2,4-Disubstituted oxazoles and oxazolines derive biosynthetically from processing of readily available serine residues by a nonribosomal peptide synthetase (NRPS) 1 and represent a common structural motif of many biologically active natural products. 2 More specifically, 4-formyl-2-(2- oxoalkyl)oxazoles 1 originate from the joint action of NRPS and polyketide synthase (PKS), 3 a pathway that results frequently in diverse and very potent secondary metabolites such ...
