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At least 19 recordsLinked to original sources
PubMed1977

Azabicycloalkanes as analgetics. 3. Structure-activity relationships of 1-phenyl-6-azabicyclo[3.2.1]octanes and absolute stereochemistry of (+)-1-(3-hydroxyphenyl)-6-methyl-6-azabicyclo[3.2.1]octane and its 7-endo-methyl derivative.

A series of 53 1-phenyl-6-azabicyclo[3.2.1]octanes (1) has been tested for their analgetic and narcotic antagonist activities. Structure-activity relationships were investigated by varying the structural parameters. The most interesting compound in this series, the 1-(3-hydroxphenyl)-6,7-dimethyl derivative 8, shows the profile of a well-balanced antagonist-analgesic agent with a very mild physical dependence capacity. The absolute stereochemistry of its active enantiomer [(+)8] was established by the x-ray study and the chemical transformation to the phenylmorphan [(+)-II]. (+)-8 was stereochemically correlated also with the active enantiomer of the 7-demethyl derivatives [(+)-7] by chemical transformation and CD measurement. Certain structural and stereochemical correlations between these compounds (7 and 8) and other known antagonist-analgetics are discussed.

Analgesics↗
PubMed1976

[Electrogenic function of submitochondrial particles at the water-octane interphases].

Studies on submitochondrial particles (SMP) preparation showed that in the sourse of the redox reactions at the octane-water interface, catalyzed by SMP enzymes, the charges are transferred from the aqueous to the octane phase. The effects were detected by a shift of the Volta potential, using the vibrating electrode method. In the presence of 2-N-methyl-amino-1,4-naphthoquinone in octane, acting as electron acceptor, the negative charges were transferred from water to octane following the oxidation of NADH, succinate and ascorbate. The charging of the octane phase was sensitive to the inhibitors of the respiratory chain, e. g. rotenone, antimycin and cyanide. In the presence of 2,4-DNP in octane, acting as a proton acceptor, the oxidation of NADH and succinate by ferricyanide, catalyzed by CMP in the presence of antimycin and cyanide correspondingly, was followed by a transfer of positive charges from water to octane. The positive charging of the octane phase, coupled with NADH oxidation, was found insensitive to rotenone, and that coupled with succinate oxidation, was completely inhibited by antimycin. The positive charging of the octane phase was also observed during the reverse transhydrogenase reaction, catalyzed by SMP at the division of the phases. The effect was inhibited by palmitoyl-CoA.

Alkanes↗
PubMed1973

Genetic regulation of octane dissimilation plasmid in Pseudomonas.

The enzymes responsible for the oxidation of n-octane to octanoic acid or beyond in Pseudomonas oleovorans are octane inducible and are coded by genes borne on a transmissible extrachromosomal element. The octane to octanoate enzymes induced by octane are repressed by octanol. The chromosome also carries genes coding octanol oxidation enzymes that, in contrast, are induced by octanol, not by octane. The octane plasmid has been transferred from P. oleovorans to several other fluorescent Pseudomonas species. In exconjugants, the presence of both octane and camphor plasmids enhances their segregation rate.

Alcohol Oxidoreductases↗
PubMed1989

The fate of inhaled octane and the nephrotoxicant, isooctane, in rats.

To determine if inhaled nephrotoxic branched and nonnephrotoxic straight chain alkanes differ substantially in their biological fate, male F344 rats were exposed to 14C-labeled isooctane and octane vapors at approximately 1 and 350 ppm by the nose-only mode for 2 hr. Radioactivity in exhalant, urine, and feces was determined for 70 hr post exposure, after which residual radioactivity in the rat carcasses was determined. Absorbed [14C]isooctane equivalents were eliminated almost exclusively via the kidneys, while absorbed [14C]octane equivalents were excreted about equally via the kidneys and as 14CO2. Kidney excretion of isooctane-introduced 14C was protracted over the entire 70 hr postexposure observation period whereas for octane-introduced 14C, kidney excretion was essentially complete after 10-20 hr. About 5% of the [14C]octane equivalents inhaled at 1 ppm remained in the carcass 70 hr after inhalation exposure. Two percent of the [14C]octane equivalents inhaled at 350 ppm and 1-2% of the [14C]isooctane equivalents inhaled at either 1 or 350 ppm remained in the carcass 70 hr after inhalation exposure. The different patterns of excretion of metabolites of isooctane compared to octane may be a factor affecting the differences in nephrotoxicity between these two compounds.

Acute Kidney Injury↗
PubMed1977

A study on the distribution of methylchloroform and n-octane in the mouse during and after inhalation.

