Cattienoids A-C, three novel steroids from the mushroom Tomophagus cattienensis

Three novel steroids (1-3), named cattienoids A-C together with schisanlactone A (4), were isolated from fruiting bodies of Tomophagus cattienensis (Ganodermataceae)-a new mushroom recently collected from Cattien National Park, in Viet Nam. They possess an unusual seven membered lactone ring, derived from lanostane-type triterpenoids. Their structures were determined by spectroscopic methods. In addition, compounds 2 and 4 showed cytotoxicity against KB (a human epidermal carcinoma) cells with their IC50 values of 91.2 and 63.3 mu M, respectively. These compounds have neither antimicrobial activity nor inhibition of the tyrosinase. (C) 2013 Elsevier B.V. All rights reserved.