- Synthesis and antiplatelet activity of 2-(diethylamino)-7-ethoxychromone and related compounds
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2-(Diethylamino)-7-ethoxychromone 3a and its 2-(1-piperidinyl)analogue 3b were synthesized by reaction of 3-ethoxyphenol 1 with 3-(dialkylamino)-3-oxo-propanoic acid ethyl ester 2 in the presence of phosphorus oxychloride.With a view to improve their biological activity the above 7-ethoxychromones 3 were submitted to some structural modifications firstly involving the 4-CO group.The 4H-chromenes 4 and the 4-thiochromones 5 were obtained by action of suitable reagents.The compounds 5 were then easily transformed to 4-(methylthio)chromenylium iodides 6.Then from the 2-(diethylamino)-7-ethoxychromone 3a were obtained with suitable reactions the 3,6-diamino derivative 8, the 3- and 6-formyl derivatives 9a,b and the Mannich base 10.By action of acetic anhydride this latter compound yielded the methylenebis derivative 11.Most of the above compounds were tested in vitro for their inhibitory activities against human platelet aggregation induced by collagen, ADP and arachidonic acid.Among the tested compounds the 2-(diethylamino)-7-ethoxychromone 3a showed the highest activity.
- Mazzei, M.,Sottofattori, E.,Braccio, M. Di,Balbi, A.,Leoncini, G.,et al.
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- Hollow, mesoporous, eutectic Zn1?xMgxO nano-spheres as solid acid-base catalysts for the highly regio-selectiveO-methylation of 1,2-diphenols
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The highly regio-selectiveO-methylation of catechol with dimethyl carbonate (DMC), catalyzed by a solid acid-base catalyst, is an environmentally friendly chemical process for industrial production of guaiacol. However, a guaiacol yield below 84% and high reaction temperature above 280 °C limit its industrial application. Here, hollow, mesoporous Zn1?xMgxO nano-spheres with a eutectic structure, denoted as Zn1?xMgxO HMNSs (x= 0.012-0.089), are facilely fabricatedviathe calcination of Mg2+/Zn2+ion-adsorbing carbon spheres at 500 °C in air. In theO-methylation of catechol with DMC at 180 °C, Zn1?xMgxO HMNSs (x= 0.052) afford guaiacol in 95.5% yield with a complete catechol conversion. Furthermore, 89.0-95.3% mono-ether yields with high 1,2-diphenol conversions (94.5-100%) are also obtained for the other 1,2-diphenols bearing -CH3and -Br groups. Moreover, a plausible mechanism for highly selectiveO-methylation of catechol with DMC is proposed, in which the single-site activation and double-site activation of phenolic hydroxyls by the basic oxygen of Mg-O afford guaiacol and veratrole, respectively.
