Synthesis of metal-free tetraazaisobacteriochlorin and via template condensation of phthalogenes

2020 ◽  
Vol 24 (05n07) ◽  
pp. 878-886
Author(s):  
Semyon V. Dudkin ◽  
Takahiro Kawata ◽  
Svetlana A. Belova ◽  
Yusuke Okada ◽  
Nagao Kobayashi
Keyword(s):  
Mass Spectrometry ◽  
Quantum Chemical ◽  
2D Nmr ◽  
Metal Free ◽  
Tert Butyl ◽  
H Nmr ◽  
Nmr Data ◽  
Template Condensation ◽  
Td Dft ◽  
Low Symmetry

The indium(III) complexes of (4-(tert-butyl)phenyl)-substituted tetraazaisobacteriochlorin (TAiBC) and tetraazachlorin (TAC) were synthesized by direct template condensation of bis(4-(tert-butyl)phenyl)fumaronitrile and tetramethylsuccinonitrile using indium(III) ion as a matrix. The corresponding metal-free tetraazaisobacteriochlorin and tetraazachlorin were obtained by demetallation of their indium(III) complexes. These metal-free complexes were characterized using elemental analysis, mass-spectrometry, 1H and [Formula: see text]C{1H}NMR spectroscopy, UV-vis and MCD spectroscopy as well as DFT and TD-DFT calculations. Due to the low symmetry of the molecules, the NMR data were complex, but could be assigned by collecting 1D- and 2D NMR data and comparing with the results of quantum chemical calculations. From the position of the pyrrole proton signal (6.78 ppm), it was found that the diatropic current of TAiBC is much weaker than that of TAC, and plausibly the weakest among porphyrinoids so far reported. Absorption and MCD spectra were reasonably interpreted using the calculated absorption spectra.

scholarly journals Ambient-Temperature Synthesis of (E)-N-(3-(tert-Butyl)-1-methyl-1H-pyrazol-5-yl)-1-(pyridin-2-yl)methanimine

Molbank ◽  
10.3390/m1250 ◽  
2021 ◽  
Vol 2021 (3) ◽  
pp. M1250
Author(s):  
Diana Becerra ◽  
Justo Cobo ◽  
Juan-Carlos Castillo
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
Ambient Temperature ◽  
Magnesium Sulfate ◽  
Elemental Analysis ◽  
Condensation Reaction ◽  
2D Nmr ◽  
2D Nmr Spectroscopy ◽  
Temperature Synthesis ◽  
Tert Butyl

We report the ambient-temperature synthesis of novel (E)-N-(3-(tert-butyl)-1-methyl-1H-pyrazol-5-yl)-1-(pyridin-2-yl)methanamine 3 in 81% yield by a condensation reaction between 3-(tert-butyl)-1-methyl-1H-pyrazol-5-amine 1 and 2-pyridinecarboxaldehyde 2 in methanol using magnesium sulfate as a drying agent. The N-pyrazolyl imine 3 was full characterized by IR, 1D, and 2D NMR spectroscopy, mass spectrometry, and elemental analysis.

scholarly journals A NEW CYTOTOXIC DOLABELLANE FROM THE INDONESIAN SOFT CORAL Anthelia sp.

2013 ◽  
Vol 13 (3) ◽  
pp. 216-220 ◽  
Author(s):  
Anggia Murni ◽  
Novriyandi Hanif ◽  
Junichi Tanaka
Keyword(s):  
Mass Spectrometry ◽  
Drug Development ◽  
Ethyl Acetate ◽  
Spectroscopic Data ◽  
Soft Coral ◽  
Ethyl Acetate Extract ◽  
2D Nmr ◽  
Cancer Drug ◽  
Nmr Data ◽  
Anti Cancer

One new dolabellane (1) and two known diterpenoids stolonidiol (2) and clavinflol B (3) have been isolated from the ethyl acetate extract of the Indonesian soft coral Anthelia sp. A new compound 1 exhibited a moderate cytotoxicity against NBT-T2 cells at 10 µg/mL, while known compounds 2 and 3 showed cytotoxicity at 1 and 0.5 µg/mL, respectively. Structure of the new compound 1 was elucidated by interpretation of NMR spectroscopic data (1D and 2D NMR data) and mass spectrometry (ESIMS data) as well as comparison with those of related ones. This finding should be useful for anti cancer drug development of the promising dolabellane-types compound.

