Synthesis of the 1 , 2 , 4 - thiadiazole alkaloids polycarpathiamines A and B †
نویسنده
چکیده
In the presence of 1 mol% of a copper(II) catalyst and air, a readily available N-acetyl-N-thioacylguanidine undergoes a one-pot benzylic oxidation–oxidative heterocyclization sequence to give the 3-amino5-acyl-1,2,4-thiadiazole core of polycarpathiamines A (2) and B (3) and thus facilitating the first synthesis of both natural products. This methodology offers a straightforward alternative to the low yielding dipolar cycloaddition used to access 3-amino-5-acyl-1,2,4-thiadiazoles.
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