Search results for "Nuclear Magnetic Resonance Spectroscopy"

First synthesis of single-“strapped cyclam-porphyrins”

1994

The first synthesis of strapped cyclam porphyrins is described ; these will be studied as dioxygen carriers as well as cytochrome C oxidase models. The original derivatives are characterized by mass spectrometry and 1H NMR spectroscopy. The cofacial conformation of the two different macrocycles is confirmed by 1H NMR data.

Magnetic Resonance Spectrobiopsy for Prediction of Isocitrate Dehydrogenase Mutation in Glioma

2020

Despite the existence of multimodal therapy paradigm, high-grade gliomas (HGGs) remain devastating tumors associated with one of the worst prognoses. Glioblastoma (GBM) is the most frequent reported histologic type with a median survival, after surgery and combined treatment with chemotherapy and radiotherapy, ranging from 12 to 16 months. The poor prognosis is due to the lack of therapeutic efficacy of chemical agents and irradiation in hypoxic tumor areas. Experimental studies have investigated several molecules with the aim to counteract several downstream signaling important in tumor progression, unfortunately without conclusive results. Several studies have shown that the extent of res…

Tuning the photophysical properties of cationic iridium(iii) complexes containing cyclometallated 1-(2,4-difluorophenyl)-1H-pyrazole through function…

2012

Four new heteroleptic iridium(III) complexes in the family [Ir(dfppz)(2)((NN)-N-boolean AND)](+), where Hdfppz = 1-(2,4-difluorophenyl)-1H-pyrazole and (NN)-N-boolean AND = 6-phenyl-2,2'-bipyridine (1), 4,4'-(di-tert-butyl)-6-phenyl-2,2'-bipyridine (2), 4,4'-(di-tert-butyl)-6,6'-diphenyl-2,2'-bipyridine (3) and 4,4'-bis(dimethylamino)-2,2'-bipyridine (4), have been synthesized as the hexafluoridophosphate salts and fully characterized. Single crystal structures of ligand 3 and the precursor [Ir-2(dfppz)(4)(mu-Cl)(2)] have been determined, along with the structures of the complexes 4{[Ir(dfppz)(2)(1)][PF6]}center dot 3CH(2)Cl(2), [Ir(dfppz)(2)(3)][PF6]center dot CH2Cl2 and [Ir(dfppz)(2)(4)][…

Crystallographic, spectroscopic and electrochemical characterization of pyridine adducts of magnesium(II) and zinc(II) porphine complexes

2013

Abstract A new purification method of magnesium(II) and zinc(II) porphine complexes (MgP and ZnP, respectively) by crystallization of their respective pyridine adducts is described. Pure MgP and ZnP can be regenerated by removal of the coordinated pyridine ligands by heating at 200 °C under vacuum. X-ray crystallographic structures of the pyridine adducts are presented for the first time. NMR analyses of the adducts reveal the coordination of two pyridine molecules. Electrochemical as well as UV-vis absorption spectroscopy analyses in DMF of MgP·(Py)2, ZnP·(Py)2, MgP and ZnP indicate that pyridine adducts are totally dissociated. Besides, oxidation peaks of these complexes are totally irrev…

Zur protonenkatalysierten Aralkylierung von 1,2,3-Trimethylindol und 1,2,3,4-Tetrahydrocarbazol mit Arylaldehyden

1987

1,2,3-Trimethylindol (2) liefert mit Benzaldehyden die Kondensationsprodukte 5 und 6, wahrend aus den NH-Indolen 1 und 3 die Verbindungen 7 und 8 entstehen. Proton-catalyzed Aralkylation of 1,2,3-Trimethylindole and 1,2,3,4-Tetrahydrocarbazole with Arylaldehydes Reaction of 1,2,3-trimethylindole (2) with benzaldehydes leads to the condensation compounds 5 and 6, the NH-indoles 1 and 3, however, give 7 and 8.

Characterization of sulfobetaine monomers by nuclear magnetic resonance spectroscopy: a note

1995

A set of zwitterionic monomers bearing the 3-ammoniopropanesulfonate moiety is analysed in CDCl3, CD3OD and D2O by one- and two-dimensional H-1 n.m.r. and C-13 n.m.r. spectroscopy. Absolute and relative positions of the n.m.r, signals are determined depending on the solvent used; the refined assignments of the signals in the vicinity of the ammonium group deviate from previously proposed assignments based on standard n.m.r, shift tables. Still, there is no convincing evidence for a special ring current effect due to a six-membered ring conformation of the betaine moiety.

ChemInform Abstract: High-Resolution Solid-State NMR Spectroscopy of Steroids and Their Derivatives

2013

Abstract: Steroids are an important class of organic compounds containing a vast array of biologically and physiologically essential molecules. Due to their availability, relatively straightforward derivatizability, and endogeneity, they are widely used in pharmacological applications. The investigation of molecular and physicochemical properties of active pharmaceutical ingredients (APIs) in the solid state is important, because these properties are directly related to their pharmacological activity. Several methods are available for this purpose. Solid-state NMR spectroscopy offers a nondestructive and flexible technique, providing both structural and dynamic information. It can be applie…

High-Resolution Solid-State NMR Spectroscopy of Steroids and Their Derivatives

2013

Abstract: Steroids are an important class of organic compounds containing a vast array of biologically and physiologically essential molecules. Due to their availability, relatively straightforward derivatizability, and endogeneity, they are widely used in pharmacological applications. The investigation of molecular and physicochemical properties of active pharmaceutical ingredients (APIs) in the solid state is important, because these properties are directly related to their pharmacological activity. Several methods are available for this purpose. Solid-state NMR spectroscopy offers a nondestructive and flexible technique, providing both structural and dynamic information. It can be applie…

Analgetische Wirkstoffe, 11. Mitt. Diacylderivate des Butyroguanamins

1986

Reaktionen von elektronenreichen Heterocyclen mit Orthocarbonsäure-Derivaten, 9. Acylierungsreaktionen von Indol und Methylindolen mit Dialkoxycarben…

1986

Indol und einige Methylderivate 1 lassen sich unter milden Bedingungen mit den Dialkoxycarbenium-tetrafluoroboraten 2 in meist guten Ausbeuten regioselektive acylieren. Mit dem Formylkation-Aquivalent 2a′ werden mit uberschussigem 1 auch die Bisindolycarbenium-tetrafluoroborate 13a – d erhalten. Reactions of Electron-rich Heterocycles with Orthocarboxylic Acid Derivatives, 9. – Acylation of Indole and Methylindoles with Dialkoxycarbenium Tetrafluoroborates Indole and some methylindoles 1 were acylated regioselectively with dialkoxycarbenium tetrafluoroborates 2 under mild conditions. The formyl cation equivalent 2a′ reacts with excess of indoles 1 to give the bisindolylcarbenium tetrafluoro…