Catalyst free conjugate addition of indoles and pyrroles to nitro alkenes under solvent free condition (SFC): an effective greener route to access 3-(2-nitro-1-phenylethyl)-1H-indole and 2-(2-nitro-1-phenylethyl)-1H-pyrrole derivatives

Green synthesis, molecular docking and anticancer activity of novel 1,4-dihydropyridine-3,5-Dicarbohydrazones under grind-stone chemistry

“…Catalyst-and solvent-free synthetic methods are important for both chemical industry and laboratory synthesis because of lower costs, reduced pollution, ease of purification, and mild conditions. Procedures without catalysts and solvents have been advised for cleaner and greener syntheses (1)(2)(3)(4). The grinding technique, as solvent-free reactions, has been widely used in organic synthesis (5)(6)(7).…”

The Trifluoromethyl Group as a Bioisosteric Replacement of the Aliphatic Nitro Group in CB1 Receptor Positive Allosteric Modulators

“…The reaction of an indole with nitrostyrene has been widely reported in the literature and there are a considerable range of methods available for this simple 1,4-conjugate addition reaction. [17][18][19][20][21][22][23][24] There is literature precedent for the nitro group to be replaced with a carboxylic acid in this series of compounds, which is achieved by initial reaction of an indole with the highlyelectron deficient diethylbenzylidene malonate. 21,22 The limited similarity of nitro group binding to carboxylic acid binding, in spite of the near perfect isosterism, has been discussed by Kelly and Kim.…”

“…Because of this strong electron-withdrawing nature, the presence of a nitro group also facilitates many chemical reactions; thus, it is often found in screening collections (including the collection from which AZ-4 was originally identified). The reaction of an indole with nitrostyrene has been widely reported in the literature, and there are a considerable range of methods available for this simple 1,4-conjugate addition reaction. − There are literature precedents for the nitro group to be replaced with a carboxylic acid in this series of compounds, which is achieved by initial reaction of an indole with the highly electron-deficient diethylbenzylidene malonate. , The limited similarity of nitro group binding to carboxylic acid binding in spite of the near-perfect isosterism has been discussed by Kelly and Kim . A small range of derivatives can be accessed from the carboxylic acid (for example, CH 2 OH, CO 2 H, CO 2 Et, CONHNH 2 , CONH 2 , and CONHMe, Figure ; see the Supporting Information); however, these were inactive as CB 1 PAMs.…”

An Efficient and Versatile Method for Synthesis of 1,4-Dihydropyridines at Mild Reaction Conditions

“…In the context of green chemistry, the development of new methodologies in organic synthesis involving multicomponent reactions (MCRs) have become a significant area of research in organic chemistry and so practical procedures in the absence of solvents and catalysts have been adopted for accomplishment of greener and cleaner synthesis [1][2][3][4] . As the typical representative of solvent-free reactions, the grinding technique has been widely used in organic synthesis [5][6][7] . Among heterocyclic compounds containing six membered ring, important constituents that are usually found in biologically active natural products and medicinal compounds are 1,4-dihydropyridines [8][9][10] .…”