BACKGROUND AND OBJECTIVES: Using n-aliphatic alcohols whose physical properties change gradually as their length increases, we investigated the changes of olfactory threshold and trigeminal pungency threshold with the increase of carbon chain length. MATERIALS AND METHOD: Olfactory and trigeminal pungency thresholds were measured in ethanol (C2), 1-butanol (C4), 1-hexanol (C6) and 1-octanol (C8) in 40 normal adults using a two-alternative forced-choice modified by the ascending method of limit (CCCRC) test. Plastic bottles with 30 ml of four n-aliphatic alcohols were diluted threefold successively by mineral oil. Plastic bottles containing only mineral oil were used as controls. RESULTS: The olfactory and trigeminal pungency thresholds decreased and the ratio of olfactory threshold/trigeminal pungency threshold increased with the length of carbon chain in n-aliphatic alcohols. The correlation coefficients among olfactory thresholds in each alcohol were higher than those among trigeminal pungency thresholds. CONCLUSION: Alcohol with long carbon chains showed low olfactory and trigeminal pungency thresholds, indicating that high lipid solubility is an important factor in olfaction and trigeminal chemosensitivity.
1-Butanol ; 1-Octanol ; Adult* ; Alcohols* ; Carbon* ; Ethanol ; Humans ; Mineral Oil ; Plastics ; Smell ; Solubility

This paper is to establish a reversed-phase ion-pair chromatography (RP-IPC) method for universal estimation of the octanol/water partition coefficients (logP) of a wide range of structurally diverse compounds including acidic, basic, neutral and amphoteric species. The retention factors corresponding to 100% water (logk(w)) were derived from the linear part of the logk'/phi relationship, using at least four isocratic logk' values containing different organic compositions. The logk(w) parameters obtained were close to the corresponding logP values obtained with the standard "shake flask" methods. The mean deviation for test drugs is 0.31. RP-IPC with trifluoroacetic acid as non classic ion-pair agents can be applicable to determine the logP values for a variety of drug-like molecules with increased accuracy.
1-Octanol ; chemistry ; Chromatography, Reverse-Phase ; methods ; Hydrogen-Ion Concentration ; Octanols ; chemistry ; Trifluoroacetic Acid ; Water ; chemistry

OBJECTIVETo study the chemical constituents of the volatile oil from Radix Cudramiae.

METHODThe oil was obtained by steam distillation. The chemical compositions were separated and identified by GC-MS. The relative contents in the oil were determined by area nomalization.

RESULTSixty-four compounds were obtained from Radix Cudramiae. The relative contents of twenty-three compounds were more than 1%. The highest relative content was L-linalool (9.852%).

CONCLUSIONSixty-four compounds characterized by GC-MS analysis were obtained from Radix Cudramiae for the first time.

1-Octanol ; analysis ; Gas Chromatography-Mass Spectrometry ; Monoterpenes ; analysis ; Moraceae ; chemistry ; Oils, Volatile ; chemistry ; isolation & purification ; Plant Roots ; chemistry ; Plants, Medicinal ; chemistry ; Sesquiterpenes ; analysis

Bicyclol with benzyl alcohol structure, is a poorly water-soluble drug, used for the treatment of chronic hepatitis B. To increase the drug solubility and oral bioavailability, a Bicyclol-phospholipid complex was studied on its preparation, formation mechanism, and the influence on drug physicochemical properties and oral absorption. The complex was prepared by a solvent evaporation method. The optimal formulation was selected by orthogonal experimental design, and a reasonable evaluating method of the complexation rate was established. Various methods, such as differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and 31P nuclear magnetic resonance (31P-NMR), were used to explore the phase state and formation mechanism of the complex. The solubility of drug in complex was investigated in water/n-octanol. Preliminary study of its absorption and liver tissue distribution in rats was also carried out. The results showed that Bicyclol and phosphatidylcholine can be complexed entirely in the molar ratio 1 : 2. Bicyclol was dispersed in phospholipids as amorphous state. They were combined by intermolecular hydrogen bond due to charge transfer effect which occurred between the two polarities of the double bond between phosphorus and oxygen (P=O) of phosphatidylcholine and benzalcohol group of Bicyclol. The solubility of the complex compared to the active pharmaceutical ingredient (API) was effectively enhanced 5.75 times in water and 7.72 times in n-octanol, separately. In addition, drug concentrations were also enhanced 43 times in plasma and 13 times in liver with one hour after administering the complex to rats via oral gavage. All of these indicated that Bicyclol with benzalcohol group can interact with phospholipids to form complex, improving drug's physicochemical properties, thus further increasing its absorption and target tissue distribution. This study also provided theoretical reference for the research of other benzalcohol derivatives complexed with phospholipids.
1-Octanol ; Animals ; Biological Availability ; Biphenyl Compounds ; pharmacokinetics ; Calorimetry, Differential Scanning ; Chemistry, Pharmaceutical ; Phospholipids ; pharmacokinetics ; Rats ; Solubility ; Spectroscopy, Fourier Transform Infrared ; Tissue Distribution ; X-Ray Diffraction

