Departament d’Enginyeria Quı́mica, E. T. S. d’Enginyeria Industrial de Barcelona, Universitat Politècnica de Catalunya, Diagonal 647, Barcelona E-08028, Spain, Departamento de Quı́mica Orgánica, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza CSIC, 50009 Zaragoza, Spain, Departament de Quı́mica, Escola Politècnica Superior Universitat de Lleida, c/Jaume II No 69, Lleida E-250...

The collagen telopeptides play an important role for lysyl oxidase-mediated crosslinking, a process which is deregulated during tumour progression. The DEKS motif which is located within the N-terminal telopeptide of the α1 chain of type I collagen has been suggested to adopt a βI-turn conformation upon docking to its triple-helical receptor domain, which seems to be critical for lysyl oxidase-...

We report the solid-phase synthesis and some pharmacological properties of twenty oxytocin (OT) analogues. Basic modifications at position 7 (introduction of alpha-aminoisobutyric acid [Aib], L- or D-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid [L/D-Tic], L-alpha-t-butylglycine [Gly(Bu(t))] and pipecolic acid [Pip]) were combined with D-Tyr(Et)(2), L/D-(pEt)Phe(2), D-Tic(2), and Mpa(1) modi...

A new method for the regioselective synthesis of 2-alkoxycarbonyl- and 2-(aminocarbonyl)phenylglycinate methyl esters has been developed. The reaction of the orthopalladated complex [Pd(μ-Cl)(C(6)H(4)(CH(CO(2)Me)NMe(2))-2)](2) (1) with nucleophiles HNu under a CO atmosphere results in the selective incorporation of the C(O)Nu moiety to the phenyl ring and formation of the carbonyl species ortho...

2',3'-Lyxoanhydrothymidine (LAT), a conformationally restricted inhibitor of retroviral reverse transcriptases, has been studied by X-ray analysis. The unit cell contains two crystallographically independent molecules A and B. Their sugar moieties have an identical structure: an 04'-endo pucker of the furanose cycle and a trans conformation about the exocyclic C4'-C5' bond. The conformations of...

Elongation factor G (EF-G) from Escherichia coli is a large, five-domain GTPase that promotes tRNA translocation on the ribosome. Full activity requires GTP hydrolysis, suggesting that a conformational change of the factor is important for function. To restrict the intramolecular mobility, two cysteine residues were engineered into domains 1 and 5 of EF-G that spontaneously formed a disulfide c...

Nanostructures including hydrogels based on peptides containing non protein amino acids are being considered as platform for drug delivery because of their inherent biocompatibility and additional proteolytic stability. Here we describe instantaneous self-assembly of a conformationally restricted dipeptide, LeuΔPhe, containing an α,β-dehydrophenylalanine residue into a highly stable and mechani...

A chiral synthesis of a series of hexahydroisobenzofuran (HIBF) nucleosides has been accomplished via glycosylation of a stereo-defined (syn-isomer) sugar motif 16 with the appropriate silylated bases. All nucleoside analogs were obtained in 52-71% yield as a mixture of alpha- and beta-anomeric products increasing the breadth of the novel nucleosides available for screening. The structure of th...

1 The isolated spinal cord of the frog (Rana pipiens) was used to examine the structural requirement for the activity of neutral amino acids. The potencies of the aliphatic amino acids, gamma-aminobutyric acid (GABA), beta-alanine and glycine were compared with the potencies of conformationally restricted cyclopentane and cyclohexane amino acid analogues. Both motoneurone hyperpolarizing and pr...

BACKGROUND CB1 cannabinoid receptors are G-protein coupled receptors for endocannabinoids including anandamide and 2-arachidonoylglycerol. Because these arachidonic acid metabolites possess a 20-carbon polyene chain as the alkyl terminal moiety, they are highly flexible with the potential to adopt multiple biologically relevant conformations, particularly those in a bent form. To better underst...