- Universal Anticancer Cu(DTC)2 Discriminates between Thiols and Zinc(II) Thiolates Oxidatively
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Aerobic organisms must rely on abundant intracellular thiols to reductively protect various vital functional units, especially ubiquitous zinc(II) thiolate sites of proteins, from deleterious oxidations resulting from oxidizing environments. Disclosed here is the first well-defined model study for reactions between zinc(II) thiolate complexes and copper(II) complexes. Among all the studied ligands of copper(II), diethyldithiocarbamate (DTC) displays a unique redox-tuning ability that enables copper(II) to resist the reduction by thiols while retaining its ability to oxidize zinc(II) thiolates to form disulfides. This work proves for the first time that it is possible to develop oxidants to discriminate between thiols and zinc(II) thiolates, alluding to a new chemical principle for how oxidants, especially universal anticancer Cu(DTC)2, might circumvent the intracellular reductive defense around certain zinc(II) thiolate sites of proteins to kill malignant cells.
- Xu, Luyan,Xu, Jialin,Zhu, Jingwei,Yao, Zijian,Yu, Na,Deng, Wei,Wang, Yu,Lin, Bo-Lin
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supporting information
p. 6070 - 6073
(2019/03/29)
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- Nucleophilic reactions of phorate and terbufos with reduced sulfur species under anoxic conditions
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The reactions of phorate and terbufos with bisulfide (HS-), polysulfide (Sn2-), thiosulfate (S2O 32-), and thiophenolate (PhS-) were examined in well-defined aqueous solution under anoxic conditions to investigate their role in the degradations of phorate and terbufos. Reactions were monitored at various concentrations of reduced sulfur species to obtain the second-order rate constants. The reactivity of the reduced sulfur species decreased in the order Sn2- > PhS- > HS- > S 2O32-. Hydrolysis products, formaldehyde and diethyl disulfide/di-tert-butyl disulfide, indicated that OH-/H 2O attacked the carbon atom between the two sulfur atoms, the so-called thioacetal carbon, which is very reactive due to the presence of the two neighboring sulfur atoms. The reaction of phorate and terbufos with PhS - was investigated to study the transformation products in the reactions with reduced sulfur species. The transformation products demonstrated that the observed increase in rate constants in the reaction with reduced sulfur species compared to hydrolysis could result from the nucleophilic attack of reduced sulfur species at the α-carbon of the ethoxy group and at the thioacetal carbon atom. The temperature dependence of measured second-order rate constants of the reaction of phorate and terbufos with HS- over 25-50°C was investigated to explore activation parameters, which are not significantly different for phorate and terbufos. All of the observations may imply similar pathways in the degradation of phorate and terbufos in the presence of reduced sulfur species. Slightly higher hydrolysis rates of terbufos and second-order reaction rate constants for the reactions with sulfur species of terbufos compared with those for phorate are observed, which could be attributed to the slightly different substituents.
- Gan, Qiu,Jans, Urs
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p. 3546 - 3554
(2008/02/09)
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- A new sulfenylation reagent, 3-phenylsulfenyl-2-(N- cyanoimino)thiazolidine, and its optically active version
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We have developed a new sulfenylation reagent, 3-phenylsulfenyl-2-(N- cyanoimino)thiazolidine 3, that is readily available and stable upon storage. Compound 3 easily reacts with amines or thiols to give the corresponding sulfenamides or asymmetrical disulfides in excellent yields. It was also found that the α-sulfenylation reaction of carbonyl compounds with 3 proceeds smoothly. Furthermore, optically active 4-diphenylmethyl derivative 4 was synthesized as an asymmetric sulfenylation reagent, which realized 96% e.e. upon α-sulfenylation of a cyclic β-keto ester.
- Tanaka,Azuma,Fang,Uchida,Iwata,Ishida,In,Maezaki
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- Cleavage of S-S bond by nitric oxide (NO) in the presence of oxygen: A disproportionation reaction of two disulfides
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Disulfide bond was cleaved by a catalytic amount of nitric oxide in the presence of oxygen, which was confirmed by experiments employing two symmetrical disulfides. The reaction resulted in the formation of unsymmetrical disulfides in nearly 50% yields. The steric hindrance of alkyl disulfide slowed the reaction rate, and an electron-donating group on the aryl disulfide promoted the reaction. The substituent and S-nitrosothiol effects suggested that the reaction was initialized with an oxidative process by NO+.
