Dexamethasone sodium phosphate, chemical name is 16α-methyl-11β, 17α, 21-trihydroxy-9α-fluoropregnane-1,4-diene-3Chemicalbook,
20-dione-21-phosphate disodium salt, is an adrenal cortical hormone drug with anti-inflammatory, anti-allergic, anti-rheumatic and immunosuppressive effects. |
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(1) Anti-inflammatory effect: It can reduce and prevent tissue response to inflammation, thereby reducing the manifestation of inflammation. It can inhibit the accumulation of inflammatory cells, including macrophages and leukocytes, at the site of inflammation, and inhibit phagocytosis, the release of lysosomes, and the synthesis and release of inflammatory chemical mediators.
(2) Immunosuppressive effect: It includes preventing or inhibiting cell-mediated immune responses, delaying chemical allergic reactions, reducing the number of T lymphocytes, monocytes, and eosinophils, reducing the binding ability of immunoglobulins to cell surface receptors, and inhibiting the synthesis and release of interleukins, thereby reducing the transformation of T lymphocytes to lymphocytes and reducing the expansion of primary immune responses. It can also reduce the passage of immune complexes through the basement membrane and reduce the concentration of complement components and immunoglobulins. |
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The preparation method of dexamethasone sodium phosphate for injection comprises the following steps:
1) Synthesis of dexamethasone sodium phosphate: using dexamethasone acetate epoxy as the starting material,
sequentially undergoing ring-opening reaction, recrystallization, base-catalyzed hydrolysis, pyrophosphoryl chloride esterification,
and neutralization salt-forming reaction to obtain dexamethasone sodium phosphate solution, and the dexamethasone sodium phosphate solution
is recrystallized again to obtain dexamethasone sodium phosphate crystals; Ring-opening reaction: using dexamethasone acetate epoxy as the starting material, adding
HF and DMF, and the reaction temperature is The temperature is -10°C, the reaction time is 3h for ring-opening reaction to obtain dexamethasone acetate solution,
and the molar ratio of dexamethasone acetate epoxide, HF, and DMF is 1:92:44; the recrystallization: methanol is added to the dexamethasone acetate solution
for recrystallization to obtain dexamethasone acetate; the base-catalyzed hydrolysis: the obtained dexamethasone acetate is added to Na2CO3 and methanol, the reaction
temperature is 20°C, and the reaction time is 10min to obtain dexamethasone, dexamethasone acetate Chemi The molar ratio of calbook pine, Na2CO3 and methanol is 1:4:214;
the pyrophosphoryl chloride esterification: the obtained dexamethasone is reacted with pyrophosphoryl chloride and THF to obtain dexamethasone phosphate,
and the molar ratio of dexamethasone, pyrophosphoryl chloride and THF is 1:5:19; the neutralization salt-forming reaction:
the obtained dexamethasone phosphate is reacted with NaOH and methanol, the reaction temperature is 20°C,
the reaction time is 1h to obtain dexamethasone sodium phosphate, dexamethasone phosphate,
NaO H, methanol in a molar ratio of 1:2:169; 2), the dexamethasone sodium phosphate crystals obtained in step 1) are dried and ball-milled into powder;
3), dexamethasone sodium phosphate is uniformly mixed with glucose, disodium hydrogen phosphate, and sodium dihydrogen phosphate to form a composition,
and the weight ratio of dexamethasone sodium phosphate to disodium hydrogen phosphate is 1::0.01;
4), the mixed composition in step 3) is dissolved in prescription water for injection, and then a prescription amount of ethanol is added,
and activated carbon is added, and the mixture is kept at 60°C for 30 minutes. |
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Dexamethasone inhibits IL-1-induced COX-2 mRNA expression in human articular chondrocytes.
In MC3T3-E1 cells, dexamethasone inhibits tumor necrosis factor alpha (TNFα)-induced cyclooxygenase-2 with an IC50 of 1 nM.
Dexamethasone binds to the glucocorticoid receptor and subsequently to the glucocorticoid response element.
Dexamethasone (10 μM) induces osteoblastic differentiation in rat bone marrow stromal cell cultures and increases the mRNA expression of alkaline phosphatase osteocalcin,
bone sialoprotein, and osteocalcin. Dexamethasone (5 μM) treatment reduces differentiation of human hippocampal neural precursor cells and SRE-driven gene expression. |
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In male Fischer F344 rats, Dexamethasone (2 mg/kg) reduced the number of BrdU-labeled hepatocytes by 80%.
In male Fischer F344 rats, pretreatment with Dexamethasone (2 mg/kg) simultaneously inhibited the expression of TNF and IL-6 after partial
hepatectomy and significantly reduced the proliferative response of hepatocytes. Dexamethasone also severely reduced the induction and expansion of oval
cells induced by the 2-acetylaminofluorene/partial hepatectomy (AAF/PH) regimen, but had no effect on the proliferation of biliary cells stimulated by bile duct ligation.
In Sprague-Dawley rats, Dexamethasone (100 μg/kg) significantly reduced the number of BrdU(+) hippocampal progenitor cells by 59.2%. In Sprague-Dawley rats,
Dexamethasone (100 μg/kg) reduced the activation of ERK in the granulosa cell layer. |
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Adrenal cortical hormone drugs. It has anti-inflammatory, anti-toxic, anti-allergic and glucose metabolism effects.
It is used for inflammatory and allergic diseases, bovine ketoacidosis and sheep pregnancy toxemia, etc. |
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