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In this report we highlight how short peptide sequences synthesized by standard or solid-phase, combinatorial techniques may interact with metal ions leading to efficient and stereoselective catalysts or sensing devices for the detection of proteins.

Oxidation of p-XC6H4SOMe (X = NC, F3C) by (alkylperoxo){tris[(2R)-2-hydroxy-2-phenylethyl]amine}titanium (2b ) has been shown to follow Michaelis-Menten kinetics demonstrating the occurrence of an intramolecular nucleophilic oxygen transfer to the TiIV-coordinated sulfoxide. The reaction of the titanium(IV) precursors 1 with sulfoxides has been studied by ESI-MS techniques together with ab initio calculations.

The control of the activity of HIV-1 protease by allosteric regulation of the efficiency of a putative inhibitor by Zn(II) ions was studied. The metal-binding template employed was tris(2-aminoethyl)amine to which to cross-link two peptides through a rigid aromatic spacer. The results showed that the activity of a dimerization inhibitor of HIV-1 protease derived from cross-linked interfacial peptides could be enhanced by controlling the conformation of their connecting unit through Zn(II) complexation. This provides a straightforward example of allosteric regulation of the activity of a synthetic inhibitor by a metal ion, and demonstrates that although Zn(II)-binding process occurs at a remote position, it amplifies the chemical information present in the system, i.e., its ability to recognize a monomer of HIV-1 protease.

Reaction of R-styreneoxide with glycine-tert-butylester yielded amino alcohols of the general formula (NRRR3)-R-1-R-2, where R-1 = CH2COO t Bu and R-2 = R-3 = 2-phenyl-2-hydroxyethyl (H(2)LA); R-2 = 2-phenyl-2-hydroxyethyl and R-3 = 1-phenyl-2-hydroxyethyl (H2LB); R-2 = H and R-3 = 2-phenyl-2-hydroxyethyl (HLC); and R-2 = H and R-3 = 1-phenyl-2-hydroxyethyl (HLD). The corresponding reaction with sarcosine-tert-butylester and subsequent hydrolysis provided the zwitterion (CH3){CH2CHPh(OH)}(CH2CO2-), HLE* (asterisk refers to unprotected carboxylate). Reaction of these ligands with VO(OiPr)(3) in CH2Cl2 gave the oxovanadium(V) complexes [VOL(OiPr)(2)] and [VOL2-(OiPr)] (for L-C and L-D) or, when reacted in the presence of MeOH, [VOL'(OMe)], where L' represents the methyl ester of L-A, L-B, and L-E. The crystal and molecular structures of R-HLC, S-HLD, R,S-HLE*center dot H2O, and Lambda[VO(R,S-L-B')OMe] have been determined. The complex [VOLB'(OMe)] contains vanadium in a distorted trigonal-bipyramidal array (tau = 0.72), the oxo group in the equatorial plane, and methoxide and N in the apical positions, and thus, it structurally models the active center of vanadate-dependent haloperoxidases. The structure and the bonding parameters, including a particularly long d(V-N) of 2.562 angstrom, are backed up by DFT calculations. The isolated oxovanadium(V) complexes and the in situ systems L VO(OiPr)(3) catalyze the oxidation, by cumylhydroperoxide HO2R', of prochiral sulfides (MeSPh, MeSp-Tol, PhSBn) to chiral sulfoxides plus some sulfone. The best results with respect to enantioselectivity (enantiomeric excess (ee) = 38%) were obtained with the system VO(OiPr)(3)/L-A, and the best selectivity with respect to sulfoxide (100%) was obtained with [VOLA(OiPr)]. The reaction with the hexacoordinated [VO(OMe)(HOMe)L-D*] was very slow. Oxidation of PhSBn is faster than that of MeSPh and MeSpTol. Turn-over numbers are up to 60 mol of sulfoxide mol(-1) of catalyst h(-1) (-20 degrees C). The unspectacular ee apparently is a consequence of flexibility of the active catalyst in solution, as shown by the V-51 NMR of the catalysts [VOL(OR)] and the oxo-peroxo intermediates [VOL(O2R')]. As shown by DFT calculations, the peroxo ligand coordinates in the tilted end-on fashion in the axial or equatorial position (energy difference = 17.6 kJ/mol).

To assess the prognostic value of corpus callosum lesions (CCL) and brain stem lesions (BSL) in diffuse axonal injury (DAI) patients.From December 1989 to December 2008, 102 consecutive patients with pure DAI were admitted to our neurosurgical intensive care unit. Age, gender, Acute Physiology and Chronic Health Evaluation score, Glasgow Coma Score (GCS), pupillary light reactivity on admission, brain magnetic resonance imaging (MRI) 24 hours to 72 hours after trauma and sepsis, shock, adult respiratory distress syndrome, renal failure, neurosurgery, high intracranial pressure during the 6 months posttrauma were studied with multiple logistic regression, and Cox's proportional hazards, respectively, considering the Glasgow Outcome Scale and the time to recovery of consciousness as outcome variables.Four variables predicted unfavorable Glasgow Outcome Scale (likelihood ratio p0.0001; Area Under the Receiver Operator Curve (AUROC)=0.92; Naglekerke's R=0.64; Goodness-of-Fit p=0.8679): age (5-year odds ratio [OR], 1.44; 95% CI, 1.14-1.82; p=0.002), bilateral absence of light reflexes (OR, 11.11; 95% CI, 2.19-57.67; p=0.004), multiplicity of CCL (OR, 29.23; 95% CI, 7.06-121.01; p0.001), and multiplicity of BSL (OR, 9.43; 95% CI, 2.44-36.42; p=0.001). Four variables affected time to recovery of consciousness: age (hazard ratio, 0.98; 95% CI, 0.97-0.99; p=0.009), bilateral absence of light reflexes (hazard ratio, 0.51; 95% CI, 0.27-0.97; p=0.041), multiplicity of CCL (hazard ratio, 0.40; 95% CI, 0.25-0.66; p0.001), and total GCS on admission (hazard ratio, 1.45; 95% CI, 1.23-1.71; p0.001).In DAI patients, bad outcome is predicted by age, bilateral absence of pupillary light reflexes, multiplicity of CCL, and BSL on MRI. Time to recovery of consciousness is predicted by age, bilateral absence of light reflexes, multiplicity of CCL on MRI, and GCS on admission.

A series of tris(2-aminoethyl)amine (TREN) derivatives functionalized on the arms with pyridine or methylimidazole ligands bind very strongly to a trisporphyrin derivative via apical coordination, with formation of molecular cages; the strength of the binding (Kb up to 108.8 mol−1 dm3) depends on the structure of the TREN derivative as well as on its coordination to Zn(II).