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Abstract
Rotaxanes are compounds in which ring fragments are locked to thread fragments via non-covalent
interactions. In nature, bacteria are known to synthesize lasso peptides, which are [1]rotaxanes.
These peptides are known to exhibit anti-microbial behaviour and some have other biological
activities such as HIV inhibition.
In order to synthesise rotaxanes a new approach has been envisioned. A ring fragment and a linear
fragment will be ligated to a molecular scaffold. Via an addition or cyclisation the ring fragment is
ring closed around the linear fragment. Subsequently, the scaffold is removed and the free rotaxane
is obtained.
This present research is intended as a preliminary test to examine whether it is possible for a ring
fragment to ligate and cyclise when it is bound to the scaffold.
A ring fragment and scaffold were synthesised and coupled via an oxime ligation. The ring fragment
was cyclised using Grubbs second generation catalyst. Although the compound wasn’t obtained in
pure form, LC-MS measurements give reason to believe that ring closure was successful. Removal of
the scaffold was not investigated due to shortage of time, but the way to further research has been
paved.