成人免费xx,国产又黄又湿又刺激不卡网站,成人性视频app菠萝网站,色天天天天

Welcome to chemicalbook!
Chinese English Japanese Germany Korea
400-158-6606
Try our best to find the right business for you.
Do not miss inquiry messages Please log in to view all inquiry messages.

Welcome back!

ChemicalBook CAS DataBase List 1,4-DIHYDRO-2-(METHYLTHIO)-4-OXO-5-PYRIMIDINE-CARBOXYLATE ACID ETHYL ESTER
53554-29-3

1,4-DIHYDRO-2-(METHYLTHIO)-4-OXO-5-PYRIMIDINE-CARBOXYLATE ACID ETHYL ESTER synthesis

2synthesis methods
Methylthiourea sulfate (75.2g, 0.4mol) was added to 16% NaOH (250mL, 1.18mol) solution and stirred for 30min, then diethyl ethoxymethylenemalonate (103.4g, 0.48 mol) was dissolved in 160 mL of ethanol and slowly dropped into the reaction solution. After the dropwise addition was completed, the reaction was carried out at room temperature for 10 h.When a large amount of white solid was precipitated, carry out suction filtration, wash with water, and vacuum dry to obtain a white solid (84.7g, 99.7%); ESE-MS (m/z): 249[M+H]+, 236.9[M+Na]+ , after verification, the product is 1,4-dihydro-2-methylmercapto-4-oxo-5-pyrimidinecarboxylic acid ethyl ester.
-

Yield:53554-29-3 99.7%

Reaction Conditions:

Stage #1: carbamimidothioic acid methyl esterwith sodium hydroxide in ethanol; for 0.5 h;
Stage #2: diethyl 2-ethoxymethylenemalonate in ethanol at 20; for 10 h;Time;

Steps:

1.1 A method for preparing avervavir comprising the following steps:

S1, methylthiourea sulfate(75.2g, 0.4mol)Add to a mass fraction of 16% NaOH (250 mL, 1.18 mol) and stir for 30 min.Then diethyl ethoxymethylenemalonate (103.4 g, 0.48 mol)Soluble in 160mL of ethanol and slowly drip into the reaction solution,After the completion of the dropwise addition, the reaction was carried out at room temperature for 10 hours, when a large amount of white solid precipitated,Pumping,Washed,Drying in vacuo gave a white solid (84.7 g, 99.7%);

References:

CN108707141,2018,A Location in patent:Paragraph 0027; 0028; 0029; 0038; 0047

1,4-DIHYDRO-2-(METHYLTHIO)-4-OXO-5-PYRIMIDINE-CARBOXYLATE ACID ETHYL ESTER Related Search: