Showing papers by "Murlidhar S. Shingare published in 2003"
TL;DR: The condensation of 1,3-diphenyl-1H-pyrazole-3-carbaldehydes with 3-methyl-1-phenylpyrazolin-5-(4H-)-one in an ionic liquid (ethylammonium nitrate) afforded 3methyl-4-[(1,3diphensyl- 1H--pyrazolo-4-yl)methylene]-1,phenyl pyrazolin]-5-( 4H)-ones in an excellent yield at room temperature as discussed by the authors.
9 citations
Journal Article•
TL;DR: A newer series of 13 compounds viz. 2-aryl-3,4-dihydrobenzopyrano [3, 4-d]-1, 2, 3-selenadiazoles 3 and 3-thiadiazole 4 have been synthesized from their chroman-4-one precursors.
Abstract: A newer series of 13 compounds viz. 2-aryl-3,4-dihydrobenzopyrano [3, 4-d]-1, 2, 3-selenadiazoles 3 and 2-aryl-3,4-dihydrobenzopyrano [3,4-d]-1, 2, 3-thiadiazoles 4 have been synthesized from their chroman-4-one precursors.
3 citations
TL;DR: The condensation reaction of 3-formylchromones with 3-carboxaldehydes with hydrazine, hydroxyl amines and guanidine has been extensively studied as mentioned in this paper.
Abstract: Condensation reactions of 3-formylchromones, (4oxo4H[I ]benzopyran3-carboxaldehydes) with compounds containing active methylene group were extensively studied 1-7. Such types of condensations are generally achieved by using either acid or base catalyst. The condensation reaction of 4-oxo-4H-[ 1]benzopyran-3-carboxaldehydes with hydrazine, monosubstituted hydrazine, amidines, hydroxyl amines and guanidine have been extensively studied1I •
2 citations
TL;DR: In this article, it was shown that chroman-4-one-one can be used to synthesize 1,2,3-selenadiazoles and thiadiazole rings.
Abstract: Substituted chroman-4-ones, a class of oxygen heterocycles are common among the natural products and are extensively used as synthetic intermediates I. They have been used to prepare various fused heterocyclic ring systems and have been used for a wide range of pharmacological activitl. Some chroman-4ones with medical use are khellin , a coronary vasodilator,4, chroman-4-one-2-carboxylic acids, a spasmolytic agent and disodium chromoglycate, and an antiallergenic drug 5. On the other hand, it is well known that a number of heterocyclic compounds containing nitrogen and sulfur exhibit a wide variety of biological activities. However, reports about selenium containing heterocycles are relatively Iess-, although some of them are used as chemotherapeutic agents; also some 1, 3, 4 and 1, 2, 3selenalthiadiazoles were found to possess significant antibacterial and antiviral activities. lo . The fused ring systems of chroman-4-ones are found to posses enhanced biological activities and the synthesis of the title heterocycles (selenadiazoles and thiadiazoles) is of growing interest, say, 1,2,3-selenal thiadiazole rings, worked out by Bhaskar Reddy el t ll -19 f db· a . use to car ocyclJc/heterocychc rings. Therefore, as a part of continuation of our work2o on chromone nucleus, it was thought to synthesize 1,2,3 selenalthiadiazoles fused to chroman-4-one.s.
TL;DR: The condensation of 1,3-diphenyl-1H-pyrazole-3-carbaldehydes with 3-methyl-1-phenylpyrazolin-5-(4H-)-one in an ionic liquid (ethylammonium nitrate) afforded 3methyl-4-[(1,3diphensyl- 1H--pyrazolo-4-yl)methylene]-1,phenyl pyrazolin]-5-( 4H)-ones in an excellent yield at room temperature.
Abstract: The condensation of 1,3-diphenyl-1H-pyrazole-3-carbaldehydes with 3-methyl-1-phenylpyrazolin-5-(4H-)-one in an ionic liquid (ethylammonium nitrate) afforded 3-methyl-4-[(1,3-diphenyl-1H--pyrazolo-4-yl)methylene]-1-phenylpyrazolin-5-(4H-)-ones in an excellent yield at room temperature.