- Green Synthesis and Antimicrobial Activity of Some Novel N-Arylimidazo[1,2-a]pyrazine-2-Carboxamide Derivatives
-
The article deals with the synthesis of some novel N-arylimidazo[1,2-a]pyrazine-2-carboxamides (7a-l) by condensation reaction of imidazo[1,2-a]pyrazine-2-carboxylic acid (5) with different aliphatic/aromatic amines (6a-l) by using 1-methylimidazole, Mukaiyama’s reagent and 2-chloro-1-methylpyridinium iodide under microwave irradiation conditions. A new series of compounds 7 have been prepared from 2-iodopyrazine (1). Compound 1 on purged with ammonia gas in the presence of Cu2O and K2CO3 furnishes pyrazin-2-amine (2), which is treated with ethyl 3-bromo-2-oxopropanoate (3) to produce ethyl imidazo[1,2-a]pyrazine-2-carboxylate (4), which on hydrolysis with NaOH yields imidazo[1,2-a]pyrazine-2-carboxylic acid (5). The structures of the newly synthesized compounds have been elucidated on the basis of spectral (IR, 1H and 13C NMR and MS) and analytical data. Compounds 7a-l have also been screened for their antimicrobial activity. Some of the compounds exhibit promising antimicrobial activity.
- Jyothi, Boggavarapu,Madhavi, Nannapaneni
-
-
Read Online
- C2-Selective, Functional-Group-Divergent Amination of Pyrimidines by Enthalpy-Controlled Nucleophilic Functionalization
-
Synthesis of heteroaryl amines has been an important topic in organic chemistry because of their importance in small-molecule discovery. In particular, 2-Aminopyrimidines represent a highly privileged structural motif that is prevalent in bioactive molecules, but a general strategy to introduce the pyrimidine C2-N bonds via direct functionalization is elusive. Here we describe a synthetic platform for site-selective C-H functionalization that affords pyrimidinyl iminium salt intermediates, which then can be transformed into various amine products in situ. Mechanism-based reagent design allowed for the C2-selective amination of pyrimidines, opening the new scope of site-selective heteroaryl C-H functionalization. Our method is compatible with a broad range of pyrimidines with sensitive functional groups and can access complex aminopyrimidines with high selectivity.
- Ham, Won Seok,Choi, Hoonchul,Zhang, Jianbo,Kim, Dongwook,Chang, Sukbok
-
supporting information
p. 2885 - 2892
(2022/02/23)
-
- Novel method for synthesizing 2- amino -3,5- dibromopyrazine as well as product and application thereof
-
The invention discloses a novel method 2 - for synthesizing, amino - 333355-dibromopyrazine by reacting, with,aminopyrazine 2 - sodium hypochlorite as a raw material, and adding, amino-pyrazino,dibromopyrazine 2 - in ;amino - 3333,5-dibromopyrazine as a raw material by, hours N,N - to obtain,aminopypyrazine 1,3 - in step, as a solvent 2 - and dropping under reduced pressure. N,N - The present invention provides a novel method for synthesizing, amino-3,5-dibromopyrazine as a crude product 15 - 20 in a reduced pressure distillation condition . The present invention. discloses a process 2 - for the preparation of the product. 2 - The present invention discloses 2 - N - 3333,5-dibromopyrazino, crude, obtained by the present, invention is added dropwise to prepare 2 - lamino - 3333.5-dibromopyrazine.
- -
-
Paragraph 0042; 0060-0061; 0066; 0071; 0077; 0078
(2020/03/25)
-
- Preparation method of 2-amino substituted six-membered nitrogen-containing heterocycle complex
-
The invention discloses a preparation method of a 2-amino substituted six-membered nitrogen-containing heterocycle complex. The preparation method comprises the following steps: mix 2-fluorine substituted six-membered nitrogen-containing heterocycle complex and amidine hydrochloride salt compound, and then react under the action of a alkaline substance to obtain a 2-amino substituted six-memberednitrogen-containing heterocycle complex. Preferably, the 2-amino substituted six-membered nitrogen-containing heterocycle complex is a 2-amino pyridine compound, a 2-aminopyrimidine compound or a 2-aminopyrazine compound. Compared with the prior art, the method has the advantages of simple synthesis conditions, less reaction steps, mild reaction conditions, low cost of the catalyst used, less waste discharge and good functional group tolerance.
