An efficient synthesis of enantiomerically pure (1R,2S,5S)- and (1S,2R,5R)-rosaprostol methyl esters
We report a concise synthesis of the enantiomerically pure 1,2-trans-1,5-cis-methyl esters of rosaprostol, a prostaglandin derivative used for the treatment of gastric and duodenal ulcers, using as key step the chemo- and stereoselective Michael addition of a Grignard reagent to an unprotected hydroxycyclopentenone. Georg Thieme Verlag Stuttgart.
Murcia, M. Carmen,De La Herran, Gabriela,Plumet, Joaquín,Csaky, Aurelio G.
Lipase-Catalyzed Irreversible Transesterification Using Enol Esters: Resolution of Prostaglandin Synthons 4-Hydroxy-2-alkyl-2-cyclopentenones and Inversion of the 4S Enantiomer to the 4R Enantiomer
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Babiak, Kevin A.,Ng, John S.,Dygos, John H.,Weyker, Cara L.,Wang, Yi-Fong,Wong, Chi-Huey
Total synthesis of isoprostanes via the two-component coupling process
A short total synthesis of isoprostanes has been achieved using a two-component coupling process combined with a diastereoselective protonation under reagent control. The F1-isoprostanes were easily obtained by stereoselective reduction of the C-9 keto group.
Rodríguez, Ana R.,Spur, Bernd W.
p. 4575 - 4579
(2007/10/03)
An efficient asymmetric synthesis of prostaglandin E1
An asymmetric total synthesis of Prostaglandin E1 (5) has been achieved in a two-component coupling process. The chiral hydroxycyclopentenone 6 was readily available from furan with 96% ee. The key reaction step was a kinetic enzymatic resolution followed by an in situ inversion. A catalytic asymmetric reduction of the γ-iodo vinyl ketone 19 with the Corey CBS catalyst gave the ω-side chain 7 with >96% ee. Conjugate addition using the reaction with dilithiocyanocuprate followed by mild cleavage of the silyl protective groups and enzymatic hydrolysis of the methyl ester 22 gave (-)-PGE1 5 in high yield.