Resin‐bound phenylalanine boronates were prepared by solid‐phase Miyaura borylation of 4‐iodophenylalanine peptides. Subsequent arylation through a Suzuki–Miyaura cross‐coupling was carried out using a variety of aryl halides under conventional heating and under microwave irradiation. Microwaves greatly enhanced the arylation, shortening thereaction time and providing the biaryl peptides in higherpurities.

The first solid-phase strategy for the synthesis of cyclic depsipeptides containing a phenyl ester linkage in their structure is described. The key steps of the synthesis were the formation of the phenyl ester bond and the on-resin head-to-side-chain cyclization. The amino acid configuration significantly influenced the formation and the stability of the cyclic depsipeptides. The presence of a l-Tyr(1) and a d-Tyr(7) led to the most stable sequences.

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A rapid and efficient solid-phase strategy for the synthesis of dehydroxy fengycins derivatives is described. This synthetic approach involved the linkage of a Tyr to a Wang resin via a Mitsunobu reaction and the elongation of the peptide sequence followed by subsequent acylation of the N-terminus of the resulting linear peptidyl resin, esterification of the phenol group of a Tyr with an Ile, and final macrolactamization. The amino acid composition as well as the presence of the N-terminal acyl group significantly influenced the stability of the macrolactone. Cyclic lipodepsipeptides with a L-Tyr 3 /D-Tyr 9 configuration were more stable than those containing the Tyr residues with an opposite configuration. This work constitutes the first approach on the total solid-phase synthesis of dehydroxy fengycin derivatives.