2-Phenyl-6(7)-R-substituted quinoxalines N-oxides. Synthesis, structure elucidation and antimicrobial activity

1990 ◽  
Vol 25 (6) ◽  
pp. 527-532 ◽  
Author(s):  
M Loriga ◽  
A Nuvole ◽  
G Paglietti ◽  
G Fadda ◽  
S Zanetti
Planta Medica ◽  
2011 ◽  
Vol 77 (12) ◽  
Author(s):  
A Debbab ◽  
R Bara ◽  
A Pretsch ◽  
R Edrada Ebel ◽  
V Wray ◽  
...  

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1094
Author(s):  
Melissa M. Cadelis ◽  
Soeren Geese ◽  
Benedict B. Uy ◽  
Daniel R. Mulholland ◽  
Shara J. van de Pas ◽  
...  

Antimicrobial bioassay-guided fractionation of the endophytic fungi Neofusicoccum australe led to the isolation of a new unsymmetrical naphthoquinone dimer, neofusnaphthoquinone B (1), along with four known natural products (2–5). Structure elucidation was conducted by nuclear magnetic resonance (NMR) spectroscopic methods, and the antimicrobial activity of all the natural products was investigated, revealing 1 to be moderately active towards methicillin-resistant Staphylococcus aureus (MRSA) with a minimum inhibitory concentration (MIC) of 16 µg/mL.


Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3235
Author(s):  
Melissa M. Cadelis ◽  
Hugo Gordon ◽  
Alex Grey ◽  
Soeren Geese ◽  
Daniel R. Mulholland ◽  
...  

Fungi have become an invaluable source of bioactive natural products, with more than 5 million species of fungi spanning the globe. Fractionation of crude extract of Neodidymelliopsis sp., led to the isolation of a novel polyketide, (2Z)-cillifuranone (1) and five previously reported natural products, (2E)-cillifuranone (2), taiwapyrone (3), xylariolide D (4), pachybasin (5), and N-(5-hydroxypentyl)acetamide (6). It was discovered that (2Z)-cillifuranone (1) was particularly sensitive to ambient temperature and light resulting in isomerisation to (2E)-cillifuranone (2). Structure elucidation of all the natural products were conducted by NMR spectroscopic techniques. The antimicrobial activity of 2, 3, and 5 were evaluated against a variety of bacterial and fungal pathogens. A sodium [1-13C] acetate labelling study was conducted on Neodidymelliopsis sp. and confirmed that pachybasin is biosynthesised through the acetate polyketide pathway.


2018 ◽  
Vol 13 (9) ◽  
pp. 1934578X1801300
Author(s):  
Bruna de Falco ◽  
Giuliano Bonanomi ◽  
Virginia Lanzotti

A bioassay guided phytochemical analysis of the bulbs of Allium sativum L. var. Voghiera, typical of Voghiera, Ferrara (Italy), allowed the isolation of six new sulfur compounds with dithiosulfinates and sulfoxides functionalities. Structure elucidation of the isolated compounds was carried out by spectroscopic analyses, including NMR spectroscopy and MS spectrometry. Compounds showed significant antimicrobial activity towards two fungal species, the air-borne pathogen Botrytis cinerea and the beneficial fungus Trichoderma harzianum.


1987 ◽  
Vol 40 (7) ◽  
pp. 1327 ◽  
Author(s):  
RJ Capon ◽  
JK Macleod

A new sesterterpene tetronic acid* (2), exhibiting antimicrobial activity, has been isolated from an Australian Ircinia species. The structure elucidation was based on detailed spectroscopic analysis of (2), its acetate (3), and two methylated derivatives (4) and (5).


Planta Medica ◽  
2021 ◽  
Author(s):  
Fazila Zulfiqar ◽  
Pankaj Pandey ◽  
Siddharth K. Tripathi ◽  
Zulfiqar Ali ◽  
Amar G. Chittiboyina ◽  
...  

AbstractTwo monobenzoylcyclopropane (hypoxhemerol A (1) and hypoxhemeroloside G (2)) and three dibenzoylcyclopropane (hypoxhemerol B (3), hypoxhemeroloside H (4), and hypoxhemeroloside I (5)) derivatives were isolated from the hydro-alcoholic extract of Hypoxis hemerocallidea corms. This is the first instance where benzoylcyclopropane analogs were isolated from any natural source. Structure elucidation was mainly based on 1D- and 2D-NMR and HRESIMS data. The absolute configuration (2R, 4R) of 1 was determined via NOESY NMR and experimental and calculated ECD data analyses. Compounds 1–5 and 11 recently reported metabolites (hypoxoside, obtuside A, interjectin, acuminoside, curcapicycloside, and hypoxhemerolosides A – F) were screened for in vitro antimicrobial activity against various bacterial and fungal strains. Curcapicycloside and acuminoside exhibited antibacterial activity against Escherichia coli with 78 and 79% inhibition at 20 µg/mL, respectively. Hypoxhemeroloside A showed mild antifungal activity against Cryptococcus neoformans with 63% inhibition at 20 µg/mL.


Sign in / Sign up

Export Citation Format

Share Document