New spiroindolinones bearing 5-chlorobenzothiazole moiety.

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.

5-Chloro-benzothia-zole-2-spiro-3'-indolin-2'-one.

The title compound, C(14)H(9)ClN(2)OS, crystallizes with two unique mol-ecules, A and B, in the asymmetric unit. The five-membered rings of the benzothia-zole groups in both mol-ecules adopt an envelope conformation [puckering parameters: q(2) = 0.242 (1) Šand ϕ(2) = 217.5 (4)° for A, and q(2) = 0.234 (1) Šand ϕ(2) = 37.7 (4)° for B]. The five-membered rings of the indolinone groups in both mol-ecules are also not planar, with a twisted conformation [puckering parameters are q(2) = 0.112 (2) Šand ϕ(2) = 126.3 (8)° for A, and q(2) = 0.108 (2) Šand ϕ(2) = 306.4 (9)° for B]. In the crystal structure, there are inter-molecular N-H⋯O, N-H⋯S and C-H⋯O hydrogen-bonding inter-actions, forming the layers propagating normal to c.