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Risoluzione cinetica enzimatica di 2-fluoro-2-arilpropionati di metile” Seconda Scuola Estiva Nazionale “Chiralità molecolare: origine, riconoscimento ed applicazioni.
No full textMicellar Effects upon the Deprotonation of the 5-Nitroindole-2-Carboxylate Ion
No full textDeprotonation of the 5-nitroindole-2-carboxylate ion (1) at high pH is markedly increased by micelles of cetyltrimethyl ammonium bromide and hydroxide (CTABr and CTAOH). On the assumption that (1) and its dianion are fully micellar-bound the fraction, f, of deprotonated (1) can be related directly to the amount of micellar-bound OH–. and the basicity constant in the micelle is slightly smaller than in water
Synthesis of chiral (R)-4-hydroxy- and (R)-4-Halogeno[2.2]paracyclophanes and group polarizability - optically rotation relationship
No full textDEPROTONATION OF 5-NITROINDOLE AND ITS 2-CARBOXYLATE ION IN TWIN-TAILED SURFACTANTS
No full textDeprotonations of 5-nitroindole (1) and its 2-carboxylate ion (2) at high pH are increased by selfassemblies of didodecyldimethylammonium chloride and hydroxide (DDDACl and DDDAOH). The increased deprotonation can be accounted for quantitatively in terms of binding of OH– and the indicatiors to the colloidal self-assemblies. Basicity constants in the self-assemblies are similar to those in micelles of cetyltrimethylammonium chloride, bromide, and hydroxide (CTACl, CTABr, and CTAOH) and are slightly smaller than in water
AcGly-Phe-Asn(OH) and AcGly-Phe-Asn(NH2) tripeptides selectively affect the proliferation rate of MDA-MB 231 and HuDe cells
No full textThere is increasing interest in the bioactivity of peptides carrying out antiproliferative, antihypertensive, antimicrobial, antioxidant, anticholesterolemic, opioid, and antidiabetic activities. The bioavailability of peptides depends on how readily they are digested by endopeptidases and their ability to pass through cell membranes, features that are determined by the peptide's chemical and physical structure. On the basis of structures present in peptides that have biological activity, particularly antiproliferative activity, the tripeptides AcGly-Phe-Asn(OH) and AcGly-Phe-Asn(NH2) have been designed and synthesized, then tested for their antiproliferative activity on human breast adenocarcinoma cells (MDA-MB 231) and human dermal fibroblasts (HuDe). The results show that the peptides significantly affect the proliferation of MDA-MB 231 and HuDe cells, with differentiated response between tumor and normal cells, and thus indicate that C-terminal amidation plays a role. Interestingly, the activity of both peptides in dermal fibroblasts follows the characteristic biphasic pattern of hormesis, a dose-response relationship
THE EFFECTS OF SINGLE- AND TWIN-TAILED IONIC SURFACTANTS UPON AROMATIC NUCLEOPHILIC SUBSTITUTION
No full textReactions of OH– with 2,4-dinitro-1-chloro-benzene and -naphthalene have been examined in solutions of didodecyldimethylammonium chloride and hydroxide. Rate effects were analysed quantitatively in terms of distribution of reactants between water and the colloidal particles. Second-order rate constants at the surface of the particles are very similar to those in normal aqueous micelles of cetyltrimethylammonium hydroxide, chloride, and bromide and p-octyloxybenzyltrimethylammonium bromide and are slightly higher than in water. Similar observations were made on the reaction of OH– with 2,4-dinitro-1-fluorobenzene
NUCLEOPHILIC AROMATIC SUBSTITUTION IN SOLUTIONS OF CATIONIC BOLAFORM SURFACTANTS
No full textReactions of OH– with 2,4-dinitro-1-chloro-benzene and -naphthalene have been examined in solutions of the following bolaform surfactants: alkane-α,ω-bis(trimethylammonium bromide), alkane = docosane, hexadecane, and dodecane, [bolaform(22)Br, bolaform(16)Br, and bolaform(12)Br], bolaform(22)OH, and bolaform(16)OH. Rate effects of bolaform(22)Br and OH–were analysed quantitatively in terms of distribution of reactants between water and micelles and second-order rate constants at the micellar surfaces were very similar to those found with normal hexadecyltrimethylammonium micelles. Rate effects were much smaller with bolaform(16)Br and OH–but were typical of micellar rate enhancements, and bolaform (12)Br had even smaller effect
Nucleophilic aromatic substitution in twin — tailed hydroxide ion surfactants
No full textThe effects of didodecyldimethylammonium hydroxide and chloride upon reactions of OH with 2,4-dinitrochloro-benzene and napthalene are treated quantitatively in terms of the pseudophase model of micellar kinetics
“ Structure, Stability, and Activity of Myoglobin Adsorbed onto Phosphate-Grafted Zirconia Nanoparticles “Langmuir, 2007, 23, 13007.
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