Development of NK3R Antagonists with a Degradable Scaffold in the Natural Environment: Synthesis and Application of Fused Piperazine Derivatives for Investigation of Degradable Core Motifs

For investigation of decomposable scaffolds for the fezolinetant triazopiperazine core in the natural environment, an efficient method for synthesis of [1,2,4]triazolo[4,3-a]piperazine derivatives was established based on gold(I)-catalyzed domino cyclization of an amidrazone substrate with a terminal alkyne. The amidoxime congeners were also converted into [1,2,4]oxadiazolo[4,5-a]piperazine derivatives in the presence of a gold catalyst.