- -
-
Paragraph 0025; 0026; 0109
(2019/02/08)
-
- Diverse Oxidative C(sp2)-N Bond Cleavages of Aromatic Fused Imidazoles for Synthesis of α-Ketoamides and N-(pyridin-2-yl)arylamides
-
An efficient and chemoselective C(sp2)-N bond cleavage of aromatic imidazo[1,2-a]pyridine molecules is developed. A broad scope of amide compounds such as α-ketoamides and N-(pyridin-2-yl)arylamides are afforded as the final products in up to quantitative yields. Diverse C-N bond cleavages are controlled by the oxidative species used in this transformation, with various amide products afforded in a chemoselective fashion. A preliminary study indicated that some α-ketoamides exhibit anti-Tobacco Mosaic Virus activity for potential use in plant protection.
- Xu, Fangzhou,Wang, Yanyan,Xun, Xiwei,Huang, Yun,Jin, Zhichao,Song, Baoan,Wu, Jian
-
p. 8411 - 8422
(2019/05/17)
-
- Copper-catalyzed arene amination in pure aqueous ammonia
-
A simple protocol for copper-catalyzed arene amination using aqueous ammonia without any additional ligands and organic coordinating solvents has been developed. The reaction pathway via a Cu(i)/Cu(iii) mechanism is proposed based on the results of control experiments as well as DFT calculations.
- Takagi, Mio,Watanabe, Ayako,Murata, Shigeo,Takita, Ryo
-
supporting information
p. 1791 - 1795
(2019/02/20)
-
- Aromatic amine compound synthesis method
-
The invention discloses an aromatic amine compound synthesis method which is characterized in that the method is implemented according to any of two methods. The first method includes the steps: mixing an alkyl aromatic compound with a general formula (I) and a nitrogen-containing compound with a general formula (II); performing reaction on mixture under an oxidizing agent and an organic solvent to obtain an aromatic amine compound with a general formula (III). The second method includes the steps: mixing an aromatic alcohol derivative with a general formula (I') and the nitrogen-containing compound with the general formula (II); performing reaction on mixture under an acid additive and an organic solvent to prepare the aromatic amine compound with the general formula (III). According to the method, a lot of alkyl aromatic compounds or aromatic alcohol derivatives firstly serve as raw materials, and the raw materials are reacted to generate the aromatic amine compound without the action of metal catalysis. Compared with a traditional synthesis method, the synthesis method has the advantages that the method is high in yield and simple in condition, waste discharging amount is less,metal participation is omitted, a reaction device is simple, industrial production is easily achieved and the like. The method has a wide application prospect.
- -
-
Paragraph 0251-0253
(2019/01/23)
-
- A 2 - amino pyrazine derivatives of preparation method
-
The invention discloses a 2 - amino pyrazine derivatives of preparation method, comprises the following steps: C1: to 2 - cyano pyrazine is sequentially added in the sodium hypochlorite solution and alkali, then stirring, to obtain 2 - amino pyrazine; C2: step C1 of the obtained 2 - amino pyrazine join the brominating agent performing the bromination reaction, to obtain 2 - amino - 3, 5 - two bromine pyrrole qin; C3: step C2 of the obtained 2 - amino - 3, 5 - two bromine pyrrole qin with morpholine substitution reaction to obtain 2 - amino - 5 - bromo - 3 - morpholinyl pyrazine solution; C4: the 2 - amino - 5 - bromo - 3 - morpholinyl [...] is distilled out of the organic solvent, then wash the static separation, to obtain 2 - amino - 5 - bromo - 3 - morpholinyl pyrazine crude product. In order to 2 - cyano pyrazine as raw materials, is easy to prepare or procurement, after acid-base reaction, bromination reaction, the substitution reaction, distillation filtering and the like four-step operation preparation, preparation method is simple and convenient operation, the final preparation of the obtained 2 - amino pyrazine derivatives have high yield, is suitable for industrial production.
