Raman spectroscopy

Review of Stacking Interactions of Nucleobases: NMR Investigations by H. Sapper and W. Lohmann Introduction Nuclear magnetic resonance (NMR) spectroscopy is often a very useful tool to identify organic molecules based on the atomic nuclei interactions with their environment. Recent advances have made use of the technology in protein, nucleic acid, and complex natural products structure identification. [1, 2, 3] Its origins lie in the works of Felix Bloch and Edward Purcell, who used the…

centrifuged and filtered through 0.45 µm filter, diluted suitably and analysed using UV-Visible spectrophotometer (Systronics, India) at λmax of 227nm. All observations were done in triplicate. Fourier Transform Infrared Spectroscopy (FTIR) Fourier Transform Infrared Spectroscopy was performed to characterize and investigate the interaction between levofloxacin and coformers stearic acid and saccharin sodium used. The FTIR spectra for pure levofloxacin, stearic acid, sodium saccharin, L-ST1 and…

5.2 Discussion 5.2.1 Comparison of the results from AFM and optical tweezers experiments 5.2.1.1 Different unfolding behaviors in AFM and optical tweezers experiments In chapter 3, we have studied AFV3-109 using single-molecule AFM. The results from optical tweezers are contradictory to the results from AFM. First, the unfolding force obtained by optical tweezers is much smaller than the force obtained by AFM. More importantly, in our previous study using AFM, the unfolding of AFV3-109 occurs in…

Chapter Three - Conclusions 3.1 Conclusions This research aimed to verify the synthesis protocol for HPA-12 and analogues from aldehydes of Greatrex et al. (2014). Limited success in synthesising required quantities had a negative impact on the outcomes of this research, and no reasons were identified for the low yields that were obtained. Additional time, or resolution of issues resulting in low yields, would have allowed additional research and confirmation of the synthesis protocol. Long…

When EPR spectroscopy is applied, two types of paramagnetic signals have been observed. The low field signal with g = 2.0023 and the other high field signal at g ˜1.96, both are associated with unpaired electrons trapped on oxygen vacancies. It is found that the intensity…

Experiment 5 Synthesis and NMR Spectroscopy of ethyl cinnamate Introduction: Wittig reactions involve the stereoselective synthesis of olefins from phosphonium ylides and aldehydes or ketones, where the carbonyl bond is converted to an alkene double bond.1 The variety of suitable reagents and the relatively mild experimental conditions facilitate their industrial applications, such as the synthesis of epoxides, esters, carotenoids and vitamin A.2,3 Specifically, the ester ethyl cinnamate is used…

In this experiment, a series of reactions was performed in order to synthesize 6-ethoxycarbonyl-3,5-diphenyl-2-cyclohexenone, an a,b-unsaturated ketone. The two reactions performed in order to obtain this product were a Michael addition reaction and an Aldol condensation reaction. During this experiment, the reaction solution underwent several changes. Originally, the initial solution was light yellow and transparent. Once heated, the appearance of the reaction solution became bright yellow.…

resulting in a higher percentage. 2-NBB is less stable than 4-NBB, causing a lower percent yield. IR spectroscopy aids in determining the composition of a compound, allowing for identification. 2-Nitrobromobenzene was shown in product 1, but 4-Nitrobromobenzene could not be tested due to the small amount of product obtained. The two compounds can be distinguished by the peaks on the IR spectroscopy. 4-NBB contains an arene group, while 2-NBB contains an aldehyde/ketone group. The Thin layer…

Kanamycin sulphate and rifampicin were purchased from Hangzhou Dayangchem Co., Ltd., Zhejiang, China. Acetonitrile and ethanol (High performance liquid chromatography, HPLC, grade) were purchased from Merck, Germany. Sodium dihydrogen phosphate, phenylisocyanate, triethylamine, orthophosphoric acid (analytical reagent grade) and silicone oil (viscosity 10 cSt) were purchased from Sigma–Aldrich, St. Louis, USA. Size 3 hard gelatin capsules were kindly donated by Capsugel Co., Ltd., Tokyo, Japan.…

Using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) images and spectra were obtained from various samples of silica and platinum on silica. Each sample contains unique structures which were prepared by etching the surface of silica in different conditions. A scanning electron microscope is a type of electron microscope that produces images of topography and composition by scanning a sample with a focused beam of electrons. Samples can be observed in high vacuum,…