Search results for "Methyl iodide"
showing 10 items of 15 documents
Reinvestigation of the synthesis and evaluation of [N-methyl-11C]vorozole, a radiotracer targeting cytochrome P450 aromatase
2009
Abstract Introduction We reinvestigated the synthesis of [ N -methyl- 11 C]vorozole, a radiotracer for aromatase, and discovered the presence of an N -methyl isomer which was not removed in the original purification method. Herein we report the preparation and positron emission tomography (PET) studies of pure [ N -methyl- 11 C]vorozole. Methods Norvorozole was alkylated with [ 11 C]methyl iodide as previously described and also with unlabeled methyl iodide. A high-performance liquid chromatography (HPLC) method was developed to separate the regioisomers. Nuclear magnetic resonance (NMR) spectroscopy ( 13 C and 2D-nuclear Overhauser effect spectroscopy NMR) was used to identify and assign s…
Die vollständige methylierung phenolischer hydroxylgruppen von struktureinheitlichen mehrkernverbindungen
1965
Die phenolischen Hydroxylgruppen von aus p-Kresol und Formaldehyd hergestellten Mehrkernverbindungen liesen sich nicht mit Methyljodid oder Diazomethan vollstandig methylieren. Wie Loslichkeitsversuche zeigten, sind die untersuchten Mehrkernverbindungen weder als Kryptophenole4,5 noch als behinderte Phenole7 anzusehen; es liegen phenolische Verbindungen mit ausergewohnlichem Reaktionsverhalten vor. Durch Behandeln der Verbindungen in Dioxan mit metallischem Natrium und Dimethylsulfat gelang die Herstellung der Permethylather. Das ist ein weiterer Beweis fur die angegebene Kettenstruktur der Mehrkernverbindungen. Der Versuch, auch halogenhaltige Mehrkernverbindungen an den Hydroxylgruppen au…
Synthesis and some reactions of linear poly(iminohexamethylene)
1987
By complete reduction of polyamide-6, poly(iminohexamethylene) (PIH) was obtained. This new linear polyamine was characterized by i.r. and by n.m.r. spectroscopy as well as by titration. Differential scanning calorimetry measurements and X-ray diffraction found a high degree of crystallinity whose extent strongly depends upon the pre-treatment. The polyammonium salts that form with inorganic and organic acids show the typical polyelectrolyte effect in viscometry. PIH was alkylated with methyl iodide or acrylic acid and was acylated with N-BOC-l-α-amino acids or N-BOC-ω-amino-alkylenecarboxylic acids. The properties of these derivatives are described.
Partialsynthese neuer Ergolinderivate aus Clavinalkaloiden, 3. Mitt.1) O-Acyl- und O-Alkyl-1,6-dimethyl-8-hydroxymethyl-ergol-9-ene
1983
Elymoclavin (1), Lysergol (2) und O-Acyl-lysergole werden in flussigem Ammoniak mit Kalium und Methyliodid zunachst am Indolstickstoff methyliert. Durch Variation der Versuchsbedingungen werden 1 und 2 sekundar auch an der Hydroxylgruppe methyliert. Aus 1-Methyl-lysergol (3) sind daher nach der gleichen Methode mit verschiedenen Alkyliodiden 1-Methyl-lysergol-ether darstellbar. Dagegen gelingt die Ethersynthese nach Williamson aus 17-Halogen-ergolenen nicht. Partial Synthesis of New Ergoline Dervatives from Clavine Alkaloids, III: O-Acyl-and O-Alkyl-1,6-dimethyl-8-(hydroxymethyl)ergol-9-enes Elymoclavine (1), lysergole (2) and O-acyllysergoles are primarily methylated at the indole nitrogen…
Über Chalkogenocarbonate, XLVI. Darstellung und spektroskopische Eigenschaften einiger Dimethyl‐trichalkogenocarbonate
1971
Methyljodid reagiert mit der wasrigen Losung eines leicht loslichen CSe32−-Salzes zu Dimethyltriselenocarbonat und mit der wasrigen Losung eines leicht loslichen CS2Se2−-Salzes zu einem Gemisch aus Dimethyltrithiocarbonat, S.Se-Dimethyl-dithiomonoselenocarbonat und Se.Se′-Dimethyl-monothiodiselenocarbonat. Alle vier Ester bilden in flussiger Phase ein Gemisch aus cis-cis- und cis-trans-Konformeren. On Chalcogenocarbonates, XLVI. Synthesis and Spectroscopic Data of Some Dimethyl Trichalcogenocarbonates By reaction of methyl iodide with an aqueous solution of a readily soluble salt CSe32− dimethyl triselenocarbonate is obtained and by reaction with an aqueous solution of a readily soluble sal…
New Insights into the Stoichiometric and Catalytic Reactivity of Unsaturated Pd 3 (dppm) 3 CO n + Clusters ( n = 0, 1) Towards Halocarbons – First Ev…
2005
The title clusters, Pd 3 (dppm) 3 (CO) + and Pd 3 (dppm) 3 (CO) 0 can be electrochemically generated from the 1- and 2-electron reductions, respectively, of the Pd 3 (dppm) 3 (CO) 2 + cluster [dppm = bis(diphenylphosphanyl)methane; Pd 3 2 + ]. Pd 3 + reacts in a stoichiometric ratio with methyl iodide, MeI, and benzyl bromide, BzBr, in THF to provide the corresponding Pd 3 (X) + adducts (X = I, Br respectively) as inorganic products. Other products are Bz 2 and PhMe for BzBr but, for MeI, no organic product was observed (since they are too volatile). In the presence of the same substrates, Pd 3 0 also reacts in a stoichiometric ratio to form the same organics and the Pd 3 -(X) + adducts (X …
Preparation and Oxidative Addition Reactions of 8-Oxyquinolate Rhodium(I) Complexes
1986
Abstract The preparation of new 8-oxyquinolate rhodium(I) complexes of the general formula Rh(Oq) (L) (L') is described. They undergo oxidative addition reactions with halogens and methyl iodide to give the corresponding rhodium(III) complexes. NMR measurements are used in the characterization of the compounds.
Synthesis of the phytohormone [11C]methyl jasmonate via methylation on a C18 Sep Pak? cartridge
2005
[11C]labeled (±)-methyl jasmonate was synthesized using a C18 Sep Pak™ at ∼100°C to sustain a solid-supported 11C-methylation reaction of sodium (±)-jasmonate using [11C]methyl iodide. After reaction, the Sep Pak was rinsed with acetone to elute the labeled product, and the solvent evaporated rendering [11C]-(±)-methyl jasmonate at 96% radiochemical purity. The substrate, (±)-jasmonic acid, was retained on the Sep Pak so further chromatography was unnecessary. Total synthesis time was 25 min from the end of bombardment (EOB) which included 15 min to generate [11C]methyl iodide using the GE Medical Systems PET Trace MeI system, 5 min for reaction and extraction from the cartridge, and 5 min …
Detection and localisation of disulphide bonds in a synthetic peptide reproducing the sequence 1-30 ofPar j1.0101 by electrospray ionisation mass spe…
2001
The structural characterisation of a synthetic peptide reproducingthe sequence 1–30 of Par j 1.0101, a major allergenic protein present in the pollen of Parietaria judaica, by combined use of chemical and enzymatic cleavage, reversed-phase high-performance liquid chromatography (RP-HPLC) and electrospray ionisation mass spectrometry (ESI-MS), is described. Direct ESI-MS of the synthetic peptide after reaction with methyl iodide showed that the product is a mixture of two peptides: one form in which two out of the four cysteine residues present in the sequence are oxidised and a minor amount of another form in which all the cysteines are fully reduced. It was ascertained, usingthe combined p…
Aminoendgruppenhaltige polymere durch anionische polymerisation von vinylverbindungen mit 3-Dimethylaminopropyllithium als initiator
1975
α-Methylstyrol (in THF) sowie Styrol bzw. Butadien (in Benzol) wurden mit 3-Dimethyl-aminopropyllithium (1) als Initiator homopolymerisiert; dabei wurden aufgrund des Einflusses der tertiaren Aminogruppe bei der Polymerisation in apolarem Medium, verglichen mit der Initiierung durch Butyllithium, Veranderungen der Mikrostruktur der Polymeren beodachtet. Die Molekulargewichte der Polymeren sind hoher, als sich nach dem eingesetzten Monomer/Initiator-Verhatnis berechnete. Der Aminoendgruppengehalt der Polymeren wurde elementaranalytisch sowie NMR-spektroskopisch quantitative bestimmt; die tertiaren Aminoendgruppen konnten mit Methylijodid quantitativ zum quartaren Salz umgesetz werden, mit Br…