- Synthesis of 6-acetamido-5-amino- and -5-guanidino-3, 4-dehydro-N-(2-ethylbutyryl)- 3-piperidinecarboxylic acids related to zanamivir and oseltamivir, inhibitors of influenza virus neuraminidases. Shitara, E., Nishimura, Y., Nerome, K., Hiramoto, Y., Takeuchi, T. Org. Lett. (2000)