9-Fluorenyl methoxy carbonyl(Fmoc)solid-phase synthesis of Fusukang was studied firstly
including stepwise solid-phase peptide synthesis(SPPS) and solid-phase convergent synthesis.The SPPS methodology utilized DMF as the coupling solvent
HBTU/HOBt/DIEA as the coupling reagent
Wang resin as solid supporter
TFA/p-methyl phenol/EDT/H2O(97∶0.25∶0.25∶2.5) as the cleavage condition
with 2-fold equivalent molar excess of protected amino acid.In the Fmoc solid-phase convergent synthesis of Fusukang
the effects of convergent protocol
coupling solvents
and coupling reagents on the yield of Fusukang were systemically studied
and the protocol of condensation process was optimized
i.e.using the sequential condensation of four protected peptide segments(1—10,11—20,21—25,26—36) with 1.5-fold equivalent molar excess of protected peptide segments in solvent; HATU/HOAt/DIEA (4-fold equivalent) as the coupling reagent; mixture DMF/DCM(1∶1
vol) as the coupling solvent; TFA/p-methyl phenol/EDT/H2O (97∶0.25∶0.25∶2.5) as the cleavage condition
washing resin 5 times with DCM before and after each reaction.The yield of crude Fusukang was 67.31%