- H2S-Donating trisulfide linkers confer unexpected biological behaviour to poly(ethylene glycol)-cholesteryl conjugates
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Inspired by the properties of the naturally occurring H2S donor, diallyl trisulfide (DATS, extracted from garlic), the biological behaviour of trisulfide-bearing PEG-conjugates was explored. Specifically, three conjugates comprising an mPEG tail and a cholesteryl head were investigated: conjugates bridged by a trisulfide linker (T), a disulfide linker (D) or a carbamate linker (C), and a fourth comprising two mPEG tails bridged by a trisulfide linker (P). H2S testing using both a fluorescent chemical probe in HEK293 cells and an amperometric sensor to monitor release in suspended cells, demonstrated the ability of the trisulfide conjugates,TandP, to release H2S in the presence of cellular thiols. Cytotoxicity and cyto-protective capacity on HEK293 cells showed thatTwas the best tolerated of the conjugates studied, and remarkably more so thanDorC. Moreover, it was noted that application ofTconferred a protective effect to the cells, effectively abolishing the toxicity associated with co-administeredC. The interaction of conjugates and combinations thereof with the cell membrane of HEK cells, as well as ROS generation were also investigated. It was found thatCcaused significant membrane perturbation, correlating with high losses in cell viability and pronounced generation of ROS, especially in the mitochondria.T, however, did not disturb the membrane and was able to mitigate the generation of ROS, especially in the mitochondria. The interplay of the cholesteryl group and H2S donation for conferring cytoprotective effects was clearly demonstrated asPdid not display the same beneficial characteristics asT
- Davis, Thomas P.,Ercole, Francesca,Li, Yuhuan,Quinn, John F.,Whittaker, Michael R.
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- Mechanism of Reduction of Bis(2-hydroxyethyl) Trisulfide by eaq- and .CO2-. Spectrum and Scavenging of RSS. radicals
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Each of the of the reducing radicals eaq., .CO2- and (CH3)2.COH cleaves bis(2-hydroxyethyl) trisulfide in aqueous solution to produce (2-hydroxyethyl)perthiyl (RSS.) radicals and 2-hydroxyethanethiol.The RSS. radical had λmax = 374 nm, εmax = 1630 +/- 50 M-1cm-1, and a second-order rate constant for dimerization 2k12 = (1.4 +/- 0.3)*109 M-1s-1 (2RSS. -> RS4R (12)).It is able to abstract H atoms from dihydroflavin adenine dinucleotide (FH2), but not from formate.Thus, in aqueous solution DRSS-H must be greater than 60 but less than 90 kcal/mol.Although tetrasulfide and thiol are initial products of reduction, secondary thermal reactions occur and produce sulfanes (RSnH) and polysulfides (RSnR).In the early stages of reduction products of n = 2 dominate.However, on prolonged reaction with .CO2- elemental sulfur precipitated, and this is probably formed by elimination from sulfanes with n much larger and in the region of 8.
- Wu, Zhennan,Back, Thomas G.,Ahmad, Rizwan,Yamdagni, Raghav,Armstrong, David A.
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- The biothiol-triggered organotrisulfide-based self-immolative fluorogenic donors of hydrogen sulfide enable lysosomal trafficking
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Biothiol-reactive organotrisulfide-based self-immolative fluorogenic donors of H2S are rationally designed for the efficient monitoring of intracellular and lysosomal trafficking of H2S with a concomitant turn-on fluorescence. The non-toxic nature of the donors with a sustained release of H2S will certainly be helpful for their biomedical applications in the future.
- Mahato, Sulendar K.,Bhattacherjee, Debojit,Bhabak, Krishna P.
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supporting information
p. 7769 - 7772
(2020/07/27)
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- TBAF promoted formation of symmetrical trisulfides
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We have developed a new method for the synthesis of functionalized symmetrical trisulfides based on (5,5-dimethyl-2-thioxo-1,3,2-dioxa-phosphorin- 2-yl)disulfanyl derivatives prepared from readily available 5,5-dimethyl-2-sul- fanyl-2-thioxo-1,3,2-dioxaph
- Lach, Slawomir,Witt, Dariusz
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- Novel and efficient methods for the synthesis of symmetrical trisulfides
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We have developed convenient methods for the synthesis of symmetrical trisulfides under mild conditions in very good yields. The described methods are based on the straightforward preparation of (5,5-dimethyl-2-thioxo-1,3,2- dioxaphosphorin-2-yl)disulfany
- Kertmen, Ahmet,Lach, Slawomir,Rachon, Janusz,Witt, Dariusz
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experimental part
p. 1459 - 1462
(2009/12/08)
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- Production of dithiodiglycol
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In a process to make dithiodiglycol by oxidation of β-mercaptoethanol with sulfur, an improved product is recovered when a 1-10 mol % excess of β-mercaptoethanol is used and hydrogen sulfide is removed by vacuum or nitrogen sparge. A typical product contains 88.1 mol % (92.0 wt %) dithiodiglycol, 2.3 mol % (2.9 wt %) trithiodiglycol and 9.6 mol % (5.1 wt %) unreacted β-mercaptoethanol. Reaction of this product with 35 to 50 wt % solution hydrogen peroxide reduces residual β-mercaptoethanol to less than 0.02 wt % mercaptan. Residual water of about 3.6 wt % after hydrogen peroxide treatment is reduced to less than 1 wt % by vacuum stripping and/or nitrogen sparge or with a wiped film evaporator.
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- Sulfur-atom insertion into the S-S bond - Formation of symmetric trisulfides
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The reaction of triphenylmethanesulfenyl chloride (3a) with acyclic disulfides 4 or 5 give the respective trisulfides 1 or 2 in moderate to good yield and selectivity. A mechanism is advanced to explain the chemistry.
- Hou, Yihua,Abu-Yousef, Imad A.,Doung, Yen,Harpp, David N.
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p. 8607 - 8610
(2007/10/03)
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- Process for the preparation of organic disulphides and polysulphides
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The invention relates to the preparation of organic disulphides and polysulphides by the action of sulphur on a mercaptan or on a polysulphide which is lower in sulphur, in the presence of a basic catalyst. In the process according to the invention, an anion exchange resin is used as catalyst.
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