<jats:p> Treatment of Spicaria elegans with cytochrome P-450 inhibitor resulted in two new deoxy-cytochalasins, 7-deoxy-cytochalasin Z<jats:sub>7</jats:sub> (1) and 7-deoxy-cytochalasin Z<jats:sub>9</jats:sub> (2), which were recognized as plausible precursors of cytochalasins Z<jats:sub>7</jats:sub> and Z<jats:sub>9</jats:sub>, respectively. Their structures were elucidated by spectroscopic methods and the absolute configuration of 1 was determined by the conventional Mosher ester method. Their cytotoxicities against two cancer cell lines were evaluated.