New spiroindolinones bearing 5-chlorobenzothiazole moiety

Abstract

In this study, 5-chloro-3H-spiro-[1,3-benzothiazole-2,3'-indole]-2'(1'H)-one derivatives 3a-l were synthesized by the reaction of 1H-indole-2,3-diones 1a-l with 2-amino-4-chlorothiophenol 2 in ethanol. 3a-l were tested for their abilities to inhibit lipid peroxidation (LP), scavenge DPPH(•) and ABTS(•+) radicals, and to reduce Fe(3+) to Fe(2+). Most of the tested compounds exhibited potent scavenging activities against ABTS(•+) radical, reducing powers and strong inhibitory capacity on LP. 3 a, 3 d, 3 e, 3h, 3 j and 3 k chosen as prototypes were evaluated in the National Cancer Institute's in vitro primary anticancer assay. The greatest growth inhibitions were observed against a non-small cell lung cancer cell line HOP-92 for R1-fluoro substituted 3 d and a renal cancer cell line RXF-393 for R-chloro substituted 3 e in the primary screen.

Keywords: Anticancer activity; antioxidant activity; benzothiazole; spiroindolinone; synthesis.