Squalestatin 3,4-beta-lactone-4,5-dimethyl ester (8) was reductively ring-o
pened to yield squalestatin 3-hydroxymethyl-4,5-dimethyl ester (6) using mi
ld reducing conditions (sodium borohydride). Similarly squalestatin 3,4-oxe
tane-4,5-dimethyl ester (10) was found to ring-open to 3-iodomethyl squales
tatin (15) under the conditions used to cleave the methyl ester functions (
lithium iodide/2,4,6-trimethylpyridine). (C) 2000 Elsevier Science Ltd. All
rights reserved.