Methanesulfonyl chloride → 1-(5-O-Acetyl-2-deoxy-3-O-methanesulfonyl-4-ethynyl-beta-D-threo-pentofuranosyl)thymine

Participants

Reaction Steps

To a pyridine (4 mL) solution of 12 (76 mg, 0.247 mmol) was added methanesulfonyl chloride (57 μL, 0.74 mmol) at 0° C., and the mixture was stirred at room temperature for 16 h. The reaction mixture was partitioned between CHCl3/saturated aqueous NaHCO3 (60 mL×3/20 mL). Silica gel column chromatography (CHCl3/MeOH=100/0-100/1) of the organic layer gave 13 (95.0 mg, 100%) as a foam: 1H NMR (CDCl3)δ1.96 (3H, d, J6,Me=1.2 Hz, Me), 2.16 (3H, s, Ac), 2.38 (1H, ddd, Jgem=16.0 Hz, J1′,2′a=3.5 Hz and J2′a,3′=0.7 Hz, H-2′a), 2.70 (1H, s, ethynyl), 3.11 (1H, s, Ms), 3.19 (1H, ddd, Jgem=16.0 Hz, J1′,2′b=8.4 Hz and J2′b,3′=5.5 Hz, H-2′b), 4.48 (1H, d, Jgem=11.3 Hz, H-5′a), 4.53 (1H, d, Jgem=11.3 Hz, H-5′b), 5.27-5.28 (1H, m, H-3′), 6.52 (1H, dd, J1′,2′a=3.5 Hz and J1′,2′b=8.4 Hz, H-1′), 7.33 (1H, d, J6,Me=1.2 Hz, H-6), 8.86 (1H, brs, NH); FAB-MS m/z 387(M++H).

Provenance & Evidence