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M P Kaushik - One of the best experts on this subject based on the ideXlab platform.
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n n dichlorobis 2 4 6 trichlorophenyl urea cc 2 as a new reagent for the synthesis of pyrimidone and Pyrimidine derivatives via biginelli reaction
Tetrahedron Letters, 2011Co-Authors: B. N. Acharya, Sanjeev K Verma, M P KaushikAbstract:A simple and efficient method for the synthesis of 3,4-dihydropyrimidin-2-(1H)one and benzo[4,5]imidazo/thioazo[1,2-a]Pyrimidine derivatives has been described using N,N′-dichlorobis(2,4,6-trichlorophenyl)urea (CC-2) as a new reagent. This method is found to be efficient and convenient for the synthesis of pyrimidone and Pyrimidine derivatives.
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N,N′-Dichlorobis(2,4,6-trichlorophenyl)urea (CC-2) as a new reagent for the synthesis of pyrimidone and Pyrimidine derivatives via Biginelli reaction
Tetrahedron Letters, 2011Co-Authors: B. N. Acharya, Sanjeev K Verma, M P KaushikAbstract:A simple and efficient method for the synthesis of 3,4-dihydropyrimidin-2-(1H)one and benzo[4,5]imidazo/thioazo[1,2-a]Pyrimidine derivatives has been described using N,N′-dichlorobis(2,4,6-trichlorophenyl)urea (CC-2) as a new reagent. This method is found to be efficient and convenient for the synthesis of pyrimidone and Pyrimidine derivatives.
B. N. Acharya - One of the best experts on this subject based on the ideXlab platform.
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n n dichlorobis 2 4 6 trichlorophenyl urea cc 2 as a new reagent for the synthesis of pyrimidone and Pyrimidine derivatives via biginelli reaction
Tetrahedron Letters, 2011Co-Authors: B. N. Acharya, Sanjeev K Verma, M P KaushikAbstract:A simple and efficient method for the synthesis of 3,4-dihydropyrimidin-2-(1H)one and benzo[4,5]imidazo/thioazo[1,2-a]Pyrimidine derivatives has been described using N,N′-dichlorobis(2,4,6-trichlorophenyl)urea (CC-2) as a new reagent. This method is found to be efficient and convenient for the synthesis of pyrimidone and Pyrimidine derivatives.
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N,N′-Dichlorobis(2,4,6-trichlorophenyl)urea (CC-2) as a new reagent for the synthesis of pyrimidone and Pyrimidine derivatives via Biginelli reaction
Tetrahedron Letters, 2011Co-Authors: B. N. Acharya, Sanjeev K Verma, M P KaushikAbstract:A simple and efficient method for the synthesis of 3,4-dihydropyrimidin-2-(1H)one and benzo[4,5]imidazo/thioazo[1,2-a]Pyrimidine derivatives has been described using N,N′-dichlorobis(2,4,6-trichlorophenyl)urea (CC-2) as a new reagent. This method is found to be efficient and convenient for the synthesis of pyrimidone and Pyrimidine derivatives.
Sanjeev K Verma - One of the best experts on this subject based on the ideXlab platform.
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n n dichlorobis 2 4 6 trichlorophenyl urea cc 2 as a new reagent for the synthesis of pyrimidone and Pyrimidine derivatives via biginelli reaction
Tetrahedron Letters, 2011Co-Authors: B. N. Acharya, Sanjeev K Verma, M P KaushikAbstract:A simple and efficient method for the synthesis of 3,4-dihydropyrimidin-2-(1H)one and benzo[4,5]imidazo/thioazo[1,2-a]Pyrimidine derivatives has been described using N,N′-dichlorobis(2,4,6-trichlorophenyl)urea (CC-2) as a new reagent. This method is found to be efficient and convenient for the synthesis of pyrimidone and Pyrimidine derivatives.
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N,N′-Dichlorobis(2,4,6-trichlorophenyl)urea (CC-2) as a new reagent for the synthesis of pyrimidone and Pyrimidine derivatives via Biginelli reaction
Tetrahedron Letters, 2011Co-Authors: B. N. Acharya, Sanjeev K Verma, M P KaushikAbstract:A simple and efficient method for the synthesis of 3,4-dihydropyrimidin-2-(1H)one and benzo[4,5]imidazo/thioazo[1,2-a]Pyrimidine derivatives has been described using N,N′-dichlorobis(2,4,6-trichlorophenyl)urea (CC-2) as a new reagent. This method is found to be efficient and convenient for the synthesis of pyrimidone and Pyrimidine derivatives.
Youhong Hu - One of the best experts on this subject based on the ideXlab platform.
