Conformationally restricted dipeptide

JA Robl, DS Karanewsky, MM Asaad. Synthesis of benzo-fused, 7,5- and 7,6-fused azapinones as conformationally restricted dipeptide mimetics. (N-methyhnorpholine and Pht-Asp(OBzl)-Cl) Tetrahedron Lett 36, 1593, 1995. 

The Rh-BIPHEPHOS-catalyzed cyclohydrocarbonylation has also been successfully applied to the rapid synthesis of a variety of l-azabicyclo[X.Y.O]alkane amino acids, which serve as conformationally restricted dipeptide surrogates for enzyme inhibitors and receptor antagonists, directly from dehydrodipeptide substrates (Scheme Reaction... 

Flynn, G.A., Giroux, E.L. and Dage, R.C. (1987) An acyl-iminium ion cycUzation route to a novel conformationally restricted dipeptide mimic applications to angiotensin-converting enzyme inhibition. J. Am. Chem. Soc. 109 7914-7915. 

Laufifer, D.J. and Mullican, M.D. (2002) A practical synthesis of (S) 3-tcrr-butoxy carbonylamino-2-oxo-2,3,4,5-tetrahydro-1,5-benzodia-zepine-1-acetic acid methyl ester as a conformationally restricted dipeptide-mimetic for Caspase-1 (ICE) inhibitors. Bioorg. Med. Chem. Lett. 12 1225-1227. 

G. A. Flynn, E. L. Giroux, and R. C. Dage,/. Am. Chem. Soc., 109, 7914 (1987). An Acyl-Iminium Ion Cyclization Route to a Novel Conformationally Restricted Dipeptide Mimic Applications to Angiotensin-Converting Enzyme Inhibition. 

Conformationally restricted cyclic dipeptides have several advantages over their linear counterparts ... 

Riva and coworkers obtained conformationally restricted cyclic peptidomimetics 13a and b by a tandem Ugi-4CR/RCM procedure as reported before (Scheme 13). The initial A-alkylated dipeptide moiety was formed in the Ugi reaction of A-Boc... 

Liskamp RMJ. Conformationally restricted amino acid and dipeptides, (non)peptidomimetics and secondary structure mimetics. Rec. Trav. Chim. Pays-Bas 1994 113 1-19. 

To solve the inactivation issues mentioned above, the concept of conformationally restricted (Z)-fluoro-olefm dipeptide isosteres that mimic the active trans conformation of the DPP IV inhibitors was applied by Welch and co-workers to the preparation of inhibitors having Ala-T fCF CHJ-Pro structure (76 and 78) and their inhibitory activities were evaluated (see Figure 10.6) [36, 37]. DPP IV inhibitory activities and the stability of the inhibitors 76 and 77, in comparison with those of the model dipeptide Ala-Pro derivative 78 are summarized in Table 10.2. These fluoro-olefin analogues, 76 and 77, showed better DPP IV inhibitory activity than that of 78. In particular, u-76 having the same relative stereochemistry as the natural dipeptide (L-Xaa-L-X aa) configurations exhibited potent... 

R. M. J. Liskamp, Reel. Trav. Chim. Pays-Bas, 113, 1 (1994). Conformationally Restricted Amino Acids and Dipeptides (Non)Peptidomimetics and Secondary Structure Mimetics. 

The pseudodipeptide 55 (see Scheme 10.16) was regarded as a conformationally restricted Xaa-Pro dipeptide and Scolastico et al. functionalized the azido-group by copper(l)-catalyzed dipolar cycloaddition with an alkynylated sugar, biotin or fluorescein to afford substituted triazolyl-Xaa-Pro-dipeptide mimics 56 in good to excellent yields. ... 

Muramic acid analogues, e.g. 67, have been synthesized fipom the azide 65 via lactam 66 (Scheme 20). Oxazolidine derivatives reported earlier (Vol.26, Ch.9, ref.37) have been converted into conformationally restricted muramoyl dipeptide analogues. ... 

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