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Pyrazoles 3-hydroxy- from

Pyrazole ring from azo compounds 5-Hydroxy-6(2H)-cyclobepta[c]pyrazolones... [Pg.423]

Schroter HB, Neumann D, Katritzky AR, Swinboume FJ (1966) Withasomnine. A pyrazole alkaloid from Withania somnifera Dun. Tetrahedron 22 2895-2897 Schulte KE, Rucker G, El-Kersch M (1972) Nicotin und 3-Formyl-4-hydroxy-2H-pyran aus... [Pg.208]

Cyclopent-2-en-l-one, 2-hydroxy-3-methyl-synthesis, 3, 693 Cyclopentenone, 4-methoxy-formation, 1, 423 Cyclopenthiazide as diuretic, 1, 174 Cyclopent[2,3-d]isoxazol-4-one structure, 6, 975 Cyclophane conformation, 2, 115 photoelectron spectroscopy, 2, 140 [2,2]Cyclophane conformation, 2, 115 Cyclophanes nomenclature, 1, 27 Cyclophosphamide as pharmaceutical, 1, 157 reviews, 1, 496 Cyclopiloselloidin synthesis, 3, 743 Cyclopolymerization heterocycle-forming, 1, 292-293 6H-Cyclopropa[5a,6a]pyrazolo[l,5-a]pyrimidine pyrazoles from, 5, 285 Cydopropabenzopyran synthesis, 3, 700 Cyclopropachromenes synthesis, 3, 671 Cyclopropa[c]dnnolines synthesis, 7, 597 Cyclopropanation by carbenes... [Pg.591]

Recently, the pyrazole group containing bisphenols have been synthesized from activated aromatic dihalides and 3,5-bis (4-hydroxy phenyl)-4-phenyl pyrazole or 3,5-bis(4-hydroxy phenyl)-1,4-diphenyl pyrazole. A novel synthesis of imido aryl containing bisphenols has been reported [32]. N-substituted l,4-bis(4-hydroxy phenyl)-2,3-naphthalimides were prepared from phenolphthalein and copolymerized with aromatic sulfone or ketone difluorides to obtain the poly(imidoaryl ether) sulfones/ ketones. [Pg.37]

It is known that certain coumarins are transformed into 5-(2-hydroxy-phenyl)-3H-pyrazol-3-ones by reaction with hydrazines [10]. Upon appUca-tion of this method, the expected pyrazolones 25 were synthesized starting from 3-nitrocoumarins [11] as known in (Scheme 6). [Pg.130]

The nitrosation of oximes can also serve to produce N-hydroxy-N-nitrosamines (Scheme 3.9). The acidified nitrite procedure can be applied to oximes derived from terpenes [132] and hydroxyguanidine [133] for the synthesis of N-hydroxy-N-nitrosamines. However, some a, 5-uri saturated oximes were converted into pyrazole-1,2-dioxides [134]. The alkyl nitrites under basic conditions have produced interesting results. Quinone dioximes yielded only monodiazeniumdiolates [135], while simple aliphatic oximes gave products resulting from addition to the imine double bond... [Pg.67]

Like D-glucose and D-fructose, however, D-xylose can be utilized chemic ly or microbially—to generate a variety of interesting five-ca n c emica s o er than furfural (vide supra) or xylitol, a noncaloric sweetener, both being duectly produced from xylan hydrolysates, that is, without the actual isolation of the sugar. Other readily accessible intermediate products of high preparative utiUty (Scheme 2.14) are the open-chain fixed dithioacetal, the D-xylal, and D-hydroxy-xylal esters, or pyrazol or imidazol A -heterocycles with a hydrophilic trihydroxypropyl side chain. [Pg.46]

Pyrazoles were obtained from corresponding 2-hydroxy(or aIkoxy-)imino-1,3-diketones or related ketoesters and hydrazine . Thus, reaction of oximes 112 with hydrazine in ethanol afforded aminopyrazoles 113 in 48-95% yields (equation 48) . Interaction of... [Pg.249]

The checkers noted (by NMR) a second minor component in the crude solid. They suggest recrystallization of the crude solid from warm hexanes. The submitters noted both components and identified them (by NMR) as the anti and syn isomers of the hydroxy group. Both isomers are converted to the pyrazole upon treatment with hydrazine hydrate. [Pg.56]

However, chromones react differently, because the phenolic hydroxy group in the ring-opened intermediate is unreactive. Thus, isoxazoles (264) result from the reaction with hydroxylamine, and a pyrazole is formed with hydrazine. y-Pyrones also give pyrazoles with hydrazine. [Pg.207]

Tartrazine was separated by ion-pair HPLC from its subsidiary dye 3-carboxy-5-hydroxy-1 -p-sulfopheny-4-phenylazo-pyrazole disodium salt (195) and from its intermediates sulfanilic acid and l-(4-sulfophenyl)-3-carboxy-5-hydroxypyrazolone (pyrazolone-T) by means of TBA hydroxide (194,212). Ion-pair chromatography was also used for the determination of free and bound nonsulfonated aromatic amines in tartrazine after reduction with dithionite, diazotization with sodium nitrite, and coupling with R-salt (202). [Pg.559]

The aromatic 2-substituted pyrazole 1-oxides 74 are derived from pyrazoles 89 by appending an oxygen atom to the pyridine type ring nitrogen atom of the pyrazole nucleus. The second nitrogen atom of the pyrazole ring can be attached to an alkyl, aryl, hydroxy, or amino group. [Pg.13]

The 17a,20,20,21-bis(methylenedioxy)-lip-hydroxy-2-hydroxymethylene-6,16a-dimethyl-4,6-pregnadiene-3-one (1.19 g) is dissolved in 25 cc of ethanol. 300 mg of phenyl hydrazine is added and the mixture is refluxed under nitrogen for one hour. About 25 cc of water is added. The product is then extracted into 150 cc of ether. The extracts are washed with 2N HCI, with saturated sodium bicarbonate, water and saturated sodium chloride solution, and then dried over sodium sulfate and evaporated to dryness to give about 1.2 g of crude product. On crystallization from ether there is obtained as a major component the 17a,20,20,21-bis(methylenedioxy)-llfS-hydroxy-6,16a-dimethyl-2 -phenyl-4,6-pregnadieno-[3,2-c] pyrazole. [Pg.1135]


See other pages where Pyrazoles 3-hydroxy- from is mentioned: [Pg.190]    [Pg.10]    [Pg.75]    [Pg.89]    [Pg.316]    [Pg.316]    [Pg.36]    [Pg.215]    [Pg.770]    [Pg.205]    [Pg.88]    [Pg.92]    [Pg.105]    [Pg.118]    [Pg.136]    [Pg.183]    [Pg.392]    [Pg.133]    [Pg.134]    [Pg.214]    [Pg.216]    [Pg.294]    [Pg.167]    [Pg.174]    [Pg.693]    [Pg.202]    [Pg.51]    [Pg.23]    [Pg.162]    [Pg.57]    [Pg.135]    [Pg.138]    [Pg.228]    [Pg.231]    [Pg.516]    [Pg.770]   


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Pyrazole hydroxy

Pyrazoles 3- hydroxy

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