Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Mannitol chloride

For complete acetylation of polyhydric compounds, such as glucose (p. 141) and mannitol (p. I42), even undiluted acetic anhydride is insufficient, and a catalyst must also be employed. In such cases, the addition of zinc chloride or anhydrous sodium acetate to the acetic anhydride usually induces complete acetylation. ... [Pg.107]

Mannitol, CH,0H(CH0Hi4CH40H, is a hexahydric alcohol obtained by the reduction of mannose. Since ring formation does not occur in mannitol, the hexacetyl derivative can exist in only one form, and therefore either zinc chloride or sodium acetate can be used as a catalyst for the acetylation. [Pg.142]

Required Mannitol, 5 g. acetic anhydride, 30 ml. zinc chloride, ca, 0-5 g. [Pg.143]

J The hexa.acetyl derivative, m.p. 121°, may be prepared as follows. Boil under reflux 1 part of mannitol with 5 parts by weight of acetic anhydride and 1 part of anhydrous sodium acetate or with a little anhydrous zinc chloride for 15-20 minutes, pour into excess of water, stir the mixture until the oil has solidifled, and then recrystallise from methylated spirit. [Pg.448]

The apparent acid strength of boric acid is increased both by strong electrolytes that modify the stmcture and activity of the solvent water and by reagents that form complexes with B(OH) 4 and/or polyborate anions. More than one mechanism may be operative when salts of metal ions are involved. In the presence of excess calcium chloride the strength of boric acid becomes comparable to that of carboxyUc acids, and such solutions maybe titrated using strong base to a sharp phenolphthalein end point. Normally titrations of boric acid are carried out following addition of mannitol or sorbitol, which form stable chelate complexes with B(OH) 4 in a manner typical of polyhydroxy compounds. EquiUbria of the type ... [Pg.193]

Chemical Reactions. Mannitol is regenerated by treatment of the hexanitrate with Amm sulfide (Ref 6), iron in acet ac (Ref 7), ferric chloride (Ref 14), or with hydrogen iodide... [Pg.31]

Maltodextrin 182 Maltose 164,165, 181-184 Mandelin s reagent 426 Manganese cations 144 Manganese(II) chloride reagent 333 Mannitol 409,410 Marking the front 132 Marmesin 67 Marquis reaction 352 Marquis reagent 299 Matacil 107... [Pg.731]

In media selective for enterobacteria a surface-active agent is the main selector, whereas in staphylococcal medium sodium and lithium chlorides are the selectors staphylococci are tolerant of salt concentrations to around 7.5%. Mannitol salt, Baird-Parker (BP) and Vogel-Johnson (VJ) media are three examples of selective staphyloccocal media. Beside salt concentration the other principles are the use of a selective carbon source, mannitol or sodium pyruvate together with a buffer plus acid-base indicator for visualizing metabolic activity and, by inference, growth. BP medium also contains egg yolk the lecithin (phospholipid) in this is hydrolysed by staphylococcal (esterase) activity so that organisms are surrounded by a cleared zone in the otherwise opaque medium. The United States Pharmacopeia (1990) includes a test for staphylococci in pharmaceutical products, whereas the British Pharmacopoeia (1993) does not. [Pg.19]

Hypertonic sahne is actively excluded from an intact BBB and also acts to draw water into the intravascular space by the creation of a sodium gradient. Various concentrations have been evaluated, with continuous sodium chloride infusions ranging from 3% to 9%, and bolus infusions up to 23.4% administered over 20 minutes in a 30 mL solution. When a continuous infusion is used, the serum sodium is typically titrated to the 155-160 range. Sodium levels above this range raise the concern for seizures and other toxic side effects. Hypertonic saline may hold an advantage over mannitol, as it has been found in animal models to decrease edema in both... [Pg.174]

C7Hu06 Na+ Cl 2,5-O-Methylene-D-mannitol sodium chloride MMANSC 37 379... [Pg.385]

Few tablets intended for oral administration are totally soluble in aqueous media, but if such a product is needed, then soluble excipients are employed. These include dextrose, lactose, mannitol, and sodium chloride, with the last of these sometimes acting as its own lubricant. Urea may also be used, but due to its known pharmacological effects, it is less desirable than the other soluble compounds cited. [Pg.300]

Using regression analysis on a data set of about 50 different molecules, it was found that a. = —4.4,8 = —0.5, Df = 12 cm2/s, and =2.5x 10 5 cm2/s [192], A graphic representation of the effect of relative molecular mass (Mr) and distribution coefficient on corneal permeability is shown in Fig. 13. One observes a rapid reduction in permeability coefficient with decreasing P and increasing Mr. The addition of pores to the model, a mathematical construct, is necessary to account for permeability of polar molecules, such as mannitol and cromolyn. These would also be required for correlating effects of compounds, such as benzalkonium chloride, which may compromise the... [Pg.442]

