Nmr spectrum

These mononuclear Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) complexes of the ligand were prepared and their structures were proposed by elemental analysis, and infrared and ultraviolet-visible spectroscopy; the proton NMR spectrum of the mbH ligand was also recorded. The azo-azomethine ligand, mbH, behaves as a bidentate ligand coordinating through the nitrogen atom of the azomethine (–CH=N–) and the oxygen atom of the phenolic group. Elemental analyses indicated that the metal:ligand ratio was 1:2 in the metal chelates.

20p langthannam 29-12-2021 7 0   Download

Metal-free phthalocyanine 3 and its metallophthalocyanine derivatives 4, 5, and 6 (M = Zn, Co, and Ni) substituted with four 21-membered pentathiadiaza macrocycles were synthesized and their structures identified by elemental analysis, IR, 1 H NMR, mass, and UV-Vis spectroscopy techniques. The aggregation properties of phthalocyanines 4, 5, and 6 were investigated in different solvents and at different concentrations of dimethylformamide.

10p langthannam 29-12-2021 5 0   Download

Marine compound dendrodoine was first obtained from tunicate species (Dendrodo grossularia). It has a five-membered ring, namely, it is a heterocycle thiadiazole, which is found rarely in natural sources. Following its biological activities, novel analogs have been investigated recently. Synthesis of the analogs for this study is realized with uncommon thiazole closure, including methylene-carbonyl condensation. Structures are elucidated by NMR (1H, 13C) and HRMS spectrums.

9p tudichquannguyet 29-11-2021 9 1   Download

Five secondary metabolites including three flavonoids, 6-lavandulyl-5,7,2′,4′-tetrahydroxyflavanone (1), 5′- lavandulyl-2′-methoxy-2,4,4′,6′-tetrahydroxychalcone (2), 6-lavandulyl-7-methoxy-5,2′,4′-trihydroxyflavanone (3), and two alkaloids, tryptoline (4), and norharman (5) were isolated from the culture broth of Streptomyces sp. C011. Their structures were determined by spectral data analysis, including MS, 2D NMR, and CD spectrum. All the separated compounds were evaluated for their antimicrobial activities. Compounds 1, 2, 3 and 5 exhibited antimicrobial activity...

5p cothumenhmong11 06-05-2021 13 2   Download

The purpose of study is extraction and isolation of hippadine from the bulbs of Crinum latifolium for using as a reference standard for quality control of herbs and hippadine-containing preparations. Bulbs powder of Crinum latifolium was percolated with 70% ethanol, percolate obtained was evaporated at 65 0C to give a liquid extract. The extract was fractionated by distribution with n-hexane. The n-hexane extract was then chromatographed on silicagel 60 (0.04 - 0.063 mm). Hippadine was isolated, purified and elucidated by NMR, MS, IR and UV-Vis spectrum.

7p trinhthamhodang9 10-12-2020 13 1   Download

Simple peak-picking algorithms, such as those based on lineshape fitting, perform well when peaks are completely resolved in multidimensional NMR spectra, but often produce wrong intensities and frequencies for overlapping peak clusters.

7p vikentucky2711 26-11-2020 11 1   Download

In metabolomics experiments, spectral fingerprints of metabolites with no known structural identity are detected routinely. Computer-assisted structure elucidation (CASE) has been used to determine the structural identities of unknown compounds. It is generally accepted that a single 1D NMR spectrum or mass spectrum is usually not sufficient to establish the identity of a hitherto unknown compound.

9p vikentucky2711 26-11-2020 8 1   Download

Radix Glycyrrhizae is the rhizome of Glycyrrhiza inflata Bat., Glycyrrhiza uralensis Fisch. or Glycyrrhiza glabra L. The present paper describes the isolation and the structural elucidation of three new dihydroisocoumarins obtained from the 70% EtOH extract of Radix Glycyrrhizae.

6p vijiraiya2711 27-05-2020 14 1   Download

In this research, a novel organic photocatalyst of 10-(perylene-3-yl-10H-phenoxazine (PHP) has been successfully synthesized from perylene and phenoxazine via Buchwald-Hartwig C-N coupling. The chemical structure of catalyst was determined via FT-IR, proton nuclear magnetic resonance (1 H-NMR) spectrum and optical properties were investigated through UV-Vis spectroscopy. The PHP has been used as the reducing photoredox catalyst for organocatalyzed atom transfer radical polymerrization (O-ATRP) under UV irradiation.

5p 12120609 02-04-2020 37 3   Download

In this research, the new fluorescent conjugated polymers based on 10-(Perylene-3-yl-10HPhenoxazine (PyP) and 9,9-dioctyl-9h-fluorene (PF) have been synthesized via direct arylation polymerization using Pd(OAc)2, PivOH and PCy3.HBF4 as catalyst system. The monomer based on phenothiazine has been synthesized via C-N coupling to obtain the 4-(10H-phenothiazine-10-yl)- N,N-diphenylaniline (PyP). The synthesized novel conjugated polymers based on PyP and PF have been characterized via 1 H NMR, GPC, FTIR, DSC, XRD, PL, and UV-Vis spectrum.

