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Hermansky–Pudlak syndrome (HPS) is a rare genetic disorder which, in its most common and severe form, HPS‐1, leads to fatal adult‐onset pulmonary fibrosis (PF) with no effective treatment. We evaluated the role of the endocannabinoid/CB1R system and inducible nitric oxide synthase (iNOS) for dual‐target therapeutic strategy using human bronchoalveolar lavage fluid (BALF), lung samples from patients with HPS and controls, HPS‐PF patient‐derived lung fibroblasts, and bleomycin‐induced PF in pale ear mice (HPS1ep/ep). We found overexpression of CB1R and iNOS in fibrotic lungs of HPSPF patients and bleomycin‐infused pale ear mice. The endocannabinoid anandamide was elevated in BALF and negatively correlated with pulmonary function parameters in HPSPF patients and pale ear mice with bleomycin‐induced PF. Simultaneous targeting of CB1R and iNOS by MRI‐1867 yielded greater antifibrotic efficacy than inhibiting either target alone by attenuating critical pathologic pathways. Moreover, MRI‐1867 treatment abrogated bleomycin‐induced increases in lung levels of the profibrotic interleukin‐11 via iNOS inhibition and reversed mitochondrial dysfunction via CB1R inhibition. Dual inhibition of CB1R and iNOS is an effective antifibrotic strategy for HPSPF. [ABSTRACT FROM AUTHOR]

Utilising rabbit corneal endothelial cells (CEC) in three different paradigms, two human FGF1 derivatives (TTHX1001 and TTHX1114), engineered to exhibit greater stability, were tested as proliferative agents. Primary CECs and mouse NIH 3T3 cells treated with the two FGF1 derivatives showed equivalent EC50 ranges (3.3–24 vs.1.9–16. ng/mL) and, in organ culture, chemically lesioned corneas regained half of the lost endothelial layer in three days after treatment with the FGF1 derivatives as compared to controls. In vivo, following cryolesioning, the CEC monolayer, as judged by specular microscopy, regenerated 10–11 days faster when treated with TTHX1001. Over two weeks, all treated eyes showed clearing of opacity about twice that of untreated controls. In all three rabbit models, both FGF1 derivatives were effective in inducing CEC proliferation over control conditions, supporting the prediction that these stabilised FGF1 derivatives can potentially regenerate corneal endothelial deficits in humans. [ABSTRACT FROM AUTHOR]

2-Aminocyclododecan-1-ol and 6(3)-aminodecahydro-1,4-ethanonaphthalen-5(2)-ols (mixture of isomers) were synthesized in two steps via oxidative hydroxybromination of cyclododecene and 1,2,3,4,4a,5,6,8a(1,4,4a,5,6,7,8,8a)-octahydro-1,4-ethanonaphthalines with the system hydrogen peroxide–HBr. In the first step, oxidation of hydrogen bromide with hydrogen peroxide generated intermediate dioxidanium bromide which added to the C=C double bond of the unsaturated substrate to give the corresponding α-bromo alcohols. In the second step, substitution of the bromine atom by amino group in the presence of an alkali afforded α-amino alcohols. [ABSTRACT FROM AUTHOR]

Liquid-phase oxidation of styrene with hydrogen peroxide in the presence of a catalytic system based on (NH4)10W12O41 + Ce(NO3)3 + H3PO4, supported on a microstructured carbon material and treated with an aqueous Н2О2 solution, was studied. The major reaction products are phenyloxirane and benzaldehyde, with phenylacetaldehyde, 1-phenylethane-1,2-diol, and benzoic acid also present. The kinetic relationships of the process were studied, and a kinetic model according to which phenyloxirane is the primary reaction product was suggested. Aldehydes are accumulated by parallel routes: oxidation of phenyloxirane and of its hydrolysis product, 1-phenylethane-1,2-diol. With an increase in the styrene: Н2О2 molar ratio, oxidation of 1-phenylethane-1,2-diol becomes the major pathway of the aldehyde formation. [ABSTRACT FROM AUTHOR]

Conditions for the condensation of cyclopentanone and n-valeric aldehyde to 2-pentylidenecyclopentanone in the presence of an alcoholic solution of piperidine have been developed. The isomerization of the latter in a continuous-flow system over γ-Al2O3 yields 2-pentylcyclopent-2-en-1-one. The condensation of the obtained unsaturated ketones with ethane-1,2-diol in the presence of a heterogeneous catalyst, a natural aluminosilicate (perlite) modified with zirconyl sulfate, has been studied. The optimum conditions for the preparation of the corresponding unsaturated spiroacetals have been found. The synthesized compounds can be used as synthetic fragrances for different purposes. [ABSTRACT FROM AUTHOR]

