Solid-phase synthesis of polyamines using a Dde-linker: philanthotoxin-4.3.3 via an on-resin Mitsunobu reaction

A Dde linker/solid-phase procedure for the stepwise construction of polyami nes is illustrated with the synthesis of philanthotoxin-4.3.3. Resin-bound 4-aza-1,7-heptanediamine was N-4-protected and N-7-activated in a single op eration with 2-nitrobenzenesulphonyl chloride. Alkylation with N-Fmoc-4-ami nobutanol under Mitsunobu conditions completed the polyamine backbone. Depr otection of the sulphonamide groups was readily achieved with thiolates in DMF at room temperature. (C) 2000 Elsevier Science Ltd. All rights reserved .