- Tsutsumi,Itoh,Ohsawa
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p. 1524 - 1528
(2007/10/03)
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- Disproportionation reaction of disulfides promoted by nitric oxide (NO) in the presence of oxygen
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Two disulfides brought about disproportionation reaction to afford an unsymmetrical disulfide in 50% yield with a catalytic amount of nitric oxide in the presence of oxygen. The reaction proceeded faster when alkyl disulfides were employed for the reaction, and the substituent effects suggested that the reaction commenced with an oxidative process.
- Itoh, Takashi,Tsutsumi, Nozomi,Ohsawa, Akio
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p. 2161 - 2166
(2007/10/03)
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- Some Unusual Properties of Tris(2,6-dimethoxyphenyl)phosphine Sulfide and the Related Compounds
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The title sulfide 3P=S reacted with acids to form a novel mercaptophosphonium salt X, solution thermolysis of which in the absence or presence of triphenylphosphine resulted in the unusual desulfurization to give the tertiary phosphonium salts X. (2,6)3P=S also reacted with alkyl iodides or bromides under mild conditions to give stable (alkylthio)phosphonium salts X (R=Me, Et, n-Bu), which reacted with thiols at room temperature in the presence of a catalytic amount of the tertiary phosphine (2,6)3P to give X and unsymmetrical disulfides.
- Wada, Masanori,Kanzaki, Mitsuyuki,Fujiwara, Masanobu,Kajihara, Kazuhisa,Erabi, Tatsuo
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p. 1782 - 1786
(2007/10/02)
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- Facile Synthesis of Alkylthiophosphonium Salts of Tris(2,6-dimethoxyphenyl)phosphine and Their Reactions with Thiols
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Tris(2,6-dimethoxyphenyl)phosphine sulfide reacted with alkyl iodides or bromides under mild conditions to give stable alkylthiophosphonium salts, which reacted with thiols at room temperature in the presence of a catalytic amount of tris(2,6-dimethoxyphenyl)phosphine to give the tertiary phosphonium salt and unsymmetrical disulfides.
- Wada, Masanori,Kanzaki, Mituyuki,Fujiwara, Masanobu,Kajihara, Kazuhisa,Erabi, Tatsuo
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p. 867 - 870
(2007/10/02)
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- SYNTHESIS OF DISULPHIDES AND TRISULPHIDES via ORGANOSILICON COMPOUNDS
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Silyl sulphides 2a-b smoothly react with thiolsulphinates 1a-c and thiolsulphonates 6a-c to give unsymmetrical disulphides under mild conditions and in very good yields.The "neutral" conditions used allow one to avoid any side reactions and subsequent randomization of the products.When bis(trimethylsilyl)sulphide, 8, is used, symmetrical trisulphides may be obtained under the same experimental conditions.
- Capozzi, Giuseppe,Capperucci, Antonella,Degl'Innocenti, Alessandro,Duce, Rosa Del,Menichetti, Stefano
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p. 421 - 426
(2007/10/02)
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- SILICON IN ORGANOSULPHUR CHEMISTRY. Part 2. SYNTHESIS OF UNSYMMETRICAL DISULPHIDES
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Unsymmetrical aryl- and alkyl-disulphides are prepared from silylsulphides and thiosulphinates or thiosulphonates.Silyl sulphinic esters are also obtained in the reaction of the thiosulphonates.
- Capozzi, Giuseppe,Capperucci, Antonella,Degl'Innocenti, Alessandro,Duce, Rosa Del,Menichetti, Stefano
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p. 2995 - 2998
(2007/10/02)
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- THE SYNTHESIS OF 2-(ALKYLTHIO)- AND 2-(ARYLTHIO)-3-CYANOTHIOPHENES. THE NUCLEOPHILIC DISPLACEMENT OF THE ALKYLSULFINYL GROUP BY THIOLS.
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The nucleophilic substitution of activated 2-(alkylsulfinyl)thiophenes with alkyl- or arylmercaptans gives the corresponding 2-(alkylthio)- or 2-(arylthio)- substituted thiophenes.When thiolate anion is used instead of thiol, sulfoxide reduction is the ma
- Luteijn, J. M.,Dolman, H.,Wals, H. C.
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p. 5921 - 5928
(2007/10/02)
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- 4'-NITROARENESULPHENANILIDES: THEIR USE IN THE SYNTHESIS OF UNSYMMETRICAL DISULPHIDES
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The reaction of 4'-nitroarenesulphenanilides with thiols in the presence of boron trifluoride etherate can provide an effective route to unsymmetrical disulphides.
- Benati, L.,Montevecchi, P. C.,Spagnolo, P.
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p. 1739 - 1742
(2007/10/02)
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