3α-N-[tert-butyl N-(3-[4-aminobutyl])-1,3-diaminopropyl dicarbamate]-7α-fluoro-22-hydroxy-23,24-bisnor-5α-cholane 在
pyridine-SO3 complex 作用下,
反应 4.0h,
以93%的产率得到(S)-2-((3R,5R,7R,8R,9S,10S,13R,14S,17R)-3-((3-((tert-butoxycarbonyl)(4-((tert-butoxycarbonyl)amino)butyl)amino)propyl)amino)-7-fluoro-10,13-dimethylhexadecahydro-1H-cyclopenta[a]phenanthren-17-yl)propyl hydrogen sulfate