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.