A. V. Aksenov

Metal-free transannulation reaction of indoles with nitrostyrenes: a simple practical synthesis of 3-substituted 2-quinolones.

3-Substituted 2-quinolones are obtained via a novel, metal-free transannulation reaction of 2-substituted indoles with 2-nitroalkenes in polyphosphoric acid. The reaction can be used in conjunction with the Fisher indole synthesis offering a practical three-component heteroannulation methodology to produce 2-quinolones from arylhydrazines, 2-nitroalkenes and acetophenone.

Metal-free ring expansion of indoles with nitroalkenes: a simple, modular approach to 3-substituted 2-quinolones

3-Substituted 2-quinolones are obtained via a novel metal-free transannulation reaction of 2-nitroolefins with 2-substituted indoles in polyphosphoric acid. This acid-mediated cascade transformation operates via the ANRORC (Addition of Nucleophile, Ring Opening, and Ring Closure) mechanism and can be used in combination with the Fisher indole synthesis to offer a practical three-component hetero-annulation approach to 2-quinolones from arylhydrazines, 2-nitroalkenes, and acetophenone. An alternative entry to this chemistry employing the alkylation of electron-rich arenes and hetarenes with 1-(2-indolyl)-2-nitroalkene has also been demonstrated.

Synthesis of N-Phenyl-1,5,7-Triazacyclopenta[cd]- Phenalenes by the Reaction of 1H-Perimidine Carbonyl Derivatives with Nitrobenzene

A [cd]-annelated indole structural framework is often met in natural and synthetic compounds which show a variety of biological activity [1-3]. In addition, as low toxicity analogs of acenapthenes and benzopyrenes, such polyheterocyclic molecules may in the future replace these widely used photochemical probes [4] and this makes them more attractive for medical applications. Similar structures can be used in nanotechnology for modeling the reactivity of azafullerenes [5] and atom-modified nanotubes [6]. We have previously reported development of a method for the direct peri annelation of a pyrrole ring to 1H-perimidine derivatives containing a functional group at position 6(7). Either 1,3,5-triazines in polyphosphoric acid (PPA) [7] or a combination of 1,3,5-triazines with sodium azide in PPA [8] have been used as reagents. The unsubstituted 1H-1,5,7-triazacyclopenta[cd]phenalene and derivatives of this heterocyclic

Activity of 2-aryl-2-(3-indolyl)acetohydroxamates against drug-resistant cancer cells.

Many types of tumor, including glioma, melanoma, non-small cell lung, esophageal, and head and neck cancer, among others, are intrinsically resistant to apoptosis induction and poorly responsive to current therapies with proapoptotic agents. In addition, tumors often develop multidrug resistance based on the cellular efflux of chemotherapeutic agents. Thus, novel anticancer agents capable of overcoming these intrinsic or developed tumor resistance mechanisms are urgently needed. We describe a series of 2-aryl-2-(3-indolyl)acetohydroxamic acids that are active against apoptosis- and multidrug-resistant cancer cells as well as glioblastoma neurosphere stemlike cell cultures derived from patients. Thus, the described compounds serve as a novel chemical scaffold for the development of potentially highly effective clinical cancer drugs.

One-pot synthesis of benzoxazoles via the metal-free ortho-C–H functionalization of phenols with nitroalkanes

PPA-activated nitroalkanes are employed in the design of a one-pot cascade transformation involving metal-free and oxidant-free direct ortho-C–H functionalization, followed by Beckman rearrangement and intramolecular cyclocondensation to produce benzoxazoles and benzobisoxazoles directly from easily available phenols.

Direct metal-free synthesis of diarylamines from 2-nitropropane via the twofold C–H functionalization of arenes

Synthesis of symmetric diarylamines via a twofold intermolecular electrophilic C–H functionalization of electron-rich arenes by umpolung-activated nitroalkane in polyphosphoric acid is demonstrated.

Nitromethane in Polyphosphoric Acid—A New Reagent for Carboxyamidation and Carboxylation of Activated Aromatic Compounds

Abstract A new method of carboxyamidation of aromatic compounds based on their reaction with nitromethane in polyphosphoric acid has been developed. Upon the hydrolysis of benzamides during the reaction mixture workup, the corresponding benzoic acids can be obtained. GRAPHICAL ABSTRACT

Organic chemistry. History and mutual relations of universities of Russia

The review describes the history of development of organic chemistry in higher schools of Russia over a period of 170 years, since the emergence of organic chemistry in our country till now.

Heterocyclic Analogs of Pleiadiene: LXXIV. peri-Cyclizations in the Perimidine Series. Synthesis of 1,3-Diazapyrene Derivatives

Reactions of perimidines and perimidin-2-ones with α,β-unsaturated carbonyl compounds gave various 1,3-diazapyrene derivatives. Acylation of 1-methylperimidine, perimidin-2-one, and 1-methylperi-midin-2-one with cinnamoyl chloride in the presence of AlBr3 is accompanied by peri-fusion at the 6,7-position and dearylation of the intermediate product. Under analogous conditions, 1,3-dimethyl-2,3-dihydroperimidine gave rise to 6-cinnamoyl-1,3-dimethyl-2,3-dihydroperimidine. Reactions of perimidin-2-ones with 1,3-di-phenyl-2-propenone in polyphosphoric acid resulted in peri-fusion at the 6,7-position, and with acetylacetone, at the 1,9-position.

One-Pot, Three-Component Assembly of Indoloquinolines: Total Synthesis of Isocryptolepine

Indolo[3,2-c]quinolones have been efficiently synthesized via an acid-mediated, one-pot, three-component condensation of arylhydrazines, o-aminoacetophenones, and triazines or nitriles. The synthetic application of this method is showcased by the concise synthesis of isocryptolepine alkaloid and a series of its synthetic analogues with demonstrated cancer cell antiproliferative activities.