139756-03-9

Basic information

• Product Name: 4-(2-Ethoxy benzamido)-1-methyl-3-n-propyl pyrazole-5-carboxamide.
• Synonyms: 4-(2-Ethoxy benzamido)-1-methyl-3-n-propyl pyrazole-5-carboxamide.;Sildenafil CarboxaMide IMpurity;4-[(2-Ethoxybenzoyl)aMino]-1-Methyl-3-propyl-;Sildenafil Di-AMide IMpurity;4-(2-Ethoxybenzamido)-1-methyl-3-propyl-1H-pyrazole-5-carboxamide
• CAS NO: 139756-03-9
• Molecular Formula: C₁₇H₂₂N₄O₃
• Molecular Weight: 330.38158
• Product Categories: Sildenafil Citrate;Heterocycles;Impurities;Intermediates & Fine Chemicals;Pharmaceuticals
• Mol File: 139756-03-9.mol
• Article Data: 19

Chemical Properties

• Melting Point: 153-155 °C
• Boiling Point: 445.5°C at 760 mmHg
• Flash Point: 223.2°C
• Appearance: /
• Density: 1.24g/cm³
• Vapor Pressure: 3.94E-08mmHg at 25°C
• Refractive Index: 1.598
• Storage Temp.: Refrigerator
• Solubility: DMSO (Slightly), Methanol (Slightly)
• PKA: 12.65±0.70(Predicted)
• CAS DataBase Reference: 4-(2-Ethoxy benzamido)-1-methyl-3-n-propyl pyrazole-5-carboxamide.(CAS DataBase Reference)
• NIST Chemistry Reference: 4-(2-Ethoxy benzamido)-1-methyl-3-n-propyl pyrazole-5-carboxamide.(139756-03-9)
• EPA Substance Registry System: 4-(2-Ethoxy benzamido)-1-methyl-3-n-propyl pyrazole-5-carboxamide.(139756-03-9)

Safety Data

• Hazardous Substances Data: 139756-03-9(Hazardous Substances Data)

Usage

Uses

An impurity of Sildenafil (S435000) (impurity C).

InChI:InChI=1/C17H22N4O3/c1-4-8-12-14(15(16(18)22)21(3)20-12)19-17(23)11-9-6-7-10-13(11)24-5-2/h6-7,9-10H,4-5,8H2,1-3H3,(H2,18,22)(H,19,23)

Upstream product

• 134-11-2 2-ethoxybenzoic acid 
• 139756-02-8 4-amino-1-methyl-3-propyl-1H-pyrazole-5-carboxamide 
• 304435-83-4 4-amino-2-methyl-5-propyl-2H-pyrazole-3-carboxylic acid ethyl ester 
• 1023327-67-4 4-amino-4,5-dihydro-1-methyl-3-propyl-1H-pyrazole-5-carboxamide 
• 42926-52-3 2-ethoxybenzoyl chloride 
• 54090-36-7 2-propoxybenzoyl chloride 
• 865855-32-9 4-bromo-1-methyl-3-propyl-1H-pyrazole-5-carboxamide 
• 938-73-8 2-ethoxybenzamide 
• 139756-00-6 1-methyl-2-nitro-3-propyl-1H-pyrazole-5-carboxylic acid 
• 133261-07-1 1-Methyl-3-n-propylpyrazole-5-carboxylic acid ethyl ester 
• 139755-99-0 1-methyl-3-propyl-1 H-pyrazole-5-carboxylic acid 
• 36983-31-0 ethyl 3-butyrylpyruvate 
• 139756-01-7 1-methyl-4-nitro-3-propyl-1H-pyrazole-5-carboxamide 

Downstream Products

• 139755-83-2 sildenafil 
• 171599-83-0 sildenafil citrate 
• 139756-22-2 5-(5-Chlorosulphonyl-2-ethoxyphenyl)-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one 
• 139755-85-4 5-[2-ethoxy-5-[4-(2-hydroxyethyl)-1-piperazinyl-sulphonyl]phenyl}-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one 
• 139755-83-2 viagra 
• 374776-41-7 4-(2-ethoxy-5-(4-(3-ethoxycarbonylpropyl)piperidinylsulfonyl)benzamido)-1-methyl-3-n-propylpyrazole-5-carboxamide 
• 374776-45-1 4-(2-ethoxy-5-(4-(2-ethoxycarbonylethyl)piperazinylsulfonyl)benzamido)-1-methyl-3-n-propylpyrazole-5-carboxamide 
• 374776-39-3 4-(2-ethoxy-5-(4-(2-ethoxycarbonylethyl)piperidinylsulfonyl)benzamido)-1-methyl-3-n-propylpyrazole-5-carboxamide 
• 374776-43-9 4-(2-ethoxy-5-(4-(ethoxycarbonylmethyl)piperazinylsulfonyl)benzamido)-1-methyl-3-n-propylpyrazole-5-carboxamide 
• 374776-37-1 4-(2-ethoxy-5-(4-(ethoxycarbonylmethyl)piperidinylsulfonyl)benzamido)-1-methyl-3-n-propylpyrazole-5-carboxamide 
• 374776-08-6 5-(2-ethoxy-5-(4-(hydroxycarbonylmethyl)piperazinylsulfonyl)phenyl)-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one 
• 226956-42-9 4-(5-chlorosulfonyl-2-ethoxybenzamido)-1-methyl-3-n-propylpyrazole-5-carboxamide 
• 139756-21-1 5-(2-ethoxy)-phenyl-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidine-7-one 

Relevant articles and documents

Improved synthesis process of sildenafil

The invention discloses an improved synthesis process of sildenafil, belonging to the technical field of preparation of drug intermediates. In the process, high-concentration chlorosulfonic acid is prevented from being used as a reaction solvent and reagent, and 3-5 equivalent chlorosulfonic acid is used as a reaction reagent. Compared with the prior art, the process has the characteristics of economical performance, environmental protection, safety and the like, for example, equipment cannot be corroded, the post-treatment of reaction becomes simpler, the solvent is single and can be reused, product purity is high, and the like.

Preparation method of sildenafil

The invention provides a preparation method of sildenafil. The preparation method comprises the following steps: dissolving a compound III in an organic solvent I, adding a compound II for amidation reaction, washing and drying to obtain a compound IV; directly adding the solution obtained in the step S1 into a chlorosulfonic acid-thionyl chloride mixture for chlorosulfonation reaction without separation and purification, pouring ice water after the reaction is finished, layering, taking an organic phase, washing and drying to obtain a compound V; adding the compound V obtained in the S2 intoN-methyl piperazine, carrying out N-sulfonation reaction for 0-4 hours, concentrating, adding alkali and an organic solvent II, heating to carry out cyclization reaction for 2-6 hours, adding water for cooling, adding hydrochloric acid for acidification, and filtering to obtain a target compound I. A continuous method is adopted for synthesis, and the production efficiency is improved.

Sildenafil intermediate synthesis method

Sildenafil has a good effect of treating male erectile dysfunction (ED) in clinic. Many preparation methods of sildenafil have been already reported and mostly belong to two-step synthesis. The two-step post-treatment operation is relatively tedious, and yield is low. The invention provides a synthesis method of a sildenafil intermediate, comprising the following steps: dissolving a compound II inan organic aprotic solvent, and adding a compound I to carry out a condensation reaction; adding alkali to carry out a cyclization reaction after it is monitored that the compound II is completely reacted so as to obtain a compound IV. By ''one-pot'' synthesis, generation of ''three wastes (waste gas, waste water and industrial residue)'' is reduced, reaction time is greatly shortened, reaction yield is raised, and stability is good.