scholarly journals Novel β-cyclodextrin–eosin conjugates

2017 ◽  
Vol 13 ◽  
pp. 543-551 ◽  
Author(s):  
Gábor Benkovics ◽  
Damien Afonso ◽  
András Darcsi ◽  
Szabolcs Béni ◽  
Sabrina Conoci ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Aqueous Medium ◽  
2D Nmr ◽  
Eosin Y ◽  
Synthetic Route ◽  
2D Nmr Spectroscopy ◽  
Reaction Conditions ◽  
Amide Linkage ◽  
Eosin B ◽  
Light Excitation

Eosin B (EoB) and eosin Y (EoY), two xanthene dye derivatives with photosensitizing ability were prepared in high purity through an improved synthetic route. The dyes were grafted to a 6-monoamino-β-cyclodextrin scaffold under mild reaction conditions through a stable amide linkage using the coupling agent 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride. The molecular conjugates, well soluble in aqueous medium, were extensively characterized by 1D and 2D NMR spectroscopy and mass spectrometry. Preliminary spectroscopic investigations showed that the β-cyclodextrin–EoY conjugate retains both the fluorescence properties and the capability to photogenerate singlet oxygen of the unbound chromophore. In contrast, the corresponding β-cyclodextrin–EoB conjugate did not show either relevant emission or photosensitizing activity probably due to aggregation in aqueous medium, which precludes any response to light excitation.

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 Exploring the Phytochemicals of Acacia melanoxylon R. Br.

Plants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2698
Author(s):  
Diana Alves ◽  
Sidónio Duarte ◽  
Pedro Arsénio ◽  
Joana Gonçalves ◽  
Cecília M. P. Rodrigues ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Mass Spectrometry ◽  
Methyl Ester ◽  
Nmr Assignments ◽  
2D Nmr ◽  
Human Colorectal Cancer ◽  
2D Nmr Spectroscopy ◽  
Acacia Melanoxylon ◽  
Colorectal Cancer Cells ◽  
Human Colorectal Cancer Cells

Invasive species are currently a world menace to the environment, although the study of their chemistry may provide a means for their future beneficial use. From a study of Portuguese Acacia melanoxylon R. Br. five known compounds were isolated: lupeol, 3β-Z-coumaroyl lupeol, 3β-E-coumaroyl lupeol (dioslupecin A), kolavic acid 15-methyl ester and vomifoliol (blumenol A). Their structures were elucidated by 1D and 2D NMR spectroscopy and mass spectrometry, and as a result some corrections are made to their previous 13C NMR assignments. Cytotoxicity of 3β-E-coumaroyl lupeol (dioslupecin A) and kolavic acid 15-methyl ester was evaluated against HCT116 human colorectal cancer cells although biological activity was not evident.

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 2-Oxo-2H-chromen-7-yl 4-chlorobenzoate

Molbank ◽  
10.3390/m1279 ◽  
2021 ◽  
Vol 2021 (3) ◽  
pp. M1279
Author(s):  
Diana Becerra ◽  
Jaime Portilla ◽  
Juan-Carlos Castillo
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
2D Nmr ◽  
Acylation Reaction ◽  
2D Nmr Spectroscopy ◽  
Slight Excess

We describe the synthesis of 2-oxo-2H-chromen-7-yl 4-chlorobenzoate 3 in 88% yield by the O-acylation reaction of 7-hydroxy-2H-chromen-2-one 1 with 4-chlorobenzoyl chloride 2 in dichloromethane using a slight excess of triethylamine at 20 °C for 1 h. The ester 3 was completely characterized by mass spectrometry, IR, UV–Vis, 1D, and 2D NMR spectroscopy.

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.

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 Monoterpenoid Oxindole Alkaloid from Hamelia Patens Micropropagated Plantlets

2012 ◽  
Vol 7 (11) ◽  
pp. 1934578X1200701 ◽  
Author(s):  
David Paniagua-Vega ◽  
Carlos M. Cerda-García-Rojas ◽  
Teresa Ponce-Noyola ◽  
Ana C. Ramos-Valdivia
Keyword(s):  
Mass Spectrometry ◽  
Molecular Modeling ◽  
Nmr Spectroscopy ◽  
2D Nmr ◽  
2D Nmr Spectroscopy ◽  
Chemical Studies

Chemical studies on Hamelia patens (Rubiaceae) micropropagated plantlets allowed production of a new monoterpenoid oxindole alkaloid, named (–)-hameline (7), together with eight known alkaloids, tetrahydroalstonine (1), aricine (2), pteropodine (3), isopteropodine (4), uncarine F (5), speciophylline (6), palmirine (8), and rumberine (9). The structure of the new alkaloid was assigned on the basis of 1D and 2D NMR spectroscopy, mass spectrometry, and molecular modeling.

A New Eudesmane Derivative from Leontodon tuberosus

2004 ◽  
Vol 59 (1) ◽  
pp. 95-99 ◽  
Author(s):  
Renate Spitaler ◽  
Ernst-P. Ellmerer ◽  
Christian Zidorn ◽  
Hermann Stuppner
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
Phenolic Acids ◽  
Methanolic Extract ◽  
2D Nmr ◽  
The Novel ◽  
2D Nmr Spectroscopy

Abstract Besides the known compounds 2,4,6-trihydroxyacetophenone 4-O-β -D-glucopyranoside and syringaresinol 4’-O-β -D-glucopyranoside, the novel sesquiterpenoid 1,2-dehydro-3-oxocostic acid β - D-glucopyranoside ester was isolated from Leontodon tuberosus L. and its structure established by mass spectrometry and 1D- and 2D-NMR spectroscopy. Additionally, a number of fatty and phenolic acids was identified in the crude methanolic extract by HPLC-DAD and HPLC-MS. The chemosystematic impact of the new sesquiterpenoid is discussed briefly.

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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