Duplex Stability of Oligonucleotides Containing 7-Substituted 7-Deaza- and 8-Aza-7-Deazapurine Nucleosides

Abstract

The synthesis of 7-substituted 7-deaza- and 8-aza-7-deazapurine 2′-deoxyribonucleosides, their incorporation into oligonucleotides, and the stability of corresponding duplexes is described.

Notes

5a: ¹H-NMR (d₆-DMSO): δ, 2.30 (1H, m, H-2′), 2.84 (1H, m, H-2′), 3.06 (2H, m, 2H-5′), 3.76, 3.78 (6H,2s, NMe₂), 3.71, 3.72 (6H, 2s, 2 OMe), 3.95 (1H, m, H-4′), 4.51 (1H, m, H-3′), 5.30 (1H, d, 3′-OH), 6.58 (1H, t, H-1′), 6.76–7.37 (13H, m, arom. H), 8.47 (1H, s, H-6), 8.98 (1H, s, CH)

¹H-NMR (d₆-DMSO): δ, 1.74 (ZH, m, CH₂), 2.23 (1H, m, H-2′), 2.46 - 2.48 (3H, m, CH₂, H-2′), 3.11, 3.15 (6H, 2s, NMe₂), 3.13 (2H, m, 2H-5′), 3.33 (2H, m, CH₂), 3.74 (6H, s, OCH₃), 3.91 (1H, m, H-4′), 4.34 (1H, m, H-3′), 5.29 (1H, d, 3′-OH), 6.54 (1H, t, H-1′), 6.82–7.36 (13H, m, arom. H), 7.56 (1H, s, H-6), 8.29 (1H, s, H-2), 8.73 (1H, s, CH), 9.43 (1H, s, NH)

¹H-NMR (d₆-DMSO): δ, 1.12 (6H, m, 2 Me), 1.74 (2H, m, CH₂), 2.23 (1H, m, H-2′), 2.41 (2H, m, CH₂), 2.76 (1H, m, CH), 3.11 (2H, m, 2H-5′), 3.30 (2H, m, CH₂), 3.72 (6H, s, 2 OCH₃), 3.90 (1H, m, H-4′), 4.32 (1H, m, H-3′), 5.27 (1H, d, 3′-OH), 6.39 (1H, t, H-1′), 6.85–7.37 (14H, m, arom.H, H-6), 9.47 (1H, t, NHCOCF₃), 11,53 (1H, s, NH), 11.81 (1H; s, NH).