Synthesis and Utilization of Chiral α-Methylated α-Amino Acids with a Carboxyalkyl Side Chain in the Design of Novel Grb2-SH2 Peptide Inhibitors Free of Phosphotyrosine
alpha-aminoadipic acid (Adi) in position Y + 1. The enantiopure l(or D)-(alpha-Me)Aa bearing various chain length carboxylalkyl side chain was conveniently synthesized by an optimized oxazolidinone methodology. The incorporation of (S)-(alpha-Me)Aa into the non-pTyr-containing peptide framework with a 5-amino acid sequence binding motif of X (-2)-Leu-(3'-substituted-Tyr) (0)-X (+1)-Asn really improved the
Disclosed are N-acylsulfonamide compounds which inhibit the activity of anti-apoptotic protein family members, compositions containing the compounds and uses of the compounds for preparing medicaments for treating diseases during which occurs expression of one or more than one anti-apoptotic protein family member.
Disclosed are compounds which inhibit the activity of anti-apoptotic protein family members, compositions containing the compounds and uses of the compounds for preparing medicaments for treating diseases during which occurs expression one or more than one of an anti-apoptotic protein family member.
Convergent Synthesis of (−)-Mirabazole C Using a Chloroimidazolidium Coupling Reagent, CIP
作者:Kenichi Akaji、Naohiro Kuriyama、Yoshiaki Kiso
DOI:10.1021/jo952285h
日期:1996.1.1
Convergent synthesis of (-)-mirabazole C (1), a tetra thiazoline/thiazole alkaloid isolated from blue-green alga, has been described. The successive thiazoline rings of (-)-mirabazole C were formed by a single-step cyclization mediated by TiCl4 treatment of tripeptide amide 4. Convergent synthesis of the key intermediate 33 derived from three a-methylcysteine residues was first achieved using a newly developed coupling reagent, 2-chloro-1,3-dimethylimidazolidium hexafluorophosphate (CIP). The effectiveness of CIP for the coupling of alpha,alpha-dialkyl amino acids and the reaction pathway of the activation were clarified by the syntheses of model peptides containing an alpha,alpha-dimethylamino acid. A practical method of asymmetric synthesis of 2-methylcysteine by alkylation of 2,4-cis-oxazolidinone 23 has also been described.
CYCLIC COMPOUNDS AND COMPOSITIONS WHICH INHIBIT BONE RESORPTION