- Liu, Jie,Ma, Xuebing,Wang, Xuri,Xie, Guangxin,Yin, Zuyong,Zhang, Jianing
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p. 7454 - 7466
(2021/11/23)
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- Phthalocyanine-based discotic liquid crystals switching from a molten alkyl chain type to a flying-seed-like type
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We have synthesised a series of phthalocyanine-based discotic liquid crystals, (m-CnOPhO)8PcCu (n = 1-20: 2a-o), and investigated their mesomorphism by using a polarizing optical microscope (POM), a differential scanning calorimeter (DSC) and a temperature-dependent small angle X-ray diffractometer. We found that each of the derivatives 2a-o shows mesomorphism. However, the mesomorphism of the (m-CnOPhO)8PcCu derivatives strongly depends on the alkoxy chain length (n). The mesomorphism of the short chain-substituted derivatives 2a-e for n = 1-5 is a flying-seed-like type induced by flip-flop of the peripheral bulky substituents, whereas the mesomorphism of the long chain-substituted derivatives 2j-o for n = 10-20 is a conventional molten alkyl chain type induced by melting of the long alkyl chains. The moderately long chain derivatives (2f-i) for n = 6-9 in between show both types of mesophases. The detailed temperature-dependent X-ray diffraction measurements were carried out for three representative derivatives, 2b (n = 2 for n = 1-5), 2h (n = 8 for n = 6-9), and 2o (n = 20 for n = 10-20). As a result, we revealed that the Colro(P2m) mesophase in 2b (n = 2) gave a halo denoted as Haloarom. at d ? 5.2 ? due to flip-flop of the bulky aromatic substituents, and that the Colho mesophase in 2o (n = 20) gave a halo denoted as Haloalkyl at d ? 4.6-4.8 ? due to melting of the long alkyl chains. Therefore, we can distinguish the type of mesophase from Haloarom. and Haloalkyl. Very interestingly, the (m-C8OPhO)8PcCu (2h) derivative having moderately long alkyl chains gave Haloalkyl at about 4.8 ? in the lower temperature mesophase of Colho, but Haloarom. at about 5.2 ? in the higher temperature mesophase of Colro(P21/a). This means that melting of the alkyl chains induces the Colho phase in the lower temperature region, but that flip-flop of the bulky aromatic substituents induces the Colro(P21/a) phase in the higher temperature region. This unusual reverse phase transition sequence from a higher symmetry of the Colh mesophase to a lower symmetry of the Colr mesophase on a heating stage is attributable to such a unique stepwise melting of these two different types of substituents. To the best of our knowledge, this mesogen (2h) is the first example switching mesomorphism from the molten alkyl chain type to the flying-seed-like type in a discotic liquid crystal.
- Nakamura, Hiromu,Sugiyama, Kouki,Ohta, Kazuchika,Yasutake, Mikio
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p. 7297 - 7306
(2017/08/03)
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- Virtual screening and optimization yield low-nanomolar inhibitors of the tautomerase activity of Plasmodium falciparum macrophage migration inhibitory factor
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The Plasmodium falciparum orthologue of the human cytokine, macrophage migratory inhibitory factor (PfMIF), is produced by the parasite during malaria infection and modulates the host's immune response. As for other MIF orthologues, PfMIF has tautomerase activity, whose inhibition may influence the cytokine activity. To identify small-molecule inhibitors of the tautomerase activity of PfMIF, virtual screening has been performed by docking 2.1 million compounds into the enzymatic site. Assaying of 17 compounds identified four as active. Substructure search for the most potent of these compounds, a 4-phenoxypyridine analogue, identified four additional compounds that were purchased and also shown to be active. Thirty-one additional analogues were then designed, synthesized, and assayed. Three were found to be potent PfMIF tautomerase inhibitors with Ki of ～40 nM; they are also highly selective with Ki > 100 μM for human MIF.
- Dahlgren, Markus K.,Garcia, Alvaro Baeza,Hare, Alissa A.,Tirado-Rives, Julian,Leng, Lin,Bucala, Richard,Jorgensen, William L.
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supporting information
p. 10148 - 10159
(2013/01/16)
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- METHODS AND COMPOSITIONS FOR CONTROL OF GYPSY MOTHS, Lymanria dispar
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The invention provides in part dialkoxybenzene and eugenol compounds for controlling infestation by a Lymantria dispar, and methods thereof. The compounds include a compound of Formula I: where R1 may be methyl, ethyl, propyl, n-butyl, isopentyl (3-methylbutyl) or allyl; R2 may be at positions 2, 3 or 4 and may be H, methyl, ethyl, propyl, n-butyl, isopentyl (3-methylbutyl) or allyl; and R3 may be optionally present at positions 2, 3 and 4, and is allyl; with the provisos that when R2 is at position 2, R3 if present is at position 3, or when R2 is at to position 3, R3 if present is at positions 2 or 4, or when R2 is at position 4, R3 if present is at position 2; or of Formula II: where R1 may be methyl, ethyl, propyl, n-butyl, isopentyl (3-methylbutyl) or allyl; or mixtures thereof.
