Beilstein J. Org. Chem.2022,18, 174–181, doi:10.3762/bjoc.18.19
, such as histone deacetylases.
Keywords: chelatedenolate; Claisen rearrangement; HDAC inhibitor; peptide; late stage modification; Introduction
Among natural products, peptidic structures have entered the limelight due to their extraordinary biological activities [1]. Often found as secondary
Beilstein J. Org. Chem.2011,7, 1299–1303, doi:10.3762/bjoc.7.151
by chelatedenolate Claisen rearrangement [22][23] or transition metal-catalyzed allylic alkylation of chelated enolates [24] and subsequent oxidative cleavage of the γ–δ-unsaturated amino acids obtained.
Results and Discussion
An alternative approach is based on regioselective ring opening of
our chelatedenolate (Scheme 1) [29]. In this case an amino acid 4 with an allyl alcohol side chain was formed which could be oxidized to the α,β-unsaturated aldehyde 5. Although these types of aldehydes are critical candidates in Passerini and Ugi reactions [30], we were interested to see if we could
PDF
Graphical Abstract
Scheme 1:
Passerini reactions of α,β-unsaturated aldehyde 5.