The results of condensation of C5-C7 alkyl- and cycloalkyl-substituted cyclopentanones with diatomic vicinal alcohols in the presence of polyoxomolybdate modified with gadolinium oxide are considered. Kinetic patterns are investigated and a kinetic model of the process is proposed. It was established that alkyl- and cycloalkyl derivatives of dioxaspironone are formed directly by two parallel-consecutive routes and through the stages of the preparation of the corresponding hemiacetal. The ratio of the rate constants of these routes depends on the composition and structure of the starting ketones and diols. [ABSTRACT FROM AUTHOR]

A method of synthesis of aminobicycloheptanols by the hydroxyhalogenation of bicyclo[2.2.1]- heptene and its alkyl derivatives in a cycloolefin‒oxidant‒hydrogen halide system to induce electrophilic intermediates followed by substitution of the halogen atoms by amino groups of different compositions and structures. It was found that the selectivity of the reaction depends on the formation/consumption rate ratio for the electrophilic intermediate. A high selectivity with respect to hydroxyhalides takes place, when the consumption rate of the latter intermediate is higher than its formation rate. An increase in the pH of the medium becomes higher than 10.5 decreases the yield of amino alcohols and changes the reaction direction due to acceleration of dehydrohalogenation and formation of the corresponding epoxides. [ABSTRACT FROM AUTHOR]

Highly selective one-pot synthesis of N-substituted aminocyclohexanols has been performed by hydroxyhalogenation of the corresponding cyclohexenes with electrophilic reagents formed in situ in the system Н2О2 + HHlg (Hlg = Cl, Br), with subsequent substitution of halogen atoms with amines. Some products were tested as antimicrobial additives to motor oils and cooling lubricants and showed high antibacterial and antifungal activity. [ABSTRACT FROM AUTHOR]

Aminomethylation of bicyclo[2.2.1]heptane-2,3-diol, as well as of its O-allyl- and 5-vinyl derivatives, afforded a series of N-substituted 2-hydroxy(or allyloxy)-3-(aminomethoxy)bicyclo[2.2.1]heptanes which showed high bactericidal and fungicidal activity in lubricating oils. [ABSTRACT FROM AUTHOR]

Induced oxidation of C-C tricyclic bridged olefins synthesized from C-C cyclodiene hydrocarbons using hydrogen peroxide has been studied. It has been shown that phosphomolybdic heteropoly compounds supported on a finely divided carbon material and additionally modified with HBr and CoCO or GdO exhibit high activity in this reaction. Depending on the conditions of the experiments, the main reaction products are the corresponding oxiranes and diols that retain the structure of the reactant hydrocarbons. [ABSTRACT FROM AUTHOR]

Epoxidation of tetracyclododecene bridged hydrocarbons prepared via the [4+2]-condensation of bicyclo[2.2.1]hept-2-ene and its alkyl derivatives with cyclopentadiene in the presence of Н-form of synthetic mordenite has been studied. Phosphorus-molybdenum and phosphorus-tungsten heteropoly compounds doped with Co, Gd, Nd, Ce(4-x)+ ( x = 0, 1) cations as well these compounds deposited on highly disperse carbon material have exhibited high activity in epoxidation of the synthesized hydrocarbons under the action of the HO·CO(NH) adduct. Structures of the new bridged polycyclic epoxides have been elucidated by IR as well as Н and С NMR spectroscopy. [ABSTRACT FROM AUTHOR]

[4+2]-Codimerization of cyclohexa-1,3-diene, cyclopentadiene, and their methyl-substituted derivatives in the presence of H-forms of synthetic mordenite and natural clinoptilolite was studied. Application of zeolites as catalyst decreases the rate of di- and trimerization of cyclopentadiene and its methyl-substituted derivatives, increases the reaction selectivity with respect to their codimers with cyclohexa-1,3-diene and its methylsubstituted derivatives as well as 4-vinylcyclohexene. Epoxidation of the synthesized codimers with the adduct of hydrogen peroxide with urea in the presence of gadolinium- and neodymium-containing phosphorus molybdenum complexes as catalysts has been investigated, and optimal conditions for preparation of diepoxides of tricyclic dienes have been found. [ABSTRACT FROM AUTHOR]

