Synthesis of Alternariolide Analogs for Photoaffinity-Labeling

Abs tract -Two photoaffinity-labeling analogs of alternariolide were synthesized.These peptides contain the 3-nitrophenyl-3-trifluoromethyldiazirine moiety for easy detection after irradiation experiment.Alternariolide (AM-toxin I, 1) is a host-specific phytotoxin produced by Alternaria mali. 1 The toxin causes necrotic brown spots on certain apple leaves that significantly damages the fruit.The hostspecificity should arise from the existence of a high-affinity protein to the toxin at the infection site of the plants for the fungal pathogen.2 To isolate the high-affinity protein, we have synthesized many labeling analogs of alternariolide (1). 3 HN CONH COO CONH CO CF 3 N N HN CONH COO CONH CO OMe Alternariolide (1) 2 HN CONH COO CONH CO CF