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Ru2O-nH2O and [Ru3O(AcO)6(H2O)3j+AcO-were examined for catalytic activity in the hydrogenation of a series of unsaturated sulphides under heterogeneous and homogeneous conditions, respectively. By the appropriate combination of these two methodologies, a number of saturated sulphides could be synthesized in satisfactory to good yields, thus minimizing side reactions.

Several aromatic polyamides were prepared from 4,4′-[sulfonyl bis(p-benzoyl)(p-phenyleneoxy)]dibenzoic acid with various diamines by the phosphorylation route. The polymers were characterized by elemental analysis, thermogravimetric analysis, differential scanning calorimetry and infra-red analysis. The polyamides, obtained in quantitative yield, possessed inherent viscosities in the range 0.3–1 dl g−1and 10% weight loss in nitrogen and air were above 460 and 440°C, respectively. Most of the polymers were soluble in aprotic solvents. The effect of the structure on properties such as solubility and thermal behaviour were also studied.

Samples of poly(ethylene-iso/terephthalate)-perfluoro polyether multiblock copolymers with perfluoropolyether (PFPE) segments of different lengths have been characterized for surface composition by XPS and angular dependent XPS in order to determine the influence of the length of the PFPE blocks on the surface segregation of fluorine moieties. The results indicated that there was a high surface excess of PFPE when the PFPE blocks had molecular weight (MW) of 2200; for a bulk content of PFPE of about 8%, the amount of PFPE at the surface was 94 wt %. When the MW of PFPE blocks was 3400 or 1200, for the same bulk content of PFPE of about 8%, the surface showed a more limited excess of PFPE (about 46 and 30 wt % for MW 3400 and 1200 respectively). The segregation capability of PFPE blocks was also influenced by the length of polyester segments to which the PFPE blocks are bonded. So, when the fraction of PFPE bonded to very short segments of polyesters was extracted, the surface enrichment was reduced, and for a bulk composition of PFPE of about 6%, the surface amount of PFPE was of 15, 45, and 29% for PFPE with MW of 1200, 2200, and 3400, respectively. These data suggest that surface segregation depends on the MW of the initial PFPE and of the polyester segments bonded to PFPE after polymerization and that there is an optimum MW for PFPE surface segregation; the most favorable conditions are met for PFPE with MW 2200.

Paper was preserved by deposition of poly(cyclohexene oxide) polymerised in situ by a photoinitiated cationic process. The efficiency of the deposition, as function of parameters such as the used catalytic system and the reaction time, has been evaluated by detection of uncovered cellulose present at the sample surface determined by means of X‐ray photoelectron spectroscopy. The percentage of uncovered cellulose detected was ranging from 1 to 40%.

A new ultraviolet (UV)-curable acrylic monomer, 4,4'-hexafluoroisopropylidene-diphenoldihydroxyethylether diacrylate, was synthesized: it was cured as a film and its properties compared with those of its fully hydrogenated homologue. The introduction of two CF3groups into the monomer did not change its reactivity in the UV-curing reaction, but increased the glass transition temperature (Tg) of the cured polymeric film, decreased its refractive index (n), and lowered its surface tension. The fluorinated and the hydrogenated monomers were completely miscible and give homogeneous films: the Tg and n values were found linearly dependent on the fluorinated monomer content. The surface properties were deeply influenced by the presence of fluorine; a surface enrichment of the fluorinated monomer was evidenced by X-ray photoelectron spectroscopy analyses on the surfaces of the films obtained from mixtures of the two monomers. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 63: 979–983, 1997

To study the potential interaction between carbamazepine (CBZ) and selective serotonin reuptake inhibitors, fluoxetine (20 mg/day) and fluvoxamine (100 mg/day) were administered for 3 weeks to eight and seven epileptic patients, respectively, on chronic CBZ treatment. No significant changes in steady-state plasma concentrations of CBZ and its active metabolite, carbam-azepine-10,11-epoxide (CBZ-E) occurred, suggesting that CBZ metabolism is probably not affected by fluoxetine or fluvoxamine administration.

The effect of the selective serotonin reuptake inhibitor fluvoxamine (100 mg/day for 10 consecutive days) on the kinetics of a single oral dose of imipramine (50 mg) and desipramine (100 mg) was investigated in 12 healthy subjects. Compared with a control session, treatment with fluvoxamine caused a significant prolongation of imipramine half-life (from 22.8 ± 6.4 to 40.5 ± 5.0 h, means ± SD, p< 0.01) and a marked decrease in imipramine apparent oral clearance (from 1.02 ± 0.19 to 0.28 ± 0.06 L/h/kg, p< 0.0001). No significant changes in desipramine kinetics were observed during fluvoxamine treatment. These findings indicate that, at the dosage tested, fluvoxamine markedly inhibits the demethylation of imipramine without affecting significantly the CYP2D6-mediated hydroxylation of desipramine.

We have synthesized a (−)-Conduritol E derivative, enantiomerically pure, using as starting material D-mannitol. This latter, possessing already the same configuration of the expected product at the four chiral carbon atoms, was subjected to reaction to form a cyclic unsaturated polyhydroxylated compound, preserving the configuration at all chiral carbon atoms of the sugar.

