English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Diastereoselective methylation of the enolate generated from various protected 6-oxopipecolic acid esters (3aa-3cd) was studied. The protecting groups on the carboxylic acid and amino groups significantly influenced the trans/cis selectivity in the methylation reaction. The optimal substrate (3ca), bearing benzhydryl ester and carbobenzyloxy moieties gave a trans/cis isomer ratio of ca. 4 : 1. Investigation of the reaction conditions revealed that the reaction solvent, alkylating reagent, and base employed to generate the enolate, were decisive factors for diastereoselectivity. Further optimization of reaction conditions, including the amounts of the reagents and their addition sequence enabled maximization of reaction conversion and minimization of by-products to produce the trans rich 5-methyl-6-oxopipecolic acid ester (4ca) on a large scale.

Synthesis of a New Dual Metalloprotease Inhibitor. I. Diastereoselective Alkylation of Protected 6-Oxopipecolic Acid Esters.