scholarly journals Spirostane-type Saponins from Dracaena fragrans « Yellow Coast »

2015 ◽  
Vol 10 (1) ◽  
pp. 1934578X1501000
Author(s):  
Abdelmalek Rezgui ◽  
Anne-Claire Mitaine-Offer ◽  
Tomofumi Miyamoto ◽  
Chiaki Tanaka ◽  
Marie-Aleth Lacaille-Dubois
Keyword(s):  
Mass Spectrometry ◽  
2D Nmr ◽  
Steroidal Glycosides ◽  
Nmr Data ◽  
First Time

Three steroidal glycosides were isolated from the bark of Dracaena fragrans (L.) Ker Gawl. « Yellow Coast », and a fourth from the roots and the leaves. Their structures were characterized on the basis of extensive 1D and 2D NMR experiments and mass spectrometry, and by comparison with NMR data of the literature. These saponins have the spirostane-type skeleton and are reported in this species for the first time.

Structural Studies of Chelirubine and Chelilutine Free Bases

1998 ◽  
Vol 63 (7) ◽  
pp. 1045-1055 ◽  
Author(s):  
Jiří Dostál ◽  
Jiří Slavík ◽  
Milan Potáček ◽  
Radek Marek ◽  
Otakar Humpa ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
Quantum Chemical ◽  
2D Nmr ◽  
Molecular Symmetry ◽  
Structural Studies ◽  
Free Base ◽  
2D Nmr Spectroscopy ◽  
Sanguinaria Canadensis ◽  
First Time

The structures of chelirubine and chelilutine free bases have been examined by 2D NMR spectroscopy and mass spectrometry. Chelirubine chloride (1a) upon treatment with Na2CO3 yielded free base which possessed the constitution of bis(5,6-dihydrochelirubin-6-yl) ether (2a). The free base of chelilutine (1b) was determined to be bis(5,6-dihydrochelilutin-6-yl) ether (2b). The aqueous NH3 treatment of chelilutine (1b) produced bis(5,6-dihydrochelilutin-6-yl)amine (3b). 6-Hydroxy-5,6-dihydrochelirubine (4a) and 6-hydroxy-5,6-dihydrochelilutine (4b) were detected only in CDCl3 solution by NMR spectroscopy. In CDCl3, the compound 2b underwent hydrolysis to 4b that was immediately followed by the reverse condensation to a diastereomer of 2b. Pseudokinetics of this reaction was followed by NMR spectroscopy and quantum chemical calculations were carried out to support the suggested type of molecular symmetry alteration. The known alkaloid dihydrochelirubine (5) was isolated for the first time from Sanguinaria canadensis.

scholarly journals Photoisomerisierung von trans-1-(3.5-Di-tert-butyl-4-hydroxyplienyl)-2-phenyldiazen / Photoisomerization of trans-1-(3,5-Di-tert-butyl-4-hydroxyphenyl)-2-phenyldiazene

1980 ◽  
Vol 35 (2) ◽  
pp. 233-236 ◽  
Author(s):  
Edgar Hofer
Keyword(s):  
Nmr Spectroscopy ◽  
Title Compound ◽  
Tautomeric Equilibrium ◽  
Tert Butyl ◽  
H Nmr ◽  
Nmr Data ◽  
Trans Isomerization ◽  
Different Temperatures ◽  
Influence Of Solvent

AbstractLight induced isomerizations of the title compound have been studied. The thermal cis-trans isomerization 3→1 occurs via the tautomeric quinonephenylhydrazone (2) as shown by 1H NMR, spectroscopy. The influence of solvent on the thermal cis-trans isomerization is discussed. 1H NMR data of 1, 2 and 3 are given. Values of the tautomeric equilibrium 1⇋2 are determined for various solvents and different temperatures.

scholarly journals A Deeper Investigation of Drug Degradation Mixtures Using a Combination of MS and NMR Data: Application to Indapamide

