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Abstract 2(3H)-Furanones are important types of five membered heterocyc1ic compounds .The chemistry of furanones has received considerable attention owing to their synthetic and effective biological importance. These compounds are characterized by facile ring opening with nucleophiles to give acyclic products which on ring closure afford a wide variety of biologically importance heterocycles. This thesis will deal with the synthesis of arylidene derivatives of 5- aryl-2(3.H)-furanones and with the use of these compounds as versatile synthons in the synthesis of a number of heterocyclic compounds. Biological acitivity studies are also performed on selected examples of the compounds obtained. The first part of this investigation deals with the synthesis of 3- (arylidene )-5( 4-methoxy-3-nitrophenyl)-2(3H)-furanone 2a-d and their reaction towards some nucleophiles (Scheme I). The starting material 3- (arylidene )-5( 4-methoxy-3-nitrophenyl)-2(3H)-furanone 2a-d were prepared by a method described in the literature i.e. by Perkin- Erlenmeyer condensation of 4-[ 4-methoxy-3-nitrophenyl]-4-oxobutanoic acid 1 with aldehyde in presence of acetic anhydride and sodium acetate. Synthesis of 3 [2-oxo-5-( 4-methoxy-3-nitrophenyl)-2(3H)- furylidene] phthalide 3 has been achieved by refluxing 4-[4-methoxy-3- nitrophenyl]-4-oxobutanoic acid 1, phthalic anhydride, fused sodium acetate in acetic anhydride. Treatment of 3-(arylidene )-5-( 4-methoxy-3-nitrophenyl)-2(3H)- furanone 2a-c with benzyl amine in ethanol under reflux led to the formation of 3-(arylidene)- I-benzyl -5(4-methoxy-3-nitrophenyl)- 2(3H)-pyrrolones 4a-c . The reaction of 3-(benzylidene)-5( 4-methoxy-3-nitrophenyl)-2(3H)- furanone 2 with ethanol amine in ethanol under reflux led to the formation of 3-( benzylidene )-1-(2-hydroxy ethyl) -5( 4-methoxy-3-nitro phenyl)- 2(3H)-pyrrolone 5. Synthesis of 6 has been achieved by refluxing of 3-(4- chlorobenzylidene)-5(4-methoxy-3-nitrophenyl)-2(3H)-furanone 2 with Hydroxyl amine hydrochloride in pyridine. Hydrazinolysis of3-(arylidene)-5-(4-methoxy-3-nitrophenyl)-2(3H)- furanones 2a-d in ethanol at room temperature afforded the corresponding 3-( 4-methoxy-3-nitrobenzoyl)-2-(arylidene)-propionic acid hydrazides 7a-d. Cyclization of3-(4-methoxy-3-nitrobenzoyl)-2-(arylidene)-propionic acid hydrazides 7a-d by refluxing with cone HCI in presence of acetic acid led to the formation of 4-(aryl methyl) - 6-(4-methoxy-3-nitro phenyl) -3(2H)-pyridazinones Sa-d . Benzoylation of 3-( 4-methoxy-3-nitrobenzoyl)-2-(arylidene)- propionic acid hydrazides 7a-c with benzoyl chloride in dry benzene led to the formation of I-benzoyl-4-(arylidene)-6-(4-methoxy-3- nitrophenyl)-l ,2-dihydro-3-pyridazinones 9a-c. |