- -
-
Paragraph 0012; 0013; 0014
(2018/10/19)
-
- Transition-metal-free access to 2-aminopyridine derivatives from 2-fluoropyridine and acetamidine hydrochloride
-
Under catalyst-free conditions, an efficient method for the synthesis of 2-aminopyridine derivatives through the nucleophilic substitution and hydrolysis of 2-fluoropyridine and acetamidine hydrochloride has been developed. This amination uses inexpensive acetamidine hydrochloride as the ammonia source and has the advantages of a high yield, high chemoselectivity and wide substrate adaptability. The results suggest that other N-heterocycles containing fluorine substituents can also complete the reaction via these reaction conditions and yield the target products.
- Li, Yibiao,Huang, Shuo,Liao, Chunshu,Shao, Yan,Chen, Lu
-
supporting information
p. 7564 - 7567
(2018/11/02)
-
- Selective Cross-Coupling of (Hetero)aryl Halides with Ammonia to Produce Primary Arylamines using Pd-NHC Complexes
-
Herein we report the first example of (hetero)arylation of ammonia using a monoligated palladium-NHC complex. The new, rationally designed, precatalyst (DiMeIHeptCl)Pd(allyl)Cl featuring highly branched alkyl chains has been shown to be effective in selective aminations across a range of challenging substrates, including nitrogen-containing heterocycles and those featuring base-sensitive functionality. The less bulky Pd-PEPPSI-IPentCl precatalyst performs well for ortho-substituted aryl halides, giving monoarylated products in high yield with good selectivity.
- Lombardi, Christopher,Day, Jonathan,Chandrasoma, Nalin,Mitchell, David,Rodriguez, Michael J.,Farmer, Jennifer L.,Organ, Michael G.
-
supporting information
p. 251 - 254
(2017/04/26)
-
- A 2-amino-pyrazine derivatives method for the preparation of (by machine translation)
-
The invention relates to a 2-amino-pyrazine derivatives preparation method, which belongs to the technical field of organic synthesis. Using 2-cyano pyrazine as the raw material, by adding sodium hypochlorite solution and alkali, to obtain 2-amino-pyrazine, then bromination reaction to obtain 2-amino -3,5- [...], then to 2-amino -3,5- [...] as raw materials are respectively and morpholine, piperazine and pyrrolizinone the substitution reaction, respectively obtained 2-amino-5-bromo-3-morpholinyl-pyrazine, 2-amino-5-bromo-3-Piperazinylpyrazine and 2-amino-5-bromo-3-pyrrolidinyl pyrazine. This invention utilizes the 2-cyano pyrazine as the raw material, to preparation of different types of 2-amino-pyrazine derivatives, cheap and easily obtained raw materials, the operation is simple, high yield of target product. (by machine translation)
- -
-
Paragraph 0020; 0021; 0022
(2016/10/08)
-
- Peptide deformylase inhibitors
-
The present invention relates to a compound of Formula (I): or a pharmaceutically acceptable salt thereof, corresponding pharmaceutical compositions, compound preparation and treatment methods directed to bacterial infections and inhibition of bacterial peptide deformylase (PDF) activity.
