- A novel pathway in the photooxygenation of cyclic allenes
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(Matrix Presented) The photooxidation of cyclic allenes gives rise to cyclic 1,2,3-trione hydrates. The formation of these compounds points to a novel photooxidation mechanism involving both singlet and triplet oxygen. Upon placement of a methyl group on the allene, the mechanism shifts to predominantly an ene reaction. The corresponding cycloadditions with 4-methyl-1,3,4-triazoline-3,5-dione (MTAD) with cyclic allenes involve 2 equiv of MTAD. The dipolar intermediates are trapped with H2O to give α-urazole-substituted 2-cycloalkenones.
- Erden, Ihsan,Song, Jiangao,Cao, Weiguo
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- Development of a Scalable and Sublimation-Free Route to MTAD
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The cyclic azodicarbonyl 4-methyl-1,2,4-triazoline-3,5-dione (MTAD) is a versatile and powerful reagent used mainly in cycloaddition chemistry. Though known for more than 50 years, its unsafe preparation, as well as purification by sublimation, hampered i
- Siddiqi, Zohaib R.,Ungarean, Chad N.,Bingham, Tanner W.,Sarlah, David
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p. 2953 - 2959
(2020/12/21)
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- Intermediacy of a Persistent Urazole Radical and an Electrophilic Diazenium Species in the Acid-Catalyzed Reaction of MeTAD with Anisole
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The reaction of N-methyl-1,2,4-triazoline-3,5-dione (MeTAD) with anisole in the presence of trifluoroacetic acid affords unexpected disubstituted urazole products instead of the expected monosubstituted urazole as typically observed in the reactions of MeTAD with other substituted benzenes. Our investigation into the mechanism of formation of these disubstituted products suggests that MeTAD is capable of further reaction with the initially formed monosubstituted urazole to afford a persistent urazole radical. The identity of this radical has been established by UV-vis spectroscopy, the nature of its self-dimerization reaction, and via independent generation. Electrochemical oxidation of this radical was carried out, and the resulting diazenium ion was demonstrated to be reactive with added substituted benzenes, including anisole. When oxidation was carried out chemically using thianthrenium perchlorate in the presence of anisole it was shown to produce the same disubstituted products (and in the same ratio) as observed in the acid-catalyzed reaction. A common diazenium species is proposed to be active in both cases. We also report the synthesis and characterization of three interesting tetrazane dimers resulting from unstable urazole radicals.
- Breton, Gary W.,Suroviec, Alice H.
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p. 206 - 214
(2016/01/15)
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- Alternative synthetic routes to N-methyl-1,2,4-triazoline-3,5-dione (MeTAD) and other triazolinedione derivatives
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N-Methyl-1,2,4-triazoline-3,5-dione (MeTAD) is a powerful electrophile and a versatile synthetic reagent. In this Letter we describe two methods for the synthesis of N-methylurazole, the direct precursor to MeTAD, on gram scales and in good yields. Both methods provide pure urazole while avoiding the necessity of large scale purification via column chromatography or recrystallization. One of the methods proved to be amenable for the synthesis of derivatives other than N-methyl.
- Breton, Gary W.,Turlington, Mark
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supporting information
p. 4661 - 4663
(2015/02/19)
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- PROCESS FOR STRAIGHTENING KERATIN FIBRES WITH A HEATING MEANS AND DENATURING AGENTS
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The invention relates to a process for straightening keratin fibres, comprising: (i) a step in which a straightening composition containing at least two denaturing agents is applied to the keratin fibres, (ii) a step in which the temperature of the keratin fibres is raised, using a heating means, to a temperature of between 110 and 250° C.
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- Method for control of hyperlipidemia
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The present invention is directed to a method of controlling hyperlipidemia in mammals which comprises administering to a mammal an amount effective to control hyperlipidemia of a compound having hypolipidemic activity and the structural formula: STR1 wherein R1 is hydrogen, a C1 to C18 alkyl or substituted alkyl, a C2 to C18 alkenyl or substituted alkenyl, a C2 to C18 alkynyl or substituted alkynyl, a C4 to C10 cycloalkyl or substituted cycloalkyl, a C4 to C10 cycloalkenyl or substituted cycloalkenyl, phenyl, a substituted phenyl, cyano, phenalkyl, --CO--R9 or --Y--CO--R9 ; R2 is STR2 R3 and R4 can be the same or different and are each the same as R1 ; R5, R6 and R7 can be the same or different and are each hydrogen, a C1 to C18 alkyl or substituted alkyl, a C2 to C18 alkenyl or substituted alkenyl, a C1 to C18 alkynyl or substituted alkynyl, a C4 to C10 cycloalkyl or substituted cycloalkyl, a C4 to C10 cycloalkenyl or substituted cycloalkenyl, phenyl or substituted phenyl, phenalkyl, --CO--R9, or --Y--CO--R9, with the proviso that R5 and R6 together cannot be so bulky as to cause the compound to decompose; R8 is hydrogen, a C1 to C5 alkyl, a C4 to C10 cycloalkyl, --CO--R9 or Y--CO--R9 ; R9 is hydrogen, a C1 to C5 alkyl or substituted alkyl, a C2 to C5 alkenyl or substituted alkenyl, a C2 to C5 alkynyl or substituted alkynyl, phenyl or substituted phenyl, phenoxy or substituted phenoxy, a C1 to C5 alkoxy or substituted alkoxy, a C4 to C10 cycloalkyl or substituted cycloalkyl, a C4 to C10 cycloalkenyl or substituted cycloalkenyl, --NHC6 C5l , --NR10 R11 wherein R10 and R11 can be the same or different and are each hydrogen, a C1 to C5 alkyl or substituted alkyl, phenyl or substituted phenyl; Y is a C1 to C10 alkylene or substituted alkylene; R12 is --CO, --COH, --CS, --CSH, or a C1 to C4 alkylene group; and and the pharmaceutically acceptable salts, and mixtures thereof.
