3 NEW BIOACTIVE BIS-ADJACENT THF-RING ACETOGENINS FROM THE BARK OF ANNONA-SQUAMOSA

Continuing work on the bioactivity-directed fractionation of the bark of Annona squamosa has resulted in the discovery of three new Annonace ous acetogenins, (2,4-cis and tuans)-squamolinone (1), (2,4-cis and tr ans)-9-oxo-asimicinone (2), and bullacin B (3). Compounds 1-3 are all adjacent bis-THF ring acetogenins with 2 representing the first bis-ri ng acetogenin to contain a carbonyl along its aliphatic chain. Compoun d 3 was selectively cytotoxic in a panel of six human tumor cell lines with a potency of nearly a million times that of adriamycin against t he MCF-7 (human breast adenocarcinoma) cell line. (C) 1998 Elsevier Sc ience Ltd. All rights reserved.