eprintid: 10184728 rev_number: 12 eprint_status: archive userid: 699 dir: disk0/10/18/47/28 datestamp: 2024-02-29 10:12:48 lastmod: 2024-02-29 10:12:48 status_changed: 2024-02-29 10:12:48 type: thesis metadata_visibility: show sword_depositor: 699 creators_name: Rochet, Léa Nicole Christiane title: Exploiting the pyridazinedione scaffold to create novel bioconjugates, especially in the areas of reversible thiol modification and chemically constructed bispecifics ispublished: unpub divisions: UCL divisions: B04 divisions: C06 divisions: F56 note: Copyright © The Author 2022. Original content in this thesis is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) Licence (https://creativecommons.org/licenses/by-nc/4.0/). Any third-party copyright material present remains the property of its respective owner(s) and is licensed under its existing terms. Access may initially be restricted at the author’s request. abstract: Over the past decades, the development of protein modification through cysteines, due their low abundance and high nucleophilicity, has enabled many advances in medicinal, imaging or diagnostics fields. In particular, their modification is of high interest for proteomic purposes, to inhibit the function of some proteins, or for the incorporation of any payload into a protein. On one hand, the development of probes/drugs for the targeting of cysteines in vivo has been clouded by their side, cytotoxic, effects. To overcome this, tools for the reversible modification of cysteines have been investigated. However, only a limited number of reagents have been reported so far and most of them suffer from stability issues, a lack of modularity and/or poor tunability. In this work, a library of tuneable nonbromo pyridazinediones (nonBr PD), as Michael acceptors, has been developed for their ability to react reversibly with cysteines. A correlation between the electrophilicity of the PDs and the Michael-addition/retro-Michael reaction rates was found. Those rates were reproducible onto a range of different cysteines, and the use of PD was exemplified on proteins/materials. Further investigations to understand the reactivity of those reagents led to the development of novel, improved, disulfide rebridging reagents. On the other hand, the focus has been on the development of chemical strategies for the stable modification of cysteine residues, applied to the generation of novel therapeutics, such as Antibody-Drug Conjugates (ADC) or bispecific formats for the treatment of cancer. Dibromo pyridazinediones (diBr PDs) scaffold have been previously reported for the homogeneous modification of disulfide bonds. Building on the works developed with diBr PDs and in collaboration with Wageningen University of Research and Queen’s University of Belfast, two novel bispecific formats based on site-selective modification strategies were developed and one of them was successfully tested in cell-based bioassays as a T-cell engager bispecific. date: 2024-01-28 date_type: published oa_status: green full_text_type: other thesis_class: doctoral_open thesis_award: Ph.D language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 2136988 lyricists_name: Rochet, Léa lyricists_id: LROCH43 actors_name: Rochet, Léa actors_id: LROCH43 actors_role: owner full_text_status: public pages: 549 institution: UCL (University College London) department: Chemistry thesis_type: Doctoral citation: Rochet, Léa Nicole Christiane; (2024) Exploiting the pyridazinedione scaffold to create novel bioconjugates, especially in the areas of reversible thiol modification and chemically constructed bispecifics. Doctoral thesis (Ph.D), UCL (University College London). Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10184728/2/Thesis_Lea_Rochet_deposit.pdf