Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Allylbenzene Derivatives”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Metabolism of naturally occurring propenylbenzene derivatives. III. Allylbenzene, propenyl benzene, and related metabolic products.

The acidic and neutral urinary metabolites of allylbenzene, propenylbenzene, 1'-hydroxyallylbenzene, and cynnamyl alcohol were identified and related through a common metabolic scheme. The rat metabolizes allylbenzene to 1'-hydroxyallylbenzene which can rearrange to yield cinnamyl alcohol whick is further metabolized. This mechanism is proposed to account for the appearance of "propenyl type" metabolites from allylbenzene compounds. Propenylbenzene is oxidized to cynnamyl alcohol. Both 1'-hydroxyallylbenzene and cunnamyl alcohol are excreted unchanged in the neutral extract when given to rats. Allylbenzene and 1'-hydroxyallylbenzene yield basic ninhydrin-positive metabolites. Allylbenzene is first oxidized on the benzylic carbon to form 1'-hydroxyallylbenzene, which is further oxidized to form phenyl vinyl ketone, which condenses with the secondary amines piperidine and dimethylamine to form tertiary aminopropiophenones (Mannich bases). Analogous compounds, cinnamyl alcohol and propenylbenzene, do not yield Mannich base metabolites. This proposed metabolic scheme is consistent with the chemical mechanism operative in the synthesis of Mannich base from allylbenzene via chromic acid oxidation followed by amine addition.

Animals↗

Covalent binding to DNA in vitro of 2',3'-oxides derived from allylbenzene analogs.

Epoxidation at the allylic side chain is a major metabolic pathway for allylbenzene and its naturally occurring analogs safrole, estragole, and eugenol. We demonstrate herein that the epoxide metabolites of allylbenzene, estragole, and safrole can form covalent adducts with DNA in vitro, binding primarily to guanine, but also to the other three DNA bases. Epoxide hydrolases can prevent the binding of allylbenzene 2',3'-oxide to DNA in vitro. Four distinct adducts were detected by analytical TLC after the reaction of 2'-deoxyguanosine with allylbenzene 2',3'-oxide. One unstable adduct was formed rapidly, but gradually disappeared, whereas the other three adducts were formed more slowly but persisted. The major persistent adduct, which was isolated by preparative chromatography, was examined by MS and NMR. The structure of this adduct is 3'-N1-deoxyguanosyl-(2'-hydroxypropylbenzene). In addition, a generally applicable paradigm for the identification of deoxyguanosine or guanosine adducts by 13C and 1H NMR spectroscopy is presented.

Animals↗

Immunochemical identification of hepatic protein adducts derived from estragole.

Hepatic protein adducts derived from the allylbenzene food flavor estragole, which is hepatocarcinogenic when given to rodents at high doses, have been identified using immunochemical approaches. Male Fischer 344 rats were given estragole orally and hepatic protein adducts were detected by immunoblotting, using antisera raised by immunizing rabbits with 4-methoxycinnamic acid-modified rabbit serum albumin. A major 155-kDa adduct was expressed in livers of animals that had been treated with estragole at 100, 300, or 500 mg/kg. Levels of expression of the adduct increased disproportionately with respect to dose, and other adducts (170, 100, 44, and 35 kDa) were detected also in the high-dose group. Rats given estragole for 5 days, at 300 mg/kg/day, expressed predominantly 155- and 44-kDa adducts. The 155-, 100-, 44-, and 35-kDa adducts were detected in greatest abundance in liver microsomal fractions, while the 170-kDa adduct was most abundant in the nuclear fraction. Interestingly, whereas the 170-, 155-, 100-, and 35-kDa adducts were detected in cytosolic fractions, relatively low levels of the 44-kDa adduct were detected in nuclear fractions but not in cytosolic fractions. The various adducts were solubilized when microsomal fractions were extracted with sodium carbonate and were digested by trypsin. This implies that the target proteins are peripheral membrane proteins bound to the outer surface of microsomal membranes. Experiments undertaken with isolated rat hepatocytes and with V79 cells transfected with human monoamine phenol sulfotransferase cDNA revealed that adduct formation required 1'-hydroxylation of estragole, followed by sulfation. The pattern of adducts expressed when the transfected V79 cells were incubated with 1'-hydroxyestragole was very similar to that expressed in livers of estragole-treated rats. These cells should constitute a valuable in vitro model system for investigation of toxicological consequences arising from estragole-induced protein adduct formation.

Allylbenzene Derivatives↗

Hydrolysis of the 2',3'-allylic epoxides of allylbenzene, estragole, eugenol, and safrole by both microsomal and cytosolic epoxide hydrolases.

