for the following products
1-Boc-4-(6-Nitropyridin-3-yl)piperazine | 4-(6-Nitro-3-pyridinyl)-1-piperazinecarboxylicacidtert-butylester | tert-Butyl 4-(6-nitropyridin-3-yl)piperazine-1-carboxylate and 4-(6-Nitropyridin-3-yl)piperazine-1-carboxylic acid tert-butyl ester
