- Diastereoselective oxidative addition of cyclic thiosulfinates to platinum(O) compounds: Chiral platinum(II) complexes with sulfenato ligands Crystal structures of S(O)-CH2-CH(OAc)-CH(OAc)-CH2-S and dppePt[S(O)-(CH2)4-S] Part 16. Metal complexes of functionalized sulfur-containing ligands
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The oxidative addition reactions of the racemic thiosulfinates S-(CH2)4-S(O) (1) and S-CH2-(C6H4)-CH2-S(O) (4) with dppePt(η2-C2H4) (6) led to the 1-sulfenato-4-thiolato platinum(II) complexes dppePt[S(O)-(CH2)4-S] (8) and dppePt[S(O)-CH2-(C6H4)-CH2-S] (9); the crystal structure of complex 8 was determined. The oxidative addition of the racemic thiosulfinate S-CH2-CH(OAc)-CH(OAc)-CH2-SO) [(R*SO, R*, R*)-2] to (Ph3P)2Pt(η2-C2H4) (5) gave two diastereoisomers of compound (Ph3P)2Pt[S(O)-CH2-CH(OAc)-CH(OAc)-CH 2-S] (10) in a ratio 1:1. The thiosulfinates [(R*SO, R*,R*)-2] and [(R*SO,R*,S*)-3] reacted with [(R, R-diop)]Pt(η2-C2H4) (7) to yield four diastereoisomers each of the complexes [(R,R-diop)]Pt[S(O)-CH2-CH(OAc)-CH(OAc)-CH2-S] (11) and 12 in a ratio 100:100:1:1 and 10:10:1:1, respectively. [(R*SO, R*, S*)-3] was characterized structurally. Treatment of the mixture of diastereoisomers of complex 11 with two equivalents of dppe gave only one diastereoisomer of complex dppePt[S(O)-CH2-CH(OAc)-CH(OAc)-CH2-S] (13).
- Wünsch, Ralf,Bosl, Gabriele,Robl, Christian,Weigand, Wolfgang
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- HETEROCYCLIC-DITHIOL CLICK CHEMISTRY
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Disclosed are polymers, methods of making polymers, and compositions, focused on cross-linking heterocycles comprising a moiety of Formula I with thiols and thiolates.
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Paragraph 00180; 00181
(2019/02/02)
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- Cyclic Thiosulfinates and Cyclic Disulfides Selectively Cross-Link Thiols while Avoiding Modification of Lone Thiols
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This work addresses the need for chemical tools that can selectively form cross-links. Contemporary thiol-selective cross-linkers, for example, modify all accessible thiols, but only form cross-links between a subset. The resulting terminal "dead-end" modifications of lone thiols are toxic, confound cross-linking-based studies of macromolecular structure, and are an undesired, and currently unavoidable, byproduct in polymer synthesis. Using the thiol pair of Cu/Zn-superoxide dismutase (SOD1), we demonstrated that cyclic disulfides, including the drug/nutritional supplement lipoic acid, efficiently cross-linked thiol pairs but avoided dead-end modifications. Thiolate-directed nucleophilic attack upon the cyclic disulfide resulted in thiol-disulfide exchange and ring cleavage. The resulting disulfide-tethered terminal thiolate moiety either directed the reverse reaction, releasing the cyclic disulfide, or participated in oxidative disulfide (cross-link) formation. We hypothesized, and confirmed with density functional theory (DFT) calculations, that mono-S-oxo derivatives of cyclic disulfides formed a terminal sulfenic acid upon ring cleavage that obviated the previously rate-limiting step, thiol oxidation, and accelerated the new rate-determining step, ring cleavage. Our calculations suggest that the origin of accelerated ring cleavage is improved frontier molecular orbital overlap in the thiolate-disulfide interchange transition. Five- to seven-membered cyclic thiosulfinates were synthesized and efficiently cross-linked up to 104-fold faster than their cyclic disulfide precursors; functioned in the presence of biological concentrations of glutathione; and acted as cell-permeable, potent, tolerable, intracellular cross-linkers. This new class of thiol cross-linkers exhibited click-like attributes including, high yields driven by the enthalpies of disulfide and water formation, orthogonality with common functional groups, water-compatibility, and ring strain-dependence.
- Donnelly, Daniel P.,Dowgiallo, Matthew G.,Salisbury, Joseph P.,Aluri, Krishna C.,Iyengar, Suhasini,Chaudhari, Meenal,Mathew, Merlit,Miele, Isabella,Auclair, Jared R.,Lopez, Steven A.,Manetsch, Roman,Agar, Jeffrey N.
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supporting information
p. 7377 - 7380
(2018/06/11)
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- Enzyme-catalysed oxidation of 1,2-disulfides to yield chiral thiosulfinate, sulfoxide and cis-dihydrodiol metabolites
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Enantioenriched and enantiopure thiosulfinates were obtained by asymmetric sulfoxidation of cyclic 1,2-disulfides, using chemical and enzymatic (peroxidase, monooxygenase, dioxygenase) oxidation methods and chiral stationary phase HPLC resolution of racemic thiosulfinates. Enantiomeric excess values, absolute configurations and configurational stabilities of chiral thiosulfinates were determined. Methyl phenyl sulfoxide, benzo[c]thiophene cis-4,5-dihydrodiol and 1,3-dihydrobenzo[c]thiophene derivatives were among unexpected types of metabolites isolated, when acyclic and cyclic 1,2-disulfide were used as substrates for Pseudomonas putida strains. Possible biosynthetic pathways are presented for the production of metabolites from 1,4-dihydrobenzo-2,3-dithiane, including a novel cis-dihydrodiol metabolite that was also derived from benzo[c]thiophene and 1,3-dihydrobenzo[c]thiophene.
- Boyd, Derek R.,Sharma, Narain D.,Shepherd, Steven D.,Allenmark, Stig G.,Allen, Christopher C. R.
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p. 27607 - 27619
(2014/07/21)
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- Photooxidations of Sulfenic Acid Derivatives 2. A Remarkable Solvent Effect on the Reactions of Singlet Oxygen with Disulfides.
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Photooxidations of a series of 9 disulfides reveal that the thiosulfinate/thiosulfonate product ratios can be dramatically influenced by the nature of the solvent.The unique ability of methanol to influence this ratio is attributed to nucleophilic addition to a thiopersulfoxide intermediate.
- Clennan, Edward L.,Wang, Dongyi,Zhang, Houwen,Clifton, Christine H.
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p. 4723 - 4726
(2007/10/02)
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- A New Acid-catalysed Rearrangement of Thiosulphinates to α-Acetylthio-sulphoxides in Acetic Anhydride
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Some thiosulphinates with at least one proton on the carbon adjacent to the sulphenyl sulphur react with acetic anhydride containing acetic acid to afford the corresponding α-acetylthio-sulphoxides.The mechanism of this reaction was studied using thiosulphinates labelled with (2)H, (13)C, and (18)O.These tracer experiments demonstrated that the reaction proceeds via an initial Ei reaction to form the corresponding sulphenic acid ant thioaldehyde followed by recombination in which the sulphur atom of the sulphenic acid adds to the carbon atom of the thioaldehyde, eventually affording the rearranged α-acetylthio-sulphoxide.The formation of the sulphenic acid was confirmed by trapping it with methyl acrylate.The mechanism of the reaction is discussed.
- Furukawa, Naomichi,Morishita, Tsuyoshi,Akasaka, Takeshi,Oae, Shigeru
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p. 432 - 440
(2007/10/02)
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