Synthesis of a Conformationally Flexible β‐Hairpin Mimetic

Abstract

Dedicated to Professor Dieter Seebach on the occasion of his 65th birthday Rational conformation design led us to a synthesis of the w-amido-undecenamide 4, which was shown by theoretical means (simulated annealing techniques) and by NMR and IR spectroscopy to have a high tendency to populate a conformation corresponding to a natural b-II'-type hairpin, despite possessing a conformationally fully flexible open-chain backbone.

An Evaluation of Peptide‐Bond Isosteres

“…Analogously, Hoffman and coworkers have employed gauche pentane interference in the design of β-turn mimics. [49] Some of these β-turn mimics have been shown to be strong nucleators of β-sheet formation in a Pin 1 WW domain. [50] …”

Total Synthesis of (−)‐atrop‐Abyssomicin C

“…Aldehyde 23 was obtained in optically pure form, from cis-2,4-dimethylglutaranhydride, [21] according to the literature procedure. [22] Treatment of 23 with lithiated 19, followed by quenching the reaction with methoxymethyl bromide, gave protected allylic alcohol 24 as a mixture of diastereoisomers. The vinyl group was transformed into an aldehyde to give 25; correction of the stereochemistry of the aldehyde-bearing stereocenter was accomplished through base-catalyzed epimerization.…”

A Practical, Enantioselective Synthesis of the Fragrances Canthoxal and Silvial®, and Evaluation of Their Olfactory Activity

“…methyl sulfide complex (BMS), a reducing reagent which assures complete configuration retention at the α-carbon 18 and short reaction times. In fact, at room temperature, 1gram-scale reductions of (+)-4a and (-)-4a were complete in 1 hour, giving (-)-5a and (+)-5a, respectively.…”