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ChemicalBook CAS DataBase List (2S-cis)-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid
87-53-6

(2S-cis)-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid synthesis

5synthesis methods
-

Yield: 88%

Reaction Conditions:

Stage #1:6-Aminopenicillanic Acid with sulfuric acid;sodium nitrite in water at -10 - 5; for 1 h;
Stage #2: with sodium hypophosphite in water at -5 - 30; for 2 h;

Steps:

1 Example 1: Preparation of (2S,5R)-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid
Add 100g of 6-APA to 366g of 50% dilute sulfuric acid,Cool down to -5 °C. A solution of 123 g of sodium nitrite (43 g of sodium nitrite dissolved in 80 g of water) was added dropwise at a temperature of -10 to 0 °C. After the completion of the dropwise addition, the mixture was kept at -5 to 5 ° C for 1 hour. 177g sodium hypophosphite solution (57g sodium hypophosphite dissolved in 120g water) was added dropwise at a temperature of -5 to 5 °C.The temperature was raised to 20-30 ° C for 2 hours. After adding 1.2 L of dichloromethane and stirring for 0.5 hour, the mixture was allowed to stand for stratification. The organic phase was washed with 80 g of a saturated sodium hydrogencarbonate solution, and then evaporated to dryness under reduced pressure, then methanol was added and stirred at 20-30 ° C for 3 hours.Filtration of 82 g of white solid (2S,5R)-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid (Compound 1) The yield was 88%.

References:

Qilu Tianhe Huishi Pharmaceutical Co., Ltd.;Qilu Tianhe Huishi (Leling) Pharmaceutical Co., Ltd.;Li Zhifeng;Zheng Changsheng;Wu Zhaoshen;Yang Qingkun;Li Zhuohua CN109503628, 2019, A Location in patent:Paragraph 0034; 0035

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