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ChemicalBook CAS DataBase List Cemandil sodium salt
42540-40-9

Cemandil sodium salt synthesis

5synthesis methods
-

Yield:42540-40-9 96.3%

Reaction Conditions:

Stage #1:(6R,7R)-7-amino-3-[(1H-1-methyltetrazol-5-yl)thio]methylceph-3-em-4-carboxylic acid with N,O-bis-(trimethylsilyl)-acetamide in ethyl acetate at 25 - 28;
Stage #2:(S)-formyloxy(phenyl)acetyl chloride in ethyl acetate at 0 - 5; for 2 h;
Stage #3: with sodium hydrogencarbonate; pH=5.5 - 6.5Solvent;Temperature;

Steps:

1; 2 Example 1
Add 32.8g (0.1mol) of 7-ATCA and 200ml of ethyl acetate into a dry 500ml four-neck flask, control the temperature at 25-28 °C, add 40.8g (0.2mol) of BSA and stir the reaction for 4-6 h until it is clear; Cool down to 0-5 °C, add 23.8g (0.12mol) of L-formylmandelic acid chloride dropwise, stir and react for 2 h; After the 7-ATCA residue is less than 1.5mg/ml qualified, add 150ml of cold water at 0-10 °C. After stirring for 10 minutes, separate the layers, separate the water phase, and wash the organic phase with 100ml water and 100ml 20wt% sodium chloride solution in turn, then add 1.5g activated carbon and stir to decolorize for 1h;After filtering, washing with 50 ml of ethyl acetate, controlling the temperature of the organic phase within 45 °C and distilling to dryness under reduced pressure, 47.2 g of L-form cefmendol acid was obtained with a yield of 96.3%. Take 20g of L-form cefmendol acid and add 70g of 5% sodium bicarbonate solution dropwise,Control the PH value between 5.5 and 6.5, and use the BK-FD10S Brocade vacuum freeze dryer to freeze and dry at -45 to -40°C to obtain 20.5 g of product with a yield of 98%. Detection specific rotation: +36.5°.

References:

CN112694488, 2021, A Location in patent:Paragraph 0057-0064

FullText

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