Krishnendu B. Sahu

Amberlite-IRA-402 (OH) ion exchange resin mediated synthesis of indolizines, pyrrolo [1,2-a] quinolines and isoquinolines: Antibacterial and antifungal evaluation of the products

A number of indolizines and pyrrolo[1,2-a]quinolines/isoquinolines were prepared from phenacyl pyridinium, quinolinium and isoquinolinium salts derived from the reaction of the heterocycles with 2-bromo acetophenone with alkynes and alkenes using amberlite-IRA-402 (OH) ion exchange resin as the base. Antibacterial and antifungal studies were carried out against thirteen bacterial and four fungal strains, which revealed that three derivatives (4a, 4b, 7a) out of fifteen are effective against all the thirteen strains and one derivative, 10, showed dual antibactericidal and antifungal efficacy.

Efficient synthesis of 3,3-diheteroaromatic oxindole analogues and their in vitro evaluation for spermicidal potential

Syntheses of 3,3-diheteroaromatic oxindole derivatives has been achieved by coupling indole-2,3-dione (isatin) with differently substituted indoles and pyrrole in presence of I(2) in i-PrOH. The in vitro spermicidal potentials and the mode of spermicidal action of the synthesized analogues were evaluated and the derivative, 3,3-bis (5-methoxy-1H-indol-3-yl) indolin-2-one (3d) exhibited most significant activity.

I2 catalyzed Friedel–Crafts alkylation reaction of substituted anilines with ninhydrin: formation of novel products and their antimicrobial evaluation

Friedel–Crafts reaction of differently substituted anilines with ninhydrin in the presence of molecular iodine at ambient temperature constitutes a facile, cost effective, and regioselective synthesis of a series of 2-mono/2,2-bis-(amino-phenyl)-indane-1,3-dione derivatives. Under identical conditions, use of different substituents in aniline ring led to the formation of different products, emphasizing the pivotal role of the nature and position of the substituents in product formation. In vitro antimicrobial activity evaluation of the synthesized molecules against eight bacterial and four fungal strains revealed that four of them possess duel efficacies (bactericidal as well as fungicidal). The activities are attributed to the disruption of architecture of the microbes as revealed from ultrastructural studies (SEM).Graphical Abstract

Palladium-Catalyzed 8-Exo Trig Intramolecular Heck Reaction Under Microwave Irradiation in the Presence of Basic Alumina

Abstract The Heck cross-coupling reaction has been employed for efficient conversion of quinolines to benzoxocinoquinoline through a microwave-assisted palladium-catalyzed intramolecular cyclization in the presence of basic alumina. GRAPHICAL ABSTRACT