Methyl 4-hydroxybenzoate

One of the hydroxybenzoic acids is known by the common name salicylic acid Its methyl ester methyl salicylate occurs in oil of wintergreen Methyl salicylate boils over 50°C lower than either of the other two methyl hydroxybenzoates What is the structure of methyl salicylate Why is its boiling point so much lower than that of either of its regioisomers ... 

Iodine displacement titrations are used in pharmacopoeial assays of liquefied phenol, methyl hydroxybenzoate, propyl hydroxybenzoate and phenidione. 

Succinylcholine solutions contained 0.05% (w/v) methyl- -hydroxybenzoate as stabilizer. Phenytoin (sodium salt) and decanol were supplied by Sigma (St. Louis, MO) other materials were tricaprylylmethylammoniura chloride or Aliquat 336S (General Mills Chemicals, Inc., Kankakee, IL). Solutions of sodium phenytoin were prepared by serial dilution while keeping both pH and ionic strength at constant values, 10 and 0.1 mol/1, respectively. The selectivity coefficients were determined at pH 10.0 and 0.1 mol/1 ionic strength, both adjusted with borax-NaOH buffer solution of pH 10.0. 

Prochlorperazine Edisylate Prochlorperazine edisylate is not compatible with sodium chloride solutions containing methyl hydroxybenzoate and propyl hydroxy-benzoate as preservatives, but is compatible with solutions containing benzyl alcohol. Prochlorperazine edisylate salts are incompatible with a number of drugs such as aminophylline, amphotericin, ampicillin sodium, some barbiturates, ben-zylpenicillin salts, calcium gluconate, cefmetazole sodium, cephalothin sodium, chloramphenicol sodium succinate, chlorothiazide sodium, chloramphenicol, morphine sulfate containing phenol, magnesium trisilicate mixture, sodium succinate, chlorothiazide sodium, dimenhydrinate, heparin sodium, hydrocortisone sodium succinate, midazolam hydrochloride, and some sulfonamides.166... 

Synonyms. Sodium Methylparaben Soluble Methyl Hydroxybenzoate. Proprietary Name. Nipagin M Sodium C8H7Na03 = 174.1 CAS—5026-62-0... 

Methyl Hydroxybenzoate 133d Hydroxyurea 141-144 Acebutolol Hydrochloride... 

Isopropyl Alcohol 1180 Benzoic Acid 1419 Methyl Hydroxybenzoate... 

Propylene glycol Methyl / -hydroxybenzoate 11 Rubino and Obeng (1991). 46.8... 

BP Methyl hydroxybenzoate JP Methyl parahydroxybenzoate PhEur Methylis parahydroxybenzoas USPNF Methylparaben... 

Synonyms methyl 4-hydroxybenzoate potassium salt potassium methyl hydroxybenzoate. 

Synonyms E219 methyl 4-hydroxybenzoate sodium salt sodium methyl hydroxybenzoate soluble methyl hydroxybenzoate. 

Column yBondapak C18 (300x3.9 mm ID), mobile phase methanol - water (2 3) containing 0.005 H heptanesulfonic acid (pH 3.6), flow rate 1 ml/min, detection UV 235 nm and 292 nm. Peaks 1, pilocarpine 2, salicylate 3, methyl- -hydroxybenzoate 4, physostigmine 5, propyl- -hydro-xybenzoate. (see also Table 8.7)... 

Methyl-4-hydroxybenzene. See p-Cresol Methyl hydroxybenzoate Methyl 2-... 

Methoxycarbonyl) phenol Methyl hydroxybenzoate Methyl 2-hydroxybenzoate Methyl o-hydroxybenzoate Oil of wintergreen Sweet birch oil Synthetic oil of wintergreen Teaberry oil Wintergreen oil Classification Aromatic organic compd. 

Goodwin et al. 271) have found methyl / -hydroxybenzoate (69) as a constituent of the vaginal secretion from female dogs and proposed that it acts as a male attractant, but Kruse and Howard have challenged this conclusion 306). 

Methyl hydroxybenzoate has an unfavourable partition coefficient. Therefore it is not a suitable preservative for o/w emulsions. It is mainly used in hydrogels. In some countries a combination with propyl hydroxybenzoate is used as Preserved water . A typical mixture contains 0.075 % of methyl parahydroxybenzoate and 0.025 % of propyl parahydroxybenzoate in purified water. 

Propylene glycol acts as a preservative in concentrations above 20 % of the aqueous phase. However, it is less active than sorbic acid and methyl hydroxybenzoate. It is most effective in combination with surfactants (especially hydrophilic) and other components of creams and emulsions. Cream Base DAC (Table 12.6) is an example. It contains 20 % of propylene glycol in the aqueous phase and macrogol 20 glycerol monostearate as hydrophilic surfactant. It is well preserved in this way. 

Because of the presence of water a preservative should be added to hydrogels, see Sect. 12.5.3. Suitable preservatives are sorbic acid, glycerol and propylene glycol. Methyl hydroxybenzoate or a combination of methyl and propyl... 

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