Cigdem Sayil

Synthesis and investigation of antioxidant activity of the dithiocarbamate derivatives of 9,10-anthracenedione

A variety of new derivatives of 9,10-anthracenedione with mono- and bisdithiocarbamate moiety in the non-catalytic conditions have been synthesized. The obtained compounds were screened for their antioxidant capacity using the cupric-reducing antioxidant capacity (CUPRAC) method. Three of the compounds showed CUPRAC-Trolox equivalent antioxidant capacity (TEAC) coefficients higher than trolox. Scavenging effects on reactive oxygen species (ROS), hydroxyl radical scavenging (HRS), hydrogen peroxide scavenging (HPS), and superoxide anion radical scavenging (SARS) of all synthesized compounds were determined. It was established that the results of HRS-, HPS-, and SARS-CUPRAC methods for three compounds are in accordance with TEAC-CUPRAC assay data.Graphical abstract

Crystal Structures of 4-Methyl-1-(3,4,4-trichloro-1-cyclohexylsulfanyl-2-nitro-buta-1,3-dienyl) Piperidine and 4-(3,4,4-Trichloro-1-decylsulfanyl-2-nitro-buta-1,3-dienyl) Morpholine and Spectroscopic Properties

ABSTRACT 4-Methyl-1-(3,4,4-trichloro-1-cyclohexylsulfanyl-2-nitro-buta-1,3-dienyl) piperidine (2a) and 4-(3,4,4-trichloro-1-decylsulfanyl-2-nitro-buta-1,3-dienyl) morpholine (3b) were synthesized, and their crystal structures were determined. The compound 2a is monoclinic, with space group P21/n, a = 13.2874(8), b = 9.7584(4), c = 15.9479(9) Å, β = 109.110(3)°. V = 1953.91(18) Å3, Z = 4. The cyclohexyl and piperidine rings adopt chair conformation. The compound 3b is monoclinic, with space group P 1 21/c 1, a = 15.7741(3), b = 8.9335(10), c = 16.7775(4) Å, β = 100.7382(13)°. V = 2322.85(8)Å3, Z = 4. The morpholine ring is in a chair conformation. The butadiene unit assumed a configuration close to cissoid in both structures, and their spectroscopic properties were investigated.

Crystal Structures of Tetrakis‐(4‐chlorophenylthio)‐butatriene and Tetrakis‐(tert‐butylthio)‐butatriene

Abstract Tetrakis‐(4‐chlorophenylthio)‐butatriene (3a) and tetrakis‐(tert‐butylthio)‐butatriene (3b) were synthesized, and their crystal structures were determined. The compound 3a is monoclinic, space group P21/c, a=6.9785(8), b=8.6803(9), c=22.884(2) Å, β=93.887(6)o, V=1383.0(3) Å3, Z=2. The compound 3b is monoclinic, space group P21/n, a=11.0615(6), b=10.8507(4), c=11.2717(6) Å, β =116.427(2)o, V=1211.5(1) Å3, Z=4. The title compounds 3a and 3b reside on an inversion center so that only half of the molecule is crystallographically unique. Both compounds are not planar. The crystal structures of 3a and 3b have cumulated double bonds. The C7–C8–C8i and C5–C6–C6i angles that show the linearity in both structures, respectively, are 176.4(3)° in 3a and 175.6(2)° in 3b.

Synthesis and Characterization of Nitrogen and Sulfur Containing 1,4-Naphthoquinones

Abstract New N,S-disubstituted naphthoquinones were synthesized by reactions of S- and N-nucleophiles with 2,3-dichloro-1,4-naphthoquinone. 2-(Hexadecylthio)-3-(phenylamino)-naphthalene-1,4-dione 5a was synthesized by reaction of 2-chloro-3-(phenylamino)-naphthalene-1,4-dione 3a with hexadecanethiol 4a. The structures of the new synthesized naphthoquinone derivatives were determined by micro analyses and spectroscopic methods (FT-IR, 1H NMR, 13C NMR, MS, and UV/Vis.). Photo- and electrochemical properties of selected compounds were investigated by using fluorescence spectroscopy and the cyclovoltammetry method. GRAPHICAL ABSTRACT

2,4,4-Tris(benzyl-sulfan-yl)-1,1-dichloro-3-nitro-buta-1,3-diene.

In the title compound, C25H21Cl2NO2S3, the three phenyl rings are inclined to each other at dihedral angles of 68.4 (1), 79.5 (1) and 37.0 (1)°.

Synthesis and investigation of antimicrobial and antioxidant activity of anthraquinonylhydrazones

The new anthraquinonylhydrazones were obtained by the interaction of 9,10-dioxoanthracene-1-diazonium sulfates with a number of α- and β-carbonyl-containing compounds under modified conditions of the Japp–Klingemann reaction, and a probable mechanism of the formation has been proposed. It was found that hydrazones, unsaturated in the second position of the anthraquinone ring, containing acetyl or ethoxycarbonyl moieties in the ylidene part of the molecule, are capable of eliminating these fragments. It has been experimentally established that hydrazones, free rotation around the N=C bond of which is possible, exist as one isomer due to the presence of an intramolecular hydrogen bond in the molecule. The anthraquinonylhydrazone of dimedone with action against the bacteria strains of Staphylococcus aureus 209-P, Mycobacterium luteum B-917, and fungus Candida tenuis VKM Y-70 was found. The hydrazones of dimedone and barbituric acid with a higher trolox equivalent antioxidant coefficients of antioxidant action were found using CUPRAC assay. In addition, the hydrazones of dimedone and barbituric acid exhibited better activity against catalase enzyme. Correlations between the structure of the synthesized hydrazones and their antioxidant activity have been defined.Graphical abstract