الفهرس 
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Abstract
To a solution of the thiol (5 g, 31 mmol) in ethanol, hydrazine hydrate (3.1 g, 62mmol) was added. The mixture was heated under reflux
for 30 min. The solid product formed after cooling was collected by
filtration, to afford yellow powder precipitate in 85% yield(Scheme 1).
Reaction with sugar:
A mixture of compound (1) (0.48g, 3mmol), appropriate sugar (3.1
mmol) , (15 ml)absolute ethanol and catalytic amount of glacial acetic
acid (3 drops) was heated under reflux for 6h.the formed precipitate was
filtered off, dried and recrystallized from ethanol (Schemes2-5).
Summary
II
Summary
III
Cyclization:
A mixture of compound 2-5(0.5g, 1.6m mol) was dissolved in suitable
amount of acetic anhydride. The reaction mixture was heated under reflux
for 6h. The reaction mixture was poured into ice water and extracted with
ethyl acetate. Organic layers were collected, dried with calcium chloride
anhydrous and filtered and the solvent was evaporated under reduced
pressure( schemes6-9).
Summary
IV
N
N
NHN
HO
OH
CH2OH
OH
HO
Reflux
Scheme 8
4 8
Ac2O
N
N
N N
Ac
OAc
OAc OAc
OAc
CH2OA
c
Acetylation:
A solution of compound 2-3-4-5 (0.5g, 1.6mmol) in a mixture of
acetic anhydride (10ml) and anhydrous pyridine (10ml) was stirred at
room temperature for 24h.the reaction mixture was poured into ice water
and extracted with ethyl acetate. Organic layers were collected, dried with
calcium chloride anhydrous , filtered and the solvent was evaporated
under reduced pressure(schemes 10-13).
Summary
V
Scheme 10
4
N
N
NHN
HO
OH
CH2OH
OH
HO
N
N
NHN
AcO
OAc
CH2OAc
OAc
AcO
Ac2O/Stirring
Pyridine
10
Summary
VI
Scheme 13
N
N
NHN
HO
OH
OH
CH2OH
N
N
NHN
AcO
OAc
OAc
CH2OAc
AC2O/Stirring
Pyridine
5 13
Prepration of reagent:
A mixture of anhydrous sodium acetate (0.98 g, 12 mmol),hippuric acid
(3.3 g, 12 mmol), (10 ml) of acetic anhydride and theappropriate
aldehyde or ketone was heated for 3h. The solid product formed was
collected by filtration( scheme14).
Scheme 14
HN Ph
COOH
O
N O
O
OMe
Ph
MeO CHO H
Ac2O/Sod acetate
N O
O
Cl
Ph
H
Cl CHO
Ac2O/Sod acetate
14
15
Summary
VII
Reaction with reagent:
A mixture of compound 1(0.1 g, 0.57 mmol) and 14 or 15 (0.57 mmol) in
(20 ml) of dioxane and acetic acid (3drops) was refluxed for 24h. The
reaction mixture was poured into ice water. The solid product formed was
collected by filtration (scheme15).
Reaction of 1 with aldehydes:
A mixture of 2 (0.3g, 1.9m mol) and appropriate aldehyde (1.9m mol) in
(10 ml) of ethanol in the presence of few drops of glacial acetic acid was
refluxed for 6h(scheme16).