Pyrazole compound and its preparation method and use
A compound, pyrazole technology, applied in the field of medicine and medicinal chemical synthesis, can solve the problems of rapid mutation, acceleration and urgency of influenza virus
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0033] Synthesis of N-(substituted benzisothiazole)-2(3H)-carboxamide (A)
[0034]
[0035] Step 15 - Synthesis of Amylhydantoin (a1)
[0036] Add hydantoin (1g, 10mmol) and 3-pentanone (1.29g, 15mmol) in sequence in a single-necked bottle, stir, heat up to 55°C, add ethanolamine (0.475g, 7.8mmol) dropwise, and heat up to 115 ℃ nitrogen protection reflux reaction for 6-10 hours, the reaction is completed, cooled to room temperature, the reaction system is brownish yellow, with a small amount of white crystals precipitated. Subsequently, about 2 times the volume of water was added to the reaction system, and the pH was adjusted to 4 with 6M hydrochloric acid, and a large amount of white crystals were precipitated in the reaction system. Filter, wash the filter cake with water, and dry to obtain a 11.04 g white crystalline solid with a yield of 62%.
[0037] 1 H NMR (400MHz, DMSO-d 6)δppm10.81(s,1H),9.76(s,1H),2.60(q,J=7.4Hz,2H),2.14(q,J=7.6Hz,2H),0.97(t,J=7.6Hz, 6H); 1...
Embodiment 2
[0067] Synthesis of 4-(p-toluenesulfonyloxymethyl)-2-oxazolidinone (B)
[0068]
[0069] Step 12-Synthesis of methyl oxazolidinone-4-carboxylate (b-1)
[0070] Weigh serine methyl ester hydrochloride (800mg, 5.16mmol) in a two-necked bottle, add 6mL of anhydrous dichloromethane to the reaction solution under nitrogen protection, stir to dissolve completely, add redistilled triethylamine under ice bath stirring, After reacting for 15 minutes, under the protection of nitrogen, 2 mL of anhydrous dichloromethane mixed solution of triphosgene (1.531 g, 5.16 mmol) was added dropwise. The reaction is almost complete. Add 20 mL of diethyl ether to the reaction system, freeze in the refrigerator for 30 minutes, and then filter, then freeze the filtrate in the refrigerator, filter, collect the filtrate, concentrate, and purify by silica gel column chromatography (petroleum ether: ethyl acetate = 1:2) to obtain Pale yellow oil b-1 627mg, yield 84%.
[0071] 1 H NMR (400MHz, CDCl ...
Embodiment 3
[0080] Synthesis of 4-biphenylbenzyl bromide (C)
[0081]
[0082] The first step: the preparation of 4-biphenyl benzyl alcohol (c1)
[0083] In a 50mL round-bottomed flask, dissolve 4-biphenylcarbaldehyde (365mg, 2mmol) in 10mL of methanol, add sodium borohydride (151mg, 4mmol) in batches under ice-bath conditions, and then turn the reaction system to room temperature for 45 minutes , TLC monitors that the reaction is complete. After the solvent was removed from the reaction system, 10 mL of dichloromethane was added, washed with water (2×10 mL), the organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated to obtain a yellow powdery crude product c1, which could be used for direct injection into the next step.
[0084] 1 H NMR (CDCl 3 ,400MHz)δ7.62-7.59(m,4H),7.48-7.43(m,4H),7.39-7.34(m,1H),4.74(br,2H).
[0085] The second step: the preparation of 4-biphenylbenzyl bromide (C)
[0086] In a 50mL round bottom flask, ...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More