scholarly journals Two New Glycosides from Conyza bonariensis

2010 ◽  
Vol 5 (7) ◽  
pp. 1934578X1000500 ◽  
Author(s):  
Aqib Zahoor ◽  
Imran Nafees Siddiqui ◽  
Afsar Khan ◽  
Viqar Uddin Ahmad ◽  
Amir Ahmed ◽  
...  

Studies on Conyza bonariensis (L.) Cronq. led to the isolation of two new glycosides trivially named as erigeside E and F (1–2), along with two new source compounds; benzyl-β-D-glucopyranoside (3) and 2-phenylethyl-β-D-glucopyranoside (4). Compounds 1, 3, and 4 are aromatic glycosides, while compound 2 is an alkyl glycoside. Their structures were elucidated through mass spectrometric, and 1D- and 2D-NMR spectroscopic techniques, including 1H NMR, 13C NMR, HMQC, HSQC and HMBC.

2016 ◽  
Vol 71 (11-12) ◽  
pp. 387-392 ◽  
Author(s):  
Samar S.A. Mourshid ◽  
Jihan M. Badr ◽  
April L. Risinger ◽  
Susan L. Mooberry ◽  
Diaa T.A. Youssef

Abstract Two new antimicrobial fatty acid esters, penicilloitins A and B (1 and 2), along with α-cyclopiazonic acid (3), tryptamine (4) and indole-3-carbaldehyde (5), were isolated from mycelial extracts and the culture broth of a marine endophytic Penicillium species and their structures established by spectroscopic techniques including 1D (1H NMR and 13C NMR) and 2D NMR (COSY, multiplicity-edited HSQC, and HMBC) as well as HRESIMS. Of these compounds, 1, 3 and 4 displayed modest antimicrobial activity.


1995 ◽  
Vol 60 (4) ◽  
pp. 619-635 ◽  
Author(s):  
Václav Křeček ◽  
Stanislav Hilgard ◽  
Miloš Buděšínský ◽  
Alois Vystrčil

A series of derivatives with various oxygen functionalities in positions 17,22a or 19,20 was prepared from diene I and olefin XVI by addition and oxidation reactions. The structure of the obtained compounds was confirmed by 1H NMR, 13C NMR and IR spectroscopy. The kind of intramolecular association of the 17α-hydroxy group was studied in connection with modification of the side chain and substitution in position 22a. Complete assignment of the hydrogen signals and most of the coupling constants was accomplished using a combination of 1D and 2D NMR techniques. The 1H and 13C NMR spectra are discussed.


2018 ◽  
Vol 14 ◽  
pp. 3011-3017
Author(s):  
Akın Sağırlı ◽  
Yaşar Dürüst
Keyword(s):  
2D Nmr ◽  
X Ray ◽  
H Nmr ◽  
Tof Ms ◽  

The present work describes an unfamiliar reaction of 5-(chloromethyl)-3-substituted-phenyl-1,2,4-oxadiazoles with KCN affording trisubstituted 1,2,4-oxadiazol-5-ylacetonitriles and their parent alkanes, namely, 1,2,3-trisubstituted-1,2,4-oxadiazol-5-ylpropanes. To the best of our knowledge, the current synthetic route leading to decyanated products will be the first in terms of a decyanation process which allows the transformation of trisubstituted acetonitriles into alkanes by the incorporation of KCN with the association of in situ-formed HCN and most likely through the extrusion of cyanogen which could not be detected or isolated. In addition, the plausible mechanisms were proposed for both transformations. The structures of the title compounds were identified by means of IR, 1H NMR, 13C NMR, 2D NMR spectra, TOF–MS and X-ray measurements.


2006 ◽  
Vol 61 (9) ◽  
pp. 1153-1157 ◽  
Author(s):  
Bernadete P. da Silva ◽  
José P. Parente

Abstract A new bidesmosidic furostanol saponin was isolated from leaves of Furcraea gigantea Vent. Its structure was established as 3-[(O-6-deoxy-α-L-mannopyranosyl-(1→4)-O-β -D-glucopyranosyl-( 1→3)-O-[O-β -D-glucopyranosyl-(1→3)-β -D-glucopyranosyl-(1→2)-O-β -D-glucopyranosyl- (1→4)-β -D-galactopyranosyl)oxy]-(3β ,5α,15α,22α,25R)-26-(β -D-glucopyranosyloxy)-15,22-dihydroxy- furost-12-one. Its structural identification was performed using detailed analyses of 1H and 13C NMR spectra including 2D NMR spectroscopic techniques (DEPT, COSY, HETCOR and COLOC) and chemical conversions. The steroidal saponin showed no haemolytic effects in the in vitro assays and demonstrated inhibition of the capillary permeability activity.


2012 ◽  
Vol 8 ◽  
pp. 1400-1405 ◽  
Author(s):  
Suri Babu Madasu ◽  
Nagaji Ambabhai Vekariya ◽  
M N V D Hari Kiran ◽  
Badarinadh Gupta ◽  
Aminul Islam ◽  
...  

