Reacción #40594

Ecuación de reacción

8a

(2S,4aS,6aR,7R,9S,10aS,10bR)-9-(hydroxy)-2-(3-furanyl)dodecahydro-6a,10b-dimethyl-4,10-dioxo-2H-naphtho[2,1-c]pyran-7-carboxylic acid methyl ester

methanesulfonyl chloride

NEt3

→

white solid

Rendimiento 32.0%

(2S,4aR,6aR,7R,9S,10aS,10bR)-9-(methanesulfonyloxy)-2-(3-furanyl)-dodecahydro-6a,10b-dimethyl-4,10-dioxo-2H-naphtho[2,1-c]pyran-7-carboxylic acid methyl ester

Rendimiento 32.0%

Disolventes

CH2Cl2

Condiciones de reacción

Tratamiento posterior

1. 1
   Lavadothe mixture was washed with saturated NaHCO3 (20 mL) and saturated NaCl (2×15 mL)
2. 2
   Secadodried (Na2SO4)
3. 3
   OtroThe solvent was removed under reduced pressure
4. 4
   OtroThe resulting crude solid was purified by column chromatography (eluent: ethyl acetate/n-hexanes)

Procedimiento

A solution of 8a (0.05 g, 0.13 mmol), methanesulfonyl chloride (1 mL) and NEt3 (2 mL) in CH2Cl2 (30 mL) was stirred at room temperature overnight and then the mixture was washed with saturated NaHCO3 (20 mL) and saturated NaCl (2×15 mL) and dried (Na2SO4). The solvent was removed under reduced pressure. The resulting crude solid was purified by column chromatography (eluent: ethyl acetate/n-hexanes) to afford 0.02 g (32%) of a white solid, mp 147-150° C.; 1H NMR (CDCl3): δ 1.14 (3H, s, H-19); 1.47 (3H, s, H-20); 1.50-1.70 (3H, m, H-7α,β and H-11β); 1.81 (1H, m, H-6α); 2.11 (1H, dd, J=2.9, 11.3 Hz, H-8); 2.16 (1H, s, H-10); 2.19 (1H, m, H-6β); 2.42 (1H, dd, J=13.2, 13.2 Hz, H-3α); 2.50 (1H, m, H-3β); 2.52 (1H, dd, J=4.8, 13.2 Hz, H-11α); 2.75 (1H, dd, J=3.6, 13.2 Hz, H-4); 3.25 (3H, s, CH3SO2); 3.74 (3H, s, CO2CH3); 5.07 (1H, dd, J=8.0, 12.2 Hz, H-2); 5.55 (1H, dd, J=5.1, 11.7 Hz, H-12); 6.41 (1H, dd, J=0.9, 1.8 Hz, H-14); 7.42 (1H, dd, J=1.8, 1.8 Hz, H-15); 7.45 (1H, br d).

Fuente