Miiller and Vargha65 reported that treatment of 1,6-di-O-benzoyl-D-mannitol (29) with p-toluenesulfonyl chloride gave 2,5-anhydro-l,6-di-0-benzoyl-3,4-di-0-p-tolylsulfonyl-D-glucitol (67). The formation of this compound may be the result of a favored p-toluenesulfonyla-tion at the 2(5)-hydroxyl group, followed by intramolecular cycliza-tion and subsequent esterification by the excess of the reagent. This... [Pg.128]

Summarizing, it appears that D-mannitol with boiling hydrochloric acid first suffers dehydration between Cl and C4 (because when the treatment is interrupted after only a few hours duration, 1,4-anhydro-D-mannitol is obtained), then between C3 and C6. The dehydration is probably achieved by the catalytic influence of the chloride ion. Dehydration is accompanied by the formation of smaller amounts of other ring compounds and by substitution of secondary hydroxyl groups by chlorine. With fuming hydrochloric acid, D-mannitol gives mainly 1,6-dichloro-... [Pg.223]

Fmctose and sodium chloride injection Magnesium sulfate injection Mannitol injection... [Pg.217]

Mannitol in sodium chloride injection Potassium acetate injection Potassium chloride injection Potassium chloride in dextrose injection Potassium chloride in dextrose and sodium chloride injection... [Pg.217]

Osmolarity of perfusate solution The buffer osmolarity should be standardised to facilitate estimation of Peff values. Generally adjusted to physiological conditions of 290 mOsm/kg. (70 mM phosphate buffer) with 5.4 mM potassium chloride, 48 mM sodium chloride, 35 mM mannitol, and 10 mM D-glucose. Lane et al. [131] demonstrated the effect of hypersomolar perfusion on Tapp of ibuprofen in the in situ rat gut technique. Hypersomolar solutions tended to decrease Peff values, attributable to a reversed solvent drag effect. [Pg.63]

Isotonic agents (osmolality 285-290 mOSm)—mannitol, sucrose, glycine, glycerol, and sodium chloride... [Pg.167]

Small amounts of surfactants may be used to prevent aggregation of proteins and may enhance the refolding process when the dried protein dissolves. Buffers may also help to prevent aggregation of the dissolved drug. Similarly, polymers may be used as aggregation inhibitors or to form matrices. Chan et al. [86] prepared crystalline powders of recombinant human deoxyribonuclease with high fractions of sodium chloride. These powders were formulated as adhesive mixtures on lactose and mannitol and showed improved aerosolization behaviour compared to the pure protein. [Pg.73]

Physically and chemically compatible up to 48 hours- Cimetidine mannitol potassium acetate potassium chloride potassium phosphate. [Pg.1393]

The organic esters have a greater order of stability, but it is difficult to prepare completely acylated compounds without concurrently anhy-drizing the hexitol unless one uses acid anhydrides or chlorides. Early attempts to prepare higher aliphatic esters of D-mannitol resulted in the formation of mixtures of mannitans and mannides. It is for this reason that caution must be exercised in interpreting some of the work in the literature. The analytical values of the pure compounds and the mixtures are such that one cannot differentiate between them. [Pg.220]

Some interesting resins have been obtained from the dianhydrides through their acrylic or methacrylic esters. Thus, 2,5-dimethacrylyl-l,4 3,6-dianhydro-mannitol (XIX) was formed by treating dianhydro-mannitol with methacrylyl chloride in the presence of sodium hydroxide. The product, a crystalline compound, polymerized extremely rapidly to a colorless, transparent, infusible resin. The corresponding sorbitol derivative, however, was an oil which polymerized to a softer resin. On the other hand, 2,5-diacrylyl-l,4 3,6-dianhydro-sorbitol (XX) was a crystalline compound, which polymerized to a hard, infusible, glass-like resin. [Pg.304]

Elemental composition B 17.50%, H 4.88%, O 77.62%. Boric acid may be analysed by adding calcium chloride (in excess) and sorbitol or mannitol to its solution, followed by acid-base titration using a strong base to phenolph-thalein endpoint. Elemental boron may be analyzed by AA or ICP spectrophotometry. [Pg.120]


See other pages where Mannitol chloride is mentioned: [Pg.143]    [Pg.35]    [Pg.51]    [Pg.51]    [Pg.52]    [Pg.448]    [Pg.258]    [Pg.109]    [Pg.125]    [Pg.324]    [Pg.13]    [Pg.73]    [Pg.220]    [Pg.222]    [Pg.223]    [Pg.237]    [Pg.4]    [Pg.193]    [Pg.56]    [Pg.230]    [Pg.185]    [Pg.91]    [Pg.94]    [Pg.615]    [Pg.222]    [Pg.347]   
See also in sourсe #XX -- [ Pg.73 ]




SEARCH



Mannitol

© 2024 chempedia.info