DIPEA catalyzed step-by-step synthesis and photophysical properties of thieno[2,3-b]pyridine derivatives

A series of novel 5,6-disubstituted ethyl 3-amino-4-cyanothieno[2,3-b]pyridine-2-carboxylates was synthesized. The reaction conditions were thoroughly studied and intermediate ethyl 2-((3,4-dicyanopyridin-2-yl)thio)acetates were successfully isolated in good yields. For all synthesized compounds, spectral-fluorescent properties were carefully investigated and correlation thereof with chemical structure was found.     

On the paradox of TiCl4 reducing power: pinacol coupling and two-carbon homologation of carbonyl compounds

TiCl₄/DIPEA/CH₂Cl₂ reducing system promotes pinacol coupling and/or reduction to alcohol of aromatic aldehydes and carbonyl compounds activated towards reduction by an electron withdrawing group. In addition, bis homologation of these substrates is observed. An inner-sphere electron transfer from TiCl₄ to DIPEA accounts for the products distribution.     

Fluorinated peptidomimetics: synthesis, conformational and biological features

Peptides modified with fluoroalkyl functions in key backbone positions have been scarcely studied so far. Thus, little is known about their synthesis, their structural and physico-chemical properties, and their biological features. Our interest in this field of research led to the development of stereocontrolled synthetic protocols, both in solution and in solid phase, for many different fluoroalkyl peptidomimetics, some of which are overviewed in this paper: (a) ψ[CH(CF₃)NH]-peptide mimics holding a great potential as hybrids between natural peptides and hydrolytic transition state analogs; (b) trifluoromethyl (Tfm) malic peptidomimetics as micromolar inhibitors of some matrix metalloproteinases; (c) bis-Tfm analogs of Pepstatin A, that are nanomolar and selective inhibitors of the protozoal aspartyl protease Plasmepsin II.