The antibiotic streptomycin was the first drug used to treat TB and illustrated well the important role of nature in the fight against diseases. For example, several natural products were discovered between 1940-60´s against Mycobacterium tuberculosis being used nowadays in TB treatment as second-line drugs. Due to the importance of nature in the past and the present for TB treatment and drug discovery, a lot of attention has been given to new anti-TB drugs based on natural products nowadays, especially against MDR and XDR-TB. Considering that, the aim of the present chapter is to highlight promising natural product candidates in clinical trials against TB.
Keywords: Tuberculosis, Mycobacterium tuberculosis, natural products, semisynthesis, drug development, treatment, multi-drug-resistant tuberculosis (MDR TB), extensive-drug-resistant tuberculosis (XDR TB), target, mechanism of action, biological evaluation, clinical studies.