{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T19:01:04Z","timestamp":1782327664811,"version":"3.54.5"},"reference-count":45,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2025,9,10]],"date-time":"2025-09-10T00:00:00Z","timestamp":1757462400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["NRF-2023R1A2C2004993"],"award-info":[{"award-number":["NRF-2023R1A2C2004993"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Dinitrosyl iron complexes (DNICs) are the most abundant nitric oxide (NO) metabolites in NO-producing cells and can be used as a platform for photochemical vehicles for NO donors. However, not much is known about the photochemical dynamics of DNICs. This study investigates the photoexcitation dynamics of a mononuclear DNIC ligated with 2-mercaptoethanol, [(HOCH2CH2S)2Fe(NO)2]\u2212, in D2O solution through femtosecond infrared spectroscopy. Approximately 70% of the excited [(HOCH2CH2S)2Fe(NO)2]\u2212 at 400 nm relaxes back to the ground state with a time constant of 270 ps, and the remaining dissociates NO\u2212 with a time constant of 630 ps. The resulting mononitrosyl iron complex, [(HOCH2CH2S)2Fe(NO)(D2O)2], formed by a rapid coordination of D2O molecule to the nascent photoproduct, [(HOCH2CH2S)2Fe(NO)], reacts with the abundant thiolate, HOCH2CH2S\u2212, in solution, producing [(HOCH2CH2S)3Fe(NO)]\u2212 with a rate constant of 1.3 \u00d7 107 M\u22121s\u22121. The detailed photochemical dynamics described herein lays the groundwork for the development of NO\u2212 donors using DNICs with controlled and tunable photoreactivity for potential therapeutic applications.<\/jats:p>","DOI":"10.3390\/ijms26188835","type":"journal-article","created":{"date-parts":[[2025,9,10]],"date-time":"2025-09-10T15:39:23Z","timestamp":1757518763000},"page":"8835","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Ultrafast Photochemical Dynamics of Dinitrosyl Iron Complexes Investigated by Femtosecond Time-Resolved Infrared Spectroscopy"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4105-3750","authenticated-orcid":false,"given":"Hojeong","family":"Yoon","sequence":"first","affiliation":[{"name":"Department of Chemistry and Chemistry Institute for Functional Materials, Pusan National University, Busan 46241, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2418-8020","authenticated-orcid":false,"given":"Juhyang","family":"Shin","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Chemistry Institute for Functional Materials, Pusan National University, Busan 46241, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1826-9943","authenticated-orcid":false,"given":"Seongchul","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Chemistry Institute for Functional Materials, Pusan National University, Busan 46241, Republic of Korea"},{"name":"Korea Institute for Future Earth, Pusan National University, Busan 46241, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8920-3458","authenticated-orcid":false,"given":"Manho","family":"Lim","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Chemistry Institute for Functional Materials, Pusan National University, Busan 46241, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"359","DOI":"10.1007\/s00775-006-0084-y","article-title":"Iron nitrosyl complexes as models for biological nitric oxide transfer reagents","volume":"11","author":"Chiang","year":"2006","journal-title":"J. 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