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2- Hydroxyethyl- 3-cyclodextrin

Many CDs have been successfully used to solubilize insoluble drugs, here are a partial list of CD derivatives reported in the literature fflFCD, SBE-ft-CDs, randomly methylated-P-cyclodextrin (RM-p-CD), 2,3,6-partially methylat flcyclodextrin (PM-ft-CD), glucosyl-ft-CD (G1-P-CD), maltosyl-p-cyclodextrin (G2- -CD), hydroxyethyl-p-cyclodextrin (He-p-CD), diethyl-P-cyclodextrin (DE-p-CD)P-carboxymethyl-Qethyl- -cyclodextrin (CME-p-CD), and (2,6-oG>-methyl)-p-cyclodextrin (DOM-p-CD). [Pg.146]

Jambhekar, S., Casella, R., and Maher, T. 2004. The physicochemical characteristics and bioavailability of indomethacin fromp-cyclodextrin, hydroxyethyl-fs-cyclodextrin, and hydroxypropyl-p-cyclodextrin complexeslnt. J. Pharm.270 149-166. [Pg.156]

The approach of CMPAs has also been used in thin-layer chromatography (TLC) for the chiral resolution of a variety of racemic compounds [100-110]. Lepri et al. [104,105] used BSA as a mobile phase additive for the chiral resolution of dansyl amino acids and other drugs by TLC. Armstrong et al. [101,102] used unde-rivatized and hydroxyethyl and hydroxypropyl /I-cyclodextrins for the chiral resolution of dansyl amino acids, alkaloids, and other compounds. Aboul-Enein... [Pg.367]

An aqueous solution of 17.68 ml of water and hydroxypropylated p-cyclodextrin (1.6 mmol) was treated with 1,1-diphenylethylene (1.6 mmol). This solution was then treated with 150 g of water and 2-hydroxyethyl methacrylate (538 mmol), heated to 85°C, and further treated with the dropwise addition of ammonium peroxodisulfate (4.8 mmol) dissolved in 10 g of water. The solution temperature was next raised to 90°C, and the mixture was reacted for 5 hours. A clear orange solid was obtained having a of 5200 dal tons with a polydispersity of 1.21. [Pg.576]

Irie, T. Eukunaga, K. Yoshida, A. Uekama, K. Pales, H.M. Pitha, J. Amorphous water-soluble cyclodextrin derivatives 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxyisobu-tyl, and carboxamidomethyl derivatives of (3-cyclodextrin. Pharm. Res. 1988, 5 (11), 713-717. [Pg.695]

Hydroxyethyl-P-cyclodextrin is made by reacting P-cyclodextrin with ethylene oxide hydroxypropyl-P-cyclodextrin is made by reacting P-cyclodextrin with propylene oxide. [Pg.219]

Dimethyl-P-cyclodextrin 2-hydroxyethyl-P-cyclodextrin 2-hydroxypropyl-P-cyclodextrin 3-hydroxypropyl-P-cyclo-dextrin trimethyl-P-cyclodextrin. [Pg.219]

Surface tension 68.0-71.0 mN/m (68-71 dynes/cm) at 25°C. Comments used in applications similar to those for P-cyclodextrin. The degree of substitution of hydroxyethyl... [Pg.219]

The use of thiazolium salts enables the benzoin condensation to proceed at room temperature. It can also be performed in dipolar aptotic solvents or under phase transfer conditions. Thiazolium salts such as vitamin Bi, thiazolium salts attached to y-cyclodextrin, macrobicyclic thiazolium salts, thiazolium carboxylate, ° naphtho[2,l-d]thiazolium and benzothiazolium salts catalyze the benzoin condensation and quaternary salts of 1-methylbenzimidazole and 4-(4-chlorophenyl)-4//-1,2,4-triazole are reported to have similar catalytic activity. Alkylation of 2-hydroxyethyl-4-methyl-l,3-thiazole with benzyl chloride, methyl iodide, ethyl bromide and 2-ethoxyethyl bromide yields useful salts for catalyzing 1,4-addition of aldehydes to activated double bonds. Insoluble polymer-supported thiazolium salts are catalysts for the benzoin condensation and for Michael addition of aldehydes. Electron rich al-kenes such as bis(l,3-dialkylimidazolidin-2-ylidenes) bearing primary alkyl substituents at the nitrogen atoms or bis(thiazolin-2-ylidene) bearing benzyl groups at the nitrogen atoms are examples of a new class of catalyst for the conversion of ArCHO into ArCHOHCOAr. [Pg.543]

Naproxen Colyophilization (223K and 0.3 torr) of naproxen and hydroxyethyl-p-cyclodextrin, or hydroxypropyl-p-cyclodextrin [146]... [Pg.217]

