at evaluating the effect of including a cryoprotectant, dimethylacetamide (DMA), in the chicken semen freezing extenders at a final concentration of 3%, 6%, or 9% on the post-thawed sperm motility, quality, antioxidant biomarkers, anti-freeze gene expression, and fertilizing ability. Results showed that the total motile sperm, progressivity, and viability were quadratically increased (p < 0.05) in the 6% DMA group. The antioxidant enzyme activity and lipid peroxidation were negatively (p < 0.05) affected by the increase in DMA concentration. Furthermore, some anti-freeze-associated genes such as heat shock protein 70 (HSP70) and ras homolog family member A (RHOA) were linearly and quadratically down-regulated (p < 0.05) with the high concentration of DMA. Finally, the fertility and hatchability rates did not indicate statistical differences between DMA groups. It can be concluded that using the low concentration of 3–6% DMA in the freezing semen extender is preferable to obtain acceptable results in the post-thawed sperm quality and fertility.

ABSTRACT: Chicken semen cryopreservation is a tool for programs of genetic diversity management and endangered breeds conservation. Due to physiological features, the fertility rates of cryopreserved poultry sperm are lower than mammal species. Thus, improvement of the semen cryopreservation methods is required. A first study was performed by a 2 × 2 factorial design consisting of 2 methods of adding the cryoprotectant [Direct or Diluted (mixed with extender medium)] and 2 cryoprotectants (glycerol and dimethylacetamide). Then sperm quality indicators were evaluated after freezing. A second study with a 2 × 2 design was conducted to evaluate the effectiveness of bovine serum albumin (BSA) on the optimization of 2 different extenders (Lake and Animal Sciences Group [ASG]). Viability and motility variables were evaluated before and after freezing. There was no significant difference in sperm viability and motility variables between Direct or Diluted methods. Supplementation of extenders with BSA improved most of the sperm motility variables in both extenders before and after freezing. Progressive sperm, non-progressive sperm before freezing, and all post-thaw sperm motility parameters, except amplitude of lateral head displacement and beat-cross frequency, were increased in BSA-supplemented extenders (P < 0.05), and BSA improved sperm viability in ASG extender after thawing (P < 0.05). After thawing, the interaction between extender and BSA (P < 0.05), eliminated the differences between the 2 BSA-supplemented media in curvilinear velocity, straight-line velocity, average path velocity, and amplitude of lateral head displacement which were higher in non-supplemented ASG extender than nonsupplemented Lake medium. In conclusion, the direct or diluted methods of adding glycerol or dimethylacetamide, did not significantly affect the post-thaw sperm characteristics. BSA positively affected most of the post-thaw sperm motility indicators regardless of the type of extender and resulted in significantly higher post-thaw sperm viability in ASG medium.

The treatment of aryl amines with dimethylformamide (DMF) and dimethylacetamide (DMA) in the presence of hydrochloric acid brings about efficient N-acylation to give the corresponding aryl formamides and aryl acetamides in acceptable to excellent yields. This method is simple, general, and practical for the rapid construction of aryl formamide and aryl acetamide derivatives.

Rhodium(I)-complex [Rh(CO)2I2−] (1) catalyzed two carbonylations of methyl iodide and trimethylamine in NMP (1-methyl-2-pyrolidone) to acetic acid and DMAC (N,N-dimethylacetamide) in the presence of calcium oxide and water. The carbonylation of trimethylamine continued during the carbonylation and consumption of methyl iodide. In total, 183.8 mmol of carbonylated products was produced while consuming 24.1 mmol methyl iodide via acetic acid formation. These results clearly indicated that there were two carbonylation routes of trimethylamine and methyl iodide and the carbonylation rate of trimethylamine was faster than that of methyl iodide. Rhodium(I)-complex [Rh(CO)2I2]− (1) in the presence of trimethylamine was stable enough to be used 25 times with TON (Turnover Number) of 368 for DMAC and TON of 728 for trimethylamine. Inner-sphere reductive elimination in stepwise procedure was suggested for the formation of DMAC instead of acyl iodide intermediate under anhydrous condition.

The structure of catena-poly[[potassium-tri-μ-dimethylacetamide-κ6O:O] iodide], {[K(C4H9NO)3]I}n, at 120 K has trigonal (P-3) symmetry. The structure adopts a linear chain motif parallel to the crystallographic c axis. Two crystallographically independent K+ cations are present in the asymmetric unit located on threefold rotoinversion axes at [0, 0, 0] and [0, 0, 1/2] and are bridged by the O atoms of the acetamide moiety. This is an example of a rare μ2-bridging mode for dimethylacetamide O atoms. The iodide counter-ion resides on a threefold rotation axis in the channel formed by the [K(C4H9NO)]+ chains.

Dimethylacetamide (DMMA) is used as a solvent for drug preparations, DMAA and its metabolites Monome thy lacetamide (MMAA) and acetamide (AA) cause hemolysis in concentrations above 100 (DMAA), 44 (MMAA) and 40 (AA) mg/ml blood respectively. The effects are double to three times stronger than after distilled water. Dimethylation in the animal body after treatment is followed by an increase of the hemolytic activity. Concentrations after therapeutic use in vivo are as high as the concentration in vitro in hemolysis activity.