Results are presented from studies of the dehydromethylation (DHM) of methylcyclohexane (MCH) and the simultaneous transformation of straight-run gasoline fractions and methanol on modified forms of mordenite and pentasil in the presence of various hydrogen acceptors (O, CO). High selectivity on xylene isomers is observed for polycationic modifications of HNa-TsVM. On such catalytic systems, the degrees of DHM and dehydrodisproportionation (DHD) of MCH grow with an increase in O-to-CO ratio in the range of 0.05 : (1-1.5), while the degree of its dehydrogenation to toluene is virtually constant. High yields of di- and trimethylbenzenes are achieved in the reactions between methanol and gasoline fractions composed mainly of C-C hydrocarbons at 100-140 °C. The results from this study can be used for straight-run gasoline reforming with the aim of increasing the yield of C-C aromatic hydrocarbons. [ABSTRACT FROM AUTHOR]

The dehydrogenation of 4-vinylcyclohexene in the presence of carbon dioxide results from the activation and breakage of a carbon–hydrogen bond in the substrate molecule using nucleophilic sites (oxygen anions) of the Pt-Ga and Fe-Ga zeolite catalysts. At 485-520 °C, CO 2 participates in the reoxidation of the catalyst surface. [ABSTRACT FROM AUTHOR]

Catalytic oxidation of cyclohexene and its methyl and vinyl derivatives with air oxygen in the presence of Co- and Mo-Co-modified microstructured carbon materials has been studied. Regardless of structure of the parent cycloalkene, cobalt-containing samples at 40-50°C are highly selective towards formation of corresponding hydroperoxides, whereas molybdenum-cobalt containing samples are selective towards cycloalkenes epoxidation. The ratio of epoxide to unsaturated alcohol strongly depends on the structure of the starting substrate. [ABSTRACT FROM AUTHOR]

In promotion of a Pt-Ga-containing pentasil with a binary mixture of REE oxides, a synergism of their effect on the catalyst activity in the reaction of oxidative dehydrogenation of 4-vinylcyclohexene is observed. A kinetic model of the process of oxidative dehydrogenation of 4-vinylcyclohexene is suggested. The model includes a stage-by-stage scheme and the corresponding reaction rate equations. It was found that the accumulation rate of 4-vinylcyclohexene dehydrogenation products is correlated with the isomerization capacity of the catalytic system. [ABSTRACT FROM AUTHOR]

A study was carried out on the oxidative dehydrogenation of 4-vinylcyclohexene to give styrene in the presence of the hydrogen form of pentasil modified by platinum as well as gallium and rare earth oxides. This reaction proceeds through an intermediate step involving migration of the double bond and dehydrogenation of the conjugated dienes to give ethylbenzene. [ABSTRACT FROM AUTHOR]

Oxidation of alicyclic unsaturated hydrocarbons (4-vinylcyclohexene, 5-vinylnorbornene, 5-cyclohexenylnorbornene, and 5-vinylbicyclooctene) with 30% hydrogen peroxide solutions and percarbamide is studied. Reaction was carried out at 40-70°C in the presence of heterogenized peroxocomplex compounds of molybdenum and tungsten formed 'in situ' in the reaction of metal oxohalides with HPO, nano-dimensional particles of carbon material, and hydrogen peroxide. Main oxidation products of alicyclic diene hydro-carbons are the corresponding unsaturated epoxides and diols. Depending on the reaction condition their ratio varies in a wide range. [ABSTRACT FROM AUTHOR]

Optimal conditions were found for induced hydroxyhalogenation of cyclic dienes (tetrahydroindene, 4-vinylcyclohexene and 5-vinyl- and 5-cyclohexenylbicyclo[2.2.1]hept-2-enes) in the system [MHlg-HA or HHlg]-HO (or NaClO). Dehydrohalogenation of the chloro- and bromohydrins thus obtained with powdered potassium carbonate gave the corresponding diepoxy derivatives, and their hydrolysis led to mixtures of stereoisomeric tetrahydric alcohols. [ABSTRACT FROM AUTHOR]

The results of studies on the oxidative dehydrogenation of 4-vinylcyclohexene to ethylbenzene and styrene and ethylbenzene to styrene on nanocomposite systems prepared by the immobilization of carbon nanoparticles on the H forms of zeolites and the modification of the resulting samples with platinum, gallium, and gadolinium are given. The activities of these catalysts are compared, and the synergism of the action of zeolite and carbon nanoparticles under the conditions of dehydrogenation is established. The immobilization of carbon nanoparticles into zeolite matrices contributes to an increase in their activity and stability and also to a decrease in the reaction temperature. The high yields of 4-vinylcyclohexene and ethylbenzene dehydrogenation products are reached at 425 and 470°C, respectively. [ABSTRACT FROM AUTHOR]

