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Sulfone schiff bases

PSBA (CI-608), Other Sulfone Schiff Bases, and Biopolymers... [Pg.198]

Table 7 Comparative antimalarial, antileprotic, and metabolic data on other sulfone Schiff bases and biopolymers [42, 125, 132-135]... [Pg.202]

The 8-hydroxy-7-aminoquinoline-5-sulfonic acid was used to clarify the role of intramolecular hydrogen bonding on the cyclization rate of hydroxy Schiff bases in the preparation of 2-aryloxazolo[4,5-/i]quinoline-5-sulfonic acids 13. Irradiation... [Pg.197]

Thermal isomerization of certain cis-l,3,4-trisubstituted azetidin-2-ones 76 provided the trans isomer in good yield . Bases caused the isomerization of cis-3-substituted-4-formylazetidin-2-ones and of sulfonic acid derivatives of 3-aminoazetidin-2-ones during the formation of a Schiff base <00T3985>. 4-Acyloxy-iV-o-azidobenzoyl-P-lactams underwent ring expansion to produce l,3-oxazin-6-ones 77 . [Pg.79]

Both diazomethane and diazoethane add to these Schiff bases to give the 1,5- and 1,4,5-substituted triazolines, respectively (Scheme 92).347 348 A nitro group in the para position on the diphenyl sulfone ring assists addition, but has no effect on the sulfide compounds. Also, few... [Pg.281]

The authors reported the chiral separation of proline and thereonine amino acid up to 20 and 6g, respectively, in a single run. Micropreparative resolution of lecucine was presented. The resolution was discussed with respect to the degree of sorbent saturation with copper(II), elution rate, eluent concentration, temperature, and column loading condition [16]. Weinstein [74] reported the micropreparative separation of alkylated amino acids on a Chiral ProCu column. In another article, a preparative chiral resolution of 3-methylene-7-benzylidene-bicyclo[3.3.1]nonane was achieved on 7.5% silver(I)-d-camphor- 10-sulfonate CSP [75]. Later, Shieh et al. [71] used L-proline-loaded silica gel for the chiral resolution of (ft,5 )-phcnylcthanolaminc as the Schiff base of 2-hydroxy-4-methoxyacetophenone. Gris et al. [76] presented the preparative separations of amino acids on Chirosolve L-proline and Chirosolve L-pipecolic acid CSPs. [Pg.271]

Schiff base and related complexes of uranium and thorium are widely described in recent literature and covered in a review [463]. Those of U(VI) have a practical use as catalytic organic oxidants [460] or as part of a polystyrene-supported chelating resin [464,465]. Among other Schiff base precursors, salicylaldehyde [466] and triethylenetetramine [464], 3-formylsalicylic acid and o-hydroxybenzylamine [465], or salicylaldehyde and l-amino-2-naphthol-4-sulfonic acid [467] were used. In the example of Schiff base complexes, kinetics of formation of U(VI) complexes and their pK values were studied [468]. [Pg.463]

Tables II to X give the melting points and, where applicable, the optical rotations of the inositols, inososes, inosamines, and quercitols, and of all of their known O-substituted derivatives. Anhydroinositols, although not substitution products in the strict sense, are included, as are the carbonyl-functional derivatives of the inososes. Halogen- and nitro-substituted cyclitols, and the C-methyl-inositols and their derivatives, are not included most of these compounds are referred to in the text. The derivatives are arranged in the following order salts (inosamines) or functional derivatives (inososes), carboxylic esters, borates, nitrates, sulfonic esters, phosphates, glycosides, acetals (and Schiff bases), ethers (and IV-alkyl derivatives), and anhydrides. Tables II to X give the melting points and, where applicable, the optical rotations of the inositols, inososes, inosamines, and quercitols, and of all of their known O-substituted derivatives. Anhydroinositols, although not substitution products in the strict sense, are included, as are the carbonyl-functional derivatives of the inososes. Halogen- and nitro-substituted cyclitols, and the C-methyl-inositols and their derivatives, are not included most of these compounds are referred to in the text. The derivatives are arranged in the following order salts (inosamines) or functional derivatives (inososes), carboxylic esters, borates, nitrates, sulfonic esters, phosphates, glycosides, acetals (and Schiff bases), ethers (and IV-alkyl derivatives), and anhydrides.
Detergent-dispersant interactions at surfaces. In 4-ball wear tests, an ashless dispersant was found to have an adverse effect on ZDDP-sulfonate-carbonate hardcore RM additives. A high molecular weight Schiff base had the worst effect, followed by a bis-PIBS m-PIBS had the least adverse effect. Interactions among additives affects valve train wear. One of the effects is that a succinimide together with other additives increases the decomposition temperature of ZDDP (Ramakamur, 1994 Shirahama and Hirata, 1989). [Pg.40]

