Syntheses and reactions of 4'-[(ω-bromoalkyl)oxy]-and 4',4'''-(polymethylenedoxy)-bis substituted chalcones

Article abstract of DOI:10.1155/2010/807059

Base catalyzed condensation of 4-hydroxyacetophenone (1) with several aldehydes resulted 4'-hydroxychalcones (2a-c). Reaction of α,ω-dibromoalkanes (3, n=2, 4 & 6) with (2a-c) in equimolar ratio resulted a mixture of 4'-[(ω-bromoalkyl)oxy]- substituted chalcones (4a-i) and 4',4'''-(polymethylenedioxy)-bis substituted chalcones (5a-i) separated by ethanol as soluble (4a-i) and insoluble (5a-i) products. Compounds (5a-i) were also synthesized by another route. Compound 1 on treatment with 3 in molar ratio 2:1 resulted 4',4'''-(polymethylenedioxy)-diacetophenone (4^#a-c) which on base catalyzed condensation gave compounds (5a-i). Reaction of 4d with substituted phenols and thiophenols gave corresponding phenoxy and thiophenoxy substituted chalcones (6a-f) where as compounds 5a, 5b, 5d, 5h and 5e on treatment with hydrazine hydrate furnished corresponding bis-2-pyrazolines (7a-e). The structures of all synthesized compounds were confirmed on the basis of analytical and spectral data.

Full text of DOI:10.1155/2010/807059

ISSN: 0973-4945; CODEN ECJHAO
E-Journal of Chemistry
2010, 7(3), 763-769
http://www.e-journals.net
Syntheses and Reactions of 4′-[(ω-Bromoalkyl)oxy]-
and 4′,4′″-(Polymethylenedoxy)-bis
Substituted Chalcones
R. S. SODANI, PRAKASH C. CHOUDHARY,
HARI OM SHARMA and B. L. VERMA*
Department of Chemistry, University College of Science,
M. L. Sukhadia University, Udaipur- 313001 (Raj.), India.
blverma10@gmail.com
Received 30 September 2009; Accepted 25 November 2009
Abstract: Base catalyzed condensation of 4-hydroxyacetophenone (1) with
several aldehydes resulted 4′-hydroxychalcones (2a-c). Reaction of α,ω-
dibromoalkanes (3, n=2, 4 & 6) with (2a-c) in equimolar ratio resulted a
mixture of 4′-[(ω-bromoalkyl)oxy]- substituted chalcones (4a-i) and 4′,4′″-
(polymethylenedioxy)-bis substituted chalcones (5a-i) separated by ethanol as
soluble (4a-i) and insoluble (5a-i) products. Compounds (5a-i) were also
synthesized by another route. Compound 1 on treatment with 3 in molar ratio
2:1 resulted 4′,4′″-(polymethylenedioxy)-diacetophenone (4#a-c) which on
base catalyzed condensation gave compounds (5a-i). Reaction of 4d with
substituted phenols and thiophenols gave corresponding phenoxy and
thiophenoxy substituted chalcones (6a-f) where as compounds 5a, 5b, 5d, 5h
and 5e on treatment with hydrazine hydrate furnished corresponding bis-2-
pyrazolines (7a-e). The structures of all synthesized compounds were
confirmed on the basis of analytical and spectral data.
Keywords: Chalcones, Bromoalkoxychalcones, Polymethylenedioxychalcones, Bis-2-pyrazolines.
Introduction
Chalcones are natural or synthetic compounds bearing the 1,3-diphenylpropenone framework.
Depending on the substitution pattern on the two aromatic rings, a wide range of
pharmacological activities have been identified for various chalcones. These include among
others, cytotoxic, antitumor, antiviral and antiprotozoal activities1,2. More recently, there has
been strong interest in the potential antimalarial3 activity of chalcones and bis-chalcones. The
antimalarial activity of chalcones was first noted when lipochalcone-A, a natural product
isolated from Chinese liquorice roots, was reported to exhibit potent in vivo and in vitro
antimalarial activity4. Subsequently, a synthetic analogue, 2,4-dimethoxy-4′- butoxychalcone

