Homologation of L-phenylalanine to ketomethylene and hydroxyethylene dipeptide isosteres via 2-thiazolyl amino ketone intermediate
摘要:
A highly efficient route is presented for the synthesis of N-protected isosteric dipeptides Phepsi[COCH2]Gly and Phepsi[CH(OH)CH2]Phe from L-phenylalanine through 2-thiazolyl alpha-amino ketone and delta-amino-gamma-hydroxy-(E)-alpha,beta-enoate derivatives as key intermediates.
Synthesis of novel glycopeptidomimetics via Nβ-protected-amino alkyl isonitrile based Ugi 4C reaction
作者:Basavalingappa Vasantha、Girish Prabhu、Hosmani Basavaprabhu、Vommina V. Sureshbabu
DOI:10.1016/j.tetlet.2013.06.013
日期:2013.8
The Ugi-4C reaction employing Nβ-protected-amino alkyl isonitrile, amino acid ester, aldehyde, and glycosyl acid has resulted in novel glycosylated peptidomimetics. The extension of MCR products for the synthesis of N,N′-orthogonally protected glycosylated peptidomimetics has also been demonstrated.
A short and diastereoselective synthesis of newly reported aza-diketopiperazine (aza-DKP) scaffolds starting from amino-acids was achieved using domino Rh(i)-catalyzed cyclohydrocarbonylation/addition.
for asymmetric [3+2] cycloaddition reactions. A silver complex prepared from silver bis(trimethylsilyl)amide (AgHMDS) and (R)‐DTBM‐SEGPHOS worked well in asymmetric [3+2] cycloaddition reactions of α‐aminoester Schiff bases with several olefins to afford the corresponding pyrrolidine derivatives in high yields with remarkable exo‐ and enantioselectivities. Furthermore, α‐aminophosphonate Schiff bases
Silver lining: Highly exo‐selective asymmetric [3+2] cycloaddition of α‐amino ester Schiff bases with activated olefins proceeds in the presence of AgHMDS/1. The α‐amino ester Schiff bases including those derived from aliphatic imines successfully reacted to afford the corresponding pyrrolidine derivatives in high yield with high exo‐ and enantioselectivities. EWG=electron‐withdrawing group, HMDS=