scholarly journals Flavonoids from Tephrosia Calophylla

2009 ◽  
Vol 4 (1) ◽  
pp. 1934578X0900400
Author(s):  
Ramireddy V. Narahari Reddy ◽  
Shaik I. Khalivulla ◽  
Bandi A.K. Reddy ◽  
Mopuru V. Bhaskar Reddy ◽  
Duvvuru Gunasekar ◽  
...  
Keyword(s):  
2D Nmr ◽  
Spectral Studies

Two new flavanones, (2S)-5-hydroxy-7,4′-di-O-(γ,γ-dimethylallyl)flavanone (1) and 6-hydroxy- E-3-(2,5-dimethoxy-benzylidine)-2′,5′-dimethoxyflavanone (2), together with three known compounds, tephrowatsin C, afrormosin and kaempferol 3-O-β-D-glucopyranoside were isolated from the roots of Tephrosia calophylla. The structures of 1 and 2 were established by extensive 2D NMR spectral studies.

scholarly journals Isolation and Characterization of Crotosparsamide, a New Cyclic Nonapeptide from Croton sparsiflorus

2010 ◽  
Vol 5 (12) ◽  
pp. 1934578X1000501 ◽  
Author(s):  
Rashad Mehmood ◽  
Abdul Malik
Keyword(s):  
Spectroscopic Data ◽  
2D Nmr ◽  
Spectral Studies ◽  
Isolation And Characterization ◽  
First Time

Crotosparsamide (1), a new cyclic nonapeptide, has been isolated from the n-butanol soluble sub-fraction of Croton sparsiflorus along with p-hydroxy methylcinnamate and kaempferol, which are reported for the first time from this species. Their structures were determined by chemical and spectral studies including ESIMS, and 1D and 2D NMR spectroscopic data.

Meso-pyrrolyl BODIPY based colorimetric optical sensor for Cu2+ ions

2020 ◽  
Vol 24 (09) ◽  
pp. 1121-1128
Author(s):  
P. Sabari ◽  
Rima Sengupta ◽  
B. Umasekhar ◽  
Mangalampalli Ravikanth
Keyword(s):  
Schiff Base ◽  
2D Nmr ◽  
Spectral Studies ◽  
Strong Absorption Band ◽  
X Ray ◽  
Mass Spectral ◽  
Imine Nitrogen ◽  
Phenolic Oxygen ◽  
Td Dft ◽  
Cation Sensing

A simple meso-pyrrolyl BODIPY-Schiff base conjugate was synthesized by reacting ([Formula: see text]-formylpyrrolyl) BODIPY with 2-aminophenol in ethanol at reflux followed by recrystallization from CH2Cl2/petroleum ether, affording the conjugate in 72% yield. The conjugate was thoroughly characterized by HR-MS, 1D and 2D NMR and X-ray crystallographic techniques. The X-ray structure of the meso-pyrrolyl BODIPY-Schiff base conjugate revealed that the meso-pyrrole and the phenyl substituents were deviated by an angle of [Formula: see text] and [Formula: see text], respectively, from the plane of the BF2-dipyrrin core. The absorption spectrum of the conjugate was similar to the ([Formula: see text]-formylpyrrolyl) BODIPY with a strong absorption band at 508 nm, whereas the fluorescence of the ([Formula: see text]-formylpyrrolyl) BODIPY was completely quenched in the BODIPY-Schiff base conjugate. Furthermore, cation sensing studies revealed that the conjugate has a specific sensing ability for the Cu(II) ion even in the presence of the other metal ions, as verified by the visual, absorption and mass spectral studies. The DFT optimized structure revealed that the Cu(II) ion was bound to pyrrolic nitrogen, imine nitrogen, phenolic oxygen and two water molecules in a distorted square pyramidal fashion. TD-DFT studies accounted well for the absorption spectra of the BODIPY-Schiff base conjugate and its Cu[Formula: see text] bound complex.

