Sulfuric Acid → 4-amino-N-(1,1-dimethylethyl)-3-oxoandrosta-4,6-diene-17beta-carboxamide

Participants

Reaction Conditions

Reaction Steps

A solution of 4,5-epoxy-N-(1,1-dimethylethyl)-3-oxoandrostane-17β-carboxamide (3.0 g, 7.7 mmole) in dimethyl sulfoxide (40 mL), under a nitrogen atmosphere, was placed in an oil bath heated at 60° C. The solution was stirred vigorously as sodium azide (8.11 g, 0.338 mole) was slowly added. After the addition of the azide was complete, concentrated sulfuric acid (0.54 mL) was added. The bath temperature was raised to 100° C. and the reaction was stirred at this temperature for 90 minutes. The reaction was removed from the oil bath and cooled to room temperature and the resulting solid mass was broken up and poured into cold water (550 mL). The mixture was stirred for 30 min and the solids were collected by filtration, washed with water and dried to a yellow solid. The crude product was purified by flash chromatography (hexane-30% ethyl acetate) to give 4-amino-N-(1,1-dimethylethyl)-3-oxoandrosta-4,6-diene-17β-carboxamide as a crystalline, yellow solid (0.90 g, 30%) (aq methanol). IR 3442, 3372, 1662, 1616, 1592, 1570, 1512 cm-1 ; MS (CI) m/z 385 (100%, M+ +1); (EI) m/z 384 (35%, M+), 150 (100%); 1H NMR (CDCl3) δ 0.77 (3H, s, C18 -Me), 1.06 (3H, s, C18 -Me), 1.37 (s, tBu-Me's), 2.44-2.54 (1H, pr dd), 2.58-2.72 (1H, pr dd), 3.70 (1.6H, br, NH2), 5.13 (1H, s, NH), 5.97 (1H, dd), 6.30 (1H, dd); 13C NMR (CDCl3) δ 132.27, 132.44, 135.90, 171.51, 194.27. This compound has the following structure: ##STR3##

Provenance & Evidence