Rational Design of Bacitracin A Derivatives by Incorporating Natural Product Derived Heterocycles
摘要:
Heterocycles display common structural motifs in nonribosomally produced peptides with an enormous impact on their bioactivity. In the case of the branched cyclic Bacitracin A, the thiazoline moiety is manufactured during NRPS peptide chain elongation. Here we describe a method to selectively alter the heterocyclic metal binding subunit of Bacitracin A by the synthesis of heterocyclic building blocks that were successfully coupled to the linear decapeptide and subsequently cyclized using the excised bacitracin PCP-TE bidomain. Utilization of this cyclase allowed the first generation of branched cyclic bacitracin derivatives containing thiazole and oxazoles. The generated bacitracin derivatives showed bactericidal activity, indicating the possibility of altering the biological important heterocyclic subunit and overcoming existing limitations for the application of bacitracin.
The rapid synthesis of oxazolines and their heterogeneous oxidation to oxazoles under flow conditions
作者:Steffen Glöckner、Duc N. Tran、Richard J. Ingham、Sabine Fenner、Zoe E. Wilson、Claudio Battilocchio、Steven V. Ley
DOI:10.1039/c4ob02105c
日期:——
A rapid flow synthesis of oxazolines and their oxidation to the corresponding oxazoles is reported. The oxazolines are prepared at room temperature in a stereospecific manner, with inversion of stereochemistry, from β-hydroxy amides using Deoxo-Fluor®. The corresponding oxazoles can then be obtained via a packed reactor containing commercial manganese dioxide.
The synthesis of a Microcystis aeruginosa predicted metabolite analog of aerucyclamide B was performed. This hexacyclopeptide was obtained from three heterocyclic building blocks by a convergent macrocycle-assembly methodology. The compound exhibited good in vitro antiplasmodial activity (IC50: 0.18 mu M, K1, cholorquine resistant strain). (c) 2012 Elsevier Ltd. All rights reserved.