Synthesis and characterization of various unsubstituted and mono-N-substituted tetraazamacrocycles

1995 ◽  
Vol 73 (5) ◽  
pp. 685-695 ◽  
Author(s):  
I. Meunier ◽  
A.K. Mishra ◽  
B. Hanquet ◽  
R. Guilard ◽  
P. Cocolios
Keyword(s):  
Mass Spectrometry ◽  
Template Synthesis ◽  
2D Nmr ◽  
Spectral Studies ◽  
Synthesis And Characterization ◽  
Difference Spectroscopy ◽  
Protective Group ◽  
Noe Difference Spectroscopy ◽  
C Nmr

Syntheses of tetraazamacrocycles have been carried out by using p-toluenesulfonyl chloride as protective group. The [14(ane) N4] and [15(ane) N4] were also obtained by the template synthesis. Mono-N-functionalization of tetraazamacrocycles was accomplished by reaction of a fivefold excess of the free macrocycles with 1 equivalent of a suitable alkylating or arylating reagent. The key point of the synthesis lies in the use of an excess of the macrocycle over the substituting reactants to reduce the formation of polysubstituted derivatives, and in the easy separation of the excess of unreacted macrocycle. All the products were characterized on the basis of spectral studies (1H and l3C NMR, including 2D NMR and NOE difference studies) and mass spectrometry. Keywords: tetraazamacrocycles, improved synthesis, protective group, N-tosylation, template synthesis, NOE difference spectroscopy.

scholarly journals A Novel Biflavonyloxymethane from Pongamia Pinnata and its Radical Quenching Activity

2011 ◽  
Vol 6 (5) ◽  
pp. 1934578X1100600 ◽  
Author(s):  
Anindita Ghosh ◽  
Suvra Mandal ◽  
Avijit Banerji ◽  
Manoj Kar ◽  
Kalyan Hazra ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
2D Nmr ◽  
Pongamia Pinnata ◽  
Spectral Studies ◽  
Root Bark

The root bark of Pongamia pinnata Pierre (syn P. glabra Vent.) has afforded a new biflavonyloxymethane, pongabiflavone, along with a known furanoflavone, 3-methoxy-(7, 8, 2″, 3″) furanoflavone. The structure of this new compound was elucidated from extensive spectral studies, including 2D-NMR spectroscopic experiments. The antioxidant, radical quenching activity- superoxide and nitric oxide quenching activities of both pongabiflavone and previously isolated karanjabiflavone have been evaluated which can be a key to cure Psoriasis.

scholarly journals A New Carbazole Alkaloid from Murraya koenigii Spreng (Rutaceae)

2008 ◽  
Vol 3 (10) ◽  
pp. 1934578X0800301 ◽  
Author(s):  
Suvra Mandal ◽  
Anupam Nayak ◽  
Samir K. Banerjee ◽  
Julie Banerji ◽  
Avijit Banerji
Keyword(s):  
Medicinal Plant ◽  
2D Nmr ◽  
Spectral Studies ◽  
Murraya Koenigii ◽  
Indian Medicinal Plant ◽  
Carbazole Alkaloids

A new carbazole alkaloid (kurryam) oxygenated at the 4-position, hitherto unknown among carbazole alkaloids, has been isolated from the seeds of an Indian medicinal plant, Murraya koenigii (Rutaceae). The structure has been established as 4-hydroxy-(2′,2′,3)-trimethyl-(6,7)-dimethoxy pyranocarbazole from extensive 2D NMR spectral studies. In addition, two known carbazole alkaloids, (2′,2′,3)-trimethyl 6-methoxy pyranocarbazole and (2′,2′,3)-trimethyl 6-hydroxy pyranocarbazole were isolated from the seeds of the same plant, of which (2′,2′,3)-trimethyl 6-methoxy pyranocarbazole exhibited significant antidiarrhoeal activity, as also did the new compound.

scholarly journals A New Biflavonyloxymethane from Pongamia Pinnata

2010 ◽  
Vol 5 (8) ◽  
pp. 1934578X1000500 ◽  
Author(s):  
Anindita Ghosh ◽  
Suvra Mandal ◽  
Avijit Banerji ◽  
Julie Banerji
Keyword(s):  
Antioxidant Activity ◽  
2D Nmr ◽  
Pongamia Pinnata ◽  
Spectral Studies ◽  
Root Bark ◽  
Pongamia Glabra

The root bark of Pongamia pinnata Pierre Syn Pongamia glabra (Family: Fabaceae) has afforded a new biflavonyloxymethane, karanjabiflavone, along with a known furanoflavone, pongapin. The structure of this new biflavonyloxymethane was elucidated from extensive spectral studies including 2D-NMR experiments. Both of these compounds possess antioxidant activity.

