Synthesis of novel substituted 4H-chromenes and their antioxidant screening


ABSTRACT:

Novel substituted 4H-chromenes were synthesized via O-alkylation of 2-amino-7-hydroxy-4-phenyl-4H-chromene-3- carbonitrile (1) followed by hydrazinolysis to give the hydrazide 3. This key intermediate 3 was reacted with aromatic aldehydes, arylmethylenemalononitriles and substituted isothiocyanates to yield compounds 4a&b and 5a&b, respectively. In addition, cyclization of 5a&b in piperidine yielded the target thiazolo derivatives 6a&b. All newly synthesized compounds were evaluated for their in vitro antioxidant activity. Compound 5a was found to be the most potent antioxidant and the least active among the series being compound 1.

Further details visit: http://www.jocpr.com/

For more details PDF Link: http://www.jocpr.com/articles/synthesis-of-novel-substituted-4hchromenes-and-their-antioxidant-screening.pdf

Comments

Post a Comment

Popular posts from this blog

Research on the ultra-weak luminescence of maize seeds

Image
ABSTRACT : The ultra-weak luminescence (UWL) feature of plant seeds is investigated. Before UWL measurement, the maize seeds are moistened in distilled water for various periods, which are 2h, 4h, 6h and 8h. And then the seeds are dried to the mass they had before moistened. The UWL measurements are made before and after distilled water injects into measured samples. A kind of double exponential function is proved fitting the tested data well as the coefficient of determination of fitting is above 0.97. It is observed that UWL properties of different samples have obvious regularities. The dry seeds contain a large number of hydrophilic pores, so water quickly permeates into maize seeds and forces the seeds to produce stress UWL after water injection. The intensity of UWL depends on the structure of seeds and the time of moistening. Over a period of time, the different UWL intensity of samples decays to the same level as the seeds without moistening. The study results contribute ...
Read more

Adosrption of Rhodomine B on different plant leaf powder

ABSTRACT : Dyes from industrial and laboratory waste are major water pollutants. Most of the dyes are stable to degradation. In this, the removal of Rhodamine-B from its aqueous solutions by adsorption on different plant leaf powder such as Annona squamosa, Manilkara zapota and Prosopis julifora were studied. The effects of various experimental parameters on adsorption such as pH, dye concentration and sorbent dosage were examined and the optimal experimental conditions were evaluated. The maximum removal of color was achieved by Annona squamosa with dosage of 1gm/100ml of effluent at neutral pH. In acidic pH (5.6) Manilkara zapota reduced more color (68.33%). Further details for more articles: http://www.jocpr.com/ For more details PDF Link :  http://www.jocpr.com/articles/adosrption-of-rhodomine-b-on-different-plant-leaf-powder.pdf
Read more

Free radical scavenging activity of methanolic extract of brown alga Spatoglossum asperum

ABSTRACT: The methanolic extract of Spatoglossum asperum showed radical scavenging activity against DPPH, ABTS, superoxide and nitric oxide radicals. Although the concentrations of methanolic extract of S.asperum. for antioxidant activity were much higher than that of standard drugs when tested in various assays, their maximal effects were approximately the same. For antioxidant activities, the methanolic extracts showed an increase with increasing concentration (between 100 and 900 µg/ml) indicating the dose dependency of these algal extract. The significant free radical scavenging activity of Spatoglossum asperum indicated that it could be a potential source of natural antioxidant lead molecules. Further details @ http://www.jocpr.com/ For more details @  http://www.jocpr.com/articles/free-radical-scavenging-activity-of-methanolic-extract-of-brown-alga-spatoglossum-asperum.pdf
Read more