الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 219 |  |  |
| | | from | 219 | | |
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 Ophenylenediamine
,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-phenylhydrazinecarbothioamide
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-1Hbenzimidazol-
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-Dglucopyranosyl
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.