2',3'-Allylic epoxide derivatives of allylbenzene and its analogs estragole, eugenol, and safrole were synthesized, and their enzymatic conversion to dihydrodiols by cytosolic and microsomal epoxide hydrolases was examined. All four epoxides were good substrates for both epoxide hydrolases, with Michaelis constants in the low micromolar range. Two putatively selective inhibitors of cytosolic and microsomal epoxide hydrolases, trichloropropylene oxide and nordihydroguaiaretic acid, were used to inhibit the hydrolysis of these allylic epoxides. Minimal selectivity toward either hydrolase was seen with either inhibitor, suggesting that the "selectivity" of these inhibitors is highly substrate-dependent. The susceptibilities of these epoxides to rapid hydrolysis by both epoxide hydrolases may explain their low genotoxic potencies in vivo.

Allylbenzene Derivatives↗

Detoxication of the 2',3'-epoxide metabolites of allylbenzene and estragole. Conjugation with glutathione.

The enzymatic detoxication in vitro of the 2',3'-epoxide derivatives of allylbenzene and estragole was examined, and the relative rates of enzymatic glutathione conjugation and epoxide hydrolysis were compared with those for styrene 1',2'-oxide. HPLC was used to determine the amounts of dihydrodiol and glutathione conjugate metabolites formed by cell extracts from several sources. Although some differences among species were observed, in general, the rates of epoxide inactivation by both pathways are similar. We conclude that one explanation for the apparent lack of genotoxicity of these allylic epoxides in vivo may be their rapid metabolic inactivation by both glutathione S-transferases and epoxide hydrolases, which occur to approximately equal degrees in vitro.

Allylbenzene Derivatives↗

Investigation of the role of the 2',3'-epoxidation pathway in the bioactivation and genotoxicity of dietary allylbenzene analogs.

The genotoxic potential of naturally occurring allylbenzene analogs, including safrole, eugenol, estragole, and others, has been examined in many studies over the past 30 years. It has been established that these compounds are subject to biotransformation in the liver, which can lead to the formation of reactive electrophilic intermediates. The major route of bioactivation is via hydroxylation of the 1' carbon atom of the allylic side chain. We have synthesized 2',3'- (allylic) epoxide derivatives of allylbenzene, estragole eugenol and safrole, and have used them to characterize the genotoxic potential of epoxidation at the allylic double bond for allylbenzene and its naturally occurring analogs. In order to assert that this pathway has the potential for genotoxicity, it is necessary to demonstrate (1) that epoxide metabolites of these compounds are capable of forming covalent adducts with DNA bases; and (2) that these epoxide metabolites are actually formed in vivo. We have demonstrated that allylic epoxides derived from allylbenzene and estragole are capable of forming covalent adducts with all four deoxyribonucleotides in vitro and, in the case of deoxyguanosine, form at least four different adducts. We also deduce, from evidence obtained using the isolated perfused rat liver, that formation of potentially genotoxic 2',3' epoxide metabolites occurs readily in vivo, but that these metabolites are rapidly further metabolized to less toxic dihydrodiol or glutathione conjugates. We conclude that 2',3' epoxide metabolites of allylbenzene analogs are formed in vivo and that these epoxides are sufficiently reactive to facilely form covalent bonds with DNA bases. Epoxide formation at the allylic double bond represents, therefore, a potentially genotoxic bioactivation pathway for allylbenzene analogs. However, comparison of the relative kinetics of epoxide metabolism and epoxide formation suggests that a wide margin of protection from DNA covalent adduct formation exists in the rat liver, thus preventing genotoxicity resulting from this pathway to any significant degree. In this regard, we have also observed that the general rate of epoxide hydrolysis is much greater in human liver than in rat liver. We therefore suggest that while the epoxidation pathway poses a potential genotoxic threat to humans, no actual genotoxicity occurs as a result of this metabolic pathway.

Animals↗

The side-chain epoxidation and hydroxylation of the hepatocarcinogens safrole and estragole and some related compounds by rat and mouse liver microsomes.

Safrole, estragole, and their 2',3'-oxides were hydroxylated by hepatic microsomes from rats and mice at the 1'-carbon; trans-anethole was hydroxylated at the 3'-carbon; and safrole, estragole, and their 1'-hydroxy derivatives were epoxidized at the 2',3'-double bond. The 2',3'-epoxidation of eugenol was just detectable. The formation of these metabolites was dependent on an NADPH-generating system and on cytochrome P-450. In the absence of 3,3,3-trichloropropylene oxide little or no safrole-, estragole-, or eugenol-2',3'-oxide was recovered when these oxides were added to the incubations; recoveries of 50-70% were obtained in its presence. The recoveries of the 2',3'-oxides of 1'-hydroxy-safrole and of 1'-hydroxyestragole were 50-80% in the absence of trichloropropylene oxide and nearly quantitative in its presence. All incubations for analysis of epoxidation rates contained trichloropropylene oxide. The rates of metabolite formation ranged from about 0.4 nmol of eugenol-2',3'-oxide/mg protein/h by female rat liver microsomes to about 270 nmol of trans-3'-hydroxyanethole/mg protein/h for male rat liver microsomes. The rates of epoxidation and hydroxylation were greater for the estragole derivatives than for the safrole derivatives. The rates of epoxidation of safrole and estragole were greater than for their 1'-hydroxy derivatives.

