الفهرس 
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Abstract
Chalcones, considered to be the precursor of flavonoids and
isoflavonoids, are abundant in edible plants. They consist of open-chain
flavonoids in which the two aromatic rings are joined by a three-carbon α,
β-unsaturated carbonyl system.
In the present investigation, we tried to apply the microwave
irradiation on the synthesis of chalcone derivatives by irradiated
acetophenone (1) and benzaldehyde (2) for 3 min. to afford the
corresponding chalcone (3) in 99 % yield (Scheme 1).
3,5-Diphenyl-4,5-dihydro-1H-pyrazole (4) was synthesized in 98
% yield by treating of 3 with hydrazine hydrate under microwave
irradiation for 3 min (Scheme 2).
1,3,5-Triphenyl-4,5-dihydro-1H-pyrazole (5) was synthesized in 99
% yield by treating of 3 with phenyl hydrazine under microwave
irradiation for 3 min (Scheme 3).
2,3-Dibromo-1,3-diphenylpropan-1-one (6) (2,3-dibromochalcone)
was synthesized in 97 % yield by treating of 3 with bromine water in
chloroform under microwave irradiation for 3 min (Scheme 4).
MW 3 min.
Et3N/benzene
4-(β-D-Glucopyranosylamino)acetophenone (10) was synthesized
by two methods. Treating of 4-aminoacetophenone (8) with D-glucose (9)
in ethyl alcohol and in the presence of a catalytic amount of glacial acetic
acid at reflux temperature gave 10 in 89 % yield. On the other hand, the
same compound was synthesized in 99 % yield by microwave irradiation
for 3 min (Scheme 5).
4-(2,3,4,6-Tetra-O-acetyl-β-D-glucopyranosylamino)acetophenone
(11) was synthesized in 91 % yield by treating of 10 with acetic
anhydride in dry pyridine at room temperature (Scheme 6).
4-(β-D-Glucopyranosylamino)chalcone (12) was synthesized by two
methods. Treating of 10 with benzaldehyde in ethyl alcohol and in the
presence of sodium hydroxide as a base at heating temperature afforded
12 in 86 % yield. On the other hand, the same compound was synthesized
in 98 % yield by microwave irradiation for 3 min (Scheme 6).
4-(β-D-Galactopyranosylamino)acetophenone (14) was synthesized
by two methods. Treating of 4-aminoacetophenone (8) with D-galactose
(13) in ethyl alcohol and in the presence of a catalytic amount of glacial
acetic acid at reflux temperature gave 10 in 85 % yield. On the other
hand, the same compound was synthesized in 97 % yield by microwave
irradiation for 3 min (Scheme 7).
4-(2,3,4,6-Tetra-O-acetyl-β-D-galactopyranosylamino)
acetophenone (15) was synthesized in 88 % yield by treating of 14 with
acetic anhydride in dry pyridine at room temperature (Scheme 8).
4-(β-D-Galactopyranosylamino)chalcone (16) was synthesized by two
methods. Treating of 14 with benzaldehyde in ethyl alcohol and in the
presence of sodium hydroxide as a base at heating temperature afforded
16 in 84 % yield. On the other hand, the same compound was synthesized
in 99 % yield by microwave irradiation for 3 min (Scheme 8).
HN
C
14
O
HO OH
O
CH3
HN
C
15
O
AcO OAc
O
CH3
HN
C
16
O
HO OH
O
CH
CH
Ac2O/Py/r.t
PhCHO/NaOH/EtOH
HO OH
AcO OAc
HO OH
Scheme 8
MW 3 min.
4-(β-D-Mannopyranosylamino)acetophenone (18) was synthesized
by two methods. Treating of 4-aminoacetophenone (8) with D-mannose
(17) in ethyl alcohol and in the presence of a catalytic amount of glacial
acetic acid at reflux temperature gave 10 in 84 % yield. On the other
hand, the same compound was synthesized in 99 % yield by microwave
irradiation for 3 min (Scheme 9).
4-(2,3,4,6-Tetra-O-acetyl-β-D-mannopyranosylamino)
acetophenone (19) was synthesized in 92 % yield by treating of 18 with
acetic anhydride in dry pyridine at room temperature (Scheme 10).
4-(β-D-Mannopyranosylamino)chalcone (20) was synthesized by two
methods. Treating of 18 with benzaldehyde in ethyl alcohol and in the
presence of sodium hydroxide as a base at heating temperature afforded
20 in 89 % yield. On the other hand, the same compound was synthesized
in 97 % yield by microwave irradiation for 3 min (Scheme 10).
Diazotization of 4-aminoacetophenone (8) followed by coupling
with 2-naphthol (22) afforded 1-[4-(2-hydroxynaphtholazo)]
acetophenone (23) in 80 % yield (Scheme 11).
NaNO2,HCl
OH NaNO2,HCl
OH
OH
N N C
23
H2N C
8
O
CH3 ClN2 C
21
O
CH3
22
O
CH3
Scheme 11
1-[4-(2-Hydroxynaphtholazo)]chalcone (24) was synthesized by two
methods. Treating of 23 with benzaldehyde in ethyl alcohol and in the
presence of sodium hydroxide as a base at heating temperature afforded
20 in 65 % yield. On the other hand, the same compound was synthesized
in 97 % yield by microwave irradiation for 3 min (Scheme 12).
1-[4-(2-Hydroxynaphtholazo)]-2,3-dibromochalcone (25) was
synthesized in 49 % yield by treating of 24 with bromine water in
chloroform under microwave irradiation for 3 min (Scheme 12).
Diazotization of 4-aminoacetophenone (8) followed by coupling with
1-naphthol (26) afforded 4-[4-(1-hydroxynaphtholazo)]acetophenone (27)
in 72 % yield (Scheme 13).
4-[4-(1-Hydroxynaphtholazo)]chalcone (28) was synthesized by two
methods. Treating of 27 with benzaldehyde in ethyl alcohol and in the
presence of sodium hydroxide as a base at heating temperature afforded
28 in 46 % yield. On the other hand, the same compound was synthesized
in 94 % yield by microwave irradiation for 3 min (Scheme 13).
Diazotization of 4-aminoacetophenone (8) followed by coupling with
resorcinol (29) afforded 1-[4-(2,4-dihydroxybenzeneazo)]acetophenone
(30) in 73 % yield (Scheme 14).
1-[4-(2,4-Dihydroxybenzeneazo)]chalcone (31)was synthesized by
two methods. Treating of 30 with benzaldehyde in ethyl alcohol and in
the presence of sodium hydroxide as a base at heating temperature
afforded 31 in 47 % yield. On the other hand, the same compound was
synthesized in 98 % yield by microwave irradiation for 3 min (Scheme
14)