were introduced, and systematic fluorine, bromine, and phenyl scans for phenylalanine in the P2 position were performed. Moreover, the N-terminal protection was varied. Kinetic investigations were carried out with cathepsin L, S, and K as well as papain. Changes in the backbone structure of the parent N-(tert-butoxycarbonyl)-phenylalanyl-glycine-nitrile (16), such as the introduction of an R-configured
Total syntheses of (+)-cinereain and (−)-janoxepin, two fungal cyclotripeptides featuring a complex heterocyclic core and interesting phytotoxic and antimalarial activities, have been achieved in a highly convergent manner. In the keystep, a one-pot cascade initiated by fragment coupling (cyclocondensation) was followed by a spontaneous retro-Claisen rearrangement to afford a 2,5-dihydrooxepin-fused