title: Synthesis of new spiroindolinones incorporating a benzothiazole moiety as antioxidant agents.
abstract: 3H-Spiro[1,3-benzothiazole-2,3'-indol]-2'(1'H)-ones 3a-c and 4a-e were synthesized from treating the 5-substituted 1H-indole-2,3-diones with 2-aminothiophenol in ethanol. The structures were confirmed by elemental analyses, spectrometry (IR, (1)H NMR, (13)C NMR, HSQC-2D and LCMS-APCI) and single crystal X-ray analysis. The new compounds were screened for their antioxidant activities such as the Fe(3+)/ascorbate system induced inhibition of lipid peroxidation (LP) in liposomes, trolox equivalent antioxidant capacity (TEAC), scavenging effect on diphenylpicryl hydrazine (DPPH*), and reducing power. These compounds showed potent scavenging activities against DPPH* and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS*(+)) radicals, reducing powers, and strong inhibitory capacity on lipid peroxidation. Compound 4a incorporating methyl both at R(1) and R(2) was found to be the most potent antioxidant described in this study. Compounds 3b and 4b were selected as representative compounds by the National Cancer Institute for screening against anticancer activity and these compounds were found to be cytotoxic against CNS cancer cell line SNB-75 in the primary screen.
authors.affiliation: Faculty of Pharmacy, Department of Pharmaceutical Chemistry, Istanbul University, 34116 Beyazit, Istanbul, Turkey.
authors.forename: Nilgün
authors.initials: N
authors.lastname: Karali
authors.forename: Ozlen
authors.initials: O
authors.lastname: Güzel
authors.forename: Nurten
authors.initials: N
authors.lastname: Ozsoy
authors.forename: Süheyla
authors.initials: S
authors.lastname: Ozbey
authors.forename: Aydin
authors.initials: A
authors.lastname: Salman
mesh_terms: D000970:Antineoplastic Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D000975:Antioxidants / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D052160:Benzothiazoles / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D045744:Cell Line, Tumor; D018360:Crystallography, X-Ray; D006801:Humans; D007211:Indoles / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure; D013141:Spiro Compounds / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000970:Antineoplastic Agents; D000975:Antioxidants; D052160:Benzothiazoles; D007211:Indoles; D013141:Spiro Compounds