反应详情

To a solution of 500 mg of 5-amino-1-(tert-butoxycarbonyl)-4-methyl-benzimidazole in 20 mL of tetrahydrofuran are added 753 mg of ethyl N,N-bis(benzyloxycarbonyl)pseudothiourea and 645 mg of mercuric acetate and the mixture is stirred at room temperature for 1 hour. The resulting suspension is diluted with ethyl acetate and washed with water followed by brine. The aqueous layers are extracted with ethyl acetate; the combined organic layers are dried over magnesium sulfate, filtered and rotary evaporated. The residue is purified by flash column chromatography on silica gel, eluting with 50% ethyl acetate/hexanes followed by recrystallization from hexanes/methylene chloride to provide 927 mg of 1-(tert-butyloxycarbonyl)-5-[N2, N3-bis(benzyloxycarbonyl)-guanidino]-4-methylbenzimidazole as a white solid.

1. washwashed with water
2. extractionThe aqueous layers are extracted with ethyl acetate
3. dry with materialthe combined organic layers are dried over magnesium sulfate
4. filtrationfiltered
5. customThe residue is purified by flash column chromatography on silica gel
6. washeluting with 50% ethyl acetate/hexanes
7. customfollowed by recrystallization from hexanes/methylene chloride