Eletriptan hydrobromide (1) is a selective serotonin (5-HT1) agonist, used for the acute treatment of the headache phase of migraine attacks. During the manufacture of eletriptan hydrobromide the formation of various impurities were observed and identified by LC–MS. To control the formation of these impurities during the preparation of active pharmaceutical ingredients, the structure of the impurities must be known. Major impurities of the eletriptan hydrobromide synthesis were prepared and characterized by using various spectroscopic techniques, i.e., mass spectroscopy, FTIR , 1H NMR, 13C NMR/DEPT, and further confirmed by co-injection in HPLC. The present study will be of great help in the synthesis of highly pure eletriptan hydrobromide related compounds.


2010 ◽  
Vol 65 (5) ◽  
pp. 628-634 ◽  
Author(s):  
Bernadete P. da Silva ◽  
José P. Parente

A new complex triterpenoid saponin, polystachyasaponin, was isolated from leaves of Entada polystachya (L.) DC. (Leguminosae) by using chromatographic methods. Its structure was established as 15,16-dihydroxy-3-[[O-β -D-xylopyranosyl-(1→2)-O-α-L-arabinopyranosyl-(1→6)-2- (acetylamino)-2-deoxy-β -D-glucopyranosyl]oxy]-(3β ,15α,16α)-olean-12-en-28-oic acid O-D-apio- β -D-furanosyl-(1→3)-O-β -D-xylopyranosyl-(1→2)-O-[β -D-glucopyranosyl-(1→4)]-6-O-[(2E,6R)- 6-hydroxy-2,6-dimethyl-1-oxo-2,7-octadienyl]-β -D-glucopyranosyl ester. Structural elucidation was performed using detailed analyses of 1H and 13C NMR spectra including 2D NMR spectroscopic techniques and chemical conversions. The hemolytic activity of the saponin was evaluated using in vitro assays, and its adjuvant potential on the cellular immune response against ovalbumin antigen was investigated using in vivo assays.


2004 ◽  
Vol 59 (1-2) ◽  
pp. 81-85 ◽  
Author(s):  
Bernadete P. da Silva ◽  
José P. Parente

Two new steroidal saponins were isolated from the rhizomes of Costus spiralis Rosc. Their structures were established as (3β,25R)-26-(β-ᴅ-glucopyranosyloxy)-22-hydroxyfurost-5- en-3-ylO-d-apio-β-ᴅ-furanosyl-(1→2)-O-[α-ʟ-rhamnopyranosyl-(1→4)]-β-ᴅ-glucopyranoside (1) and (3β,25R)-26-(β-ᴅ-glucopyranosyloxy)-22-hydroxyfurost-5-en-3-yl O-ᴅ-apio-β-ᴅ-furanosyl-( 154)-O-[α-ʟ-rhamnopyranosyl-(1→2)]-β-ᴅ-glucopyranoside (2). Their structural identifications were performed using detailed analyses of 1H and 13C NMR spectra including 2D NMR spectroscopic techniques (DEPT, COSY, HETCOR and COLOC) and chemical conversions. The steroidal saponins were evaluated for anti-inflammatory activity.


2009 ◽  
Vol 64 (7-8) ◽  
pp. 513-517 ◽  
Author(s):  
Ahmed A. Mahmoud ◽  
Shar S. Al-Shihry ◽  
Mohamed-Elamir F. Hegazy

The phloroglucinol glucoside derivative [2,4-dihydroxy-6-(β-D-glucopyranosyloxy)phenyl]- butan-1-one (1), roseoside (2), and kaempferol-3-O-β-D-glucopyranoside (3) were isolated from the aerial parts of Conyza aegyptiaca (L.). To the best of our knowledge, this is the first isolation of compounds 1 - 3 from C. aegyptiaca. Their structures were determined by spectroscopic techniques including, IR, HR-EIMS, and extensive 500 MHz 1D- and 2D-NMR analyses (1H, 13C NMR, DEPT, 1H-1H COSY, HMQC and HMBC experiments). The antioxidant activity of 1, using the DPPH assay, was investigated; in addition, 1 was investigated against different types of cell lines, including Hep-G2, HCT-116, and RAW 264.7 for its cytotoxic effects. Also, this is the first report on the activity of 1.


1982 ◽  
Vol 37 (12) ◽  
pp. 1661-1664 ◽  
Author(s):  
Martin Feigel ◽  
Gerhard Hägele ◽  
Axel Hinke ◽  
Gudrun Tossing

2D NMR ist used to determine the 1H NMR parameters of L-Menthyldichlorophosphine. 13C NMR data are given


Author(s):  
A.M. Shah ◽  
A.J. Rojivadiya

An efficient protocol for the synthesis of imidazo [1,2-a] pyrimidine was developed by using three component one-pot Biginelli synthesis. The synthesized compounds were characterized by spectroscopic techniques like FT-IR, 1H NMR, 13C NMR, and mass spectroscopy.


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