Tuberculosis (TB) is one of the chronic infectious diseases caused by Mycobacterium tuberculosis that causes about 2-3 million deaths per year. Isoniazid and rifampicin are examples of first line drugs used for TB treatment; however, they are potentially hepatotoxic. More effective and safer drugs are urgently needed, especially from natural products. Basidiomycete mushrooms are known as important sources of pharmaceutically active metabolites including an anti-TB agent. In this work, the chemical constituents of the edible mushroom Astraeus odoratus were isolated and investigated for antibacterial activity against M. tuberculosis H(37)Ra. The cytotoxic activity against cancerous cell lines was also evaluated. Four new lanostane triterpenes, astraodoric acids A-D, and new 5-hydroxyhypaphorine have been isolated together with four known compounds. The structures were elucidated by NMR spectroscopic methods, HR-ESI-MS results, and X-ray crystallographic analysis. Astraodoric acids A and B exhibited moderate antibacterial (MICs of 50 and 25 μg/mL) and cytotoxic activities (IC(50) values of 34.69 and 18.57 μg/mL against KB and 19.99 and 48.35 μg/mL against NCI-H187), respectively. The results of this study show that A. odoratus could be a significant natural source for safer antitubercular and anticancer agents.

Astraodorol, a major lanostane-type triterpene isolated from the edible mushroom Astraeus odoratus, was subjected to chemical modifications. Ten derivatives have been synthesized and their biological activities were evaluated. Compounds 5, 6, 7a, 7c, 7e, 7f, and 7 g exhibited strong antimalarial activity with IC50 values of 4.85, 4.48, 4.16, 4.46, 3.45, 3.23, and 3.41 µg/mL, respectively. Compounds 7a, 7c, and 7e showed moderate cytotoxicity against NCI-H187 with IC50 values of 23.36, 34.28, and 9.84 µg/mL. Compound 7e demonstrated moderate cytotoxicity against KB, MCF-7, and Vero cell lines with IC50 values of 16.94, 49.60, and 26.48 µg/mL, respectively.