- Eudragit E100 as a drug carrier: The remarkable affinity of phosphate ester for dimethylamine
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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.
- Guzman,Manzo,Olivera
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- TARGETED STEROID CONJUGATES
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A compound of the formula (I): G1-L-G2, or a pharmaceutically acceptable salt, polymorph, prodrug, solvate or clathrate thereof, wherein G1 is a folate radical, an antifolate radical, or a folate analog radical; L is a linker; and G2 is a radical of a steroid; compositions comprising such compounds; and the use of such compounds and compositions to treat, for example, inflammation associated with a disease or disorder.
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Paragraph 00324
(2021/07/17)
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- Trihydrate dexamethasone sodium phosphate compound and pharmaceutical composition preparation thereof
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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.
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Paragraph 0045; 0047; 0048
(2019/01/23)
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- A kind of improved dexamethasone sodium phosphate intermediates
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The invention provides an improved preparation method of a dexamethasone sodium phosphate intermediate. The improved preparation method of the dexamethasone sodium phosphate intermediate comprises the following steps: (a) in tetrahydrofuran, with dexamethasone and pyrophosphoryl chloride as raw materials, carrying out a reaction at the temperature ranging from minus 35 DEG C to minus 45 DEG C, so that dexamethasone phosphate is obtained; (b) adding purified water, carrying out hydraulic analysis after a termination reaction is finished, and then adding sodium hydrogen carbonate for salifying; (c) filtering, and carrying out reduced pressure concentration at the temperature of 30-45 DEG C until tetrahydrofuran is not contained in filtrate; (d) adding an organic solvent for extraction; and (e) filtering, carrying out reduced pressure concentration at the temperature of 30-45 DEG C until the organic solvent is not contained in the filtrate, adding acid for acidification, stirring for 6-8 hours, filtering, and carrying out vacuum drying, so that dexamethasone phosphate is obtained. The improved preparation method of the dexamethasone sodium phosphate intermediate has the advantages that utilization rate of raw materials and purity and yield of a product are improved, so that production cost is reduced; and the improved preparation method of the dexamethasone sodium phosphate intermediate has a wide industrial application prospect.
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Paragraph 0040; 0041; 0042; 0043; 0044; 0045; 0046
(2017/08/25)
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- Preparation method for dexamethasone sodium phosphate
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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.
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- Discovery of Pyrophosphate Diesters as Tunable, Soluble, and Bioorthogonal Linkers for Site-Specific Antibody-Drug Conjugates
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As part of an effort to examine the utility of antibody-drug conjugates (ADCs) beyond oncology indications, a novel pyrophosphate ester linker was discovered to enable the targeted delivery of glucocorticoids. As small molecules, these highly soluble phosphate ester drug linkers were found to have ideal orthogonal properties: robust plasma stability coupled with rapid release of payload in a lysosomal environment. Building upon these findings, site-specific ADCs were made between this drug linker combination and an antibody against human CD70, a receptor specifically expressed in immune cells but also found aberrantly expressed in multiple human carcinomas. Full characterization of these ADCs enabled procession to in vitro proof of concept, wherein ADCs 1-22 and 1-37 were demonstrated to afford potent, targeted delivery of glucocorticoids to a representative cell line, as measured by changes in glucocorticoid receptor-mediated gene mRNA levels. These activities were found to be antibody-, linker-, and payload-dependent. Preliminary mechanistic studies support the notion that lysosomal trafficking and enzymatic linker cleavage are required for activity and that the utility for the pyrophosphate linker may be general for internalizing ADCs as well as other targeted delivery platforms.
- Kern, Jeffrey C.,Cancilla, Mark,Dooney, Deborah,Kwasnjuk, Kristen,Zhang, Rena,Beaumont, Maribel,Figueroa, Isabel,Hsieh, SuChun,Liang, Linda,Tomazela, Daniela,Zhang, Jeffrey,Brandish, Philip E.,Palmieri, Anthony,Stivers, Peter,Cheng, Mangeng,Feng, Guo,Geda, Prasanthi,Shah, Sanjiv,Beck, Andrew,Bresson, Damien,Firdos, Juhi,Gately, Dennis,Knudsen, Nick,Manibusan, Anthony,Schultz, Peter G.,Sun, Ying,Garbaccio, Robert M.
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p. 1430 - 1445
(2016/02/18)
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- PHOSPHATE BASED LINKERS FOR INTRACELLULAR DELIVERY OF DRUG CONJUGATES
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Phosphate-based linkers with tunable stability for intracellular delivery of drug conjugates are described. The phosphate-based linkers comprise a monophosphate, diphosphate, triphosphate, or tetraphosphate group (phosphate group) and a linker arm comprising a tuning element and optionally a spacer. A payload is covalently linked to the phosphate group at the distal end of the linker arm and the functional group at the proximal end of the linker arm is covalently linked to a cell-specific targeting ligand such as an antibody. These phosphate-based linkers have a differentiated and tunable stability in blood vs. an intracellular environment (e.g. lysosomal compartment).
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Page/Page column 53
(2015/11/18)
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