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ChemicalBook CAS DataBase List Cefuroxime
55268-75-2

Cefuroxime synthesis

6synthesis methods
Cefuroxime, (Z)-mono(O-methyloxim) (6R,7R)-7-[2-(2-furyl)glyoxylamido]- 3-(hydroxymethyl)-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-en-2-carboxylic acid carbamate (32.1.2.18), is synthesized from 2-acetylfuran. Oxidizing this compound with nitrous acid gives 2-furylglyoxalic acid (32.1.2.15), which is reacted with methoxylamine to give the corresponding oxime, syn-2-methoxyamino-2-(2-furyl)acetic acid (32.1.2.16), which is then transformed into a mixed anhydride when reacted with oxaloyl chloride in diemethylformamide, and then reacted with benzhydryl ester of 7-aminocephalosporanic acid. The resulting product (32.1.2.17) undergoes enzymatic hydrolysis in an alkaline medium, in which the benzhydryl protection is not affected, and only the acetoxy group of the molecule at position C3 of the aminocephalosporanic acid is hydrolyzed. The resulting product with a free hydroxymethyl group (32.1.2.18) is reacted with chlorosulfonyl isocyanate, with intermediate formation of the corresponding N-chlorosulfonyl urethane (32.1.2.19), which is hydrolyzed by water to the urethane (32.1.2.20). Finally, removal of the benzhydryl protection using trifluoroacetic acid gives the desired cefuroxime (32.1.2.21).

Another simpler way of the synthesis of cefuroxime is by direct acylation of 7-amino- 3-aminocarbonyloxymethyl-3-cefem-4-carboxylic acid (32.1.2.22), which is isolated from the cultural fluid of Streptomyces lactamdurans, using syn-2-methoxyamino-2- (2-furyl)acetic acid chloride, which is synthesized by reacting the corresponding acid with phosphorous pentachloride.
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Yield:55268-75-2 95%

Reaction Conditions:

Stage #1:isocyanate de chlorosulfonyle;(6R,7R)-7-[2-(2-furyl)-2-(methoxyimino)acetamido]-3-hydroxymethyl-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid in dimethylcarbonate at 0 - 5;
Stage #2: with hydrogenchloride;water in dimethylcarbonate at 10 - 15;Product distribution / selectivity;

Steps:

1
EXAMPLE 1; [00022] A 1:1 solution of chlorosulfonyl isocyanate (2.4 ml) in dimethylcarbonate was dropped into a suspension of (6R,7R)-7-[[2-furanyl(sin-methoxyimino)acetyl]amino]-3-hydroxymethyl-ceph-3-em-4-carboxylic acid (3.6 g) in dimethylcarbonate (35 ml) cooled to 0-4° C., under inert atmosphere, keeping the temperature below 5° C. [00023] When the addition of the reactive was completed, the mixture was kept at 0÷5° C. until the starting substrate was completely converted. [00024] 18% Hydrochloric acid (35 ml) was then added, keeping the heterogeneous mixture at a temperature ranging from 10 to 15° C. until the synthesis intermediate was completely hydrolysed. [00025] Cefuroxime acid was recovered by filtration in the form of a white crystalline powder (3.8 g) in a 95% yield, or Cefuroxime sodium salt was recovered by the method described in U.S. Pat. No. 4,775,750 in similar yields. [00026] The recovered product had high HPLC purity (>95%), and was characterized by 1H-NMR, 13C-NMR and mass spectroscopies, which gave the same data as those reported in literature for Cefuroxime.

References:

Antibioticos S.p.A. US6642378, 2003, B1 Location in patent:Page/Page column 2-3

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