Aromin and aromicin, two new bioactive annonaceous acetogenins, possessing an unusual bis-THF ring structure, from Xylopia aromatica (Annonaceae)

Our continuing activity-directed search for new bioactive compounds led to the isolation of two new, unusual, acetogenins, aromin (1) and aromicin (2), from the stem bark of Xylopia aromatica (Annonaceae). Both represent a new type of non-adjacent, bis-THF ring acetogenins (one THF ring being at C-4 to C-7 and the other at C-16 to C-19). Both show significant cytotoxicities among six human tumor cell lines; however, the activity is notably reduced compared to other non-adjacent bis-THF ring acetogenins. The structures of 1 and 2 were elucidated by spectroscopic methods and by derivatization.