No abstract

Herein we report the screening of a small library of aurones and their isosteric counterparts, azaaurones and N‐acetylazaaurones, against Mycobacterium tuberculosis. Aurones were found to be inactive at 20 μm, whereas azaaurones and N‐acetylazaaurones emerged as the most potent compounds, with nine derivatives displaying MIC99 values ranging from 0.4 to 2.0 μm. In addition, several N‐acetylazaaurones were found to be active against multidrug‐resistant (MDR) and extensively drug‐resistant (XDR) clinical M. tuberculosis isolates. The antimycobacterial mechanism of action of these compounds remains to be determined; however, a preliminary mechanistic study confirmed that they do not inhibit the mycobacterial cytochrome bc1 complex. Additionally, microsomal metabolic stability and metabolite identification studies revealed that N‐acetylazaaurones are deacetylated to their azaaurone counterparts. Overall, these results demonstrate that azaaurones and their N‐acetyl counterparts represent a new entry in the toolbox of chemotypes capable of inhibiting M. tuberculosis growth.

Despite being discovered and isolated more than one hundred years ago, tuberculosis (TB) remains a global public health concern arch. Our inability to eradicate this bacillus is strongly related with the growing resistance, low compliance to current drugs, and the capacity of the bacteria to coexist in a state of asymptomatic latency. This last state can be sustained for years or even decades, waiting for a breach in the immune system to become active again. Furthermore, most current therapies are not efficacious against this state, failing to completely clear the infection. Over the years, a series of experimental methods have been developed to mimic the latent state, currently used in drug discovery, both in vitro and in vivo. Most of these methods focus in one specific latency inducing factor, with only a few taking into consideration the complexity of the granuloma and the genomic and proteomic consequences of each physiological factor. A series of targets specifically involved in latency have been studied over the years with promising scaffolds being discovered and explored. Taking in account that solving the latency problem is one of the keys to eradicate the disease, herein we compile current therapies and diagnosis techniques, methods to mimic latency and new targets and compounds in the pipeline of drug discovery.