The distribution of methylchloroform and n-octane, respectively, in the blood, liver, kidney, and brain of mice was studied at different inspired air concentrations and after different exposure times. The air concentration varied between 10 and 10,000 ppm; and the exposure time, between 0.5 and 24 h. The resulting solvent concentrations in kidney and brain were about the same, but the liver concentrations were usually somewhat higher for both solvents. There was a linear dependence between inspired air concentration and tissue concentrations at fixed exposure times. A correlation between blood and organ concentrations was observed in animals exposed at different inhalation air concentrations but not in animals exposed only at one fixed concentration. The ratios between the concentrations of the solvents in the organs and blood were higher for n-octane than for methylchloroform. The ratios increased as the exposure concentration increased for all organs studied in the case of n-octane but only for the liver in the case of methylchloroform. When the exposure dose, i.e., inspired air concentration X time, was generated in different ways, a high concentration during a short exposure resulted in a ten times higher organ concentration than a low concentration during a long exposure. The liver, kidney, and brain concentrations generally did not differ more than twice between methylchloroform and n-octane after exposure of the same concentration and duration. The blood concentration, however, was much less in n-octane exposed animals than in methylchloroform exposed ones. A pharmacokinetic model with both uptake and elimination of the first order fitted the empirical data better for methylchloroform than a model with zero order uptake and first order elimination. Postexposure concentrations of methylchloroform were linear in a semilog graph. A one-compartment pharmacokinetic model was in accordance with the experimental data for methylchloroform. For n-octane, however, at least a two-compartment model must be assumed.

Aerosols↗
PubMed1982

Metabolism in the rat of potassium DL-octan-2-sulphate, a secondary alkyl sulphate.

1. The metabolism of potassium [2-14C]octan-2-sulphate and potassium octan-2-[35S]sulphate was investigated in the rat. Following oral administration, the bulk of the radioactivity was eliminated in the urine within 24 h. 2. Whole-body radioautography showed the liver to be the principal site of tissue accumulation of radiolabel following administration of 14C- or 35S-labelled DL-octan-2-sulphate. 3. Octan-2-sulphate was extensively degraded in vivo. The major urinary components are five sulphate estes, present in urine in essentially the same proportions regardless of label. The relative proportions of radioactivity associated with the urinary components showed considerable differences between male and female rats. 4. Three of the components have been identified as butanoate-3-sulphate, hexanoate-5-sulphate and octanoate-7-sulphate. The remaining metabolite was tentatively identified as an aldehyde derivative of octan-2-sulphate, a possible intermediate in the formation of octanoate-7-sulphate.

Animals↗
PubMed1975

An examination of octanol and octanal metabolism to octanoic acid by horse liver alcohol dehydrogenase.

The kinetics of the horse liver alcohol dehydrogenase (alcohol: NAD+ oxidoreductase EC 1.1.1.1) catalyzed metabolism of octanol and octanal to octanoic acid have been examined. On incubation of octanol with horse liver alcohol dehydrogenase in the presence of NAD+, NADH as well as octanal and octanoic acid were seen as the initial products. However, on continued incubation, the octanal concentration progressively decreased to where only negligible quantities were present in the incubation after 10 min. The production of NADH was biphasic. An initial phase was followed in about 2 min with a slower but linear rate of NADH production. The production of octanoic acid was approximately linear throughout the 10 min incubation period. Since octanal is an intermediate in the oxidation of octanol to octanoic acid, the ability of semicarbazide to inhibit the metabolism of octanol to octanoic acid was examined. At a concentration of semicarbazide which was 63 times the concentration of octanol in the incubation media, the rate of formation of octanoic acid was inhibited by only 30%. The results of these experiments suggest that in the oxidation of octanol to octanoic acid a portion of the octanal formed from octanol is not released from the enzyme but, in the presence of NAD+, is oxidized to octanoic acid.

Alcohol Oxidoreductases↗
PubMed1978

[Bicyclic piperazine homologues XIV (1). Synthesis and analgesic activity of 3,8-diaza-bicyclo[3.2.1.] octane derivatives].

The synthesis of two new series of 3,8-diazabicyclo [3.2.1] octane derivatives is described. The first series includes some 3-(or 8)-allyl and 3-(or 8)-(3,3-dimethylallyl) derivatives of 3,8-diazabicyclo [3.2.1] octane and 3,8-diazabicyclo [3.2.1] octane-2-one. The second series includes some esters and carbamates of 3-(3-hydroxy-3-methyl)butyl-3,8-diazabicyclo [3.2.1] octane. Two new 3,8-diazabicyclo [3.2.1] octane derivatives structurally related to propoxyphene are also described. Some pharmacological data of these compounds are reported.

Analgesics↗
PubMed1990

Intrinsic isotope effects suggest that the reaction coordinate symmetry for the cytochrome P-450 catalyzed hydroxylation of octane is isozyme independent.

