Reactivity of styrylmalonates as synthetic equivalents of Donor–acceptor cyclopropanes with aldehydes in the presence of BF3•Et2O
Donor–acceptor cyclopropanes (DACs), which can act as sources of 1,2- and 1,3-zwitterions in the presence of Lewis acids, are widely used in organic synthesis for the preparation of various carbo- and heterocyclic compounds, including natural compounds and their analogues. To date, many types of DACs reactivity have been identified. However, the chemistry of styrylmalonates (isomers of DACs, which can be easily generated from DACs) is almost undescribed and has a powerful synthetic potential. The use of styrylmalonates as synthetic equivalents of DACs allows us cardinally change the known reaction pathways of DACs. In this work, a new strategy for cascade assembly of substituted pyrenes based on the reactions of styrylmalonates with aldehydes in the presence of BF3•Et2O has been developed. Generation of formal 1,2-zwitterionic intermediates owing to complexation of dicarboxylate groups with BF3•Et2O is the driving force of the reaction discovered. This method makes it possible to assemble pyrenes or 5,6-dihydro-2H-pyran-2-ones in one synthetic stage from readily available starting compounds with high regio- and diastereoselectivity, and use these pyrenes in futher reactions. We’ve optimized conditions of the reaction and synthesized a number of various substituted pyrenes. Moreover, the reaction shows good results with various aromatic and heteroaromatic substituents. Pyrenes can be easily purified by crystallization. Every product was obtained selectively and determined by full set of physical-chemical methods, including X-ray analysis. 5,6-dihydro-2H-pyran-2-one skeleton is found in various natural compounds demonstrating a broad spectrum of biological activity, such as antiviral and antineoplastic.
Understanding the Modern Diagnoses of Protein C Deficiency "Pcd" with Unknown Gene Plays a Critical Role in the Inherited Thrombophilia
Protein C deficiency (PCD) is found in 1 out of 200 to 500 persons in the general global population which is also one of the common conditions of Inherited thrombophilia, it’s characterized by an increased tendency of blood to clot in human blood vessels. It is caused by several factors including mutations in the genes involved in thrombin binding, protein c activation and numerous clotting factors. This includes F5 (Factor 5 Leiden) gene on chromosome 1q24.2, F7 (Prothrombin) gene on chromosome 13q34, SERPINC1 (serpin peptidase inhibitor C) on chromosome 1q25.2, SERPIND1 (serpin peptidase inhibitor D) on chromosome 22q11.21, HRG (Histidine Rich Glycoprotein) on chromosome 3q27.3, PLAT (Plasminogen Activator) on chromosome 8q11.21 and THBD (Thrombomodulin) gene on chromosome 20p11.21. In the current study, a three Saudi families with inherited thrombophilia has been recruited to identify the underlying cause of this special condition. Whole exome sequencing, targeting all coding exons of the human genome, was performed using Illumina Nextera library preparation kits followed by paired-end sequencing on Illumina NextSeq500 instrument. Reads quality control was performed and reads were aligned to the reference genome using BWA software. Variants calling and annotation was performed using GATK. All known genes involved in causing inherited thrombophilia All known genes involved in causing PCD were excluded by whole exome sequencing. The genes that were previously reported to be involved in inherited thrombophilia were checked for any causative variant. No mutation has been identified in known genes. identifying a novel gene underlying PCD. The Result of this study will hopefully pave the way to better understanding the disease pathophysiology and help in developing DNA based diagnosis, carrier screening and somatic gene therapy.
How to spill your coffee
We all do it – walk along with a cup in hand, and carelessly spill it. While it’s usually more annoying than anything else, it happens to affect almost all of us, and little is done to minimise the likelihood of it occurring. So my aim was to explain the physics behind why we spill drinks when we walk, and to investigate how we can minimise the likelihood of this occurring. I broke this investigation into two distinct parts, explaining the system of the cup, and explaining the effect of walking. From initial observations, it was clear that the cup was a resonating system. Like any resonating system, the cup has a natural frequency. When the cup is oscillated – moved back and forth – at near this frequency, the size of the liquid oscillations is very large. This is because the acceleration is in phase with the motion of the liquid, so in each cycle maximum energy is input into the system. In my investigation I experimentally measured this natural frequency, and created a mathematical model to explain this frequency. It was also found that as the size of liquid oscillations in the cup increases, so does distortion of the fluid surface, possibly enabling spilling. To systematically analyse the effect of walking, I had subjects walk on a treadmill, so walking surface and speed were controlled. However, I also needed an accurate way of measuring the motion of a carried cup. Firstly, I tried to use video analysis; however I found this far too imprecise for measuring small changes in velocity of a cup. In the end I used a smartphone to record the acceleration of a carried cup, as acceleration is what causes the movement of liquid in a cup. This allowed surprisingly accurate measurements to be made, and allowed both the size and frequency of the acceleration to be recorded. In order to relate the system of the cup and the oscillation provided whilst walking I conducted a qualitative experiment into the effect of stride frequency on the likelihood of spilling. When stride frequency was very close to the natural frequency of the cup, spilling occurred almost instantly, while it did not occur if stride frequency was much higher or lower. In the end, my research showed that to minimise the likelihood of spilling your drink walk slowly, use a narrow cup, focus on walking smoothly, and fill the cup well below the rim. Despite this, some people happen to be much smoother cup carriers than others, likely due to their individual biomechanics. And, if you really don’t want to spill your drink, you can always use a lid.
The Locus of Mid-Tangent Points of Planar Curves
In this project, we defined a mid-tangent point with respect to a fixed point X and a tangent at a point Y on a planar curve C as a point on the tangent that is equidistant from X and Y. We studied the locus of mid-tangent points of conic sections. We found that the locus of mid-tangent points of most conic sections are non-linear curves. However, we observed and proved by using Euclidean geometry that the locus of mid-tangent points of circles are straight lines. The mapping defined by mid-tangent points was studied further. The similarity between a mid-tangent mapping and a stereographic projection was displayed as a one – to – one correspondence function. We also extended the concept of mid-tangent points to three dimensional space and found that the similarity with the stereographic projection was retained in higher dimensions. Finally, we studied the locus of mid-tangent points of a sphere to create a mapping of the sphere to a plane.
Investigating the Effect of Coloured Light on the Behaviour and Learning of Lymnae stagnalis
Lymnae stagnalis (pond snail) is emerging as a preferable invertebrate model in understanding neurological mechanisms because of its simple nervous system. A three-cell network mediates behaviours such as aerial respiration and research has shown that small, subtle changes occurring across the network might result in a disruption of natural behaviour (Lukowiak et al. 1995). It is also known that Lymnae features a more developed eye than other molluscs and studies have shown that various wavelengths of light can activate photoreceptors producing distinct electrophysiological responses (Sakakibara et al. 2004). However, no studies have looked beyond the electrophysiological response. The purpose of this project was to determine if coloured light would firstly, elicit a behavioural response as observed in its movement and secondly, affect learning and memory through the operant conditioning of its aerial respiration.
SeedBot: Low-Cost Seeding Robot for Agricultural Applications
This paper presents a semi-autonomous seeding robot which is based on both electrical and mechanical platforms that perform advance agriculture process. SeedBot composed of four components: drilling mechanism, body of robot, seed container and paving mechanism. Other than those components the sensor system and the control system are also discussed. The aim of this study is designing and building a low-cost robotic system to automate and optimize process during farming especially for personal usage. This study demonstrates that semi-autonomous farming has crucial advantages over conventional farming. In addition to that, SeedBot provides safer, requires less manpower and precise farming than usual methods that we have so far.