الفهرس 
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Abstract
The present work is derived to three parts
Part (I)
In this part 579a,b were allowed to react with ethyl chloroacetate in dry acetone and in the presence of anhydrous potassium carbonate to afford the corresponding ester derivatives 580a,b in 85-92% yields. The acid hydrazides 581a,b were synthesized, in 97-98% yields, by refluxing its corresponding ester derivatives with hydrazine hydrate in ethanol (Scheme 1).
When the hydrazides 581a,b were reacted with the respective monosaccharides (D-xylose, D-glucose or D-galactose) in an aqueous ethanolic solution and a catalytic amount of glacial acetic acid, gave the corresponding hydrazinosugar derivatives 582-587 in 75-87% yields, respectively (Scheme 2).
Acetylation of the sugar hydrazones 582-587 with acetic anhydride in pyridine at room temperature gave the corresponding per-O-acetyl derivatives 588-593 in 80-97% yields. Heating hydrazones 582-587 with acetic anhydride at (120 oC , 1.5 h ) afforded the corresponding oxadiazoline derivatives 594-599 in 73-84% yields (Scheme 3).
When 600 was allowed to react with ethyl chloroacetate in dry acetone and in the presence of anhydrous potassium carbonate afforded the corresponding ester derivative 601 in 84% yield. The acid hydrazide 602 was synthesized, in 98% yield, by refluxing its corresponding ester derivatives 601 with hydrazine hydrate in ethanol (Scheme 4).
When the hydrazide 602 was reacted with the respective monosaccharides (D-xylose, D-glucose or D-galactose) in an aqueous ethanolic solution and a catalytic amount of glacial acetic acid, gave the corresponding hydrazinosugar derivatives 603-605 in 80-84% yields, respectively (Scheme 4).
Acetylation of the sugar hydrazones 603-605 with acetic anhydride in pyridine at room temperature gave the corresponding per-O-acetyl derivatives 606-608 in 95-97% yields. Heating of the sugar hydrazones 603-605 with acetic anhydride (120 oC, 1.5 h) afforded the corresponding oxadiazoline derivatives 609-611 in 85-87% yields (Scheme 5).
When 579a,b and 600 were allowed to react with 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide in dry acetone and in the presence of anhydrous potassium carbonate gave the corresponding acetylated thioglucosides 612,613 and 616 in 88-95% yields (Scheme 6 and 7).
Deprotection of the acetyl groups was carried out by using ammonia in methanol at room temperature afforded the corresponding free hydroxyl thioglucosides 614,615 and 617 in 85-93% yields (Scheme 6 and 7).
Part (II)
This part deals with the synthesis of hydrazino-1,2,4-Triazole derivatives 618, 627 by the reaction of 579 b, 600 with hydrazine hydrate in ethanol and reflux temperature for 6 h. The compound of 618 was utilized in preparing a series of condensed heterocyclic compounds (Scheme 8).
The reaction of 618 with carbon disulphide in the presence of alcoholic potassium hydroxide and subsequent acidification gave 619. Also 618 was reacted with sodium nitrite and hydrochloric acid to give 620. Condensation of 618 with 1,3-dicarbonyl compounds gave the respective pyrazole and pyrazolidinone derivatives 621 and 622, respectively (Scheme 8).
When 618 was allowed to react with a number of monosaccharide, the corresponding sugar hydrazones 623 and 624 were obtained. The boiling of sugar hydrazones with acetic anhydride gave 625 and 626 (Scheme 9).
By the same way, the reaction of the hydrazide 627 with carbon disulfide, sodium nitrite, 1,3-dicarbonyl gave 628-631 derivatives respectively (Scheme 10).
Also, when 627 was reacted with monosaccharides gave 632 and 633 which under boiling with acetic anhydride gave 634 and 635 (Scheme 11).
Part (III)
This part deals with the synthesis of 4-Amino-5-[(2-methylquinazolin-4-yloxy)methyl]-4H-1,2,4-triazole-3-thiol 636 which was reacted with ethylchloroformate in the presence of sodium methoxide affording the cyclized product 637, and when reacted with carbon disulphide and benzoyl chloride in the presence of pyridine gave 638 and 640, respectively. Reaction of 636 with sodium nitrite in hydrochloric acid gave 639. Reaction of 636 with phenyl isothiocyanate under reflux in DMF gave the corresponding thiosemicarbazide derivative 641. Cyclocondensation of SH and NH2 functional groups of 636 with aromatic carboxylic acids and oxalic acid in the presence of phosphoryl chloride gave 642-644, respectively. Treatment of 636 with ethylcyanoacetate in polyphosphoric acid afforded 645. Nitrosation of 645 with sodium nitrite in the the presence of acetic acid gave 646. When 636 was reacted with some aromatic aldehydes (namely:benzaldehyde, 4-bromobenzaldehyde, naphthalene-2-carbaldehyde, 4-amino-3,5-dimethylbenzaldehde), the corresponding Schiff base derivatives 647-650 were obtained (Scheme 12).
On the other hand, the reaction of 636 with chloroacetic acid in the presence of sodium acetate gave 651 and with phenacylbromide in ethanol afforded 652. When 636 was treated with 1,3-diphenyl-1,3-propendione in the presence of potassium hydroxide in ethanol gave 653 and when reacted with phenyl isothiocyanate at room temperature in DMF gave 654. Finally 636 was allowed to react with phthalic anhydride in butanol gave 655 (Scheme 13).
The antitumor and antimicrobial activities of the prepared compounds were evaluated. The activities varied from moderate to high for the most of tested compounds.