The mechanism of the omega-hydroxylation of octane by three catalytically distinct, purified forms of cytochrome P-450, namely, P-450b, P-450c, and P-450LM2, was investigated by using deuterium isotope effects. The deuterium isotope effects associated with the omega-hydroxylation of octane-1,1,1-2H3, octane-1,8-2H2, and octane-1,1,8,8-2H4 by all three isozymes were determined. From these data the intrinsic isotope effects were calculated and separated into their primary and secondary components. The primary intrinsic isotope effect for the reaction ranged from 7.69 to 9.18 while the secondary intrinsic isotope effect ranged from 1.13 to 1.25. Neither the primary nor secondary isotope effect values were statistically different for any of the isozymes investigated. These data are consistent with a symmetrical transition state for a mechanism involving initial hydrogen atom abstraction followed by hydroxyl radical recombination which is essentially independent of the specific isozyme catalyzing the reaction. It is concluded that (1) in general the porphyrin-[FeO]3+ complex behaves as a source of a triplet-like oxygen atom, (2) the regioselectivity for the site of oxidation is dictated by the apoprotein of the specific isozyme of cytochrome P-450 catalyzing the reaction, and (3) the maximum primary intrinsic isotope effect for any cytochrome P-450 catalyzed oxidation of a carbon center is about 9, assuming no tunneling effects.

Cytochrome P-450 Enzyme System↗
PubMed1995

Growth on octane alters the membrane lipid fatty acids of Pseudomonas oleovorans due to the induction of alkB and synthesis of octanol.

Growth of Pseudomonas oleovorans GPo1, which contains the OCT plasmid, on octane results in changes in the membrane phospholipid fatty acid composition. These changes were not found for GPo12, an OCT-plasmid-cured variant of GPo1, during growth in the presence or absence of octane, implying the involvement of OCT-plasmid-encoded functions. When recombinant strain GPo12(pGEc47) carrying the alk genes from the OCT plasmid was grown on octane, the cells showed the same changes in fatty acid composition as those found for GPo1, indicating that such changes result from induction and expression of the alk genes. This finding was corroborated by inducing GPo12(pGEc47) with dicyclopropylketone (DCPK), a gratuitous inducer of the alk genes. Further experiments showed that the increase of the mean acyl chain length of fatty acids is related to the expression of alkB, which encodes a major integral membrane protein, while the formation of trans unsaturated fatty acids mainly results from the effects of 1-octanol, an octane oxidation product.

1-Octanol↗
PubMed1983

Studies on the utilization of octane by algae.

The objective of this study was to investigate the influence of various octane concentrations on a mixed culture of Scenedesmus obliquus, Chlorella vulgaris and Oscillatoria sp. and the ability of these algae to utilize octane as the sole source of organic carbon in the medium. The same investigations were carried out for a mixed culture consisting of algae and the strain Acinetobacter calcoaceticus, and for A. calcoaceticus alone. The results obtained show that all of the strains under study, both algal and bacterial, can grow even at high octane concentrations and that they are able to utilize octane.

Acinetobacter↗
PubMed1995

Single crystal X-ray structures of the two 4-heptadecyl derivatives of (1R,5S)-3,6,8-trioxabicyclo[3.2.1]octane.

The single crystal structures of the two diastereomeric 4-heptadecyl derivatives of (1R,5S)-3,6,8-trioxabicyclo[3.2.1]octane have been determined by X-ray diffraction to be (1R,4R,5S)-heptadecyl-3,6,8-trioxabicyclo[3.2.1]octane (I) and (1R,4S,5S)-4-heptadecyl[3,6,8-trioxabicyclo[3.2.1]octane (II), respectively, which have an exo or axial 4-heptadecyl group, and an endo or equatorial 4-heptadecyl group, respectively. The structures of I and II had been suggested by their phase-sensitive 2D NOESY 1H-NMR spectra, but are now established unambiguously. These optically pure non-ionic lipid-like amphipathic molecules (I and II) represent the first 3,6,8-trioxabicyclo[3.2.1]octanes for which single crystal structures have been solved. Crystals of both isomer I and isomer II were orthorhombic with space group P2(1)2(1)2(1), and had unit cell dimensions of a = 9.586, b = 43.14, c = 5.289 A, and a = 7.34, b = 51.8, c = 5.636 A, respectively. The structures of I and II were both solved by using direct methods to R = 0.045 and R = 0.086, respectively. Both I and II pack in stacked bilayers with interdigitating and tilting hydrocarbon chains. The molecular and hydrocarbon cross sections are I: S = 50.70 A2, sigma = 19.00 A2; and II: S = 41.37 A2, sigma = 18.26 A2.