Allylbenzene Derivatives↗

Fumigant activity of (E)-anethole identified in Illicium verum fruit against Blattella germanica.

The insecticidal activities of materials derived from the fruit of star anise, Illicium verum, against adults of Blattella germanica were examined by direct contact application and fumigation methods, and compared with those of DDVP, deltamethrin and hydramethylnon. The biologically active constituent of the Illicium fruit was characterized as the phenylpropene, (E)-anethole, by spectroscopic analysis. In a filter paper diffusion test with females, (E)-anethole caused 80.3% mortality at 0.159 mg cm-2 at 1 and 3 days after treatment (DAT), whereas 16.7% mortality at 3 DAT was achieved at 0.079 mg cm-2. DDVP and deltamethrin gave > 90% mortality at 0.019 mg cm-2 at 1 DAT. At 0.009 mg cm-2, DDVP and deltamethrin showed 73.3 and 60% mortality at 1 DAT, respectively, but 93.3 and 76.7% mortality at 3 DAT. Hydramethylnon exhibited 0 and 93.3% mortality at 0.159 mg cm-2 at 1 and 3 DAT, respectively, whereas 6.7% mortality at 3 DAT was observed at 0.079 mg cm-2. In a fumigation test with females, (E)-anethole was much more effective in closed cups than in open ones, indicating that the insecticidal activity of the compound was largely attributable to fumigant action. (E)-Anethole and DDVP caused 100% mortality at 0.398 and 0.051 mg cm-2 4 and 1 h after treatment, respectively. (E)-Anethole showed 46.7% mortality at 0.199 mg cm-2 at 3 DAT, whereas deltamethrin and hydramethylnon at 0.796 mg cm-2 was ineffective for 3-day period. As naturally occurring insect-control agents, the I verum fruit-derived materials described could be useful for managing populations of B germanica.

Allylbenzene Derivatives↗

Contact and fumigant activities of constituents of Foeniculum vulgare fruit against three coleopteran stored-product insects.

The insecticidal activities of materials derived from the fruit of fennel, Foeniculum vulgare, against adults of Sitophilus oryzae, Callosobruchus chinensis and Lasioderma serricorne were examined using direct contact application and fumigation methods. The biologically active constituents of the Foeniculum fruits were characterized as the phenylpropenes (E)-anethole and estragole, and the monoterpene (+)-fenchone, by spectroscopic analysis. Responses varied with insect species, compound, dose and exposure time. In a filter paper diffusion test, estragole at 0.168 mg cm-2 caused 91% mortality to S oryzae adults within 1 day after treatment (DAT), whereas (+)-fenchone and (E)-anethole gave over 90% mortality at 2 and 4 DAT, respectively. Against C chinensis adults, all test compounds revealed potent insecticidal activities at 0.021 mg cm-2 at 2 DAT. Against L serricorne adults at 0.105 mg cm-2, (E)-anethole gave 100% mortality at 1 DAT, whereas 90 and 60% mortality at 4 DAT was achieved with estragole and (+)-fenchone, respectively. In a fumigation test, the compounds were much more effective against adults of S oryzae, C chinensis and L serricorne in closed cups than in open ones, indicating that the insecticidal activity of test compounds was largely attributable to fumigant action. As naturally occurring insect-control agents, the F vulgare fruit-derived materials described could be useful for managing field populations of S oryzae, C chinensis and L serricorne.

Allylbenzene Derivatives↗

Biotransformations of propenylbenzenes by an Arthrobacter sp. and its t-anethole blocked mutants.