A series of poly(ether sulfone)s and poly(ether ketone)s were synthesized from combinations of 1,5- and 2,6-bis(4-fluorosulfonyl)naphthalene, 2,6-bis(4-fluorobenzoyl)naphthalene, and 2,6-bis(4-fluorobenzoyl)quinoline with 3,3',5,5'-tetramethylbiphenyl-4,4'-diol and 2,2',3,3',5,5'-hexamethylbiphenyl-4,4'-diol. The polycondensations proceeded quantitatively in diphenylsulfone in the presence of anhydrous potassium carbonate to afford polymers with inherent viscosities between 0.40 and 1.28 dL/g measured in N-methyl-2-pyrrolidone or concentrated sulfuric acid. The tetramethyl- and hexamethyl-substituted aromatic polyethers exhibited good thermal stability, did not decompose below 330°C in both air and nitrogen atmospheres, and had higher glass transition temperatures than the corresponding unsubstituted polymers. The methylsubstituted poly(ether sulfone)s and poly(ether ketone)s showed good solubility in such common organic solvents as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, tetrahydrofuran, chloroform, and 1,4-dioxane.

A suitably positioned (1, 2-, 1, 4-, and 1, 5-) intramolecular sulfide interferes with the iodotrimethylsilane-promoted iodine for hydroxyl substitution, as well as the related alcohol deprotection procedure (regioselective cleavage of methyl ethers). The outcome may be a cyclic sulfonium salt or an iodide arising from cleavage of a sulfonium intermediate. Cyclization is especially favored with secondary and tertiary alcohols or ethers, and with an aliphatic more than an aromatic sulfide function. A transannular version of the reaction results in the facile ring contraction of a 7- to a 5-membered cyclic sulfide. The trimethyliodosilane-promoted iodine for hydroxyl substitution, as well as the related methyl ether cleavage reaction, fail for substrates where a sulfide function is suitably positioned relative to the oxygen function. The outcome may be either a cyclic sul fonium iodide or a rearranged sulfide arising from cleavage of a sulfonium intermediate as in the case of 4-methoxy thiepane

The effect of a new hydroxyphenyltriazine additive (Tinuvin 1577) on the surface photooxidation of polystyrene films at various concentrations of the additive was studied using ESCA spectroscopy. The accelerated weathering was run in a Xenotest apparatus to mimic outdoor conditions. The presence of Tinuvin 1577 effectively inhibited the surface photooxidation of polystyrene. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 1251–1256, 1998

New functionalised macromers containing perfluoropolyether (PFPE) structures and methacrylic end groups were synthesised and used as modifying additives for acrylic UV-curable systems. Their chemical structure is Rh-Rf-Rh, where Rh = —CH2O—CO—NH—CH2—CH2—O—CO—C=CH2CH3 and Rf = —CF2O—(CF2—CF2—O)p—(CF2—O)q—CF2—with p ≈ q. Notwithstanding their very low concentration, below 0.5 wt.-%, the fluorinated macromers cause a dramatic change of the surface properties of the films, without changing their curing conditions and their bulk properties. X-ray photoelectron spectroscopy (XPS) measurements showed that the macromers are able to concentrate selectively at the surfaces of the films, depending on their chemical structure and on the kind of substrate employed.

Several reports have been recently published concerning the identification of HBV variants due to rearrangements of the preS1/preS2 or core regions of the viral genome. To evaluate the frequency of the natural occurrence of such variants and whether the heterogeneity of these genomic regions correlates with the severity of the liver disease, we have examined the preS1/preS2 region and the entire core gene sequences of HBV DNA isolated from sera of 30 chronic HBV carriers, 7 with chronic persistent hepatitis, 10 with chronic active hepatitis, 7 with cirrhosis, and 6 with hepatocellular carcinoma. We found no significant rearrangement in any of the preS1 regions examined, while genomic modifications precluding the preS2 protein production were detected in 4 cases, 2 with cirrhosis and 2 with hepatocellular carcinoma. The analysis of the core gene showed the presence of various numbers of missense mutations in the core region of most cases, independent of the grade of liver disease. Moreover, in contrast with previous reports, neither mutation cluster region nor deletion was observed. On the contrary, HBV strains with the precore mutation at nucleotide position 1896, effecting the rise of HBeAg-defective viruses, were found in 26 of the 30 cases examined. In conclusion, our data show that the precore mutant is the only HBV genomic variant commonly selected during a chronic infection. Other HBV variants, due to genomic rearrangements outside the precore region, may exist and influence the outcome of the infection and the course of the liver disease, but the emergence of each of these variants seems to be an unusual and probably casual event.

An electron spectroscopy for Chemical Analysis (ESCA) characterization of films based on collagen-poly(vinylalcohol) blends, cross-linked by dehydrothermal treatment is reported. The semiquantitative analysis indicates a remarkable enrichment of collagen in the surface with respect to its initial percentage utilized to prepare the blends.

The acid-catalyzed transannular cyclization of 8–10-membered γ,δ-unsaturated cyclic sulfides yields cis fused bicyclic sulfonium salts independently of the geometry of the double bond. The rate varies linearly with the acidity function –(H0)I with a slope of 1. The rate variations span about six powers of ten range, the maximum rate difference being observed for the E/Z thiacyclooct-4-ene pair. The data are consistent with the classical interpretation of the intramolecular reactivity in terms of internal strain of the substrate and/or of the transition state.

Identification of asymptomatic hepatitis B virus (HBV) and hepatitis C virus (HCV) carriers is fundamental to reach the World Health Organization objective to eradicate viral hepatitis. The aim of this study was to evaluate the HBV and HCV prevalence among patients hospitalized for a non-liver-related disease but showing increased liver enzyme values.

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We describe four patients in whom the addition of fluvoxamine (100 mg/day) to the treatment with imipramine or desipramine (100–150 mg/day) resulted in a dramatic increase in the plasma concentrations of the tricyclic antidepressants associated with adverse effects. These observations indicate that fluvoxamine inhibits both the demethylation of imipramine and, possibly to a lesser extent, the hydroxylation of desipramine. The combination of fluvoxamine with tricyclic antidepressants should be avoided whenever possible.