Bridged Bicyclo Compounds, Heterocyclic↗
PubMed1975

[Bicyclic analogs of piperazine. XIII (1). Derivatives of 3,8-diazabicyclo[3.2.1]octane with potential anti-inflammatory activity].

The Authors describe the synthesis of some 8-acyl-3-methyl-3,8-diazabicyclo[3.2.1]octanes and 3-acyl-8-methyl-3,8-diazabicylo[3.2.1] octanes. The compounds were prepared by acylation of the corresponding methyl derivatives with the purpose of obtaining antiinflammatory compounds. The synthesis of some 3-alkyl-8-propionyl-3,8-diazabicylo[3.2.1]octanes is also described. These compounds were prepared in analogy with some 8-pripionyl-3,8-diazabicyclo[3.2.1]octanes endowed with high analgesic and antiinflammatory activity.

Anti-Inflammatory Agents↗
PubMed1980

n-Octane and n-nonane induced alterations in xenobiotic metabolising enzyme activities and lipid peroxidation of rat liver.

After 2 and 7 days on n-octane and n-nonane administration (intraperitoneally) to female albino rats, alterations in the levels of hepatic xenobiotic metabolising enzyme activities and TBA reactants were observed. Fifty to eighty per cent reduction in the specific activities of benzo[a]pyrene hydroxylase, benzphetamine-N-demethylase, p-nitroanisole-O-demethylase and glutathione-S-transferase were observed. Cytochrome P-450 and free sulfhydryl contents of liver were also decreased significantly after 7 days treatment on n-octane and n-nonane. A 2- and 3- fold increase in liver lipid peroxidation estimated as TBA reactants was observed in the animals treated for 2 or 7 days with n-octane or n-nonane.

Alkanes↗
PubMed1986

The metabolism of n-octane in Fischer 344 rats.

The urinary metabolites of n-octane in Fischer 344 rats given the hydrocarbon by gavage included 2-octanol, 3-octanol, 5-oxohexanoic acid, and 6-oxoheptanoic acid. The sex of the animals influenced the relative amounts of metabolites formed. Analyses were performed by gas-liquid chromatography (GC) and gas-liquid chromatography/mass spectrometry (GC/MS). This is the first reported finding of keto acids in hydrocarbon oxidative metabolism. No kidney damage was found as a result of n-octane dosing although the 2,2,4-trimethylpentane (iso-octane) isomer does cause kidney lesions in male rats.

Administration, Oral↗
PubMed1981

Oxidase determination of plasma cholesterol as cholest-4-en-3-one using iso-octane extraction.

Cholesterol esters in 20 microliter of plasma are hydrolysed with hot ethanolic KOH. Preformed cholesterol and cholesterol released by hydrolysis is reacted with cholesterol oxidase to form hydrogen peroxide and cholest-4-en-3-one, which is extracted from alkaline 50% v/v ethanolic solution with iso-octane. The absorbance of the ketone in iso-octane at the 232 nm peak is used to measure the cholesterol originally present. Plasma blanks obtained by omitting the cholesterol oxidase from the reagent shown negligible absorbance even when samples are grossly icteric, lipaemic, or haemolysed. The test is carried out in a single glass screw-capped tube, and the absorbance given by a sample containing 6.25 mmol/1 cholesterol is approximately 0.44, corresponding to a molar absorbance of approximately 17 500. The conversion of cholesterol to cholest-4-en-3-one is stoichiometric, and the absorbance of the iso-octane layer is stable for at least 48 hours. A single determination occupies 30 minutes, 30 samples can be analysed in 1 1/2 hours.

3-Hydroxysteroid Dehydrogenases↗
PubMed1990

omega-Dialkylaminoalkyl ethers of 6-(benzyl or phenyl)-1,3,3-trimethyl-2-oxabicyclo [2.2.2]octan-6-ol with platelet antiaggregating and local anesthetic activities.

The synthesis of 1,3,3-trimethyl-6-phenyl-2-oxabicyclo[2.2.2]octan-6-ol 2 and 6-benzyl-1,3,3-trimethyl-2-oxabicyclo[2.2.2]octan-6-ol 3 starting from (+)-1,3,3-trimethyl-2-oxabicyclo[2.2.2]octan-6-one and phenylmagnesium bromide or benzylmagnesium chloride, respectively, is described. Alcohols 2 and 3 gave a series of omega-dialkylaminoalkyl ethers 4 by reaction as sodium salts with omega-chloroalkyldialkylamines in toluene solution. Some compounds 4, in particular those derived from alcohol 2, showed a strong platelet antiaggregating activity in vitro, superior to that of acetylsalicylic acid, as well as in general an appreciable local anesthetic activity and a weak sedative effect in mice.

Anesthesia↗