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Indian Journal of Chemistry -Section B (IJC-B) >
IJC-B Vol.48B [2009] >
IJC-B Vol.48B(11) [November 2009] >
| Title: | Novel pyrazolopyrones from enol lactones |
| Authors: | Siddiqui, Zeba N
Asad, Mohammad |
| Keywords: | Triacetic acid lactone
4-hydroxycoumarin
5-chloro-3-methyl-1-phenylpyrazole-4-carboxaldehyde
5-azido-3-methyl-1-phenylpyrazole-4-carboxaldehyde
pyrazolopyrones |
| Issue Date: | Nov-2009 |
| Publisher: | CSIR |
| Abstract: | The one pot and facile condensation reaction of 5-chloro-3-methyl-1-phenylpyrazole-4-carboxaldehyde 1, 5-azido-3-methyl-1-phenylpyrazole-4-carboxaldehyde 2 with triacetic acid lactone 3 and 4-hydroxycoumarin 4 affords isomeric pyrazolopyrones viz. 4-(4-hydroxy-6-methyl-2-oxo-2H-pyran-2-one-3-yl)-3,7-dimethyl-1-phenylpyrazolo[3,4:2,3]-4H-pyrano [3,2-b]pyran-5-one 6, 4-(4-hydroxy-6-methyl-2-oxo-2H-pyran-2-one-3-yl)-3,7-dimethyl -1-phenylpyrazolo[3,4:2,3]-4H-pyrano[3,2-c]pyran-5-one 7 and 4-(4-hydroxy-2-oxo-2H-1-benzopyran-2-one-3-yl)-3-methyl-1-phenylpyrazolo[3,4:2,3]-4H-pyrano[3,2-b]-1-benzopyran-5-one 8, 4-(4-hydroxy-2-oxo-2H-1-benzopyran-2-one-3-yl)-3-methyl-1-phenylpyrazolo[3,4:2,3]-4H-pyrano[3,2-c]-1-benzopyran-5-one 9 respectively. The condensation reaction which has led to the formation of isomeric compounds is similar to Simonis condensation reaction of oxoesters. The structures of all newly synthesized compounds have been determined by IR, 1H NMR and mass spectral data. |
| Page(s): | 1609-1613 |
| ISSN: | 0975-0983(Online); 0376-4699(Print) |
| Source: | IJC-B Vol.48B(11) [November 2009]
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