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ChemicalBook CAS DataBase List Cefdinir
91832-40-5

Cefdinir synthesis

2synthesis methods
79349-82-9 Synthesis
7-AVCA

79349-82-9
234 suppliers
$10.00/250mg

143183-03-3 Synthesis
(Benzothiazol-2-yl)-(Z)-2-trityloxyimino-2-(2-aminothiazole-4-yl)-thioacetate

143183-03-3
103 suppliers
$680.00/1g

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Yield:91832-40-5 85.8%

Reaction Conditions:

Stage #1:(6R,7R)-7-amino-3-vinyl-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid;S-(2-benzothiazolyl) 2-(2-aminothiazol-4-yl)-2(Z)-trityloxyiminothioacetate with triethylamine in N,N-dimethyl acetamide at 15 - 20; for 4 h;
Stage #2: with hydrogenchloride;methoxybenzene in dichloromethane;N,N-dimethyl acetamide at -15 - -10; for 2 h;

Steps:

1 Example 1
In a dry reaction flask, add 30g 7-AVCA, 85g cefdinir side chain active ester and 100 ml dimethylacetamide. Control temperature at 15 °C -20 °C. Add dropwise 30g triethylamine. Stir the reaction for 4h. The reaction completely becomes clear. After the reaction is complete, add 250 ml dichloromethane. Lower the temperature to -15 °C - -10 °C. Add 50 ml anisole. Place dry hydrogen chloride gas. After about 2h, HPLC measured end point of the reaction, the reaction after the end of the, through N2Away excess hydrogen chloride gas in the system. Then add 100 ml H2O, dropping 10% of Na2CO3Solution, adjusting the pH value of 5.5 - 6.0, the temperature does not exceed 5 °C, layered. The aqueous phase is then added to 100 ml CH2Cl2Extraction, layered, add aqueous 3g decolorized with active carbon, the decolorization 1h after filtering, adding 500 ml water, for 2 mol/L hydrochloric acid to adjust the pH value to 2.2 - 2.4, temperature control 20 °C -25 °C, nourishing crystal 2h after filtering, washing, alcohol washing, drying, to obtain cefdinir 45g, yield 85.8%, the purity is ≥ 99%.

References:

China Union Chempharma (Suzhou) Co., Ltd.;Suzhou No.3 Pharmaceutical Factory Co., Ltd.;Zhou, Zijin;Zhang, Bo;Huang, Junhao;Chen, Feng;Luo, Xinzu;Yang, Long;Hu, Liyong;Wang, Lei CN106279207, 2017, A Location in patent:Paragraph 0030; 0031; 0032

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