The condensation of C-C alkyl- and cycloalkylcyclopentanones and cyclohexanones with 1,2-ethane-, 1,2-propane-, and 1,3-butanediols in the presence of heterogenic acid catalysts provided new representatives of spiroacetals. The highest yields of reaction products were obtained in the presence of phosphomolybdic heteropolyacid additionally modified with cobalt and bromine, and also in the presence of the chlorinated cationite KU-23 at 110-130°C. The synthesized spiroacetals possess the jasmine and menthol-wooden fragrance of various tinges. [ABSTRACT FROM AUTHOR]

The reaction of catalytic oxidation of C-C alkyl- and cycloalkylcyclopentanones and -cyclohexanones to lactones in a pseudohomogeneous system without the participation of phase transfer agents was investigated. It was established that the catalytic systems prepared on the basis of molybdenum and tungsten blue (MeOBr, where Me = Mo, W, n = 1, 2, m = 2, 3) and HPO deposited on powdered activated carbon AG-3 at 40-60°C, at 5-6 h duration exhibit a high selectivity in the reaction of nucleophilic addition of oxygen to the ketones with the formation of the valero- and caprolactones. [ABSTRACT FROM AUTHOR]

Mathematical modeling and theoretical optimization have been carried out for methylcyclohexane dehydroalkylation with methanol over platinum-, gallium-, and phosphorus-containing pentasil in a sectionalized adiabatic reactor with intermediate heat removal and sectional methanol feeding. [ABSTRACT FROM AUTHOR]

Mathematical modeling and theoretical optimization have been carried out for methylcyclohexane dehydroalkylation with methanol over platinum-, gallium-, and phosphorus-containing pentasil in a sectionalized adiabatic reactor with intermediate heat removal and sectional methanol feeding. [ABSTRACT FROM AUTHOR]

Liquid-phase oxidation of cyclohexene, methylcyclohexene isomers, and norbornene with a 30% solution of hydrogen peroxide in a pseudohomogeneous system involving highly dispersed compounds of Group-VIb and -VIIIb metals supported by nanosize carbon particles was studied. [ABSTRACT FROM AUTHOR]

The oxidative dehydrogenation reaction of 4-vinylcyclohexene (4-VCH) in the presence of a pentasil zeolite (TsVM) modified by platinum, gallium, gadolinium, and potassium was investigated. The influence of the nature of the modifiers on the progression of the reaction and the yields of the desired product, ethylbenzene and styrene, was established. It was found that the conversion of 4-VCH into ethylbenzene and styrene proceeds along two parallel routes, the oxidative dehydroisomerization and dehydrogenation of the reactant hydrocarbon. Conditions for the maximal yield of styrene on potassium hydroxide-promoted Pt,Ga,Gd/HNa-TsVM were determined. [ABSTRACT FROM AUTHOR]

The reactions of induced hydroxyhalogenation of alkylnorbornenes with the use of a mixture of aqueous solutions of hydrochloric or hydrobromic acids (or sodium, potassium and cobalt bromides) and hydrogen peroxide or sodium hypochloriteare are studied. The reaction are established to proceed through the addition at the double bond of the ring of the electrophilic reagent HOBr or HOCl formed in situ yielding of cis-vicinal halohydrines. By dehydrohalogenation of the latter in the presence of alkali are obtained endo-6-alkyl- endo-3-oxatricyclo[3.2.11.5.02.4]octanes and by their oxidation are synthesized respective haloketones in a high yield. [ABSTRACT FROM AUTHOR]

Abstract  Synthesis of C6–C7 alicyclic diols was studied by a catalytic oxidation of cyclohexene, norbornene and their methyl derivatives in the presence of heterogenized molybdenum-containing catalysts. By a triple condensation of the diols with formaldehyde and secondary amines a synthesis of their aminomethylated derivatives with various substituents at nitrogen atom was examined. Antimicrobial properties of the synthesized amino alcohols in M-10 oil as additives with fungicidal and bactericidal activities were studied. [ABSTRACT FROM AUTHOR]

The induced halogenation and hydroxyhalogenation of alkyl cyclohexenyl ketones in a system [MHlg + HHlg or HHlg]-H2O2 or in NaOCl was performed and optimum reaction conditions were established. Under mild conditions the electrophilic addition of the halogen or the acid occurred at the multiple bond of the ring with the formation of the corresponding dihalo or hydroxyhalo derivatives of cycloaliphatic ketones. From the compounds obtained epoxy- and dioxyketones of aliphatic series were prepared. Chloro(bromo)hydrins of ketones from the alkylcyclohexane series and oxiranes based thereon are reactive compounds and can be employed as synthons in the organic synthesis. [ABSTRACT FROM AUTHOR]

