Synthesis of Nucleoside Derivatives of <i>N</i>-Acetyl-7-nitroindoline, Their Incorporation into the DNA Oligomer, and Evaluation of Their Photoreactivity in the DNA/RNA Duplex

Abstract

N-Acetyl-7-nitroindoline has a characteristic reaction in that its acetyl group is photo-activated to acetylate amines to form amides. In this study, the N-acetyl-7-nitroindoline part was connected to the 2′-deoxyribose part at the 3-or 5-position or to a glycerol unit at the 3-position through an ethylene linker (1, 2, and 3, respectively). They were incorporated into the oligodeoxynucleotides, and their photo-reactivities toward the complementary RNA were evaluated. The acetyl group of 1 was photo-activated to form the deacelylated nitroso derivative without affecting the RNA strand. The photoreaction with 2 suggested acetylation of the RNA strand. In contrast, compound 3 formed the photo-cross-linked adduct with the RNA. These results have shown the potential application of N-acetyl-7-nitroindoline unit in aqueous solutions.

Synthesis and Photoreactivity of 7-Nitroindoline-S-thiocarbamates

“…21,22 Recently, nucleoside derivatives of N-acetyl-7-nitroindoline were incorporated into a DNA oligomer, and their photoreactivity within a DNA/RNA duplex was studied. 23 Remarkably, the opposite strand was acetylated in an aqueous reaction medium. Known photoreactive 7-nitroindolines with N-carbonyl-groups other than amides are carbamate and urea derivatives.…”

“…An N -acyl-7-nitroindoline-based photolabile linker was developed for solid-phase synthesis and was used for the photoinduced release of linear and cyclic amides from the solid support by intra- and intermolecular transamidation . We have synthesized a similar 7-nitroindoline-based linker suitable for solid-phase peptide synthesis, which proved useful for the photochemical synthesis of peptide thioesters and hydrazides. , Thin films of amino acid and peptide derivatives of 7-nitroindolines have also been used for micropatterning by two-photon photolysis using femtosecond laser light at 710 nm. , Recently, nucleoside derivatives of N -acetyl-7-nitroindoline were incorporated into a DNA oligomer, and their photoreactivity within a DNA/RNA duplex was studied . Remarkably, the opposite strand was acetylated in an aqueous reaction medium.…”