Synthesis, separation, and identification of 4-bromoadamantan-2-one stereoisomers

1980 ◽  
Vol 45 (10) ◽  
pp. 2670-2674 ◽  
Author(s):  
Luděk Vodička ◽  
Jan Tříska ◽  
Milan Hájek
Keyword(s):  
Ir Spectra ◽  
Hydrobromic Acid ◽  
Mass Spectra ◽  
Nmr Spectra ◽  
Dipole Moments ◽  
Hydroxylamine Hydrochloride ◽  
Shift Reagent ◽  
One Step ◽  
Elution Chromatography ◽  
The Eu

A one-step synthesis of mixture of stereoisomers of 4-bromoadamantan-2-one based on the reaction of adamantan-2-one with hydroxylamine hydrochloride in hydrobromic acid is described. The pure stereoisomers were isolated by elution chromatography on silica gel, and their NMR spectra with the Eu(FOD)3 shift reagent, mass spectra, IR spectra, and dipole moments were measured.

Beckmann rearrangement of adamantanone oxime as a route to ditopic and tritopic secondarily substituted adamantane derivatives

1984 ◽  
Vol 49 (8) ◽  
pp. 1774-1779 ◽  
Author(s):  
Jan Tříska ◽  
Luděk Vodička ◽  
Eugenijus P. Butkus ◽  
Milan Hájek
Keyword(s):  
Silica Gel ◽  
Hydrobromic Acid ◽  
Nmr Spectra ◽  
Hydroxylamine Hydrochloride ◽  
Beckmann Rearrangement ◽  
Adsorption Chromatography ◽  
Adamantane Derivatives ◽  
Acid Solutions ◽  
Hydroiodic Acid ◽  
Pure Substances

The reaction in mixtures of adamantanone with hydroxylamine hydrochloride was studied in hydrochloric, hydrobromic, and hydroiodic acid solutions. In hydrochloric and hydroiodic acids, mixtures of isomers of 4-chloroadamantan-2-one and 4-iodoadamantan-2-one, respectively, are formed, whereas in hydrobromic acid in the presence of excess hydroxylamine hydrochloride, three stereoisomers of 4,8-dibromoadamantan-2-one appear. All the stereoisomeric haloketones were isolated by elution adsorption chromatography on silica gel or by crystalization. For the pure substances, their infrared, mass, and NMR spectra were measured.

Structure Revision of Protoaculeine B, a Posttranslationally Modified N-Terminal Residue in the Peptide Toxin Aculeine B

2020 ◽  
Author(s):  
Raku Irie ◽  
Kei Miyako ◽  
Satoko Matsunaga ◽  
Ryuichi Sakai ◽  
Masato Oikawa
Keyword(s):  
Mass Spectra ◽  
Chemical Reactivity ◽  
Model Compounds ◽  
Structural Revision ◽  
Structure Revision ◽  
Peptide Toxin ◽  
One Step ◽  
Marine Peptide ◽  
Synthetic Models ◽  
Long Chain

<div>Here, we newly propose the structure of protoaculeine B, an N-terminal moiety of the marine peptide toxin aculeine B, as possessing the cis-disubstituted tetrahydro-beta-carboline framework. We prepared two truncated model compounds that lack long-chain polyamine by one-step Pictet-Spengler reaction of tryptophan, and compared the NMR and mass spectra and chemical reactivity with those of natural protoaculeine B. The synthetic models reproduced the profiles of the natural product well, which was conclusive for the structural revision.</div>

scholarly journals Isocyanate und verwandte Verbindungen des trimeren Phosphornitriddifluorids / Isocyanates and Related Compounds of Trimeric Phosphor-difluoronitride

1971 ◽  
Vol 26 (7) ◽  
pp. 679-683 ◽  
Author(s):  
Herbert W. Roesky ◽  
Enno Janssen
Keyword(s):  
Ir Spectra ◽  
Elemental Analysis ◽  
Mass Spectra ◽  
H Nmr ◽  
Carbonic Acids ◽  
Related Compounds

P3N3F5NCO was prepared by reaction of P3N3F5NSO with (COCl) 2. Substituted amides were obtained from the reaction of P3N3F5NSO with carbonic acids e. g. P3N3F5NHCOCH3, P3N3F5NHCOC2H5, and P3N3F5NHCOC3H7. If these substances were treated with PCl5 the following compounds P3N3F5N = CClCH3, P3N3F5N = CClCH5, and P3N3F5TN = CClC3H7 were formed. They reacted with nucleophiles to give P3N3F5N = CNH2CH3, P3N3F5N = TN (CH3) 2C2H5, and P3N3F5N = CN (CH3) 2CH7. The properties of these compounds are described. They were characterized by elemental analysis and IR-spectra. 19F-, 1H-NMR, and mass spectra are reported.