- -
-
Page/Page column
(2014/12/09)
-
- Mild and highly selective palladium-catalyzed monoarylation of ammonia enabled by the use of bulky biarylphosphine ligands and palladacycle precatalysts
-
A method for the Pd-catalyzed arylation of ammonia with a wide range of aryl and heteroaryl halides, including challenging five-membered heterocyclic substrates, is described. Excellent selectivity for monoarylation of ammonia to primary arylamines was achieved under mild conditions or at rt by the use of bulky biarylphosphine ligands (L6, L7, and L4) as well as their corresponding aminobiphenyl palladacycle precatalysts (3a, 3b, and 3c). As this process requires neither the use of a glovebox nor high pressures of ammonia, it should be widely applicable.
- Cheung, Chi Wai,Surry, David S.,Buchwald, Stephen L.
-
supporting information
p. 3734 - 3737
(2013/08/23)
-
- PEPTIDE DEFORMYLASE INHIBITORS
-
The present invention relates to a compound of Formula (I): or a pharmaceutically acceptable salt thereof, corresponding pharmaceutical compositions, compound preparation and treatment methods directed to bacterial infections and inhi-bition of bacterial peptide deformylase (PDF) activity
- -
-
Page/Page column
(2014/02/15)
-
- 2,3-Diaminopyrazines as rho kinase inhibitors
-
Inhibition of rho kinase (ROCK) has been recognized as an important target for a number of diseases, including glaucoma. Herein we report SAR development around two hits from a kinase library that led to the discovery of the ROCK inhibitor compound 38. In vitro and in vivo analysis of this compound, including its effects in a monkey model of glaucoma will be discussed.
- Henderson, Alan J.,Hadden, Mark,Guo, Cheng,Douglas, Neema,Decornez, Helene,Hellberg, Mark R.,Rusinko, Andrew,McLaughlin, Marsha,Sharif, Naj,Drace, Colene,Patil, Raj
-
scheme or table
p. 1137 - 1140
(2010/06/15)
-
- A new class of pyrazolopyridine nucleus with fluorescent properties, obtained through either a radical or a Pd arylation pathway from N-azinylpyridinium N-aminides
-
(Chemical Equation Presented) The synthesis of dipyridopyrazole and pyridopyrazolopyrazine derivatives - both of which incorporate a 3-aryl moiety - can be achieved in moderate yields by intramolecular radical arylation of pyridinium N-aminides using tris(trimethylsilyl)silane and azobisisobutyronitrile. Improved results were obtained on using Pd direct arylation in conjunction with microwave irradiation. A preliminary study into the fluorescent properties of the target compounds is also reported.
- Abet, Valentina,Nunez, Araceli,Mendicuti, Francisco,Burgos, Carolina,Alvarez-Builla, Julio
-
scheme or table
p. 8800 - 8807
(2009/04/11)
-
- Efficient synthesis of a highly selective NPY-5 receptor antagonist: A drug candidate for the treatment of obesity
-
A concise and practical synthesis of highly selective NPY-5 receptor antagonist 1 is described. The animopyrazine intermediate 3 was synthesized via either monobromination of aminopyrazine or palladium-catalyzed regioselective debromination of dibromopyrazine followed by an efficient Suzuki-Miyaura coupling. For the preparation of the spirolactone piperidine 2, significantly improved yield was achieved by using a combination of n-BuMgCl and n-BuLi. This protocol also dramatically increased the thermal stability of the aryllithium intermediate and eliminated the requirement for costly cryogenic conditions. The union of the spirolactone piperidine 2 and aminopyrazine 3 via a carbonyl group was accomplished using phenyl chloroformate delivering the target molecule in high yield.
- Itoh, Takahiro,Kato, Shinji,Nonoyama, Nobuaki,Wada, Toshihiro,Maeda, Kenji,Mase, Toshiaki,Zhao, Matthew M.,Song, Jake Z.,Tschaen, David M.,McNamara, James M.
-
p. 822 - 828
(2012/12/22)
-
- SUBSTITUTED ARYLPYRAZINES
-
Arylpyrazine compounds are provided, including arylpyrazines that can bind with high affinity and high selectivity to CRF1 receptors, including human CRF1 receptors. The invention thus includes methods for treatment of disorders and diseases associated with CRF1 receptors, including CNS-related disorders and diseases, particularly affective disorders and diseases, and acute and chronic neurological disorders and diseases.