Molecules ◽  
2019 ◽  
Vol 24 (9) ◽  
pp. 1764 ◽  
Author(s):  
Cécile Palaric ◽  
Roland Molinié ◽  
Dominique Cailleu ◽  
Jean-Xavier Fontaine ◽  
David Mathiron ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Degradation Products ◽  
Multivariable Analysis ◽  
Active Pharmaceutical Ingredient ◽  
2D Nmr ◽  
Forced Degradation ◽  
Drug Degradation ◽  
Uniform Sampling ◽  
Nmr Data ◽  
Data Application

A global approach that is based on a combination of mass spectrometry (MS) and nuclear magnetic resonance (NMR) data has been developed for a complete and rapid understanding of drug degradation mixtures. We proposed a workflow based on a sample preparation protocol that is compatible to MS and NMR, the selection of the most appropriate experiments for each technique, and the implementation of prediction software and multivariable analysis method for a better interpretation and correlation of MS and NMR spectra. We have demonstrated the efficient quantification of the remaining active pharmaceutical ingredient (API). The unambiguous characterization of degradation products (DPs) was reached while using the potential of ion mobility-mass spectrometry (IM-MS) for fragment ions filtering (HDMSE) and the implementation of two-dimensional (2D) NMR experiments with the non-uniform sampling (NUS) method. We have demonstrated the potential of quantitative NMR (qNMR) for the estimation of low level DPs. Finally, in order to simultaneously monitor multi-samples, the contribution of partial least squares (PLS) regression was evaluated. Our methodology was tested on three indapamide forced degradation conditions (acidic, basic, and oxidative) and it could be easily transposed in the drug development field to assist in the interpretation of complex mixtures (stability studies, impurities profiling, and biotransformation screening).

Anwendungen der 2 D-NMR-Spektroskopie in der Organophosphorchemie Beispiel: L-Menthyldichlorphosphan / Applications of the 2D NMR Spectroscopy in the Organophosphorus Chemistry Example: L-Menthyldichlorophosphine

1982 ◽  
Vol 37 (12) ◽  
pp. 1661-1664 ◽  
Author(s):  
Martin Feigel ◽  
Gerhard Hägele ◽  
Axel Hinke ◽  
Gudrun Tossing
Keyword(s):  
Nmr Spectroscopy ◽  
2D Nmr ◽  
2D Nmr Spectroscopy ◽  
H Nmr ◽  
Nmr Parameters ◽  
Nmr Data ◽  
Organophosphorus Chemistry ◽  
C Nmr

2D NMR ist used to determine the 1H NMR parameters of L-Menthyldichlorophosphine. 13C NMR data are given

Antioxidant activities of the new tetrasubstituted metal-free, Zn(II) and Co(II) monophthalocyanines

2018 ◽  
Vol 22 (01n03) ◽  
pp. 233-242 ◽  
Author(s):  
Nazlı Söylemez ◽  
Ebru Yabaş ◽  
Serap Şahin Bölükbaşı ◽  
Mustafa Sülü
Keyword(s):  
Hydrogen Peroxide ◽  
Hydroxyl Radicals ◽  
Antioxidant Activities ◽  
High Solubility ◽  
Metal Free ◽  
Tert Butyl ◽  
H Nmr ◽  
Aggregation Behaviors ◽  
C Nmr

4-[(4′-(Tert-butyl)phenoxy)phenoxy]phthalonitrile 1 has been prepared by the reaction of 4-(4-nitrophenoxy)phthalonitrile with 4-tertiarylbutylphenole. 4-((4′-tert-butyl)phenoxy)phenoxy tetrasubstituted metal-free 2, zinc(II) 3 and cobalt(II) 4 phthalocyanines have been prepared by tetramerization of compound 1. The synthesized phthalocyanines showed high solubility in common organic solvents such as CHCl[Formula: see text]. All compounds were characterized by elemental analysis and [Formula: see text]H-NMR, [Formula: see text]C-NMR, UV-vis, IR spectra. Aggregation behaviors of these compounds have been investigated in different solvents (CHCl[Formula: see text], THF, DMF and DMSO) and different concentrations in CHCl[Formula: see text]. The in vitro antioxidant activities of phthalocyanine compounds 2, 3 and 4 were evaluated in a series of assays involving DPPH radicals, hydroxyl radicals, superoxide radicals, singlet oxygen and hydrogen peroxide. Antioxidant activity of compound 2was found to be higher than that of compounds 3 and 4.

