Tandem enzymatic resolution yielding L-alpha-aminoalkanedioic acid omega-esters

Synthesis of 2-aminosuberic acid derivatives as components of some histone deacetylase inhibiting cyclic tetrapeptides

A new synthesis of the important amino acid 2-aminosuberic acid from aspartic acid is reported. The methodology involves the alternate preparation of (S)-2-aminohept-6-enoate ester as a building block and its diversification through a cross-metathesis reaction to prepare the title compounds. The utility of the protocol is demonstrated through the preparation of three suberic acid derivatives of relevance to the design and the synthesis of peptides of biological relevance.

Homologs of 1,2,5-hexahydro-3-one-1H-1,4-diazepine (DAP) as novel dipeptidomimetics and molecular scaffolds: efficient preparation of synthons

Structurally constraint dipeptidomimetics represent an important class of conformationally rigid dipeptide surrogates and molecular scaffolds, which are frequently employed in peptide-based structure-activity relationships (SAR) and construction of combinatorial libraries. We report on the design of an improved and general synthetic procedure to prepare synthons related to the trisubstituted 1,2,5-hexahydro-3-one-1H-1,4-diazepines [DAP(Xxx)(alpha7)] (DAP: 1,2,5-hexahydro-3-one-1H-1,4-diazepine; DAP(Xxx)(alpha7): the homologous series of DAP in which alpha refers to the location of the chiral carbon in the i(th) amino acid, Xxx represents the three letter notation for the i-1 amino acids, and 7 denotes the number of atoms in the ring) and their higher homologs [DAP(Xxx)(alphaN)] [Xxx = Phe, Asp(beta-OcHex) (cHex: cyclohexyl), and Arg(N(G)-Tos] (Tos: p-toluenesulfonyl); N = 8-10]. These dipetidomimetic structures are generated by reductive alkylation-mediated Calpha(i)-to-N(i-1) bridging between a Calpha (i)-(CH(2))(i-1)(n)-COSEt (n = 1-4) and H(2)N-C(i-1)HR-CO(2)Fm (Fm: 9-fluorenylmethyl) followed by H(2)N(i)-to-C(i-1)-CO(2)H lactam formation. We also describe the preparation of blocked N-Ac-[DAP(Phe)(alphaN)]-CONMe(2) (N = 8-10), which serve as model systems for detailed conformational analysis reported in the accompanying article.