Phosphorescent Ruthenium Complexes with a Nitroimidazole Unit that Image Oxygen Fluctuation in Tumor Tissue was written by Son, Aoi;Kawasaki, Atsushi;Hara, Daiki;Ito, Takeo;Tanabe, Kazuhito. And the article was included in Chemistry – A European Journal in 2015.Safety of 2-(2-Nitro-1H-imidazol-1-yl)acetic acid This article mentions the following:
Understanding oxygen fluctuation in a cancerous tumor is important for effective treatment, especially during radiotherapy. Ruthenium complexes bearing a nitroimidazole group report the oxygen status in tumor tissue directly. The nitroimidazole group was known to be accumulated in hypoxic tumor tissues. However, the ruthenium complex showed strong phosphorescence around 600 nm. The emission of ruthenium is quenched instantaneously by mol. oxygen due to energy transfer between triplet states of oxygen and ruthenium complex, but the emission is then recovered by the removal of oxygen. Thus, the authors could observe oxygen fluctuation in tumor tissue in a real-time manner by monitoring the phosphorescence of the ruthenium complex. The versatility of the probe is demonstrated by monitoring oxygen fluctuation in living cells and tumor tissue planted in mice. The ruthenium complex promptly penetrated plasma membrane and accumulated in cells to emit its oxygen-dependent phosphorescence. In vivo experiments revealed that the oxygen level in tumor tissue seems to fluctuate at the sub-minute timescale. In the experiment, the researchers used many compounds, for example, 2-(2-Nitro-1H-imidazol-1-yl)acetic acid (cas: 22813-32-7Safety of 2-(2-Nitro-1H-imidazol-1-yl)acetic acid).
2-(2-Nitro-1H-imidazol-1-yl)acetic acid (cas: 22813-32-7) belongs to imidazole derivatives. 1H-imidazole is an imidazole tautomer which has the migrating hydrogen at position 1. It is a conjugate base of an imidazolium cation. It is a conjugate acid of an imidazolide. It is a tautomer of a 4H-imidazole. The pharmacophore of imidazole exists in bioactive compounds including amino acids, plant growth regulators and therapeutic agents.n increase of the alkyl chain length of the alcohols. Safety of 2-(2-Nitro-1H-imidazol-1-yl)acetic acid
Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem