These structures illustrate the possibility to optimize the b-lactone scaffold for usage against rhomboids. We have shown that the b-lactones covalently and irreversibly react with the active site serine of GlpG. This makes them well suitable for use as ��warheads�� for ABPs. Compounds 31 and 43 contain an alkyne group in their structure, amenable to click chemistry-mediated derivatization. This feature allowed the direct on-gel visualization of the active rhomboid form. Hence, this study adds two new ABPs to the rhomboid chemical toolbox. Since blactones have already been successfully used for ABPP of serine hydrolases in lysates and live bacterial cells, we expect them to be useful tools for the in vivo functional study of bacterial rhomboids. Influenza A viruses infect a wide range of avian and mammalian hosts. The worldwide spread of avian flu as well as the subsequent outbreak of the 2009 H1N1 flu has raised public concerns of the global influenza pandemics due to the high morbidity and mortality. Vaccines and antiviral drugs are two available strategies in preventing and controlling influenza virus infections. It takes three to six months to create a vaccine for a newly emerged virus strain. Under this circumstance, antiviral drug for controlling virus infection is of great importance and necessity in the lag phase of the vaccine manufacturing. The envelope of influenza A viruses contains three important components: ion channel Fenoterol (hydrobromide) protein M2, surface glycoprotein hemagglutinin and neuraminidase. The M2 proton channel is responsible for proton CC-115 (hydrochloride) structure transfer which is a required process in viral replication. HA helps the virus recognize and invade the host cell, and NA which functions by cleaving the terminal sialic residues on the host cells can facilitate virus shedding. Currently, several types of inhibitors are available to treat this infectious disease, such as M2 inhibitors and NA inhibitors. However, numerous drug resistant cases to M2 inhibitors have been reported, so application of the M2 inhibitors was limited during some epidemics. To date, four anti-NA drugs have been approved, namely, Oseltamivir, Zanamivir, Peramivir, and Laninamivir. NA was divided into two groups based on phylogenetic distinction, group-1 NAs an
