Synthesis of 4-Organoselanyl-1H-pyrazoles: Oxone®-Mediated Electrophilic Cyclization of α,β-Alkynyl Hydrazones by Using Diorganyl Diselenides

Synthesis ◽  
2019 ◽  
Vol 51 (11) ◽  
pp. 2293-2304 ◽  
Author(s):  
Gelson Perin ◽  
Patrick Nobre ◽  
Daniela Mailahn ◽  
Márcio Silva ◽  
Thiago Barcellos ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
High Resolution ◽  
High Resolution Mass Spectrometry ◽  
Electrophilic Cyclization ◽  
Diphenyl Diselenide ◽  
Halogen Free ◽  
77Se Nmr Spectroscopy ◽  
Resolution Mass

A simple and efficient method for the synthesis of 4‑organoselanyl-1H-pyrazoles has been developed, taking place under metal- and halogen-free conditions. Electrophilic species of selenium were easily generated in situ by the reaction of diorganyl diselenides with Oxone® in ethanol as solvent in an open-flask at 70 °C. These electrophilic selenium species were employed in the selenylation/cyclization of α,β-alkynyl hydrazones, giving the title compounds in moderate to excellent yields. The final species of selenium obtained from the reaction of diphenyl diselenide with Oxone® were characterized by 77Se NMR spectroscopy and high-resolution mass spectrometry (HRMS).

scholarly journals Ircinal E, a New Manzamine Derivative from the Indonesian Marine Sponge Acanthostrongylophora ingens

2015 ◽  
Vol 10 (11) ◽  
pp. 1934578X1501001 ◽  
Author(s):  
Mousa AlTarabeen ◽  
Georgios Daletos ◽  
Weaam Ebrahim ◽  
Werner E. G. Müller ◽  
Rudolf Hartmann ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
High Resolution ◽  
Cell Line ◽  
Marine Sponge ◽  
High Resolution Mass Spectrometry ◽  
Two Dimensional ◽  
Meoh Extract ◽  
L5178y Cell ◽  
Resolution Mass

Chemical investigation of the MeOH extract of the sponge Acanthostrongylophora ingens afforded the new manzamine derivative ircinal E (1), in addition to six known metabolites (2–7). The structure of the new compound was unequivocally elucidated using one- and two-dimensional NMR spectroscopy, as well as high-resolution mass spectrometry. Compounds 1–6 exhibited strong to moderate cytotoxicity against the murine lymphoma L5178Y cell line with IC50 values ranging from 2.8 to 21.7 μM.

scholarly journals Two New Tropane Alkaloids from the Bark of Erythroxylum vacciniifolium Mart. (Erythroxylaceae)

2009 ◽  
Vol 4 (10) ◽  
pp. 1934578X0900401 ◽  
Author(s):  
Emerson F. Queiroz ◽  
Boris Zanolari ◽  
Andrew Marston ◽  
David Guilet ◽  
Leila Burgener ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
High Resolution ◽  
Traditional Medicine ◽  
High Resolution Mass Spectrometry ◽  
Tropane Alkaloids ◽  
Tropane Alkaloid ◽  
High Resolution Mass ◽  
Indigenous Plant ◽  
Resolution Mass

Two new tropane alkaloid N-oxides substituted by a methylpyrrole moiety were isolated from the bark of Erythroxylum vacciniifolium Mart. (Erythroxylaceae), a Brazilian indigenous plant, locally known as catuaba and used in traditional medicine as an aphrodisiac. The alkaloid structures were determined by a combination of high resolution mass spectrometry and multi-dimensional NMR spectroscopy.

Constitution and HPLC Resolution of Enantiomers of the [8,4'-μ-R2N-commo-(1,2-C2B9H10)2-3-Co] Complexthe Third Isomer of Nitrogen-Bridged Bis

1994 ◽  
Vol 59 (2) ◽  
pp. 374-380 ◽  
Author(s):  
Jaromír Plešek ◽  
Bohumír Grüner ◽  
Stanislav Heřmánek ◽  
Jiří Fusek ◽  
Hana Votavová
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
High Resolution ◽  
Main Product ◽  
High Resolution Mass Spectrometry ◽  
Asymmetric Structure ◽  
Complex Reaction ◽  
Resolution Of Enantiomers ◽  
Cosy Nmr ◽  
Resolution Mass

