312-93-6Relevant articles and documents
Eudragit E100 as a drug carrier: The remarkable affinity of phosphate ester for dimethylamine
Guzman,Manzo,Olivera
, p. 2424 - 2433 (2012)
Therapeutic agents containing phosphate groups in their molecules have increasing therapeutic impact. The object of this study was to characterize the cationic polyelectrolyte Eudragit E100 (EuE100) as a carrier for drugs containing phosphate groups, using dexamethasone phosphate (DP) as a model. A series of EuE100-DP complexes was obtained by acid-base reaction in which DP neutralized 12.5-75% of the basic groups of EuE100. The solids obtained after solvent evaporation revealed by spectroscopic characterization the complete reaction between the components through the ionic interaction between the amine groups of EuE100 and the phosphate groups of DP. The reversibility of the counterion condensation, evaluated through the proton-withdrawing effect produced by the ionic exchange generated by titration with NaCl, showed a remarkable high affinity between EuE100 and DP. In line, drug delivery in bicompartimental Franz cells toward water as receptor medium was very slow (2% in 6 h). However, it was increased as water was replaced by NaCl solution, which upon diffusion generates ionic exchange. A sustained release of DP with noticeable zero order kinetics accounted for a remarkable high affinity, mainly due to the electrostatic attraction. The release rate remains constant regardless of the saline concentration of the media. Besides, the delivery control is maintained even in gastric simulated fluid, a property not informed previously for EuE100 complexes.
Trihydrate dexamethasone sodium phosphate compound and pharmaceutical composition preparation thereof
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Paragraph 0045; 0047; 0048, (2019/01/23)
The invention discloses a trihydrate dexamethasone sodium phosphate compound and a pharmaceutical composition preparation thereof. Each mole of dexamethasone sodium phosphate compound contains 3 molesof water. The trihydrate dexamethasone sodium phosphate compound which is high in purity, good in stability, high in solubility and not prone to moisture absorption is prepared by controlling the pHvalue, the devitrification temperature and the devitrification solvent system of a dexamethasone sodium phosphate solution by an inventor. The pharmaceutical composition preparation is an injection oreye drops prepared from the trihydrate dexamethasone sodium phosphate compound.
Preparation method for dexamethasone sodium phosphate
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, (2016/11/09)
The invention relates to a preparation method for dexamethasone sodium phosphate. The preparation method comprises the following steps: a ring-opening reaction is carried out, namely, dexamethasone acetate epoxide is employed as an initial raw material, HF and DMF are added, a reaction is performed for 3h, a ring-opening reaction is carried out and a dexamethasone acetate solution is prepared; recrystallization is carried out, namely, methanol is added in the dexamethasone acetate solution, recrystallization is carried out, and dexamethasone acetate is prepared; base catalysis hydrolysis is carried out, namely, dexamethasone acetate is added in Na2CO3 and methanol, a reaction is carried out for 10min, dexamethasone is prepared; pyrophosphoryl chlorine esterification is carried out, namely, dexamethasone prepared in the third step is reacted with pyrophosphoryl chlorine and THF, and dexamethasone phosphate ester is prepared; a neutralization salt forming reaction is carried out, namely, the dexamethasone phosphate ester obtainedin the fourth step is reacted with NaOH and methanol at a reaction temperature of 20 DEG C-30 DEG C for 1h, and dexamethasone sodium phosphate is prepared. The steps are simple, raw materials are easily available, the reaction conditions are mild, the method is suitable for industrial production, and the cost is low.