An overview of the synthesis of acyl hydrazides from aldehydes and reactions of the products thereof

Herein a review on the methods for the formation and reaction of acyl hydrazides will be given. There is particular focus on the synthesis of acyl hydrazides from aldehyde precursors with examination of the various approaches (e.g. metal-based (rhodium, copper) and non-metal-based (aerobically- and photoorganocatalytically-initiated)) that have been used to achieve this. Finally, strategies to utilise acyl hydrazides for the formation of an array of useful entities will be detailed

Formation of Synthetically Versatile 2-Aminobenzophenones from Readily Accessed Acyl Hydrazides

Herein, we report the transformation of readily accessed acyl hydrazides into protected 2-aminobenzophenones via a two-step process involving an aryne-based molecular rearrangement followed by a one-pot addition-elimination procedure. The assembly of the scaffold is tolerant of a wide variety of functional groups, and the carbamate group on the product can be facilely removed to afford highly valuable 2-aminobenzophenones. Application of the protocol was demonstrated in the synthesis of neurological medicine phenazepam

Fine-tuning thio-pyridazinediones as SMDC scaffolds (with intracellular thiol release via a novel self-immolative linker)

Herein we report the synthesis of a library of thioalkyl- and thioaryl-pyridazinediones for thiol-based self-immolative release of cargo. A bisthioaryl-pyridazinedione is shown to be stable to serum protein albumin but unstable in intracellular conditions. A derivatised analogue underwent self-immolative degradation in cellular thiol conditions as evidenced by LC-MS/release of a turn-on fluorescence fluorophore; versatility of the thiol-pyridazinedione is demonstrated through synthesis of SMDC precursors that contain three different functional groups on the same central molecule

Semantically Adversarial Learnable Filters

We present an adversarial framework to craft perturbations that mislead classifiers by accounting for the image content and the semantics of the labels. The proposed framework combines a structure loss and a semantic adversarial loss in a multi-task objective function to train a fully convolutional neural network. The structure loss helps generate perturbations whose type and magnitude are defined by a target image processing filter. The semantic adversarial loss considers groups of (semantic) labels to craft perturbations that prevent the filtered image from being classified with a label in the same group. We validate our framework with three different target filters, namely detail enhancement, log transformation and gamma correction filters; and evaluate the adversarially filtered images against three classifiers, ResNet50, ResNet18 and AlexNet, pre-trained on ImageNet. We show that the proposed framework generates filtered images with a high success rate, robustness, and transferability to unseen classifiers. We also discuss objective and subjective evaluations of the adversarial perturbations

Effects of tillage methods and sowing rates on the grain yields and yield components of rain fed wheat

A field study was conducted on the effect of four primary tillage implements and three seed densities on the grain yield of rain fed wheat (Tajan cultivar), using a drill planting machine with the end wheels. The experimental design was a split plot design in a 4×3 factorial with three replications. In this study, the main plots were the tillage treatments, namely Mouldboard plough, Disc Plough, Chisel Plough, Offset Disc, and sub-plots were seed rates of 350, 400 and 450 seeds.m-2-2 sowing rate, had the highest grain yield of wheat grown in the Golestan province (Iran), a region with an average annual rainfall of 450 mm

Induction of mammary gland tumor in female Sprague- Dawley rats with LA7 cells

The current methods for tumor induction in breast cancer research animal models are time-consuming, hazardous, expensive, sometimes irreproducible and inconvenient. We successfully developed a new, simple and cost-effective method in developing solid mammary gland tumor in female Sprague-Dawley rat using LA7 rat mammary tumor cells. Tumors developed in 7- 8 weeks old rats within 6 to 8 days of subcutaneous injection of LA7 cells into the mammary gland pad. Tumor size increased exponentially for four weeks. Histopathology examination confirmed that the induced tumors were adenocarcinomas. Evaluation of blood enzymes showed significantly higher (P < 0.005) serum alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) in tumor-bearing than in normal rats. This LA7 cell-induced rat mammary gland tumor model may be useful for studies in breast cancer drug or nutraceutical research and development

Understanding the structure and dynamics of cationic surfactants from studies of pure solid phases

