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• 119-52-8 4,4'-dimethoxybenzoin 
• 77287-34-4 formamide 
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• 5720-07-0 4-methoxyphenylboronic acid 
• 1226-42-2 1,2-bis(4-methoxyphenyl)-1,2-ethanedione 
• 58520-45-9 (1R,2S)/(1S,2R)-1,2-diamino-1,2-bis(4-methoxyphenyl)ethane 
• 92901-78-5 1-amino-1-(p-methoxyphenyl)-4'-methoxyacetophenone 

Relevant academic research and scientific papers

Tetraphenylpyrazine-based AIEgens: Facile preparation and tunable light emission

Research on aggregation-induced emission (AIE) has been a hot topic. Due to enthusiastic efforts by many researchers, hundreds of AIE luminogens (AIEgens) have been generated which were mainly based on archetypal silole, tetraphenylethene, distyrylanthrac

Phosphine Supported Ruthenium Nanoparticle Catalyzed Synthesis of Substituted Pyrazines and Imidazoles from α-Diketones

A new methodology has been developed for the synthesis of highly substituted nitrogen heterocycles such as pyrazines and imidazoles starting from α-diketones using phosphine supported ruthenium nanoparticles (RuNPs) as catalysts. Ruthenium nanoparticles Ru1-Ru4 supported with different phosphines such as dbdocphos, dppp, DPEphos, and Xantphos are screened, of which Ru1 and Ru4 are found to be the most active. Interestingly, aryl-substituted and alkyl-substituted α-diketones produced different products: namely, pyrazine and imidazoles, respectively. This reaction methodology has been applied to the synthesis of a key intermediate (2m) of the marine cytotoxic natural product Dragmacidin B and an estrogen receptor (2l). This work represents the first examples of pyrazines prepared by RuNPs.

An Improved Synthesis of Multi-Substituted Pyrazines under Catalyst- and Solvent-Free Conditions

A one-pot pseudo four-component reaction between a variety of 2-hydroxy-1,2-diarylethanone derivatives and ammonium acetate or amines has been developed to synthesize substituted pyrazines under catalyst-free and solvent-free conditions. This procedure provides a synthetic method to access pyrazine derivatives in excellent yields under green conditions.

SnCl2·2H2O-Catalyzed Solvent-Free Synthesis of α-Amino Ketones and Tetrasubstituted Pyrazines

Solvent-free reaction of various anilines with α-hydroxy ketones catalyzed by SnCl2·2H2O provides α-amino ketones in excellent yields. While a similar reaction with aliphatic amines is applicable for the synthesis of substituted pyrazines, SnCl2·2H2O permits versatility in the solvent-free reaction of α-hydroxy ketones with ammonium acetate to give the corresponding substituted pyrazines in good to excellent yields.

Synthesis of tetraaryl- and tetraalkenylpyrazines by Suzuki-Miyaura reactions of tetrachloropyrazine

The first Suzuki-Miyaura reactions of tetrachloropyrazine allowed for a new and convenient approach to synthesize a variety of tetraarylpyrazines and tetraalkenylpyrazines, which were isolated in good to excellent yields. The products show strong fluoresc

Estrogenic diazenes: Heterocyclic non-steroidal estrogens of unusual structure with selectivity for estrogen receptor subtypes

Estrogens regulate many biological functions, often acting in a tissue-selective manner. Their tissue-selective action is believed to involve differential estrogen action through the two estrogen receptor (ER) subtypes, ERα and ERβ, as well as differential interaction of the ligand-receptor complexes with promoters and coregulator proteins. In the latter case, selectivity is based on the induction of specific conformations of the ligand-ER complex, conformations that are influenced by the structure of the ligand. Estrogen pharmaceuticals having an ideal balance of tissue-selective activity are being sought for menopausal hormone replacement, breast cancer prevention and therapy, and other actions. To expand on the structural diversity of ER ligands that might show such tissue selectivity, we have prepared a series of diazenes (pyrazines, pyrimidines, and pyridazines) substituted with two to four aryl groups and various short-chain aliphatic substituents. All of the pyrazine and pyrimidines bind to ER, some with high affinity and with a considerable degree of preferential binding to either ERα or ERβ. One pyrimidine and one pyrazine have ERα affinity preferences as high as 23 and 9, respectively, and one pyrimidine has an ERβ affinity preference of 8. The pyridazines, by contrast, are quite polar and have only very low binding affinity for the ER. In cell-based transcription assays, several of the pyrimidines and a pyrazine were found to be considerably more agonistic on ERα than on ERβ. Because these triaryl diazenes have the largest volumes among the ER ligands so far investigated, their high affinity demonstrates the flexibility of the ligand binding pocket of the ERs and its tolerance for large substituents. Thus, these novel heterocyclic ligands expand the repertoire of chemical structures that bind to the estrogen receptor, and they could prove to be useful in elucidating the biological behavior of the two ER subtypes and in forming the basis for new estrogen pharmaceuticals having desirable tissue selectivity.

Photochemistry of Vinyl Halides. Heterocycles from Reaction of Photogenerated Vinyl Cations with Azide Anion

Irradiation of 1,2,2-tris(p-methoxyphenyl)vinyl bromide (1a-Br) and tetrabutylammonium azide in acetonitrile afforded 1,1,3,4,6,6-hexakis(p-methoxyphenyl)-2,5-diaza-1,3,5-hexatriene (2a).Formation of 2a suggests the presence of azirine 3a as a reactive intermediate and a route to synthesis of heterocycles in combination with azirine photochemistry.Irradiation of α-arylvinyl halides 1 and tetrabutylammonium azide in acetonitrile in the presence of dimethyl fumarate gave 1-pyrrolidine derivatives 5.When the irradiation was performed in acetone, oxazoline derivatives 6 were obtained.The reaction of vinyl halides 1 with azide anion took place succesfully even in a two phase system, i.e., water-methylene chloride-tetrabutylammonium halide as a phase-transfer catalyst.In addition, photolysis of 2,2-bis(p-methoxyphenyl)-1-phenylvinyl bromide (1f-Br) in a two-phase system led to the formation of the β-aryl rearranged pyrrolines 5f.This results indicates strong evidence for the intervention of vinyl cations in the photochemical reaction of the vinyl halide 1 and azide anion.The mechanistic points on the photochemical substitution and the scope and limitation of the reaction are discussed.