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Page/Page column 20
(2010/08/07)
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- METHODS AND COMPOSITIONS FOR CONTROL OF CABBAGE LOOPER, Trichoplusia ni
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The invention provides in part dialkoxybenzene compounds for controlling infestation by a Trichoplusia ni, and methods thereof. The compounds include a compound of Formula I: where R1 may be methyl, ethyl, propyl, n-butyl, isopentyl(3-methylbutyl) or allyl; R2 may be at positions 2, 3 or 4 and may be H, methyl, ethyl, propyl, n-butyl, isopentyl(3-methylbutyl) or allyl; and R3 may be optionally present at positions 2, 3 and 4, and is allyl; except that when R2 is at position 2, R3 if present is at position 3, and when R2 is at position 3, R3 if present is at positions 2 or 4, and when R2 is at position 4, R3 if present is at position 2, and when R2 is at position 4 and R3, if present, has reacted with an OH group at position 1 in a Markovnikov sense, then R3 becomes R4, a dihydrofuran.
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Page/Page column 10
(2010/07/04)
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- Dialkoxybenzene and dialkoxyallylbenzene feeding and oviposition deterrents against the cabbage looper, trichoplusia ni: Potential insect behavior control agents
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The antifeedant, oviposition deterrent, and toxic effects of individual dialkoxybenzene compounds/sets and of hydroxy- or alkoxy-substituted allylbenzenes, obtained through Claisen rearrangement of substituted allyloxybenzenes, were assessed against the cabbage looper, Trichoplusia ni, in laboratory bioassays. Most of the compounds/sets strongly deterred larval feeding, with some exhibiting mild toxic and oviposition deterrent effects as well. Some of the compounds/sets were more active than the commercial insect repellent, DEET (N,N-diethyl-m-toluamide), as both feeding and oviposition deterrents against the cabbage looper. On the basis of the obtained oviposition data a general hypothesis was proposed regarding the oviposition sites: one binding mode with the alkyl and allyl groups on the same side of the benzene ring resulted in deterrence, the other with alkyl and allyl groups on opposite sides of the benzene ring resulted in stimulation. The results suggest some structure-activity relationships useful in improving the efficacy of the compounds and designing new, nontoxic insect control agents for agriculture.
- Akhtar, Yasmin,Yu, Yang,Isman, Murray B.,Plettner, Erika
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scheme or table
p. 4983 - 4991
(2011/08/06)
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- Screening of dialkoxybenzenes and disubstituted cyclopentene derivatives against the cabbage looper, Trichoplusia ni, for the discovery of new feeding and oviposition deterrents
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The antifeedant, oviposition deterrent, and toxic effects of dialkoxybenzene minilibraries and of disubstituted cyclopentene minilibraries (i.e., consisting of four to five compounds) along with their pure constituent compounds were assessed against third instar larvae and adults of the cabbage looper, Trichoplusia ni, in laboratory bioassays in a search for new insect control agents. These compounds mimic naturally occurring bioactive odorants and tastants and are relatively easily prepared from commodity chemicals. Most of these libraries strongly deterred larval feeding, with some exhibiting strong toxic and oviposition deterrent effects as well. Our results suggest some structure-function relationships within these libraries. Replacement of a methyl group with larger alkyl substituents increased the feeding deterrent effects in most cases. The presence of a free hydroxyl group, irrespective of the carbon framework or alkyl substituent, served to reduce feeding deterrent effects in all series of compounds. Further, exceeding a certain group size also generally had a detrimental effect. This information will be useful in designing new insect control agents for agriculture. Some of these libraries and compounds may have potential for development as commercial insecticides.
