Synthesis and Characterization of a “Turn-On” photoCORM for Trackable CO Delivery to Biological Targets

Abstract

A designed photoactive CO releasing molecule (photoCORM), namely, fac-[MnBr(CO)3(pbt)] (1, pbt = 2-(2-pyridyl)benzothiazole), promotes CO-induced death of MDA-MB-231 human breast cancer cells upon illumination with broadband visible light. The CO release from this photoCORM can be tracked by rise in fluorescence within the cellular matrix due to deligation of the pbt ligand. The results of this study suggest the potential of 1 in eradication of cancer cells through CO delivery.

Light-triggered CO delivery by a water-soluble and biocompatible manganese photoCORM

“…Since electronic absorption spectroscopy of the photolyzed solution indicated deligation of pyTAm from complex 2 , the similarity in these two EPR patterns suggested a solvated Mn(II) species in the photolyzed product along with the free ligand (pyTAm). Collectively the photo behavior of 2 is consistent with our previous findings 17,22 as well with other water-soluble manganese photoCORMs reported recently. 34 …”

“…17–19 However, development of a physiologically acceptable photoCORM still remains as a tantalizing challenge. We have been engaged in systematic isolation of various group 7 and 8 metal-based photoCORMs on the basis of few design principles.…”

Click with a boronic acid handle: a neighboring group-assisted click reaction that allows ready secondary functionalization

“…28 More recently, benzothiazole analogs have been utilized in studying the biologically important and naturally occurring gasotransmitter molecules, hydrogen sulfide 29 and carbon monoxide. 30 Consequently, the new chemistry described here has a wealth of synthetic applications as well.…”

PhotoCORMs: CO release moves into the visible

“…76 Whilst both complexes of formula fac-M (38) experimental data was combined with TD-DFT results to show that UV-visible spectra alone are not predictive of good CO release: it is the nature of the absorbing orbitals which is important, as energy must be transferred to CO-bond cleavage. Most recently, this work has been extended to the ligands 40 and 41 (Fig.…”