Synthesis of the key component for preparation of 6-ketoprostaglandins by a two-component coupling process: synthesis of 6-keto-prostaglandin E<sub>1</sub>, ornoprostil and Δ<sup>2</sup>-trans-6-ketoprostaglandin E<sub>1</sub>
作者:Yasufumi Kawanaka、Naoya Ono、Yukio Yoshida、Sentaro Okamoto、Fumie Sato
DOI:10.1039/p19960000715
日期:——
Starting with commercially available (3S,4R)-3-(methoxymethyloxy)-2-methylidene-4- siloxycyclopentanone-2, useful 6-keto-prostaglandin intermediates 1 have been prepared in good yields by a sequence of reactions which includes treatment with NaBr in the presence of BF3 . OEt(2), Pd-catalysed coupling of the resulting 2-bromomethyl-4-siloxycyclopent-2-enone 3 with the alkenylborane 4 or 9 and conversion of the alkenyl moiety into an epoxy and then into a keto group. The synthesis of 6-keto-PGE(1), ornoprostil and Delta(2)-trans-6-keto-PGE(1) by using 1 is also described.