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.
How to Cite This Article
ABD EL-GHAFFAR, NAHED; DAWOOD, NADIA; ABD EL-SALAM, FATMA; and FARRAG, AWTIF
"SYNTHESIS OF 4-HYDROXY-3-SUBSTITUTED COUMARINS OF EXPECTED BIOLOGICAL ACTIVITY AND THEIR REACTIONS WITH SOME NUCLEOPHILES,"
Al-Azhar Bulletin of Science: Vol. 19:
2, Article 23.