154 research outputs found
Orientation in Friedel-Crafts Acetylation of Nerolineand Its 6-Alkyl Homologues
The Friedel-Crafts acetylation of neroline in nitrobenzene medium is shown to result predominantly either in 1- or in 6-substitution,depending on the experimental conditions; as a byproduct, 1,6-diacetyl-2-methoxynaphthalene is obtained. Further,it is shown that 6-alkylated nerolines such as 6-propyl-2-methoxynaphthalene, are acetylated in position 1, even in nitrobenzene medium, and that 1,6-dialkylated nerolines such as 6-ethyl-2-
methoxy-1-methylnaphthalene, can also be acetylated, whilst 1,6-dialkyl-2-naphthols are unable to undergo Nencki acylation reactions. In the course of this work, certain errors in the literature have been corrected
Hydrox:ycetones possedant une activite protectricecontre les effets des radiations lethales
On a etudie la preparation au moyen de la methode de Nencki, de plusieurs acides superieurs aliphatiques ou alicycliques, avec le pyrogallol et l\u27a-naphtol; on obtien ainsi des cetones o-hydroxylees douees d\u27activite protectrice contre des doses lethales de rayons X. Il est en outre montre que la reaction de Nencki peut etre appliquee au 1,6-dihydroxynaphtalene, lequel a donne avec l\u27acide caprylique le 1,6- dihydroxy-2-octanoylnaphtalene
Emergence of Respiratory Streptococcus agalactiae Isolates in Cystic Fibrosis Patients
Streptococcus agalactiae is a well-known pathogen for neonates and immunocompromized adults. Beyond the neonatal period, S. agalactiae is rarely found in the respiratory tract. During 2002–2008 we noticed S. agalactiae in respiratory secretions of 30/185 (16%) of cystic fibrosis (CF) patients. The median age of these patients was 3–6 years older than the median age CF patients not harboring S. agalactiae. To analyze, if the S. agalactiae isolates from CF patients were clonal, further characterization of the strains was achieved by capsular serotyping, surface protein determination and multilocus sequence typing (MLST). We found a variety of sequence types (ST) among the isolates, which did not substantially differ from the MLST patterns of colonizing strains from Germany. However serotype III, which is often seen in colonizing strains and invasive infections was rare among CF patients. The emergence of S. agalactiae in the respiratory tract of CF patients may represent the adaptation to a novel host environment, supported by the altered surfactant composition in older CF patients
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