A homologous series of n-alkyl trimethylammonium bromide surfactants, H(CH2)nN+(CH3)3 Br, from C10TAB to C18TAB have been studied systematically in the bulk over a wide range of temperatures. Common features in the structures are identified, with packing dominated by the co-ordination of the cationic head groups with bromide anions and interdigitation of the hydrocarbon chains. This arrangement provides an explanation for the thin adsorbed bilayers that have been observed at various hydrophilic surfaces from aqueous solutions in previous studies. The molecular volumes and arrangement are comparable with structures of a number of different self-assembled amphiphiles. For these surfactants with bromide counter-ions, formation of crystal hydrates was not observed. The alkyl chains are highly mobile and at high temperatures a plastic phase is found for all materials with a transition enthalpy that is similar to the melting enthalpy of many long alkyl chains. Other unexpected phase transitions depend more markedly on the hydrocarbon chain length and evidently depend on delicate balances of the various contributions to the free energy

A facile route to 1H- and 2H-indazoles from readily accessible acyl hydrazides by exploiting a novel aryne-based molecular rearrangement

Herein we report the transformation of readily synthesised acyl hydrazides into 2-hydrazobenzophenones via a novel molecular rearrangement pathway using aryne chemistry. The developed reaction protocol is performed under relatively mild conditions and is tolerant of a wide variety of functional groups, and the 2-hydrazobenzophenone products provide access to both 1H- and 2H-indazoles from a single intermediate

Pattern of mandibular third molar impaction: A cross‑sectional study in northeast of Iran

Objectives: Impacted teeth, if left untreated, have a potential to induce various complications. The aim of the current study was to determine the prevalence and pattern of impacted mandibular third molar in the Iranian population.Study Design: This cross‑sectional study was performed in patients who were referred to the Department of Oral Radiology between July 2009 and October 2010 to obtain an orthopantomogram (OPG). Data were collected regarding age and gender, prevalence of impacted mandibular third molars, angulation of impacted teeth (Winter’s classification), level of impaction (Pell and Gregory classification), and relationship of the mandibular third molar with the ramus (Pell and Gregory classification). The collected data were analyzed using SPSS software version 11.0 with a confidence interval of 95%.Results: Among the 1433 patients included in the study, 489 (34.12%) patients were male and 944 (65.88%) were female. Of the total OPGs performed, 871 (60.78%) OPGs demonstrated at least one impacted mandibular third molar. In addition, of the 2866 mandibular third molars investigated, 1397 (48.74%) were found to be impacted. A significant association was observed between gender and the number of impacted teeth or the presence of impaction of any mandibular tooth (or teeth) (P < 0.05). The most common type of tooth angulation was mesioangular (48.67%). In addition, the most prevalent type of impaction level and ramus relationship was level B (63.85%) and Class II (48.46%), respectively. There were no significant differences between the two sides of the mandible for the prevalence of impacted third molar (P > 0.05).Conclusion: The pattern of mandibular third molars in the Northeast region of Iran revealed a high prevalence of impaction, which was mostly mesioangular, level B, and Class II with a gender predilection for females.Keywords: Impaction, Iran, mandibular third molar, orthopantomogram, patter

Molecular Dynamics Insights into the Structural and Water Transport Properties of a Forward Osmosis Polyamide Thin-Film Nanocomposite Membrane Modified with Graphene Quantum Dots

An approach combining molecular dynamics (MD) simulations and laboratory experiments was applied to provide new theoretical insights into the chemical structure of polyamide (PA) thin-film composite (TFC) membranes modified with graphene quantum dots (GQDs). Interaction energies, fractional free volumes, mean-square displacements, densities, and water diffusion coefficients were computed for PA and four likely chemical structures of the GQD-embedded PA membranes. These theoretical results aided with experimentally measured water fluxes allowed for determining the most likely structure of the GQD-PA membrane. The compatibility of the GQDs and PA chains was found to be due to the formation of hydrogen and covalent bonds to m-phenylenediamine units. The modified membrane has a higher water diffusivity but a lower overall free volume, compared to the pristine PA membrane. MD simulations in concert with laboratory experiments were found to provide a good understanding of the relationship between the microscopic characteristics and macroscopic transport properties of TFC membranes