The nickel hydroxide electrode has proved to be a versatile, inexpensive and facile applicable reagent, that allows an easy scale-up of the oxidation. It furthermore exhibits a remarkable selectivity ...to oxidize the sterically less shielded functional group. It is to be expected, that further applications of the electrode will be developed, which are partly guided by experiences with nickel peroxide oxidations. Furthermore additional chemoselectivities may be found by the use of other transition metal oxide electrodes, e.g. copper-, silver- and cobalt oxide electrodes.
2-(5-Chlorocarbonyl-2-oxazolyl)-5, 6-methylenedioxybenzofuran was found to be a highly sensitive fluorescence derivatization reagent for primary, secondary and tertiary alcohols in high performance ...liquid chromatography. Its reactivity was investigated for 1-hexanol, benzyl alcohol, cyclohexanol and 2-methyl-2-butanol. The reagent reacts with the alcohols in benzene in the presence of pyridine to produce the corresponding fluorescent esters, which could be separated on a reversed phase column, Cosmosil 5C18, with aqueous 70% (v/v) acetonitrile; the detection limits (S/N=3) were 3-4fmol for 1-hexanol and benzyl alcohol, 12fmol for cyclohexanol and 900fmol for 2-methyl-2-butanol for an injection volume of 20μl. Hydroxycarboxylic acids did not give fluorescent derivatives under these conditions.
Conversion of primary alcohols to the corresponding thiocyanates was effected by constant-current electrolysis of thiocyanate ion in dichloromethane containing an alcohol, triphenylphosphite, and 2, ...6-lutidinium perchlorate or tetrafluoroborate. The electrolysis was performed at ambient temperature in a one-compartment cell using a graphite plate and a platinum plate as the anode and the cathode, respectively. 2, 6-Lutidinium cation effectively extracted thiocyanate ion into the organic phase from sodium thiocyanate suspended in the reaction mixture.
Quorum Sensing in Fungi Fink, Gerald R; Tseng, Claire C
Chemical Communication among Bacteria,
2008
Book Chapter
The most well studied of the more recently identified quorum‐sensing molecules in fungi are small primary alcohols, thus chemically different from the acyl‐homoserine lactones and modified peptides ...preferred by bacteria. These primary alcohols include farnesol and tyrosol in Candida albicans, and phenylethanol and tryptophol in Saccharomyces cerevisiae. This chapter talks about molecules after a review of the mating pheromones and a more detailed discussion of the primary alcohol quorum‐sensing molecules. In S. cerevisiae, members of the same mitogen‐activated protein kinase (MAPK) signaling cascade are involved in both pheromone response and agar invasion in haploid cells, and in Ustilago maydis, the loci expressed in response to mating pheromone contain genes involved in filamentous growth and pathogenicity. This coordination between mating and morphogenesis in fungi is analogous to the connection between competence and virulence in Streptococcus pneumoniae and other gram‐positive bacteria, which is also regulated by quorum‐sensing peptides. In addition to the mating pheromones and four primary alcohols discussed, there are various examples of quorum‐sensing‐like phenomena and molecules in the literature, indicating that quorum sensing may indeed be as ubiquitous among fungi as it is among bacteria.
1. Efficacy and safety of tetrabamate and chlordiazepoxide in the treatment of the acute or Primary Alcohol Withdrawal Syndrome (PAWS) were assessed during a randomized double blind clinical trial, ...carried out on sixty male alcoholic in-patients. 2. The two drugs were administered four times a day in double dummy conditions, according to a fixed-flexible decreasing dosage schedule (six days basic regimen). 3. Drug efficacy was measured daily throughout the study period using a battery of standard instruments for collecting quantitative clinical, behavioral, psychopathological and laboratory data. Side effects were daily recorded. 4. Tetrabamate was found to be as efficient as chlordiazepoxide in reducing the intensity of the PAWS, improving sleep and vital signs rapidly and alleviating anxiety progressively. 5. Tetrabamate was found particularly beneficial for severe tremor. Psychomotor and mood scores consistently favored tetrabamate, suggesting psychoanaleptic properties of this compound (increased diurnal vigilance). 6. Side effects were minimal with tetrabamate and generally of weak intensity with chlordiazepoxide. 7. The results of this study indicate that tetrabamate may represent a new alternative drug of choice for the therapy of the acute alcohol withdrawal syndrome.
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