A fully asymmetric structure of the [4,8'-μ-R2N-commo-(1,2-C2B9H10)2-3-Co] (R = H and Me) cobaltacarborane complexes with a monoatomic nitrogen bridge between both ligands was determined by high resolution mass spectrometry and 1H, 11B NMR, [11B-11B] COSY NMR spectroscopy. Their structures have been also supported by the resolution of both compounds into enantiomers on the β-cyclodextrin HPLC column. A complex reaction of the [3-Co-commo-(1,2-C2B9H11)2]- ion with the NO+ cation is briefly discussed and the tentative structure of the second main product is also suggested.

scholarly journals A New Glucuronolactone Glycoside Phoenixoside B from the Seeds of Phoenix Dactylifera

2013 ◽  
Vol 8 (9) ◽  
pp. 1934578X1300800
Author(s):  
Sumbul Azmat ◽  
Rehana Ifzal ◽  
Faryal Vali Mohammad ◽  
Viqar Uddin Ahmad ◽  
Aqib Zahoor
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
High Resolution ◽  
High Resolution Mass Spectrometry ◽  
Soluble Fraction ◽  
2D Nmr ◽  
Phoenix Dactylifera ◽  
2D Nmr Spectroscopy ◽  
High Resolution Mass ◽  
Resolution Mass

A new glucuronolactone glycoside, phoenixoside B (1), has been isolated from the n-butanol soluble fraction of seeds of Phoenix dactylifera. The structure was characterized as 1-(1-ethyl-β-D-glucosyl)-4,5-diethyl-[α-D-glucofuranourono-6,3-lactone] on the basis of 1D and 2D-NMR spectroscopy and high-resolution mass spectrometry.

Study of the sedge (Cárex) lignin by high-resolution mass spectrometry and NMR spectroscopy

2020 ◽  
Vol 69 (10) ◽  
pp. 2004-2012
Author(s):  
I. I. Pikovskoi ◽  
D. S. Kosyakov ◽  
A. V. Faleva ◽  
I. S. Shavrina ◽  
A. Yu. Kozhevnikov ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
High Resolution ◽  
High Resolution Mass Spectrometry ◽  
High Resolution Mass ◽  
Resolution Mass

A New Sesquiterpene Lactone Sulfate from Reichardia gaditana (Asteraceae)

2007 ◽  
Vol 62 (1) ◽  
pp. 132-134 ◽  
Author(s):  
Christian Zidorn ◽  
Ernst-Peter Ellmerer ◽  
Werner Heller ◽  
Richard Greil ◽  
Manuela Guggenberger ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
High Resolution ◽  
Structure Elucidation ◽  
Methanolic Extract ◽  
High Resolution Mass Spectrometry ◽  
2D Nmr ◽  
2D Nmr Spectroscopy ◽  
Asteraceae Family ◽  
Resolution Mass

The new sesquiterpenoid 8-deoxy-15-(3′-hydroxy-2′-methyl-propanoyl)-lactucin 3′-sulfate (1) was isolated from the methanolic extract of roots of Reichardia gaditana L. The compound was isolated by silica gel column chromatography (CC) and repeated Sephadex LH-20 CC. Structure elucidation was accomplished by high-resolution mass spectrometry and by 1D- and 2D-NMR spectroscopy. The chemosystematic significance of the new compound is discussed in the context of sesquiterpenoids from other members of the Lactuceae tribe of the Asteraceae family.

scholarly journals A New Megastigmane Glycoside, Phoenixoside A, from Phoenix Dactylifera

2012 ◽  
Vol 7 (1) ◽  
pp. 1934578X1200700
Author(s):  
Sumbul Azmat ◽  
Aqib Zahoor ◽  
Rehana Ifzal ◽  
Viqar Uddin Ahmad ◽  
Faryal Vali Mohammed
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
High Resolution ◽  
High Resolution Mass Spectrometry ◽  
Soluble Fraction ◽  
2D Nmr ◽  
Phoenix Dactylifera ◽  
Cd Spectroscopy ◽  
2D Nmr Spectroscopy ◽  
Resolution Mass

A new megastigmane glycoside, phoenixoside A (1), has been isolated from the n-butanol - soluble fraction of seeds of Phoenix dactylifera. The structure was characterized as (6S,7Z,9R)-hydroxy-3-oxo-ionol-9- O-β-D-glucopyranosyl-(1″→6′)-β-D–glucopyranoside on the basis of 1D and 2D NMR spectroscopy, high-resolution mass spectrometry, and CD spectroscopy.

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