1,2,3-Triazole-Containing Azamacrocycles from Chiral Triazolopeptoids: Synthesis and Solid-State Studies.

Two new chiral 1,2,3-triazole-containing macrocyclic oligoamides (i. e.: triazolopeptoid 4 and 5) were obtained through solid-phase synthesis of linear precursors followed by high dilution macrocyclization reaction. Theoretical (DFT) and spectroscopic (NMR) studies revealed the intricate interplay between the Nα-chiral side chains and their conformational attitudes. BH3-mediated reduction of the tertiary amide groups of known 1-3 and newly synthesized 4 gave novel azamacrocycles 6-9. Detection of borane complexes of azamacrocycles 6 and 9 (i. e.: 10 and 11), corroborated by X-ray diffraction studies, demonstrated the peculiar properties of 1,2,3-triazole-containing macrorings.

Macrocyclic Triazolopeptoids: A Promising Class of Extended Cyclic Peptoids.

Head-to-tail cyclization of linear oligoamides containing 4-benzylaminomethyl-1H-1,2,3-triazol-1-yl acetic acid monomers afforded a novel class of "extended macrocyclic peptoids". The identification of the conformation in solution for a cyclodimer and the X-ray crystal structure of a cyclic tetraamide are reported.