- -
-
-
- N-azinylpyridinium N-aminides: An approach to pyrazolopyridines via an intramolecular radical pathway
-
Intramolecular radical arylation, under thermal conditions, to a π-deficient pyridinium, linked to a π-excessive 2-azinyliminopyridine moiety is described. The method allows a new entry to pyrazolo[1,5-a]pyridine nucleus.
- Nu?ez, Araceli,García de Viedma, Aránzazu,Martínez-Barrasa, Valentín,Burgos, Carolina,Alvarez-Builla, Julio
-
p. 1093 - 1096
(2007/10/03)
-
- Solid phase synthesis of aryl and heteroaryl amines using the Curtius rearrangement
-
An efficient method for the solid phase synthesis of secondary aryl amines and heteroaryl amines was developed. The key step was the formation of aryl or heteroaryl carbamates using the Curtius rearrangement of aryl carboxylic acids with Wang resin as a trapping hydroxyl group. N-alkylation reactions of resin-bound carbamates under the Mitsunobu condition or using sodium hydride gave secondary aryl or heteroaryl amines in good yields. The developed method can be applied in the preparation of libraries containing aryl and heteroaryl amine structures as a pharmacophore.
- Sunami, Satoshi,Sagara, Takeshi,Ohkubo, Mitsuru,Morishima, Hajime
-
p. 1721 - 1724
(2007/10/03)
-
- Cyanoamino Compounds in Synthesis Syntheses of Some Heterocycles
-
Transformations of some heterocyclic cyanoamino compounds leading to various heterocyclic systems are described. s-Triazolo(1,5-a)azines are obtained either in a direct synthetic approach or via the substituted aminotetrazoles, substituted 3-amino-5-oxo-1,2,4-oxadiazolines, and from N-ethoxycarbonyl N'-heteroaryl thioureas or N-heteroaryl N'-hydroxyguanidine.The cyanoamino group reacts also with o-difunctional benzenes to give the corresponding substituted derivatives of benzimidazole, benzoxazole or benzothiazole. - Keywords: Cyclization with N-N bond formation; Heterocyclic compounds; Rearrangements
- Vercek, Bojan,Ogorevc, Bozidar,,Stanovnik, Branko,Tisler, Miha
-
p. 789 - 798
(2007/10/02)
-
- ACIDIFYING EFFECTS OF AZA GROUPS IN THE NH ACIDITY OF AMINOAZINES AND THE CH ACIDITY OF ACETYLAZINES
-
The pK values for a series of aminoazines and acetylazines containing one, two, or three aza groups in the ring were determined in dimethyl sulfoxide.There is a good linear correlation between pK values of the investigated NH and CH acids.The acidifying effects (ΔpK) of the aza groups at positions 2, 3, or 4 in relation to the side chain were determined and had values of 3.1, 2.4, and 4.5 logarithmic units in the aminoazines and 3.5, 2.9 and 4.8 logarithmic units respectively in the acetylazines.Except in the case of two ortho-located aza groups the effects are additive.Compared with dimethyl sulfoxide water has a differentiating effect on the acidity of the aminoazines, and this is explained by the formation of hydrogen bonds between the molecules of the proton-donating solvent and the aza groups of the anions of the aminoazines.
- Terekhova, M. I.,Petrov, E. S.,Mikhaleva, M. A.,Shkurko, O. P.,Mamaev, V. P.,Shatenshtein, A. I.
-
-
- On the Amination of Azaheterocycles. A New Procedure for the Introduction of an Amino Group
-
A new method of amination of diazines and triazines, using potassium amide, liquid ammonia and potassium permanganate, has been described.
- Hara, Hiroshi,Plas, Henk C. van der
-
p. 1285 - 1287
(2007/10/02)
-