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1. Folding-Assisted Peptide Disulfide Formation and Dimerization

   https://doi.org/10.1021/acschembio.3c00268  

   Victorio, Clara G; Sawyer, Nicholas (June 2023, ACS Chemical Biology)
2. Tethered Alkylidenes for REMP from Carbon Disulfide Cleavage

   https://doi.org/10.1021/acs.inorgchem.4c01522  

   Jakhar, Vineet K; Shen, Yu-Hsuan; Yadav, Rinku; Nadif, Soufiane S; Ghiviriga, Ion; Abboud, Khalil A; Lester, Daniel W; Veige, Adam S (July 2024, Inorganic Chemistry)

   Reactions between tungsten alkylidyne [tBuOCO]W≡CtBu(THF)2 1 and sulfur containing small molecules are reported. Complex 1 reacts with CS2 to produce intermediate η2 bound CS2 complex [O2C(tBuC═)W(η2-(S,C)-CS2)(THF)] 8. Heating complex 8 provides a mixture of a monomeric tungsten sulfido complex 9 and a dimeric complex 10 in a 4:1 ratio, respectively. Heating the mixture does not perturb the ratio. Addition of excess THF in a solution of 9 and 10 (4:1) converts 10 to 9 (>96%) with concomitant loss of (CS)x. Both 9 and 10 can be selectively crystallized from the mixture. An alternative synthesis of exclusively monomeric 9 involves the reaction between 1 and PhNCS. Demonstrating ring expansion metathesis polymerization (REMP), tethered tungsten alkylidene 8 polymerizes norbornene to produce cis-selective syndiotactic cyclic polynorbornene (c-poly(NBE)). 

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3. Radical-disulfide exchange in thiol–ene–disulfidation polymerizations

   https://doi.org/10.1039/d2py00172a  

   Bongiardina, Nicholas J.; Soars, Shafer M.; Podgorski, Maciej; Bowman, Christopher N. (July 2022, Polymer Chemistry)

   Radical-disulfide exchange reactions in thiol–ene–disulfide networks were evaluated for several structurally distinct thiol and disulfide containing monomers. A new dimercaptopropionate disulfide monomer was introduced to assess how different disulfide moieties affect the exchange process and how the dynamic exchange impacts polymerization. The stress relaxation rate for the disulfides studied herein was highly tunable over a narrow range of network compositions, ranging from 50% relaxation over 10 minutes to complete relaxation over a few seconds, by changing the thiol–disulfide stoichiometry or the disulfide type in the monomer. The thiol/disulfide monomer pair was shown to have significant influence on how radical-disulfide exchange impacts the polymerization rate, where pairing a more stable radical forming thiol ( e.g. an alkyl thiol) with a less stable radical-forming disulfide ( e.g. a dithioglycolate disulfide) reduces the rate of the thiol–ene reaction by over an order of magnitude compared to the case where those two radicals are of the same type. The variations in rates of radical-disulfide exchange with dithioglycolate and dimercaptopropionate disulfides had a significant impact on stress relaxation and polymerization stress, where the stress due to polymerization for the final dimercaptopropionate network was about 20% of the stress in the equivalent dithiogylcolate network under the same conditions. These studies provide a fundamental understanding of this polymerization scheme and enable its implementation in materials design. 

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4. Photochemically Induced Phase Change in Monolayer Molybdenum Disulfide

   https://doi.org/10.3389/fchem.2019.00442  

   Byrley, Peter; Liu, Ming; Yan, Ruoxue (June 2019, Frontiers in Chemistry)
5. Disulfide-Modified Mesoporous Silica Nanoparticles for Biomedical Applications

   https://doi.org/10.3390/cryst13071067  

   Venedicto, Melissa; Carrier, Jake; Na, Ha; Chang, Chen-Yu; Radu, Daniela R.; Lai, Cheng-Yu (July 2023, Crystals)

   Mesoporous silica nanoparticles (MSNs) are highly porous carriers used in drug and gene delivery research for biomedical applications due to their high surface area, narrow particle size distribution, and low toxicity. Incorporating disulfide (SS) bonds into the walls of MSNs (MSN-SSs) offers a dual pathway for drug release due to the pore delivery and collapsing porous structure after cellular engulfment. This study explores the effect of embedding disulfide bonds into MSNs through various structural and biological characterization methods. Raman spectroscopy is employed to detect the SS bonds, SEM and TEM for morphology analyses, and a BET analysis to determine the required amount of SSs for achieving the largest surface area. The MSN-SSs are further loaded with doxorubicin, an anticancer drug, to assess drug release behavior under various pH conditions. The MSN-SS system demonstrated an efficient pH-responsive drug release, with over 65% of doxorubicin released under acidic conditions and over 15% released under neutral conditions. Cleaving the SS bonds using dithiothreitol increased the release to 94% in acidic conditions and 46% in neutral conditions. Biocompatibility studies were conducted using cancer cells to validate the engulfment of the nanoparticle. These results demonstrate that MSN-SS is a feasible nanocarrier for controlled-release drug delivery. 

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