Jambhekar S, Casella R, Maher T, The physicochemical characteristics and bioavailability of indomethacin from y -cyclodextrin, hydroxyethyl-y -cyclodextrin and hydroxypropyl-y -cyclodextrin complexes, Int. J. Pharm. 2004 270 149-166. [Pg.225]

Poly(iV,A/ -dimetltylaciylaiiiide-co-2-hydroxyethyl methaciylate) water and p-cyclodextrin 1998GOS... [Pg.220]

Hydroxyethyl methacrylate Hydroxypropyl methacrylate Monochlorotriazinyl-P-cyclodextrin Terpene resin... [Pg.4792]

Poly(A, A -dimethylacrylatnide-co-2-hydroxyethyl methaciylate) P-cyclodextrin and water 1998GOS... [Pg.454]

Cyclodextrins (a-CD, 0 CD, and y-CD) were obtained from Hayashibara Biochemical Laboratories Inc, Their purities were checked by elemental analysis and optical rotation. Ferrocene was purchased from Aldrich Chemical Co, Acetylferrocene and diacetylferrocene were prepared from ferrocene and acetic anhydride by a procedure similar to that described previously. [9] a-Hydroxyethyl ferrocene was prepared by the procedure described previously. [10]... [Pg.797]

A/-ISOpropyl Acrylamid6. Homopolymers from A(-isopropyl acrylamide (NlPAAm) are well known and have been of great interest because of their low critical solution temperature (LOST) behavior in water-solution. The polymer is soluble at low temperatures in water and precipitates above the LOST upon heating. Those kinds of polymers are potentially useful in the pharmaceutical or medical area. The homo- and copolymerization with water-soluble comonomers such as 2-hydroxyethyl methacrylate and characterization of the corresponding polymers of NlPAAm are described in some papers. In the case of copolymerization with hydrophobic comonomers, the use of an organic solvent is necessary, otherwise the polymerization has to be carried out in emulsion. But the different solubilities of the monomers in water often make the copol3unerization of water-soluble and water-insoluble monomers by classical emulsion polymerization difficult. Because of the above discussed property of cyclodextrin derivatives, these problems can be avoided if the copolymerization reactions are performed in the presence of cyclodextrin derivatives. [Pg.2047]

Armstrong, D. W., Faulkner, J. R., Jr., and Han, S. M. (1988). Use of hydroxypropyl-and hydroxyethyl-derivatized beta-cyclodextrins for the thin-layer chromatographic separation of enatiomers and diastereomers. J. Chromatogr. 452 323-330. [Pg.426]

Alak and Armstrong (107,108,112,113) investigated the influence of different silicas and binders on the separation behavior of P-cyclodextrin TLC plates. Besides nine racemates, three diastereomeric compounds and six structural isomers were separated. Wilson (109) impregnated silica plates with a 1% solution of P-CD in ethanol-dimethylsulfoxide (80 20 by volume) racemic mandelic acid was barely separated, and the antipode separation of P-blockers was not possible. Armstrong et al. (110) were the first to describe application of P-cyclodextrin as a chiral eluent additive for separations on reversed-phase TLC plates. The success of separation was strongly dependent on type and quantity of modifier applied, but above all on the concentration of P-CD. The low solubility of 3-CD in water (0.017 M, 2S C) can be improved by addition of urea sodium chloride stabilizes the binder of the RP plates. Compared to 3-CD bonded phases, a reversed retention behavior was noticed, the D-enantiomer eluting above the L-isomer. The separation of steroid epimers and other diastereomeric classes of compounds is also possible with this technique. Hydroxypropyl and hydroxyethyl P-... [Pg.634]

NEUTRAL CYCLODEXTRINS The above-mentioned native cyclodextrins, a-CD, (3-CD, and y-CD, can be considered neutral in the pH range commonly used in CE. Derivatized CDs can also be neutral when neutral groups, such as methyl, hydroxyethyl, and hydroxypropyl, are incorporated. [Pg.1555]


See other pages where 2- Hydroxyethyl- 3-cyclodextrin is mentioned: [Pg.92]    [Pg.217]    [Pg.346]    [Pg.169]    [Pg.756]    [Pg.378]    [Pg.381]    [Pg.98]    [Pg.258]    [Pg.1189]    [Pg.1206]    [Pg.1526]    [Pg.5679]    [Pg.264]    [Pg.799]    [Pg.235]    [Pg.283]    [Pg.273]    [Pg.976]    [Pg.976]    [Pg.81]    [Pg.39]    [Pg.1307]   
See also in sourсe #XX -- [ Pg.219 , Pg.756 ]




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Hydroxyethylation

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