Water → 3alpha-N-methyl-dihydronicotinoyloxy-5alpha-pregnan-20-one

Temperatur

0 °C

To an ice cold solution of the 3α-N-methyl-nicotinoyloxy-5α-pregnan-20-one iodide salt (1.01 g, 562 g/m, 1.8 mmol) in 150 mL of aqueous methanol (100 ml methanol and 50 ml water, deaerated) was added sodium bicarbonate (620 mg, 84 g/m, 7.4 mmol) and sodium dithionite (1.3 g, 174 g/m, 7.4 mmol). This mixture was stirred at 0° C. for 1 h. The reaction mixture was poured into 500 mL of water and extracted several times with chloroform. The combined organic layers were washed with potassium carbonate and concentrated. The crude product was filtered through a bed of silica gel using hexane/ethyl acetate (5:1) elution. The product was recovered in the initial fractions to give 180 mg (439 g/m, 0.4 mmol, 22%).

1. extractionextracted several times with chloroform
2. washThe combined organic layers were washed with potassium carbonate
3. concentrationconcentrated
4. filtrationThe crude product was filtered through a bed of silica gel
5. washhexane/ethyl acetate (5:1) elution
6. customThe product was recovered in the initial fractions
7. customto give 180 mg (439 g/m, 0.4 mmol, 22%)

ORD-Eintrag

ord-ee02f86a0d724b7c9990ebb3d758804e

Quelldatensatz

uspto-grants-1993_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05232917