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ChemicalBook CAS DataBase List D-Biotin
58-85-5

D-Biotin synthesis

4synthesis methods
-

Yield:58-85-5 95%

Reaction Conditions:

Stage #1: N,N'-dibenzylbiotinwith boron tribromide in dichloromethane at -5 - 50; for 1.16667 h;Inert atmosphere;
Stage #2: with hydrogenchloride in water;Temperature;Solvent;

Steps:

1.1; 1.2; 2.1; 2.2; 3; 3.2; 4; 4.2 (1) Synthesis of crude d-biotin

In an anhydrous reaction vessel,Dissolve bis-benzyl biotin (2.13 g, 5 mmol) in 100 mLIn anhydrous dichloromethane, the air in the system is replaced with argon three times and then argon gas is protected.Instilled in an ice bath at -5 ° C1M solution of boron tribromide in dichloromethane (15 mL, 15 mmol) was reacted for 20 min, and then transferred to 25 ° C for 50 min.After monitoring the reaction completely by HPLC,The reaction system was cooled in an ice bath at 0 ° C, and quenched by adding 213 mL of saturated aqueous sodium carbonate.Rotate to remove organic solvent and addExtract 213 mL of water, 500 mL of ethyl acetate, then extract twice with water, each time 326 mL,The aqueous phase was collected and decolorized with 5 g of activated carbon for 30 min, and adjusted to pH 1-2 with concentrated hydrochloric acid.A white solid precipitated, filtered and washed with water to pH 7.A crude d-biotin was obtained.(2) Purification of crude d-biotinThe above crude product was recrystallized by adding 15 mL of pure water, stirred under reflux for 8 h, cooled, crystallized, filtered,The white crystalline powder obtained by freeze-drying and drying is pure d-biotin.The freeze-drying temperature is ≤ -30 ° C,The degree of vacuum is ≤ -10 Pa and the time is 12 hours.The obtained d-biotin mass was 1.16 g.The yield was 95.0%.

References:

CN109627254,2019,A Location in patent:Paragraph 0037; 0038; 0039; 0040; 0041; 0042; 0043-0060

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