- Akhtar, Yasmin,Isman, Murray B.,Paduraru, Peggy M.,Nagabandi, Srinivas,Nair, Ranjeet,Plettner, Erika
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scheme or table
p. 10323 - 10330
(2009/10/02)
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- Monooxygenation of aromatic compounds by dioxygen with bioinspired systems using non-heme iron catalysts and tetrahydropterins: Comparison with other reducing agents and interesting regioselectivity favouring meta-hydroxylation
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Monooxygenation of aromatic compounds by dioxygen in the presence of catalytic amounts of an iron(II) salt and tetrahydropterins as reducing agents occurs with a regioselectivity favouring meta-hydroxylation of arenes bearing an electron-donating substituent, such as anisole, phenetole, toluene, and ethylbenzene. Comparison of similar systems using various reducing agents showed that only tetrahydropterins and ascorbate led to such a major meta-hydroxylation. The tetrahydropterin- and ascorbate-dependent systems should be useful for the preparation of meta-hydroxylated metabolites of aromatic drugs, as shown here in the case of diclofenac.
- Mathieu, Delphine,Bartoli, Jean Fran?ois,Battioni, Pierrette,Mansuy, Daniel
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p. 3855 - 3862
(2007/10/03)
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- Process for functionalising a phenolic compound carrying an electron-donating group
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The invention concerns a method for functionalizing a phenolic compound bearing an electron-donor group, in said group para position, inter alia a method for the amidoalkylation of a phenolic compound bearing an electron-donor group, and more particularly, a phenolic compound bearing an electron-donor group preferably, in the hydroxyl group ortho position. The method for functionalizing in para position with respect to an electron-donor group carried by a phenolic compound is characterised in that the phenolic compound bearing an electron-donor group is subjected to the following steps: a first step which consists of protecting the hydroxyl group in the form of a sulphonic ester function; a second step which consists in reacting the protected phenolic compound with an electrophilic reagent; optionally, a third step deprotecting the hydroxyl group.
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- Novel synthesis of monoethers of hydroquinone and resorcinol on soluble polymer-supports
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Monoethers of hydroquinone and resorcinol were easily prepared using PEG as soluble polymer-supports, monoprotection group and phase transfer catalyst with good yields and high selectivity of functionlization in homogenous solution.
- Yang, Guichun,Chen, Zuxing,Zhang, Zhaojun,Qiu, Xiaoling
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p. 3637 - 3642
(2007/10/03)
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- O-alkylation of phenolic compounds via rare earth orthophosphate catalysts
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Carbocyclic/aliphatic ethers, for example anisole, quaicol, guaethol, p-methoxyphenol and ethylene dioxybenzene, are selectively prepared, in good yield, by reacting a phenolic compound, for example a phenol, hydroquinone, pyrocatechin, naphthol, or the like, with an alcohol, for example methanol, ethanol, isopropanol, ethylene glycol, etc., in gaseous phase, in the presence of a catalytically effective amount of a trivalent rare earth metal orthophosphate, for example a lanthanum, cerium or samarium orthophosphate, optionally doped with an alkali or alkaline earth metal, preferably cesium.
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- Acid-catalysed Aromatisation of Benzene cis-1,2-dihydrodiols: a Carbocation Transition State poorly stabilised by Resonance
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Acid-catalysed dehydration of 3-substituted benzene cis-1,2-dihydrodiols exhibits a Hammett plot with ρ=-8.2, consistent with reaction via a benzenonium ion-like intermediate; however, correlation of +M resonance substituents such as Me and MeO by ?p rather than ?+ constants indicates a marked imbalance between resonance and inductive stabilisation of the transition state.
- Boyd, Derek R.,Blacker, John,Byrne, Briege,Dalton, Howard,Hand, Mark V.,et al.
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p. 313 - 314
(2007/10/02)
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- 16-Substituted polyunsaturated hexadecanoic fatty acids
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Sixteen carbon atom carboxylic acids having 16-phenoxy or 16-phenylthio substituents, and 0, 1, or 4 triple bonds, methods of preparing them, and pharmaceutical preparations containing them. These compounds are useful as lipoxygenase inhibitors.
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