Synthesis and structure of 2?-substituted 1-(1,3-dioxan-5-yl)uracils. Positive role of the Eu(fod)3 nmr shift reagent

1981 ◽  
Vol 17 (11) ◽  
pp. 1112-1119
Author(s):  
Yu. Yu. Samitov ◽  
I. N. Goncharova ◽  
N. P. Ramzaeva ◽  
A. F. Mishnev ◽  
Ya. Ya. Bleidelis
Keyword(s):  
Shift Reagent ◽  
Positive Role ◽  
Substituted 1 ◽  
The Eu

scholarly journals Metallkomplexe mit Tetrapyrrol-Liganden, XXXVIII [1]. Zur Kenntnis der Alkyl- und Arylimidovanadium(IV)-Porphyrine / Metal Complexes with Tetrapyrrole Ligands, XXXVIII [1]. On the Knowledge of Alkyl- and Arylimidovanadium(IV) Porphyrins

1985 ◽  
Vol 40 (10) ◽  
pp. 1362-1370 ◽  
Author(s):  
Johann W. Buchler ◽  
Stefan Pfeifer
Keyword(s):  
Mass Spectra ◽  
Nmr Spectra ◽  
Primary Amines ◽  
Reactive Intermediate ◽  
H Nmr ◽  
Vanadyl Complex ◽  
Elemental Analyses ◽  
Paramagnetic Metal ◽  
Paramagnetic Complexes ◽  
Proton Resonances

A series of novel alkyl or aryiimidovanadium(IV) 5,10,15,20-tetra(p-tolyl)porphyrinates, VNR(TTP) (4a-4g), is described. They are obtained from the vanadyl complex, VO(TTP) (2a) via the reactive intermediate VCl2(TTP) (3b) which undergoes aminolysis with the respective primary amines RNH2 (R = tBu, Ph, pTol, pClPh, pAnis, pBiph, ptBuPh)**. The formulae are proved by elemental analyses and mass spectra. The paramagnetic complexes are stable to water and may thus be purified by chromatography but are hydrolyzed to give 2 a on treatment with acetic acid. The UV/VIS and 1H NMR spectra of 4a-4g are of the same type as 2a, but the former are slightly hypsochromically shifted, and the latter do not show the proton resonances of the organylimide ligands due to the proximity of the paramagnetic metal center.

scholarly journals New Perfluorophtalate Complexes of Platinum(II) With Chemotherapeutic Potential

1996 ◽  
Vol 3 (3) ◽  
pp. 117-122
Author(s):  
M. B. de Oliveira ◽  
J. Miller ◽  
R. E. Banks ◽  
L. R. Kelland ◽  
C. A. McAuliffe ◽  
...  
Keyword(s):  
Ir Spectra ◽  
Ovarian Carcinoma ◽  
Elemental Analysis ◽  
Nmr Spectra ◽  
Carcinoma Cell ◽  
Acquired Resistance ◽  
Cross Resistance ◽  
Carcinoma Cell Lines ◽  
Human Ovarian Carcinoma ◽  
Anti Hiv

Two new platinum(II) complexes have been synthesized and their anti-tumour and anti-HIV activities have been evaluated.The new complexes are: (i) cis-tetrafluorophthalate-ammine-morpholine-platinum(II) or MMF3 and (ii) cis-tetrafluorophthalate- ammine-piperidine-platinum(II) or MPF4. They were characterized by elemental analysis, IR spectra and H1 and C13 NMR spectra.They were tested against five human ovarian carcinoma cell lines, viz., CH1, CH1cisR, A2780, A2780cisR and SKOV-3. They were less active than cis-platin and showed cross-resistance with cis-platin in the CH1cisR and A2780cisR acquired resistance lines.They were also tested for possible anti-HIV activity using the HIV-I IIIB virus and C8166 cells, but they were inactive compared with AZT.

scholarly journals Salaramides A and B; Two α-Oxoamides Isolated from the Marine Sponge Hippospongia sp. (Porifera, Dictyoceratida)

2010 ◽  
Vol 5 (2) ◽  
pp. 1934578X1000500
Author(s):  
Julia Bensemhoun ◽  
Amira Rudi ◽  
Yoel Kashman ◽  
Emile M. Gaydou ◽  
Jean Vacelet ◽  
...  
Keyword(s):  
Chemical Transformation ◽  
Marine Sponge ◽  
Mass Spectra ◽  
Nmr Spectra ◽  
2D Nmr ◽  
2D Nmr Spectra

Two novel α-oxoamides, salaramide A (1) and its homologue salaramide B (2), were isolated from the Madagascar marine sponge, Hippospongia sp., collected in Salary Bay, north of Tulear. The structures of 1 and 2 were elucidated by interpretation of mass spectra, 1D and 2D NMR spectra, and confirmed by chemical transformation.

Virtual worlds and language learning

2019 ◽  
Vol 11 (1) ◽  
pp. 29-43 ◽  
Author(s):  
Sabela Melchor-Couto
Keyword(s):  
Foreign Language ◽  
Language Learning ◽  
Teacher Perceptions ◽  
Virtual Worlds ◽  
Computer Mediated Communication ◽  
Mediated Communication ◽  
Computer Mediated ◽  
Affective Variables ◽  
One Step ◽  
The Eu

Technology has made an invaluable contribution to foreign language (FL) teaching, particularly so in recent years. The advanced technical capabilities offered by digital games, including voice and text chat, take the use of computer-mediated communication in language learning one step further, allowing for remote, anonymous and situated learner interaction. This article presents an overview on how virtual worlds (VWs) are being used for educational purposes and for FL teaching in particular. A literature review on existing research has been included, covering areas such as FL interaction, impact on affective variables and attitudes towards the use of these environments. Special attention will be devoted to how VW interaction may affect students’ anxiety, motivation and self-efficacy beliefs. Finally, teacher perceptions will be explored through the data collected among 179 secondary school FL teachers participating in the EU-funded TeCoLa project (‘Pedagogical differentiation through telecollaboration and gaming for intercultural and content integrated language teaching’).

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