1,720,973 research outputs found
Synthesis and elaboration of peptidomimetic units
No full textRetro-peptides are peptidomimetics that present the direction of the amino acidic sequence reversed. A classical retro modification can be obtained by the introduction of the malonyl unit followed by a gem-diaminic unit, that can result in an increase of proteolysis resistance of the related parent peptide, retarding degradation and consequently enhancing therapeutic efficacy.This thesis aims at developing synthetic stategies to synthesize new interesting building blocks for the construction of peptidomimetics containing a retro modification.In this field Meldrum’s acid is recently reported as a useful scaffold to obtain non-symmetric disubstituted malonamides rAA-mGly-AA′ as building blocks for the synthesis of retro-peptides. The attention has been turned towards the synthetic elaboration of different rAA-mGly-AA′ with the aim of introducing, into the malonamide backbone, the olefinic moiety by a Knoevenagel condensation, obtaining correspondig malonyl dehydro peptides MDHPs.The investigation of a further elaboration was carried out to obtain the corresponding epoxy and aziridino peptides,interesting building blocks containing electrophilic sites known to react with nucleophilic amino acids within the active site of proteases. Starting from L-amino acids, a new methodology is presented for the synthesis of gem-diaminic units g-AA that replace the sense of direction of amino acids in retro-peptide chain.In the field of amino acid and peptide modifications by palladium catalysed reactions, in the University of Bath a methodology has been developed to synthesise biphenyl lysine derivatives by a two step procedure, where the key step involves a Suzuki cross-coupling reaction
“NMR Chemosensing” Using Monolayer-Protected Nanoparticles as Receptors
Full text linkA new sensing protocol based on NMR magnetization transfer sequences and the molecular recognition abilities of nanoparticles allows the detection and identification of organic molecules in complex mixtures
A novel deacylation during the amination of trifluoromethyl beta-dicarbonyl compounds
No full textStarting from trifluoromethyl beta-dicarbonyl compounds, a rare loss of CF3CO was observed in the amination reactions performed under heterogeneous conditions using NsONHCO(2)Et as the aminating agent and CaO or NaH as the base, while corresponding nonfluorinated beta-dicarbonyl compounds under analogous conditions give non deacylated aminated compounds. This reaction can facilitate a direct synthesis of N-substituted alpha-amino esters or alpha-amino ketones. (C) 2007 Elsevier Ltd. All rights reserved
Metodo di Rilevamento di Molecole Organiche Mediante Spettroscopia di Risonanza Magnetica Nucleare e Nanoparticelle di Oro
No full textL’invenzione è relativa ad un metodo di rilevamento di molecole organiche mediante spettroscopia NMR a trasferimento di magnetizzazione da nanoparticelle d’oro funzionalizzate con un monostrato di molecole organiche e all’uso delle nanoparticelle d’oro funzionalizzate per il metodo stesso
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