名称:
Antioxidant and antimicrobial studies of novel N′-(substituted-2-chloroquinolin-3-yl)methylidene-4-hydroxy-2H-1,2-benzothiazine-3-carbohydrazides 1,1-dioxides
摘要:
N'-(2-Chloroquinolin-3-yl)methylidene-4-hydroxy-2H-1,2-benzothiazine-3-carbohydrazides 1,1-dioxide (4a-4j) were prepared starting from corresponding methyl 4-hydroxy-2H-1,2-benzothiazine-3-carboxylate (1a and 1b) by condensation with hydrazine hydrate, followed by treatment with substituted 2-chloro-3-formyl quinolines (3a-3e) under ultrasonic irradiation. On the other hand, substituted 2-chloro-3-formyl quinolines were prepared in a facile way from respective acetanilides under microwave irradiation in very short duration of time (1.5-3.0 min) obtaining excellent yields. The compounds (4a-4j) were tested for their superoxide scavenging and antimicrobial activities. Almost all the compounds showed moderate superoxide scavenging activity and compounds 4a, 4d, 4g, and 4j were found active against gram-positive bacterial strains. In addition, 4a, 4e, and 4i were active against fungi (Aspergillus flavus, Aspergillus niger, Fusarium oxysporum).