biostudies-literatureHoerres RU.S. Nuclear Regulatory Commission20688-20698https://www.ebi.ac.uk/biostudies/studies/S-EPMC10732151biostudies-literatureUnknown62(50)Metal complexes with the general formula [M^I(CO)₃(k³-L)]⁺, where M = Re, ¹⁸⁶Re, or ^99mTc and L = 1,4,7-triazacyclononane (TACN), NOTA, or NODAGA chelators, have previously been conjugated to peptide-based biological targeting vectors and investigated as potential theranostic radiopharmaceuticals. The promising results demonstrated by these bioconjugate complexes prompted our exploration of other TACN-based chelators for suitability for (radio)labeling with the [M(CO)₃]⁺ core. In this work, we investigated the role of the TACN pendant arms in complexation of the [M(CO)₃]⁺ core through (radio)labeling of TACN chelators bearing acid, ester, mixed acid-ester, or no pendant functional gInorganic chemistry1,4,7-Triazacyclononane-Based Chelators for the Complexation of [¹⁸⁶Re]Re- and [^99mTc]Tc-Tricarbonyl Cores.PMC1073215131310021M0040Hennkens HMHoerres Rfalse1,4,7-Triazacyclononane-Based Chelators for the Complexation of [¹⁸⁶Re]Re- and [^99mTc]Tc-Tricarbonyl Cores.Metal complexes with the general formula [M^I(CO)₃(k³-L)]⁺, where M = Re, ¹⁸⁶Re, or ^99mTc and L = 1,4,7-triazacyclononane (TACN), NOTA, or NODAGA chelators, have previously been conjugated to peptide-based biological targeting vectors and investigated as potential theranostic radiopharmaceuticals. The promising results demonstrated by these bioconjugate complexes prompted our exploration of other TACN-based chelators for suitability for (radio)labeling with the [M(CO)₃]⁺ core. In this work, we investigated the role of the TACN pendant arms in complexation of the [M(CO)₃]⁺ core through (radio)labeling of TACN chelators bearing acid, ester, mixed acid-ester, or no pendant functional g2023-01-01T00:00:00Z2023 Dec2025-04-18T21:41:58.397Z2025-02-19T02:33:51.172ZS-EPMC107321513768319010.1021/acs.inorgchem.3c01934