The HPLC and TLC retention, n-octanol/water partition coefficients (log Kow), bioconcentration factors, and acute toxicity data of 29 heteroatomic polycyclic aromatic hydrocarbons and 7 parent polycyclic aromatics were determined experimentally. For the same set of compounds, molecular weights, fragmental log Kow values, and molecular connectivities were calculated. Quantitation of the mathematical relationships between the variables was used to validate the predictive potential of various parameters. The importance of log Kow in predictive studies is highlighted. It is concluded that the internal concentration of a pollutant in the organism should be used as a parameter in future QSAR work.
1-Octanol ; Animals ; Chromatography, High Pressure Liquid ; Chromatography, Thin Layer ; Daphnia ; drug effects ; Ecology ; Environmental Pollution ; prevention & control ; Octanols ; Photobacterium ; drug effects ; Poecilia ; metabolism ; Polycyclic Compounds ; metabolism ; toxicity ; Regression Analysis ; Solubility ; Structure-Activity Relationship ; Water

OBJECTIVETo determine the equilibrium solubility of pulchinenosiden D in different solvents and its n-octanol/water partition coefficients.

METHODCombining shaking flask method and high performance liquid chromatography (HPLC) to detect the n-octanol/water partition coefficients of pulchinenosiden D, the equilibrium solubility of pulchinenosiden D in six organic solvents and different pH buffer solution were determined by HPLC analysis.

RESULTn-Octanol/water partition coefficients of pulchinenosiden D in different pH were greater than zero, the equilibrium solubility of pulchinenosiden D was increased with increase the pH of the buffer solution. The maximum equilibrium solubility of pulchinenosiden D was 255.89 g x L(-1) in methanol, and minimum equilibrium solubility of pulchinenosiden D was 0.20 g x L(-1) in acetonitrile.

CONCLUSIONUnder gastrointestinal physiological conditions, pulchinenosiden D exists in molecular state and it has good absorption but poor water-solubility, so increasing the dissolution rate of pulchinenosiden D may enhance its bioavailability.

1-Octanol ; chemistry ; Acetonitriles ; chemistry ; Biological Availability ; Chromatography, High Pressure Liquid ; methods ; Drugs, Chinese Herbal ; chemistry ; pharmacokinetics ; Gastrointestinal Tract ; metabolism ; Humans ; Hydrogen-Ion Concentration ; Intestinal Absorption ; Kinetics ; Methanol ; chemistry ; Pulsatilla ; chemistry ; Solubility ; Solvents ; chemistry ; Water ; chemistry

OBJECTIVETo measure the 96h-LC50 values of 32 substituted benzenes to the carp and to study the relationship between quantitative structure-activity and structural parameters of chemicals.

METHODSThe acute toxicity values of 32 substituted benzenes to the carp were determined in a semistatic test. The energy of the lowest unoccupied molecular orbital, and the highest occupied molecular orbital, the dipole moment and the molecular weight of substituted benzenes were calculated by the quantum chemical method MOPAC6.0.

RESULTSThe range of the toxicity of studied compounds was broad, and the most toxic compound was pentachlorophenol, while the least toxic compound was 4-methylaniline. By the stepwise regression analyses, a series of Quantitative structure-activity relationships (QSAR) equations were derived from all compounds and subclasses. The equation log1/LC5o=0.759logP + 2.222 (R2 (adj)=0.818) was found to fit well and the average predicted percentage error was 6.16%.

CONCLUSIONThe toxicity of anilines and phenols to the carp could be modeled well by logP alone, whereas the toxicity of the halogenated benzenes and nitrobenznes not containing hydroxyl or amino group can be controlled by hydrophobic and electronic factors.

1-Octanol ; chemistry ; Aniline Compounds ; toxicity ; Animals ; Benzene Derivatives ; toxicity ; Carps ; Hydrophobic and Hydrophilic Interactions ; Lethal Dose 50 ; Models, Chemical ; Molecular Weight ; Phenols ; toxicity ; Quantitative Structure-Activity Relationship ; Water ; chemistry ; Water Pollutants, Chemical ; toxicity