An Efficient Asymmetric Synthesis of Prostaglandin E1

Prostaglandin E1 Is an Efficient Molecular Tool for Forest Leech Blood Sucking

“…The 13C NMR and DEPT (Distortionless Enhancement by Polarization Transfer) spectra displayed signals for one ketone, one carboxyl carbon, double bonds, four methines (two oxygenated), 11 methylenes, and one methyl, thus assigning one ring and a chain moiety to the structure. The 13C and 1H NMR ( Figure 3B) spectral data were similar to those of prostaglandin, especially PGE1 (13)(14)(15)(16)(17)(18). Based on detailed comparison of the MS and NMR spectral data and optical rotation with that of PGE1, we tentatively identified our compound as PGE1.…”

Beyond Neuroprostanes: Total Synthesis and Epilipidomic Studies of a Novel Cyclopentenone Metabolite of Docosahexaenoic Acid

“…Reduction of the α,β‐unsaturated ketone using the Corey–Bakshi–Shibata oxazaborolidine catalyst [ 32 ] proceeded with only modest diastereoselectivity and after introduction of the TBS protecting group, silyl ether 1a was obtained in 82% yield over two steps as a mixture of four diastereomers; the major diastereomer at the newly formed C‐4 stereocenter was assigned as (4 S )‐ 22 based on related literature reports. [ 33 , 34 , 35 ] The primary TES ether group was subsequently transformed to the corresponding aldehyde by Swern oxidation, [ 35 ] which was subjected to a Wittig reaction using a combination of phosphonium salt 2 and NaHMDS in THF at low temperature. [ 25 ] The reaction furnished orthogonally protected skipped triene 22 with all 22 carbons of the target compound in place in 50% yield over two steps.…”

Synthesis of the Right-Hand Substructure of Solanoeclepin A

“…The primary silyl ether was then oxidised selectively under Swern conditions to afford the aldehyde 14. [10] This two-step sequence allowed the facile differentiation of the primary and secondary hydroxyl groups. Scheme A Wittig olefination of aldehyde 14 resulted in the formation of the terminal alkene 15, which was envisaged to be a good starting material for the introduction of the cyclopropane carboxylic acid moiety.…”