Hydrochloric Acid → Cholesterol TREN bis-guanidinium methylphosponamidate

Participants

Reaction Steps

Compound (18) (0.148 g, 0.25 mmol) was dissolved in anhydrous DMF (1.0 ml) and anhydrous dichoromethane (5.0 ml). 1-H-pyrazole-1carboxarnidine.HCl (73 mg, 0.50 mmol) was added to the reaction mixture followed by diisopropylethylamine (87 ml, 0.50 mmol). Dichloromethane was stripped off of the reaction mixture on a rotovap then rotation continued overnight without vacuum at room temperature. After removing DMF in vacuo the reaction residue was dissolved in dichloromethane and applied to a flash silica gel column. A gradient of 5 to 20% MeOH/dichloromethane with 0.5 to 2% NH4OH followed by treatment with Dowex OH− (300 mg) in MeOH gave pure (19): 0.11 g, 65%, 31P NMR (d, 33.83 ppm), mass spec. calcd=676.97. Found=677.54.

Provenance & Evidence