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microwave assisted tandem heck sonogashira reactions of n n di boc protected 6 amino 5 iodo 2 methyl pyrimidin 4 ol in an efficient approach to functionalized pyrido 2 3 d Pyrimidines
Organic Letters, 2014Co-Authors: Zi Wang, Linhua Song, Youhong HuAbstract:A microwave assisted tandem Heck–Sonogashira cross-coupling reaction between 6-N,N-di-Boc-amino-5-iodo-2-methyl pyrimidin-4-ol and various aryl alkynyl substrates has been developed. This process generates novel 5-enynyl substituted Pyrimidines, which can be transformed to novel functionalized pyrido[2,3-d]Pyrimidines by way of a silver catalyzed cyclization reaction.
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three component one pot synthesis of 2 4 5 substituted Pyrimidines library for screening against human hepatocellular carcinoma bel 7402 cells
ACS Combinatorial Science, 2007Co-Authors: Shukun Li, Youhong HuAbstract:ReceiVed September 8, 2006 Pyrimidine is found widely as a core structure in a large variety of compounds that exhibit important biological activity.1 It is convenient to synthesize substituted Pyrimidines by reaction of amidines or guanidine with R,!unsaturated ketones, !-diketones, !-alkoxyand !-aminovinyl ketones, and N-aryl acetyleneic imines.2 The use of combinatorial approaches to the high-throughput synthesis of this druglike scaffold would be a powerful advance in helping to speed up drug discovery. Recently, Nie et al. have reported a new method for the preparation of a 2,4,6substituted Pyrimidines library using a microwave-assisted reaction of 2!-hydroxychalcones with amidines or guanidine.3 To the best of our knowledge, no method was explored to generate the 2,4,5-substitued Pyrimidines for combinatorial synthesis. Here, we report (1) a combinatorial synthesis of a 2,4,5-substituted Pyrimidine library using a sequential threecomponent, one-pot reaction and (2) its antitumor activities. Chromone as a 1,3-diketone equivalent can be condensed with amidine to form o-hydroxyphenyl Pyrimidine.5 Since substitution of Pyrimidine at the 4-position will block Suzuki coupling of a 5-iodo-4-substituted Pyrimidine, we thus designed a one-pot process to form 2,4,5-substitued Pyrimidines by Suzuki coupling6 that applies diversified commercial available boronic acids to the chromone core, followed by condensation with a variety of amidines (Scheme 1). According to our reported method,4 a mixture of iodochromone (1.2 mmol) and aryl boronic acids (1.1 equiv) in the presence of 2% Pd(PPh3)4 and 2.0 equiv K2CO3 in 5 mL THF-H2O (4:1) was refluxed overnight and then split into six portions, to which was added 1.5 equiv of amidines f-k (0.3 mmol) and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU, 0.3 mmol or 0.6 mmol) for each portion. The mixture was stirred at 50-60 °C for about 10 h, and the corresponding products were obtained by flash chromatography. Using five boronic acids and six amidines (Table 1), we successfully synthesized a small quantity of a Pyrimidine library including 30 diversified compounds. The electronic variations on both the aryl group of the boronic acid and the substitution of amidine gave the desired product in moderate to good yield (Table 2). The compounds were assayed for the inhibition of human hepatocellular carcinoma cell line BEL-7402 (Table 2). Two compounds, ak and dh, exhibited a high degree of inhibition, more than 80% against BEL-7402 cell growth at 15 μM, with an IC50 value of 1.02 and 5.08 μM, respectively. In the process of preparation of a large amount of ak, we tested Felpin’s reported method,7 which applied catalytic 10% Pd/C as an inexpensive catalyst for Suzuki coupling in aqueous acetonitrile, followed by condensation with acetamidine in DMF separately. The compound ak was obtained in 77% yield over two steps. (Scheme 2). According to the bioassay result, we then kept the building blocks a, k and d, h to synthesize several derivatives of ak * To whom correspondence should be addressed. Phone/Fax: 86-02150805896. E-mail: yhhu@mail.shcnc.ac.cn. Scheme 1. Synthesis of Diversified 2,4,5-Substituted Pyrimidines via Suzuki Coupling and Condensation
Nikita Tolstoluzhsky - One of the best experts on this subject based on the ideXlab platform.
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efficient synthesis of uracil derived hexa and tetrahydropyrido 2 3 d Pyrimidines
European Journal of Organic Chemistry, 2013Co-Authors: Nikita Tolstoluzhsky, N. N. Gorobets, Pavlo Nikolaienko, Erik V. Van Der Eycken, Nadezhda N. KolosAbstract:A reaction of 6-amino-1,3-dimethyluracil with 3-(hetero)aroylacrylic acids and their methyl esters leads to hexahydropyrido[2,3-d]Pyrimidine-5-carboxylic acids or the corresponding methyl esters in high to excellent yields. One-pot oxidation of the acid derivatives with CAN is accompanied by decarboxylation to give tetrahydropyrido[2,3-d]Pyrimidines, while oxidation with bromine resulted in the formation of tetrahydropyrido[2,3-d]Pyrimidine-5-carboxylic acids. The aromatization of methyl hexahydropyrido[2,3-d]Pyrimidine-5-carboxylates was achieved by K2CO3-mediated air oxidation under ambient conditions.