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- SINGLET OXYGEN AND TRIAZOLINEDIONE ADDITION TO AZINES
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Photooxygenation of azines, i.e., adamantanone azine (1) and benzonorborn-7-one azine (4), afforded in addition to the corresponding ketones, lactones derived from a carbonyl oxide intermediate via an electron transfer pathway.On the other hand, 4-substitued-1,2,4-triazoline-3,5-diones (TAD) react with azine 1 to give a 1,3-dipole, an azomethinimine intermediate as nitrogen analogue of a carbonyl oxide, which afforded the -cycloadducts in treatment with dipolarophiles.The mechanistic implications are discussed.
- Sato, Rikiya,Sonobe, Hideki,Akasaka, Takeshi,Ando, Wataru
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p. 5273 - 5280
(2007/10/02)
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- NEW FORMATION OF A 1,3-DIPOLE IN THE REACTION OF ADAMANTANONE AZINE WITH TRIAZOLINEDIONES: IN CONNECTION WITH REACTIVITY TOWARD SINGLET OXIGEN
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Tricyclo(3.3.1.1)decanone azine(adamantanone azine)reacts with 4-substituted 1,2,4-triazoline-3,5-diones under elimination of diazo adamantane to give a 1,3 dipole("azomethinimine"), which on treatment with dipolarophiles affords the (2+3)-cycloadducts.The reaction is compared with singlet oxygen oxidation.
- Akasaka, Takeshi,Sonobe, Hideki,Sato, Rikiya,Ando, Wataru
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p. 4757 - 4760
(2007/10/02)
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- Process for the production of 1,2,4-triazolidine-3,5-diones monosubstituted in the 4-position
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A process for the production of 1,2,4-triazolidine-3,5-diones corresponding to the general formula I STR1 in which R1 represents a monofunctional, optionally substituted hydrocarbon radical, optionally interrupted by hetero atoms or hetero atomic groups, characterized in that hydrazodicarbonamide or 1,2,4-triazolidine-3,5-dione is reacted with a primary amine corresponding to the general formula II or a monofunctional hydrazodiacarbonamide corresponding to the formula III in which R1 is as defined for formula I, at a temperature in the range from 150° to 280° C., under pressure of from 50 mbars to 5 bars, the reaction being accompanied by the elimination of ammonia.
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- Glycidyl-1,2,4-triazolidine-3,5-diones
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Glycidyl-1,2,4-triazolidine-3,5-diones corresponding to the general formula I STR1 wherein R1 represents a mono- to pentavalent substituted or unsubstituted straight-chain or branched-chain C1 -C3 O aliphatic group, a mono
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- Urazole analogs of prostaglandins
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Compounds of formula (I) STR1 wherein: n is 1 to 5 Y is --CH2 --CH2 or --CH=CH--; R1 is hydrogen or CO2 R1 represents an ester group in which the R1 moiety contains from 1-12 carbon atoms; R2 is hydrogen, C1-4 alkyl, or phenyl; R3 is hydroxy or protected hydroxy; R4 is hydrogen, C1-9 alkyl, C3-8 cycloalkyl, C3-8 cycloalkyl-C1-6 alkyl, phenyl, phenyl --C1-6 alkyl, naphthyl, naphthyl C1-6 alkyl, any of which phenyl moieties or naphthyl moieties may be substituted by one or more halogen, trifluoromethyl, C1-6 alkyl, hydroxy, C1-6 alkoxy, phenyl C1-6 alkoxy or nitro groups; R5 is hydrogen, C1-6 alkyl, C5-8 cycloalkyl, phenyl, phenyl-C1-6 alkyl or phenyl C3-6 cycloalkyl, any of which phenyl moieties may be substituted by one or more halogen, trifluoromethyl, C1-6 alkyl, C1-6 alkoxy or nitro groups; or R2 and R4 taken with the carbon atom to which they are joined represent a C5-8 cycloalkyl group; and salts thereof are useful for their prostaglandin-like activity.
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- Hydroxyalkyl-1,2,4-triazolidine-3,5-diones and a process for their production
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New hydroxyalkyl-1,2,4-triazolidine-3,5-diones corresponding to the general Formula I STR1 in which R1 represents a monofunctional to pentafunctional organic radical, optionally substituted and/or optionally interrupted by hetero atoms or hetero atom groups, R2, R3, R4 and R5 are the same or different and represent hydrogen, an aliphatic C1 -C1 O-radical, a cycloaliphatic C4 -C8 radical or an araliphatic C7 -C17 -radical, said radicals are optionally substituted by halogen, an aromatic C6 -C16 -radical or an aromatic C6 -C16 -radical substituted by halogen, C1 -C4 -alkyl or C1 -C4 -alkoxy, a and b are the same or different and represent a number of from 1 to 30, and n=a number of from 1 to 5. The new compounds are obtained by oxalkylation reaction using 1,2,4-triazolidine-3,5-diones of Formula I as starting materials in which a and b represent the number 0.
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