Synthesis, Fourier transform infrared, 1D and 2D NMR spectral studies on the conformation of two new cholesteryl 4-alkoxyphenyl-4′ benzoates

2004 ◽  
Vol 687 (1-3) ◽  
pp. 57-64 ◽  
Author(s):  
Guan-Yeow Yeap ◽  
Sie-Tiong Ha ◽  
Masato M. Ito ◽  
Peng-Lim Boey ◽  
Wan Ahmad Kamil Mahmood
Keyword(s):  
Fourier Transform ◽  
Fourier Transform Infrared ◽  
2D Nmr ◽  
Spectral Studies

scholarly journals Sulfated Triterpene Glycosides from Zygophyllum Fabago

2007 ◽  
Vol 2 (11) ◽  
pp. 1934578X0700201 ◽  
Author(s):  
Viqar Uddin Ahmad ◽  
Saleha Suleman Khan ◽  
Amir Ahmed ◽  
Afsar Khan ◽  
Umar Farooq ◽  
...  
Keyword(s):  
Ursolic Acid ◽  
2D Nmr ◽  
Triterpene Glycosides ◽  
Spectral Studies ◽  
Sodium Salts ◽  
Aerial Parts ◽  
Derivatives Of

From the aerial parts of Zygophyllum fabago from Turkey, two new sodium salts of sulfated glycoside derivatives of ursolic acid, named as zygofaboside A (1) and zygofaboside B (2) have been isolated. Their structures were elucidated through spectral studies, including 2D-NMR spectroscopic experiments (HMQC, HMBC, COSY and NOESY).

Ziziphorins A and B. New Flavonoids from Ziziphora tenuior

2010 ◽  
Vol 65 (11) ◽  
pp. 1397-1400 ◽  
Author(s):  
Rashad Mehmood ◽  
Muhammmad Imran ◽  
Abdul Malik ◽  
Rasool Bakhsh Tareen
Keyword(s):  
Ursolic Acid ◽  
Oleanolic Acid ◽  
Spectroscopic Data ◽  
Soluble Fraction ◽  
2D Nmr ◽  
Spectral Studies

Ziziphorins A (1) and B (2), new flavonoids, have been isolated from the chloroform-soluble fraction of Ziziphora tenuior along with 1-hentetracontanol, β -sitosterol-3-O-β -D-glucoside, ursolic acid, oleanolic acid, and apigenin. Their structures were assigned from spectral studies including 1D and 2D NMR spectroscopic data

scholarly journals Bioluminescence chemistry of fireworm Odontosyllis

2019 ◽  
Vol 116 (38) ◽  
pp. 18911-18916 ◽  
Author(s):  
Alexey A. Kotlobay ◽  
Maxim A. Dubinnyi ◽  
Konstantin V. Purtov ◽  
Elena B. Guglya ◽  
Natalja S. Rodionova ◽  
...  
Keyword(s):  
Light Emission ◽  
Structural Similarity ◽  
2D Nmr ◽  
Spectral Studies ◽  
Low Molecular Weight ◽  
X Ray Diffraction ◽  
2D Nmr Spectroscopy ◽  
Luciferase Enzyme ◽  
Sulfur Containing ◽  
Bright Blue

Marine polychaetes Odontosyllis undecimdonta, commonly known as fireworms, emit bright blue-green bioluminescence. Until the recent identification of the Odontosyllis luciferase enzyme, little progress had been made toward characterizing the key components of this bioluminescence system. Here we present the biomolecular mechanisms of enzymatic (leading to light emission) and nonenzymatic (dark) oxidation pathways of newly described O. undecimdonta luciferin. Spectral studies, including 1D and 2D NMR spectroscopy, mass spectrometry, and X-ray diffraction, of isolated substances allowed us to characterize the luciferin as an unusual tricyclic sulfur-containing heterocycle. Odontosyllis luciferin does not share structural similarity with any other known luciferins. The structures of the Odontosyllis bioluminescent system’s low molecular weight components have enabled us to propose chemical transformation pathways for the enzymatic and nonspecific oxidation of luciferin.

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