反応 #4976

反応方程式

7-hydroxy-2-octadecyl-3H-phenoxazine-3-one

sym-collidine

1-bromo-2,3,4,6-tetra-O-acetyl-α-D-galactopyranoside

→

title compound

2-octadecyl-7-(2,3,4,6-tetra-O-acetyl β-D-galactopyranosyloxy)-3H-phenoxazin-3-one

溶媒

dichloromethane

反応条件

後処理

1. 1
   workup.STIRRINGslowly with stirring
2. 2
   workup.STIRRINGto stir as above for 72 hours
3. 3
   ろ過After this time the reaction mixture is filtered through a pad of diatomaceous earth
4. 4
   洗浄The precipitate is washed with chloroform (5×10 mL)
5. 5
   抽出the combined organic filtrates are extracted with 1M aqueous HCl (1×75 mL), saturated aqueous sodium bicarbonate solution (1×75 mL), 1M sodium thiosulfate (1×75 mL), and water (1×75 mL)
6. 6
   乾燥The organic layer is dried over anhydrous sodium sulfate
7. 7
   ろ過filtered
8. 8
   その他evaporated under reduced pressure
9. 9
   乾燥dried in vacuo to an orange-brown powder (440 mg)

実験手順

A mixture of 7-hydroxy-2-octadecyl-3H-phenoxazine-3-one ("octadecylresorufin) (220 mg, 0.47 mmole), powdered, activated 4Å molecular sieves (0.5 g), sym-collidine (125 μL, 0.95 mmole), and silver carbonate (155 mg, 0.56 mmole) in dry dichloromethane (20 mL) is allowed to stir at room temperature, under an atmosphere of dry nitrogen gas, in the dark for 1 hour. To this mixture is added 1-bromo-2,3,4,6-tetra-O-acetyl-α-D-galactopyranoside (389 mg, 0.95 mmole), slowly with stirring, and the resulting heterogenous solution allowed to stir as above for 72 hours. After this time the reaction mixture is filtered through a pad of diatomaceous earth. The precipitate is washed with chloroform (5×10 mL) and the combined organic filtrates are extracted with 1M aqueous HCl (1×75 mL), saturated aqueous sodium bicarbonate solution (1×75 mL), 1M sodium thiosulfate (1×75 mL), and water (1×75 mL). The organic layer is dried over anhydrous sodium sulfate, filtered, evaporated under reduced pressure, and dried in vacuo to an orange-brown powder (440 mg). An analytical sample of the title compound can be isolated by preparative t.l.c. (20×20 cm SiO2 plate; eluent=9:1 chloroform:ethylacetate) with the bright-orange product eluting at the highest Rf (0.44), (50 mg from 200 mg applied).

出典