Fentanyl and its analogs are made from TV-substituted-4-piperidones [i.e., from the same intermediates of the reversed esters of pethidine (p. 266)]. These ketones condense with aniline under the influence of catalysts such as toluene-p-sulfonic acid(2) and zinc chloride(18) to give Schiff bases, which are reduced to diamines 4 by NaBH4 or LAH. Recently, the direct conversion of 4-piperidones to 4-anilino derivatives 4 has been achieved by reductive amination with aniline and sodium cyanoborohydride (NaBH3CN).(19) The diamines are acylated with propionic anhydride. [Pg.288]

The glycinate Schiff base of benzophenone 17 was also shown to be a suitable Michael donor for the asymmetric 1,6-addition to the activated dienes 44 having ketones, esters, and sulfones as substituents. Using Corey s phase-transfer catalyst, 16, the corresponding allylated products 47 were obtained as a single E-isomer with high enantioselectivity (from 92 to 98% ee). The synthetic utility of this reaction... [Pg.258]

To the original methods, like reaction of Schiff bases with chloramine or hydroxylamine-O-sulfonic acid or the simultaneous action of chloramine and ammonia on carbonyl compounds, have been added new ways, for example, the reaction of N-chloroketimines 87 with amines.101,102... [Pg.83]

The Anamination is particularly smooth when formation of a diaziridine ring occurs simultaneously with that of the N-N bond.283 284 The diaziridine ring is formed when chloramine, an Af-chloroalkylamine, or hydroxylamine-O-sulfonic acid reacts with a Schiff base or when hydroxylamine-O-sulfonic acid reacts with an aqueous solution of a ketone and an amine warming the diaziridines with aqueous acid then cleaves them to the carbonyl compounds and the substituted hydrazine ... [Pg.586]

The end-product from synthesis of a diaziridine and its fission to alkylhydrazine is the same as is obtained by direct treatment of an amine with chloramine or hydroxylamine-O-sulfonic acid, as the carbonyl component of the Schiff base is recovered however, the detour through the diaziridine is worthwhile because in the direct reaction a considerable excess of the amine must be used to suppress further reaction of the alkylhydrazine product with the animating agent, whereas the diaziridines are unaffected thereby moreover, the diaziridine route is more widely applicable. Even further, the diaziridine route avoids both the requirement for an excess of alkali and the production of the hydrazine as a very dilute aqueous solution, both of which characterize the direct reaction. Indeed it provides an effective and generally applicable synthesis of mono-284,285 and 1,1-dialkyl-hydrazines.286... [Pg.586]


See other pages where Sulfone schiff bases is mentioned: [Pg.203]    [Pg.203]    [Pg.871]    [Pg.160]    [Pg.394]    [Pg.653]    [Pg.450]    [Pg.437]    [Pg.784]    [Pg.200]    [Pg.339]    [Pg.143]    [Pg.208]    [Pg.32]    [Pg.93]    [Pg.10]    [Pg.150]    [Pg.51]    [Pg.572]    [Pg.594]    [Pg.477]    [Pg.115]    [Pg.97]    [Pg.1499]    [Pg.45]    [Pg.74]    [Pg.216]    [Pg.328]    [Pg.179]    [Pg.90]    [Pg.74]    [Pg.456]    [Pg.871]   
See also in sourсe #XX -- [ Pg.202 , Pg.203 ]




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