Thiol Reactivity Towards Drugs and Radicals: Some Implications in the Radiotherapy and Chemotherapy of Cancer

  • Peter Wardman
Part of the NATO ASI Series book series (NSSA, volume 197)


The papers in these Proceedings attest to the special characteristics imparted by incorporation of sulphur in molecules: a reduction in ionization potential leading to increased ease of oxidation or to increased propensity to function as an electron donor, and a reduction in bond strengths (e.g. S-H compared to C-H) leading to a capacity for radical “repair” of species where C-H bonds have been broken, by hydrogen donation from a thiol. The protective or antioxidant role of thiols, resulting from these two properties, is currently attracting widespread attention. Major interest centres upon the importance of thiols in cancer therapy. Thiols have been recognised as radioprotectors for at least 40 years, and their activity characterised in innumerable model systems both in vitro and in vivo, ranging from pulse radiolysis of dilute aqueous solutions to clinical trials of thiols or pro-drug derivatives.


Pulse Radiolysis Thiyl Radical Benzyl Viologen Good Leaving Group Thiolate Anion 
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Copyright information

© Plenum Press, New York 1990

Authors and Affiliations

  • Peter Wardman
    • 1
  1. 1.Cancer Research Campaign Gray LaboratoryMount Vernon HospitalNorthwood, MiddlesexUK

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