Nitric oxide is a kind of signaling molecule and is involved in various physiological activities such as immune function, vasodilation and signal transduction. Since nitric oxide is a very unstable substance, it is difficult to control the time to del...
Nitric oxide is a kind of signaling molecule and is involved in various physiological activities such as immune function, vasodilation and signal transduction. Since nitric oxide is a very unstable substance, it is difficult to control the time to deliver it to a desired target. A nitric oxide precursor can be used as a carrier that can control it. Currently, various nitric oxide precursors such as S-nitrosothiols, N-nitrosamines, N-diazeniumdiolates, and metal nitrosyls have been reported, and these nitric oxide precursors are widely known as medicines and therapeutic agents for disease treatment.
In this study, a nitrosoamine derivative of N-N bond with an intermediate bond dissociation energy among nitroso compounds was synthesized. N-nitrosamine [NMA, NEA, NAA, NDPA, NDBA] was synthesized using tert-butyl nitrite and secondary amine having alkyl and aryl substituents. N-nitrosamide [NBA, NMBA] was synthesized using a secondary amine having an amide substituent and tert-butyl nitrite. Basic amino acids were also reacted with tert-butyl nitrite to synthesize N-nitrosated amino acids [NLA, NLL, NLH]. The synthesis of the target compound was confirmed using 1H-NMR and GC-MS,
Nitric oxide generation assay was performed through UV-Vis absorption spectrum through azo-dye production reaction of nitric oxide produced from the synthesized nitric oxide precursor and Griess reagent. In addition, a cytotoxicity assay was performed for nitric oxide generated from nitric oxide precursors through two cytotoxicity tests.
When an aromatic compound is present in the alkyl group next to the secondary amine [NMA, NEA, NAA, NDPA], the synthesis time was short and synthesis was possible even at room temperature. In the case of the NBA, it was not synthesized. It was inferred that the benzene next to the carbonyl group takes electrons and the amine lacks electrons, so the amine protons do not fall off easily, so synthesis is not possible.
In the UV-Vis absorption spectrum through the azo-dye generation reaction using Griess reagent, the time taken to the maximum emission of nitric oxide generated from the nitric oxide precursor was similar at about 90 minutes. However, there was a difference in the release rate up to 90 minutes before.
Through two cytotoxicity tests, a cytotoxicity assay for nitric oxide generated from nitric oxide precursors was performed. In the cell viability assay, nitric oxide precursors diluted to three concentrations (100 mM, 1 mM, 1 μM) were administered to MDA-MB-231 cells. All of the cell groups administered at a concentration of 100 mM died, and at concentrations of 1 mM and 1 μM, cell death was at least twice that of the raw material, but there was no difference as much as a 103 fold difference in concentration. In the Cell MTT assay, a nitric oxide precursor diluted to a concentration of 100 μM was used, and the group using the raw material and the group administered with nitric oxide showed an absorbance difference of about 0.05 at 60 and 90 minutes.