scholarly journals Flavonoids from flowers of Cephalaria pastricenis and their antiradical activity

2004 ◽  
Vol 69 (11) ◽  
pp. 883-886 ◽  
Author(s):  
Dejan Godjevac ◽  
Vlatka Vajs ◽  
Nebojsa Menkovic ◽  
Vele Tesevic ◽  
Pedja Janackovic ◽  
...  
Keyword(s):  
Acid Hydrolysis ◽  
Spectral Data ◽  
13C Nmr ◽  
Antiradical Activity ◽  
Flavonoid Glycosides ◽  
Dpph Assay ◽  
Endemic Plant ◽  
1H And 13C Nmr ◽  
Vis Spectroscopy ◽  
Endemic Plant Species

Two flavonoid glycosides 1 and 2 having the luteolin structure were isolated from flowers of the endemic plant species Cephalaria pastricensis. They were identified by 1H and 13C NMR, as well as UV/Vis spectroscopy. The structures of 1 and 2 were also confirmed by the spectral data of aglycones and TLC of the sugars obtained after acid hydrolysis. Flavones 1 and 2 showed significant antiradical activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay.

8-Acyl-7-phenylbicyclo[2.2.2]-2,6-diones by rearrangement of 3-acyloxy-5-(2-phenylethenyl)-2-cyclohexen-1-ones. 1H and 13C NMR spectral evidence of their structure

1990 ◽  
Vol 55 (5) ◽  
pp. 1208-1215 ◽  
Author(s):  
Pavel Hrnčiar ◽  
Tibor Liptay ◽  
Ján Šraga
Keyword(s):  
Double Bond ◽  
Spectral Data ◽  
13C Nmr ◽  
1H And 13C Nmr ◽  
Spectral Evidence ◽  
C Nmr

3-Acyloxy-5-(2-phenylethenyl)-2-cyclohexen-1-ones II were prepared by O-acylation of 5-(2-phenylethenyl)-1,3-cycloxanedione (I). Treatment of II with AlCl3 resulted in rearrangement of the acyl group to the double bond of the phenylethenyl grouping followed by cyclization to 8-acyl-7-phenylbicyclo[2.2.2]octane-2,6-diones III. Their structure was evidenced by analysis of the 1H and 13C NMR spectral data.

SYNTHESIS AND CHARACTERIZATION OF HETEROCYCLIC CHALCONES CONTAINING HALOGENATED THIOPHENES

2015 ◽  
Vol 77 (3) ◽  
Author(s):  
Helmi Mohammed Al-Maqtari ◽  
Joazaizulfazli Jamalis ◽  
Hasnah Mohd Sirat
Keyword(s):  
Sodium Hydroxide ◽  
Spectral Data ◽  
13C Nmr ◽  
Basic Medium ◽  
Synthesis And Characterization ◽  
Schmidt Reaction ◽  
Synthetic Compounds ◽  
1H And 13C Nmr ◽  
Heterocyclic Aldehydes

Heterocyclic chalcones containing halogenated thiophenes were synthesized. The first step was to synthesize 3-acetyl-2,5-dichlorothiophene and 2-acetyl-5-chlorothiophene as heterocyclic ketones by using Friedel-Crafts acylation. The ketones were then used to synthesize thiophene chalcones through Claisen-Schmidt reaction with the respective heterocyclic aldehydes such as 5-bromothiophene-2-carbaldehyde, 3-methyl-2-thiophene carboxaldehyde and 2-thiophene carboxaldehyde with 3-acetyl-2,5-dichlorothiophene or 2-acetyl-5-chlorothiophene in presence of basic medium, sodium hydroxide to form the corresponding chalcones. Structures of the synthetic compounds were confirmed by IR, MS, 1H and 13C NMR spectral data.

scholarly journals Correlation analysis of IR, 1H and 13C NMR spectral data of N-alkyl and N-cycloalkyl cyanoacetamides

2011 ◽  
Vol 17 (3) ◽  
pp. 307-314 ◽  
Author(s):  
Aleksandar Marinkovic ◽  
Jelena Nedeljkovic ◽  
Dusan Mijin ◽  
Natasa Ilic ◽  
Slobodan Petrovic
Keyword(s):  
Spectral Data ◽  
13C Nmr ◽  
Ethyl Cyanoacetate ◽  
Substituent Effects ◽  
Alkyl Substituent ◽  
Steric Interaction ◽  
1H And 13C Nmr ◽  
Linear Free Energy ◽  
Energy Relationships ◽  
Reverse Substituent Effect

Linear free energy relationships (LFER) were applied to the IR, 1H and 13C NMR spectral data in Nalkyl and N-cycloalkyl cyanoacetamides. N-alkyl and N-cycloalkyl cyanocetamides were synthesized from corresponding amine and ethyl cyanoacetate. A number of substituents were employed for alkyl substitution, and fairly good correlations were obtained, using simple Hammett equation. In N-alkyl and N-cycloalkyl cyanoacetamides substituent cause SCS of N-H hydrogen primarily by steric interaction, polar subtituent effect influences SCS shift of C=O carbon, while steric effect of N-alkyl substituent causes IR stretching frequencies of N-H, C=O and CN group. The conformations of investigated compounds have been studied by the use of semiempirical PM6 method, and together with LFER analysis, give a better insight into the influence of such a structure on the transmission of electronic substituent effects. Negative ? values for several correlations (reverse substituent effect) were found.

scholarly journals A HOPANE TRITERPENOID FROM THE MYCELIUM OF Isaria japonica IN VIETNAM

2017 ◽  
Vol 55 (5) ◽  
pp. 535
Author(s):  
Nguyen Ngoc Tuan ◽  
Tran Thi Kim Anh ◽  
Ping-Chung Kuo ◽  
Tran Dinh Thang
Keyword(s):  
Spectral Data ◽  
13C Nmr ◽  
Methanol Extract ◽  
2D Nmr ◽  
1H And 13C Nmr ◽  
Nmr Techniques ◽  
First Time

A hopane triterpenoid (11b, 22-dihydroxyhopane) was isolated from the methanol extract of the mycelium of Isaria japonica in Vietnam. The structure of this compound was elucidated using a combination of 1D and 2D NMR techniques (1H-, 13C-NMR, COSY, HSQC and HMBC). In the study, we reported the comprehensive 1H- and 13C-NMR spectral data of 11b, 22-dihydroxyhopane for the first time.

scholarly journals AN EFFICIENT THREE COMPONENT ONE-POT SYNTHESIS OF -1,2,3,4-TETRAHYDRO-4-OXO- 6-(5-SUBSTITUTED 2-PHENYL-1H-INDOL-3-YL)-2-THIOXOPYRIMIDINE-5-CARBONITRILE AS ANTIMICROBIAL AND ANTITUBERCULAR AGENTS

2021 ◽  
pp. 94-97
Author(s):  
PRABHAKER WALMIK
Keyword(s):  
Spectral Data ◽  
13C Nmr ◽  
Antitubercular Agents ◽  
Mass Spectral Data ◽  
One Pot ◽  
1H And 13C Nmr ◽  
Spectral Techniques ◽  
Mass Spectral ◽  
One Pot Synthesis

Objective: The objective of the study was to synthesis of 1,2,3,4-tetrahydro-4-oxo-6-(5-substituted 2-phenyl-1H-indol-3-yl)-2-thioxopyrimidine-5- carbonitrile derivatives (4a-c). Methods: The structures of all these unknown compounds have been confirmed with the help of physical and spectral techniques such as IR, 1H, and 13C NMR and mass spectral data and these newly synthesized compounds were evaluated for in-vitro antimicrobial and antitubercular activities. Results: Screening studies have demonstrated that the newly synthesized compound 4a exhibited promising antimicrobial and antitubercular properties. Conclusion: The final results revealed that compound 4a exhibited promising antimicrobial and antitubercular properties when compared to the standard drugs.

A METHOD FOR PREPARATION OF DROSERONE FROM PLUMBAGIN

INDIAN DRUGS ◽  
2013 ◽  
Vol 50 (05) ◽  
pp. 53-56
Author(s):  
G.M Ferreira ◽  
◽  
K.S. Laddha
Keyword(s):  
Nucleophilic Substitution ◽  
Spectral Data ◽  
Hydroxy Group ◽  
13C Nmr ◽  
Plumbago Zeylanica ◽  
1H And 13C Nmr ◽  
Naturally Occurring ◽  
Rp Hplc

Droserone (2,5-dihyrdoxy-3-methyl-1,4- naphthoquinone) was prepared from naturally occurring naphthoquinone plumbagin. Plumbagin was isolated from roots of Plumbago zeylanica. Plumbagin was first brominated at C-3 which was subsequently substituted with hydroxy group by a nucleophilic substitution to obtain Droserone. The synthesized compounds were characterized by IR, MS, 1H and 13C NMR spectral data. RP-HPLC was used to ascertain the purity of the obtained compound.

1H- and 13C-Nmr Spectral Data of Five Sarpagine-type Alkaloids

Heterocycles ◽  
1996 ◽  
Vol 43 (5) ◽  
pp. 1015 ◽  
Author(s):  
Mauri Lounasmaa ◽  
Reija Jokela
Keyword(s):  
Spectral Data ◽  
13C Nmr ◽  
1H And 13C Nmr
Sign in / Sign up

Export Citation Format

Share Document