الفهرس 
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Abstract
Acid hydrazide of 2-methylbenzimidazole coupled with CS2 followed by reaction with α-acetobromoglucose to give their thioglucoside drivatives as well as coupling of the acid hydrazide with different aldehydes to produce Schiff`s bases followed by coupling with thioglycolic acid to produce thiazolidinone derivatives. Finally, coupling of the acid hydrazide with acyclic sugars afforded the acyclic nucleosides. Some of the prepared compounds were evaluated for their potential antimicrobial activity against Gram + ve and Gram – ve bacteria as well as some fungi and showed good results.
The starting material 2-methylbenzimidazole (23) was synthesized from O-phenylenediamine ,when compound 23 reacted with ethyl chloroacetate in the presence of potassium carbonate and dry acetone to afforded ethyl 2-(2-methyl-1H-benzimidazol-1-yl)acetate (141) in 60 % yield. Hydrazinolysis of 141 with hydrazine hydrate in ethanol afforded the corresponding acid hydrazide derivative 142.The latter was allowed to react with CS2 in ethanol in the presence of potassium hydroxide, the corresponding 1,3,4-oxadiazole-2(3H)-thione derivative 143 was afforded in 61% yield. Reaction of the thione derivative 143 with 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide (144) gave the corresponding acetylated thioglucoside 145 in 69% yield. Treatment of the acetylated thioglucoside 145 with methanolic ammonia gave the deacetylated thioglucoside derivative 146 (Scheme 1).
On the other hand, when the acid hydrazide 142 reacted with phenylisothiocyanate in ethanol it afforded N-phenylhydrazinecarbo-thioamide derivative 147 in 76.4% yield,which inturn reacted with variety of reagents and furnished five membered heterocycles thus, compound 147 reacted with conc. H2SO4 to afford 5-((2-methyl-1H-benzimidazol-1-yl)methyl)-N-phenyl-1,3,4-thiadiazol-2-amine (148) in 77.2% yield. Refluxing of 147 with bromoacetic acid afforded 2-(2-methyl-1H-benzimidazol-1-yl)methyl)-N-(4-oxo-2-(phenylimino)thiazolidin-3-yl)-acetamide (149) in 78% yield. While refluxing with 10% NaOH solution gave 2-(2-methyl-1H-benzimidazol-1-yl)-4-phenyl-1H-1,2,4-triazole-5(4H)-thione (151) in 93 % yield. Reaction of 150 with 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide (144) afforded the corresponding acetylated thioglucoside 151 in 76% yield. Treatment of the acetylated thioglucoside 151 with methanolic ammonia gave the deacetylated thioglucoside derivative 152 (Scheme 2).
On the other hand,the acid hydrazide 142 was allowed to react with different aldehydes gave the corresponding Shiff’s bases 153a-c in moderate yields. Reaction of 153a-c with thioglycolic acid afforded the thiazolidinone derivatives 154a-c, respectively. Reaction of 142 with acyclic sugars as D-(+)-xylose or D-(+)-glucose in an aqueous ethanolic solution and a catalytic amount of acetic acid, the corresponding sugar hydrazones 155a,b were obtained, respectively (Scheme 3).