Hypohalogenation of norbornenes containing a triple bond and various functional groups in the side chain was performed using mixtures of aqueous solutions of hydrochloric or hydrobromic acid (or sodium or potassium bromide) and hydrogen peroxide. The reaction was found to involve addition of electrophilic reagent generated in situ (HOBr or HOCl) at the endocyclic double bond with formation of the corresponding halohydrins. The latter underwent dehydrohalogenation by the action of alklai to give exo-5,6-epoxybicyclo[2.2.1]-heptane derivatives in high yields. Kinetic relations holding in the hypobromination process were established, and the initial rates and activation parameters were calculated. [ABSTRACT FROM AUTHOR]

Hypohalogenation of 2-methylhex-5-en-3-yn-2-ol, 2-methylhept-6-en-3-yn-2-ol, and their methyl ethers at 303–328 K with hydrochloric or hydrobromic acid in the presence of hydrogen peroxide involves only the double bond to produce the corresponding halohydrins in fairly high yields. Kinetic parameters of these reactions were determined, and the allylacetylenic alcohol and its methyl ether were found to be more reactive than their vinylacetylenic analogs. Acetylenic halohydrins and oxiranes derived therefrom were shown to be quite reactive compounds which may be used as building blocks in organic synthesis. [ABSTRACT FROM AUTHOR]

Bromination of 1-arylbut-2-enes in the system [HBr or NaBr (KBr)-HX]-H2O2 (or NaOCl) under relatively mild conditions leads to electrophilic addition of bromine or hypobromous acid at the side-chain double bond. Under more severe conditions, the process is accompanied by bromination of the aromatic ring. Treatment of the title compounds with peroxy acids (RCOOH-H2O2) gives the corresponding epoxy derivatives which react with HBr and oxygen-containing nucleophiles to produce α-bromo alcohols, diols, and diol acetates. [ABSTRACT FROM AUTHOR]

The reactions of dehydroalkylation of methylcyclohexane, ethylcyclohexane, and methylcyclohexene isomers and toluene alkylation with methanol on platinum-and gallium-modified pentasil in the presence of an O2-CO2 mixture was studied. Optimum conditions were found for the one-step dehydroalkylation of methylcyclohexane on the ring. Under these conditions, the degree of conversion of methylcyclohexane and methylcyclohexene isomers into xylene isomers is above that of toluene alkylation to afford xylene. According to the discussed reaction mechanism, the dehydroalkylation of cyclohexane hydrocarbons on Pt, Ga-pentasil involves both the steps of formation of unsaturated intermediates and toluene in status nascendi. [ABSTRACT FROM AUTHOR]

Abstract  The features of induced bromination of aromatic hydrocarbons in the NaBr(KBr)-HX-H2O2(NaOCl) system were studied. [ABSTRACT FROM AUTHOR]

Induced bromination of aromatic compounds was performed in the system NaBr-acid-H2O2. Optimum conditions of performing this process were found, and its kinetics and mechanism were studied. The bromination was found to occur by both bromine in the nascent state and hypobromous acid. The formation of bromoaromatic compounds by substitution for hydrogen atoms in only aromatic ring is a limiting stage of the process. [ABSTRACT FROM AUTHOR]

Induced bromination of aromatic compounds in a system MBr-acid-NaOCl was studied. Optimum conditions of the process were developed, kinetics of the reactions were investigated, and the process mechanism was suggested. The bromination occurs both with the bromine in statu nascendi and with the hypobromous acid by hydrogen substitution exclusively in the aromatic ring. [ABSTRACT FROM AUTHOR]

The kinetics of oxidative dehydrodisproportionation of methylcyclohexane in the presence of H-TsVM zeolite (SiO : AlO = 30) modified with gallium and gadolinium oxides was studied. A kinetic model fairly adequately describing this process in a wide temperature range was proposed. The kinetic constants of some oxidation reactions were determined. [ABSTRACT FROM AUTHOR]

New alicyclic esters were synthesized by addition at heating of aliphatic monocarboxylic saturated acids C1-C4 to exo-5-phenyl-, exo-5-cyclohexyl-, and exo-5-(cyclohex-3-enyl)bicyclo[2.2.1]hept-2-enes. Among the esters obtained the acetates has more pleasant odor with fruit tint, and they may be used as a component of synthetic perfumes. [ABSTRACT FROM AUTHOR]