Thiadiazoles

Synthesis of the 1,2,4-Thiadiazole Alkaloid Polyaurine B

“…Nucleophilic addition of hydroxide at C-5 leads to anion 17 , which gives rise to 18 upon acylation at N-2. Subsequent ring opening of 18 gives 19 , which upon loss of sulfur , gives 15 .…”