3-Formylchromones as diverse building blocks in heterocycles synthesis

This review covers the chemical reactivity of 3-formylchromones towards condensation reactions with a variety of carbon and nitrogen nucleophiles. Some chromone derivatives linked a variety of heterocyclic systems were prepared from the direct condensation of 3-formylchromones with heterocyclic compounds containing active methylene groups. A diverse number of fused heterocyclic systems were prepared from the reaction of 3-formylchromones with some bifunctional nucleophiles, these reactions mainly proceed via condensation with the aldehydic function followed by nucleophilic attack at C-2 position of the chromone moiety

An efficient synthesis of some new isolated and fused 2-oxo-2H-chromene derivatives as antimicrobial and antitumor agents

An efficient synthesis of the biologically active novel systems derived from the reaction of 4-methyl-2-oxo-2H-chromene-3-carbonitrile (1) with sodium hydroxide and/or DMF-DMA and cyclocondensation reactions of 4-[(E)-2-(dimethylamino)ethenyl]-2-oxo-2H-chromene-3-carbonitrile (5) with nitrogen nucleophilic reagents afforded the corresponding 4-iminochromeno[3,4-c]pyridine derivatives (6-14). The structures of the prepared compounds have been proved by elemental analysis, IR, 1H  and 13C NMR and mass spectra. Significant antitumor activities in planta were observed for some of the prepared compounds

Tigran Mansuryan. Análisis y catalogación de la obra musical

Esta tesis doctoral trata sobre la figura del compositor armenio Tigran Mansuryan. El método de investigación desarrollado ha sido cualitativo siendo el propio artista Mansuryan quien a través de las entrevistas e investigaciones llevadas a cabo sobre la Historia de Armenia, cultural y política, ha descrito de una manera clara y concisa su pensamiento intelectual mediante las diferentes creaciones musicales a lo largo de su vida, destacando una de sus composiciones más significativas de su obra: el Réquiem. Por otro lado, hemos podido visualizar una riqueza cultural que, de la propia mano de nuestro compositor nos amplía el significado y profundidad de su música. En este sentido, Mansuryan nos ha guiado por un camino de excepcional belleza artística donde la música actúa como un verdadero enlace de un país, Armenia, cuyo folklore, tradiciones y lenguaje son elevados por la propia música de Mansuryan, que se fundamenta en estos tres aspectos principales mencionados. Para concluir, hemos corroborado que Mansuryan se declara ser un continuador del legado de Komitas influenciado por Debussy y Boulez, formando parte de la música de vanguardia europea. En todo momento, ambos creadores, Komitas y Mansuryan, han fundamentado su música en las tradiciones armenias y vivencias de su tiempo. Mansuryan rinde un homenaje en su Réquiem, estrenado en el Prinzegententheater de Berlin el 19 de noviembre del año 2011 a las víctimas del genocidio de 1915.This doctoral thesis deals with the figure of the Armenian composer Tigran Mansuryan. The research method we have used is based on interviews and research carried out on Armenian history, culture and politics. In a clear and concise manner, they describe Mansuryan's intellectual thought, which he showed through different musical creations throughout his life. We highlight one of the most significant compositions of his work: the Requiem. On the other hand, we could visualize the cultural wealth of the composer's own hand and we extend the meaning and depth of his music. In this sense, Mansuryan has led us down a path of exceptional artistic beauty where his music acts as a true bond of a country, Armenia, whose folklore, traditions and language are elevated by the Mansuryan's music. To conclude, we have confirmed that Mansuryan declared to be a continuation of the legacy of Komitas influenced by Debussy and Boulez, as part of the European avant--‐garde music. At all times, both creators and Mansuryan Komitas, have based their music on the Armenian traditions and experiences of his time. Mansuryan pays tribute in his Requiem to the victims of the 1915 genocide. It premiered at the Berlin Prinzegententheater on 19 November 2011

Recommendations on Diagnostics of Support Condition of High-Speed Spindle Units

In the course of the study, amplitude-frequency characteristics of the responses of vibrational acceleration of the spindle unit were obtained experimentally with a short-term impact of a force directly on its spindle. By analyzing the frequency composition of amplitude spectra, the peaks of natural frequencies of the spindle unit were determined at various values of the preload, and, accordingly, the operating modes of the spindle unit were selected, which would reduce its vibration activity and increase processing accuracy

Effect of Microwave Irradiation on the Condensation of 6-Substituted 3-Formylchromones with Some Five-membered Heterocyclic Compounds

Different types of 3-substituted 4H-4-oxobenzopyrans were prepared by microwave irradiation as well as by a classical method. The beneficial effect of microwave irradiation on the aldol condensation of 3-formylchromones with 2-imino-1-methylimidazolidine-4-one (creatinine), 2-thioxoimidazolidine-4-one (thiohydantoin) and 2-ethyl-2-thioxothiazolidin-4-one (3-ethylrhodanine) in different reaction media is described. Our results show that the effect of microwave irradiation on the reactions studied was a shortening of the reaction times and a smooth increase in the yields. The subsequent reactions of the product with some nucleophiles are discussed. The structure of the products was proven by elemental analysis, IR and NMR spectra