SYNTHESIS OF 4-HYDROXY-3-SUBSTITUTED COUMARINS OF EXPECTED BIOLOGICAL ACTIVITY AND THEIR REACTIONS WITH SOME NUCLEOPHILES | ||
| Al-Azhar Bulletin of Science | ||
| Article 16, Volume 2008, Issue 12, December 2008, Pages 213-224 PDF (297.06 K) | ||
| Document Type: Original Article | ||
| DOI: 10.21608/absb.2008.10837 | ||
| Authors | ||
| NAHED F. ABD EL-GHAFFAR* ; NADIA T. DAWOOD; FATMA H. ABD EL-SALAM; AWTIF E. FARRAG | ||
| Chemistry Department, Faculty of Science, Al-Azhar University, Nasr City, Cairo | ||
| Abstract | ||
| 3-Acetyl-4-hydroxy substituted coumarins (IIa-c) were prepared. Their reactions with hydrazines in DMF gave the corresponding 4-hydroxy -(3-substituted pyrazolin-3-yl)coumarins (IVa-f) via the intermediate hydrazone (III). Their reaction with hydroxylamine hydrochloride gave the corresponding isoxazol-3-yl coumarin (VIa-c) and (VIIa,b) via the oxime intermediate (V). Reaction of II with aromatic aldehydes gave the corresponding chalcone derivatives (VIIIa-k) which were reacted with hydrazines and hydroxyl amine hydrochloride and gave (IXa) and (Xa-c). Condensation of (IIa-c)with aromatic aldehydes, malononitrilein the presence ammonium acetate yielded the corresponding 3-cyano-4-aryl nictoinamido-6-yl-coumarin (XIa-f). 4-Hydroxy comumarin (1a-c) on treatment with POCl3 in DMF give the corresponding 4-Chloro-3-formyl coumarin (XIIa-c) which on treatment with sod azide gave the corresponding 4-azido-3-formyl coumarin (XIIIa-c). 4-chloro-3-formyl coumarine (XII )on treatment with hydrazine gave pyrazolo coumarin derivatives (XIVa-d) and on treatment with hydroxylamine hydrochloride gave 4-chloro-3-aldo oxime coumarin derivatives (XVa,b).On treatment of 4-azido-3-formyl coumarin with active methylene compounds such as malononitrile and ethyl cyanocetate derivatives gave (XVIa-d) respectively. The antibacterial and antifungal activities of some compounds have been described. | ||
| Keywords | ||
| 4-HYDROXY-3-SUBSTITUTED | ||
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