Oxazole-peptide macrocycles

Fig. 6 Oxazole-peptide macrocycle libraries targeting G-quadruplex recognition...

DNA thiol-disulfide exchange 5 oxazole-peptide macrocycles [64]... 

Jantos K, Rodriguez R, Ladame S, Shirude PS, Balasubramanian S (2006) Oxazole-based peptide macrocycles a new class of G-quadruplex binding ligands. J Am Chem Soc 128 13662-13663... 

The Hantzsch reaction has also been utilized in the combinatorial synthesis of cyclic peptidomimetics 13 (14ACSCS001), peptide macrocycles 14 (14ACSCS71),oxazole-thiazole bis-heterocyclic compounds (14ACSCS39) (structures not shown). 

The total synthesis of the peptide derived macrocycle dendroamide A 163 has been accomplished in 19% overall yield from appropriately protected heterocyclic amino acids. The oxazole amino acid 162 resulted from cyclodehydration of P-ketodipeptide 161 with bis(triphenyl)oxodiphosphonium triflate, with notable chemo- and stereoselectivity <03JOC9506>. 

Thiopeptide antibiotics, thiazolyl peptides, naturally occurring sulfur-containing, highly modified, macrocyclic peptides. They share a number of structural motifs, including several heterocycles such as thiazoles, a dehydropiperidine, a pyridine, oxazoles, and indoles. Nearly aU of the thiopeptide antibiotics act as inhibitors of protein synthesis in bacteria. They are secondary metabolites produced by actino-mycetes, largely by the genus Streptomyces. A representative member of this family is thiostrepton [M. C. Bagleyetal., Chem. Rev. 2005, 105, 685]. 

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