| Abstract
| - The total synthesis of two mono-THF acetogenins, tonkinecin (1) and annonacin (2), is reported infull detail. Terminal acetylene 3 prepared from d-glucono-δ-lactone and asymmetric dihydroxylationwas employed as a common intermediate for both targets 1 and 2. Pd(0)-catalyzed coupling reactionof 3 with vinyl iodides 4 and 5, the chiral centers of which were taken from d-xylose and S-(−)-ethyl lactate, afforded enyne 26 and 27, respectively. Selective hydrogenation of 26 or 27 withdiimide followed by removal of MOM ethers completed the synthesis of 1. A coupling reactionbetween the lithium derivative of 3 and epoxide 6 in the presence of boron trifluoride etherategave 42. Both chiral centers in epoxide 6 were taken from l-ascorbic acid. Subsequent catalytichydrogenation and MOM protection led to 43b. Introduction of the butenolide moiety by aldolcondensation of protected S-lactal followed by cleavage of all MOM ethers completed the synthesisof 2.
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