Methanol → 6-N-(4-Monomethoxytrityl)-9-(3,5-di-O-benzoyl-2-deoxy-beta-L-threo-pentofuranosyl)adenine

Temperature

60 °C

To a solution of compound 4 (0.88 g, 1.92 mmol) in dry pyridine (40 mL) was added 4-monomethoxytrityl chloride (1.18 g, 3.84 mmol). The mixture was stirred at 60° C. for 24 h. After addition of methanol (5 mL), the solution was concentrated to dryness, the residue was dissolved in dichloromethane (50 mL) and washed successively with water (30 mL), aqueous saturated NaHCO3 (30 mL) and water (30 mL). The organic layer was dried, filtered, concentrated and co-evaporated with toluene to give pure 5 (1.01 g, 72%) as a foam: 1H NMR (CDCl3): δ 2.9-3.0 (m, 2H, H-2′ and H-2″), 3.62 (s, 3H, OCH3), 4.6-4.8 (m, 3H, H-4′, H-5′ and H-5″), 5.85 (pt, 1H, H-3′), 6.44 (dd, 1H, H-1′, J1′,2′=3.1 Hz, J1′,2″=7.3 Hz), 6.9 (br s, 1H, NH-6), 6.7-6.8 and 7.2-7.4 (2m, 24H, 2 benzoyls and MMTr), 7.97 and 8.13 (2s, 2H, H-2 and H-8); ms: matrix G/T, (FAB+) m/z 732 [M+H]+, (FAB−) m/z 730 [M−H]−; UV (95% ethanol): λmax 274 nm (ε 12100), 225 nm (ε 24200), λmin 250 nm (ε 5900); [α]D20=−16 (c 1.12, DMSO).

1. concentrationthe solution was concentrated to dryness
2. dissolutionthe residue was dissolved in dichloromethane (50 mL)
3. washwashed successively with water (30 mL), aqueous saturated NaHCO3 (30 mL) and water (30 mL)
4. customThe organic layer was dried
5. filtrationfiltered
6. concentrationconcentrated

ORD record

ord-a74fb9960cc84828a6e183f274e26087

Source dataset

uspto-grants-2016_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09290533B2