الفهرس 
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Abstract
Utility of Agricultural Wastes in Synthesis of Homo and Utility of Agricultural Wastes in Synthesis Homo and Heterocyclic Compounds with Anticipated Biological Activity. Heterocyclic Compounds with Anticipated Biological Activity. This investigation deals with the utility of agricultural wastes in the synthesis of new homo and heterocyclic compounds in a trial of obtaining new compounds with higher biological activity. The work is arranged in four parts:- Part 1:- Facile Synthesis of Biologically Active Nitrogenous Heterocycles Incorporating Pyrogallol Moiety. In this part a series of nitrogenous heterocyclic derivatives linked to a pyrogallol residue and their N-nucleosides were synthesized to evaluate their antioxidant and antitumor activities. Thus, acid catalyzed reaction of the acetophenone derivatives 25, 26 and 27 with 2-cyanoacetohydrazide in ethanol at room temperature led to the formation of the corresponding hydrazones Ia, Ib and Ic, respectively (Scheme 1). Reaction of the hydrazone Ia with 4-methoxybenzylidene malononitrile in ethanol and in the presence of piperidine as a catalyst led to the formation of the corresponding pyridone derivative IIa. By the same manner, the hydrazone Ib reacted with 4-methylbenzylidene malononitrile to yield the pyridone derivative IIb (Scheme 1). On the other hand, stirring of the acetophenone derivative 25 with thiosemicarbazide in glacial acetic acid and in the presence of few drops of triethylamine gave the corresponding semicarbazone derivative III. Whereas, reaction of 25 with benzothiazol-2-yl-acetic acid hydrazide in ethanol and in the presence of few drops of concentrated sulfuric acid yielded compound IV (Scheme 1).
Summary
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OR1OR2OR325: R1 = R2 = R3 =H26: R1 = H; R2 = R3 =CH327: R1 = R2 = R3 =CH3RCHC(CN)2EtOH / PipEtOH, Conc H2SO4EtOH/ Conc H2SO4AcOH, TEAIa or IbIa-cIa: R1 = R2 = R3 =HIb: R1 = H; R2 = R3 =CH3Ic: R1 = R2 = R3 =CH3COCH3CH2CONHNH2CNCOR1OR2OR3NCH3NHCOCH2CNNH2CSNHNH2SNCH2CONHNH2OHOHOHCNNHCSNH2CH32525R2OOR1OHCH3NNH2NNCCNORIIa,bIIa, R=OMe; R1=R2=H IIb, R=Me; R1=R2=CH3COHOHOHCH3NNHCOCH2SNIVIII Scheme 1 On the other hand, acid catalyzed reaction of the acetophenone derivatives 25, 26 and 27 with phenylhydrazine led to the formation of the hydrazone derivatives Va, Vb and Vc, respectively (Scheme 2). The Vilsmeier-Haack reaction of the hydrazone derivatives Va-c using 2.5 equivalent of phosphorous oxychloride performed a double addition of reagent to afford, ultimately after hydrolysis, the desired aldehydes VIa, VIb and VIc, respectively (Scheme 2). The chemical behavior of the aldehydes VIa-c added a further proof to the given structure. Thus, the aldehydes VIa-c upon treatment with 2,4-
Summary
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dinitrophenyl hydrazine in glacial acetic acid under heating for a few minutes gave the corresponding hydrazones VIIa-c (Scheme 2). Condensation of compound VIb with cyanoacetyl urea by heating under reflux in glacial acetic acid and in the presence of triethylamine led to the formation of VIII in good yield (Scheme 2).
Knoevenagel condensation of 3-(2-hydroxy-3,4-dimethoxyphenyl)-1-phenyl-1H-pyrazole-4-carbaldehyde VIb with ehylcyanoacetate and/ or malononitrile gave compounds IXa and IXb , respectively (Scheme 3). Reaction of compound IXb with thiourea by refluxing in sodium ethoxide solution gave the pyrimidine derivative X (Scheme 3). Coupling of the aglycon X with sodium hydride in dry N, N-dimethylformamide followed by addition of the activated sugar 2`,3`,4`,6`-tetra-O-acetyl-α-D-glucopyranosyl bromide XI gave the corresponding N-glycoside derivative XII (Scheme 3).