Self-amplified depolymerization of oligo(thiourethanes) for the release of COS/H₂S

Herein we report the self-amplified depolymerization of an aryl oligo(thiourethane) (OTU) for the release of COS/H₂S. The OTU was synthesized via polyaddition of 4-isothiocyanatobenzyl alcohol and end-capped with an aryl azide. The aryl azide chain-end was reduced by tris(2-carboxyethyl)phosphine or H₂S to the corresponding aniline, resulting in depolymerization (i.e., self-immolation) and the release of COS/H₂S. Depolymerization was monitored by 1H NMR and UV-Vis spectroscopy, and the released COS was converted into H₂S by the ubiquitous enzyme carbonic anhydrase in aqueous media, generating an amplified response.