10p 035522894 26-03-2020 49 2   Download

The thiosemicarbazone of N- (tetra-O-acetyl-β-D-glycopyranosyl) of some naturally derived aldehydes and ketones has been synthesized and studied in the MNMR spectrum. The 1H and 13C NMR spectra of these thiosemicarbazon were discussed. Magnetic resonance signals in their NMR spectrum indicate the relationship between the structure and the position of the resonant signal. The configuration β of these thiosemicarbazon is confirmed based on the pairing constant J = 9.5–8.5 Hz between the NH-4 proton of the thiosemicarbazon proton and the H-1 proton in the sugar component.

7p khidoichuoi 04-03-2020 15 1   Download

Kappaphycus alvarezii is a type of seaweed containing numerous carbohydrates with biological activities, especially fucoidans. In terms of chemical aspect, fucoidansare fucose polysaccharides (FCSPs) with diverse biological activities including antioxidant, anticoagulant, anti-inflammatory, antiviral, antitumor. Fucoidan is found not only in brown algae, but also in K. alvarezii alga from the central coast of Viet Nam. In this study, fucoidan from K.

10p chauchaungayxua2 07-01-2020 26 0   Download

The sodium alginate was prepared from brown seaweeds in Thua-Thien-Hue coastal area. The obtained alginate was characterized by 1 H-NMR, 1 H-1 H TOCSY and COSY spectra. The assignment of alginate peaks in 1 H-NMR spectrum is 5.09, 4.446, 4.152, 4.318, 4.135 ppm in correspondence to H1, H2, H3, H4, H5 of D-mannuronic acid and 5.473, 4.318, 4.446, 4.571, 4.883 ppm in correspondence to H1, H2, H3, H4, H5 of L-guluronic acid, respectively. The present results are essential for the investigating guidance of alginate and its derivatives.

4p chikychiky 11-11-2018 11 0   Download

Six new benzopyran derivatives were synthesized by reduction reaction and Michael reaction from malloapelta B.

5p chikychiky 11-11-2018 37 0   Download

Chapter 13 - Nuclear magnetic resonance spectroscopy. In this chapter, students will be able to understand: Use the chemical shifts, splitting patterns, and integrations shown in a proton NMR spectrum to propose structures for possible compounds; use the number of peaks and their chemical shifts in a 13C NMR spectrum to determine the number of types of carbon atoms in the compound and what functional groups they might represent;...

71p tangtuy02 11-03-2016 51 3   Download

Six new benzopyran derivatives were synthesized by reduction reaction and Michael reaction from malloapelta B.

5p uocvong04 24-09-2015 43 2   Download

Three terpenes with Protostane type were isolated from the rhizomes of Alisma plantago- aquatica. The chemical structures of isolated compounds were characterized as 11 ,23S,24R,25- tetrahydroxyprotost-13(17)-en-3-one (alisol A, 1), 11 ,23S,25-trihydroxyprotost-13(17)-en-3- one-24R-yl acetate (alisol A acetate, 2), and 11 ,23S,24S-trihydroxyprotost-13(17),25-dien-3-one (alisol G, 3), by detailed analysis of the 1D- and 2D-NMR spectra such as 1 H-, 13 C-NMR, DEPT 90, DEPT135, HSQC, HMBC, 1 H- 1 H COSY, and by the Electronspray Ionization (ESI) mass spectrum.

6p uocvong04 24-09-2015 63 3   Download

Chitosan oligomers were prepared by oxidative degradation of chitosan (with hydrogen peroxide) under microwave irradiation. This is convenient, friendly and effective method to prepare chitosan oligomers. By 1 H-NMR, IR spectrum, the structure of the products was identified and keeps the same as of chitosan. By LC-MS analysis, it proved that chitosan was decomposed to five fractions, the smallest one about D- glucosamine 3 units (at least).

5p uocvong02 24-09-2015 48 4   Download

d-Aminolevulinic acid (ALA), which is an intermediate in the biosynthesis of chlorophyll a, can be biosynthesized via theC5pathway and the Sheminpathway inEuglena gracilis. Analysis of the 13 C-NMR spectrum of 13 C-labeled methyl pheophorbidea, derived from 13 C-labeled chlorophylla biosynthesized fromD-[1-13 C]glucose byE. gracilis,provid-ed evidence suggesting that ALA incorporated in the 13 C-labeled chlorophyllawas synthesized via both the C5 pathway and the Shemin pathway in a ratio of between 1.5 and 1.7 to one....

7p research12 29-04-2013 26 2   Download

The NMR solution structures of NTX-1 (PDB code 1W6B and BMRB 6288), a long neurotoxin isolated from the venom ofNaja naja oxiana, and the molecular dynamics simulation of these structures are reported. Calculations are based on 1114NOEs, 19 hydrogen bonds, 19 dihedral angle restraints and secondary chemical shifts derived from 1 Hto 13 C HSQC spectrum. Similar to other long neurotoxins, the three-finger like structure shows a double and a triple strandedb-sheet aswell as some flexible regions, particularly at the tip of loop II and the C-terminal tail....

0p awards 05-04-2013 45 1   Download