Gilded Chalices: Tetra-aurated Calix[4]arenes

2014 ◽  
Vol 69 (11-12) ◽  
pp. 1061-1072 ◽  
Author(s):  
Ulf H. Strasser ◽  
Beate Neumann ◽  
Hans-Georg Stammler ◽  
Raphael J. F. Berger ◽  
Norbert W. Mitzela
Keyword(s):  
Crystal Structure ◽  
Mass Spectrometry ◽  
Quantum Chemical ◽  
Molecular Structures ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Elemental Analyses ◽  
One Step ◽  
Energy Of Formation

Abstract 5,11,17,23-Tetrakis(trimethylsilylethynyl)-25,26,27,28-tetra-n-propoxycalix[4]arene (1) was synthesised in two steps starting from 25,26,27,28-tetra-n-propoxycalix[4]arene, and the structure of 1 was determined by X-ray diffraction. Compound 1 was desilylated (K2CO3) to give 5,11,17,23- tetrakis(ethynyl)-25,26,27,28-tetra-n-propoxycalix[4]arene (2), which was tetra-aurated under basic conditions (NaOEt, THF) with a series of phosphane-gold chlorides (o-Tol3PAuCl, Ph3PAuCl, Ph2MePAuCl, PhMe2PAuCl, Me3PAuCl, Cy3PAuCl, t-Bu3PAuCl) to afford in good to excellent yields the tetra-aurated tetraethynylcalix[4]arene species 3-9 in one step [with phosphane ligands o-Tol3P (3), Ph3P (4), Ph2MeP (5), PhMe2P (6), Me3P (7), Cy3P (8), t-Bu3P (9)]. All compounds were characterised by 1H NMR and infrared spectroscopy, mass spectrometry and by elemental analyses, additionally 3, 4, 5, 8 and 9 by 13C{1H}, and 3-6, 8 and 9 by 31P{1H} NMR spectroscopy. The molecular structures of complexes 3 and 9 were determined by X-ray diffraction and show pinched-cone conformations, but neither intra- nor intermolecular attractive aurophilic Au···Au contacts. The acceptor ability of complexes 3 and 9 was investigated by complexation attempts with various phosphane-gold chlorides and xenon gas under pressure, but interactions could not be determined experimentally. The formation of a complex between xenon and gilded calix[4]arene could, however, be predicted for fluorine-substituted species and with very small phosphane ligands (PH3) on the basis of quantum-chemical calculations; the energy of formation is 9:6 kJ mol-1. The crystal structure of Ph2MePAuCl was also determined and shows Au···Au-bonded dimers.

Structure of a pentacyclic triterpenyl angelate from Loeseliamexicana. 1H 2D-NMR data and stereochemistry

1989 ◽  
Vol 67 (12) ◽  
pp. 2071-2077 ◽  
Author(s):  
M. Jiménez E. ◽  
K. Velézquez ◽  
A. Lira-Rocha ◽  
A. Ortega ◽  
E. Díaz ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Parent Compound ◽  
2D Nmr ◽  
X Ray Diffraction ◽  
Pentacyclic Triterpene ◽  
Nmr Structure Determination ◽  
X Ray ◽  
H Nmr ◽  
Nmr Data ◽  
Unambiguous Assignment

The total assignment of 1H NMR spectra of a pentacyclic triterpene from Loeseliamexicana was performed using selected 2D-NMR experiments (COSY, NOE). X-ray diffraction data were obtained from the parent compound as supplemental information to the NMR investigations. The data allowed for the unambiguous assignment of the structure and the stereochemistry of the title compound. Keywords: pentacyclic triterpene NMR, 2D NMR of terpenes, X-ray of triterpenes, triterpenyl angelate NMR, X-ray -2D NMR structure determination.

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