Propenylbenzenes are often used as starting materials in the chemical synthesis of aroma compounds and fine chemicals. In the present study, we demonstrate the ability of an Arthrobacter sp. to transform various structures of propenylbenzenes derived from essential oils to flavor, fragrance, and fine chemicals. Arthrobacter strain TA13 and its t-anethole blocked mutants (incapable of growing on t-anethole) converted isoeugenol to vanillin and vanillic acid; and safrole to hydroxychavicol. High conversion efficiencies were achieved in the biotransformations of isosafrole to piperonylic acid, and eugenol to a mixture of ferulic acid and vanillic acid. In addition, anisic acid was produced in high yields from t-anethole, anisyl alcohol, or anisaldehyde. The accumulation of the corresponding aromatic acids from the tested propenylbenzenes is due to the lack of m-demethylase activity in strain TA13 that prevents further cleavage of the benzene ring. Interestingly, in the transformation of eugenol (a 2-propenylbenzene) the side chain was initially oxidized to the corresponding cinamic acid derivative (ferulic acid) while the 1-propenylbenzenes gave substituted benzoic acids, suggesting two different chain shortening mechanisms.

Allylbenzene Derivatives↗

Food protective effect of acaricidal components isolated from anise seeds against the stored food mite, Tyrophagus putrescentiae (Schrank).

The acaricidal activity of anise seed-isolated anisaldehyde and commercially available components of anise seed was examined against Tyrophagus putrescentiae adults and compared with those of synthetic acaricides, benzyl benzoate, dibutyl phthalate, and N,N-diethyl-m-toluamide (DEET). On the basis of LD50 (50% lethal dose) values, the compound most toxic to T. putrescentiae adults was anisaldehyde (LD50, 0.96 microg/cm2), followed by benzyl benzoate (LD50, 11.3 microg/cm2), anethole (LD50, 12.3 microg/cm2), dibutyl phthalate (LD50, 13.3 microg/cm2), DEET (LD50, 13.5 microg/cm2), estragole (LD50, 17.4 microg/cm2), and myrcene (LD50, 56.2 microg/cm2). Anisaldehyde was about 11.8 and 14 times more toxic than benzyl benzoate and DEET against T. putrescentiae adults, respectively. The results suggested that anisaldehyde, anethole, estragole, and myrcene derived from anise seeds are useful as a lead compound to development new agents for selective control of the stored food mite.

Allylbenzene Derivatives↗

Synthesis and antioxidant, anti-inflammatory and gastroprotector activities of anethole and related compounds.

Some derivatives of trans-anethole [1-methoxy-4-(1-propenyl)-benzene] (1) were synthesized, by introducing hydroxyl groups in the double bond of the propenyl moiety. Two types of reactions were performed: (i) oxymercuration/demercuration that formed two products, the mono-hydroxyl derivative, 1-hydroxy-1-(4-methoxyphenyl)-propane (2) and in lesser extent the dihydroxyl derivative, 1,2-dihydroxy-1-(4-methoxyphenyl)-propane (3) and (ii) epoxidation with m-chloroperbenzoic acid that also led to the formation of two products, the dihydroxyl derivative (3) and the correspondent m-chloro-benzoic acid mono-ester, 1-hydroxy-1(4-methoxyphenyl)-2-m-chlorobenzoyl-propane (4). The structures of these compounds were confirmed mainly by mass, IR, 1H and 13C NMR spectral data. The activity of anethole and hydroxylated derivatives was evaluated using antioxidant, anti-inflammatory and gastroprotector tests. Compounds (2) and (3) were more active antioxidant agents than (1) and (4). In the anti-inflammatory assay, anethole showed lower activity than hydroxylated derivatives. Anethole and in lesser extent its derivatives 2 and 4 showed significant gastroprotector activity. All tested compounds do not alter significantly the total number of white blood cells.

Allylbenzene Derivatives↗

Synthesis and hypolipidaemic evaluation of a series of alpha-asarone analogues related to clofibrate in mice.

A series of alpha-asarone analogues related to clofibrate, containing an acetic acid group at C-2 of the aromatic ring, has been prepared as the acids or as the ethyl and methyl esters. The corresponding alcohols were also synthesized by reduction of the ethyl esters. The compounds were examined in hyperlipidaemic male mice to evaluate their ability to modify serum lipoprotein cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides after oral administration of 40 and 80 mg kg(-1) for 6 days. Except for methyl 2-methoxy-5-nitro-4-(2-propenyl)phenoxyacetate at either dose, these clofibrate-related phenoxyacetic acid derivatives were found to have significant hypocholesterolaemic activity. Levels of low-density lipoprotein cholesterol and triglycerides were significantly reduced and those of high-density lipoprotein cholesterol were elevated. 2-Methoxy-5-nitro-4-(2-propenyl)phenoxyacetic acid was active at both doses in all the tests. Clofibrate (150 mg kg(-1)) was more potent at reducing low-density lipoprotein cholesterol. No activity was detected for the alcohol derivatives. These preliminary results suggest that this class of compound might have more promise as potential hypolipidaemic agents than other alpha-asarone derivatives. Further investigation and characterization should be performed to determine the mode of action of these agents on lipid metabolism.

Allylbenzene Derivatives↗