764
B. L. VERMA et al.
was reported to have outstanding antimalarial activity5. Variously substituted pyrazolines and
their derivatives are important biological agents and a significant amount of research activity has
been directed towards this class6-10. Prompted by the varied biological activities of the chalcones,
bis-chalcones and pyrazolines and in continuation to our work on 4′-alkoxy substituted
chalcones11 and other substituted analogues12-15 for biological evaluation and synthesis of
variously sized heterocycles it was contemplated in this present work to synthesize variously
substituted 4′-[(ω-bromoalkyl)oxy]chalcones, 4′,4′″-polymethylenedioxybischalcones and
4′,4′″-polymethylenedioxy-bis-2-pyrazolines.
Experimental
All melting points were determined in open capillaries in liquid paraffin bath and are
uncorrected. The IR spectra were recorded on Perkin-Elmer-783 spectrophotometer (טmax in cm-1)
using KBr pellets. 1H NMR spectra were recorded on a Bruker DRX-300 MHz
spectrophotometer (δ, ppm) using CDCl3 / DMSO-d6 as a solvent and TMS as internal
standard. The purity of the compounds was checked by TLC on silica gel coated glass
plates. The elemental analyses were performed on Carlo-Erba-1108 analyzer and were within
0.5% of the calculated values. Syntheses of 4′-hydroxychalcones and α,ω-dibromoalkanes (Br-
(CH2)n-Br: n= 2,4 & 6) were carried out by literature methods16.
General procedure for the preparation of 4
′-[(ω-bromoalkyl) oxy]- substituted
chalcones (4a-i) and 4′,4′″-(polymethylenedioxy)-bis substituted chalcones (5a-i)
An appropriate 4′-hydroxy chalcone 2 (0.01 mol) and α,ω-dibromoalkane 3 (0.01 mol)
(n = 2, 4 or 6) in dry acetone (100 mL) and anhydrous potassium carbonate (0.02 mol) were
refluxed (10-15 h). The completion of the reaction was judged by negative test with alcoholic
ferric chloride. After completion of the reaction, acetone was distilled off and the residue in the
flask was treated with ice cold water and stirred well. Separated solid was filtered and washed
with 5% NaOH solution and finally with water (3 x 30 mL). The solid was dried, dissolved in
boiling ethanol and filtered hot. Some solid remains insoluble which was washed again with hot
ethanol. The filtrate after concentration afforded a solid which on crystallization from proper
solvent gave compounds (4a-i). Whereas ethanol insoluble solid resulted bis chalcones (5a-i)
4a: Pale yellow (methanol): yield 65%: m.p. 96 °C: IR (KBr): 3050 (Ar-H), 2910,2860
(C-H): 1660 (C=O), 1600, 1500 (C=C), 1250 (asym. C-O-C): 1030 (sym. C-O-C): 1H NMR (δ,
CDCl3): 3.65, (t, 2H, -CH2Br): 4.40 (t, 2H, -OCH2-): 6.90-8.10 (m, 10H, Ar-H & olefinic
protons): Anal. (%) Calcd. for C17H15BrO2 (331.20): C, 61.65: H, 4.56. Found C, 61.35: H, 4.30.
4b: Pale yellow (methanol): yield 60%: m.p. 103 °C: IR (KBr): 3080 (Ar-H), 2910 (C-H): 1660
1
(C=O), 1600, 1520 (C=C), 1220 (asym. C-O-C): 1040 (sym. C-O-C): H NMR (δ, CDCl3): 3.65, (t,
2H, -CH2Br): 3.85 (s, 3H, -OCH3): 4.35 (t, 2H, -OCH2-): 6.80-8.10 (m, 10H, Ar-H & olefinic
protons): Anal. (%) Calcd. for C18H17BrO3 (361.23): C, 59.85: H, 4.74. Found C, 59.57: H, 4.57.
4c: Colourless (ethanol): yield 70%: m.p. 145 °C: IR (KBr): 3060 (Ar-H), 2900 (C-H):
1660 (C=O), 1600, 1500 (C=C), 1230 (asym. C-O-C): 1020 (sym. C-O-C): Anal. (%) Calcd.
for C17H14 BrClO2 (365.65): C, 55.84: H, 3.85. Found C, 56.93, H, 3.93.
4d: Pale yellow (methanol): yield 60%: m.p. 113 °C: IR (KBr): 3050 (Ar-H),
2900,2850 (C-H): 1660 (C=O), 1600, 1510 (C=C), 1240 (asym. C-O-C): 1030 (sym. C-O-
C): Anal. (%) Calcd. for C19H19BrO2 (359.25): C, 63.50: H, 5.29. Found C, 63.32, H, 5.54.
4e: Pale yellow (methanol): yield 60%: m.p. 110 °C: IR (KBr): 3080 (Ar-H), 2900 (C-
H): 1660 (C=O), 1600, 1570, 1510 (C=C), 1220 (asym. C-O-C): 1040 (sym. C-O-C): Anal.
(%) Calcd. for C20H21O3Br (389.28): C, 61.71: H, 5.44: Found C, 61.32, H, 5.36.
4f: Colourless (ethanol): yield 70%: m.p. 116 °C: IR (KBr): 3060 (Ar-H), 2910 (C-H):

Syntheses and Reactions of Substituted Chalcones
765
1660 (C=O), 1600, 1500 (C=C), 1230 (asym. C-O-C): 1030 (sym. C-O-C): Anal. (%) Calcd.
for C19H18 BrClO2 (393.70): C, 57.96: H, 4.61. Found C, 57.70, H, 4.56.
4g: Colourless (methanol): yield 65%: m.p. 88 °C: IR (KBr): 3050 (Ar-H), 2900 (C-H):
1650 (C=O), 1600, 1570 (C=C), 1230 (asym. C-O-C): 1040 (sym. C-O-C): Anal. (%) Calcd.
for C21H23 BrO2 (387.30): C, 65.12: H, 5.99. Found C, 65.42, H, 6.12.
4h: Colourless (ethanol): yield 70%: m.p. 90 °C: IR (KBr): 3070 (Ar-H), 2940,2880
(C-H): 1660 (C=O), 1600, 1570, 1510 (C=C), 1220 (asym. C-O-C): 1030 (sym. C-O-C):
Anal. (%) Calcd. for C22H25O3Br (417.35): C, 63.30: H, 6.03. Found C, 63.48, H, 5.97.
4i: Colourless (methanol): yield 60%: m.p. 117 °C. IR (KBr): 3040 (Ar-H), 2940,2860
(C-H): 1660 (C=O), 1600, 1580, 1500 (C=C), 1260 (asym. C-O-C): 1040 (sym. C-O-C):
Anal. (%) Calcd. for C21H22BrClO2 (421.75): C, 59.80: H, 5.26. Found C, 59.65, H, 5.20.
5a: Colourless (CHCl3): yield 16%: m.p. 188°C: IR (KBr): 3030 (Ar-H), 2960,2900
(C-H): 1660 (C=O), 1600, 1500 (C=C), 1230 (asym. C-O-C): 1040 (sym. C-O-C): Anal. (%)
Calcd. for C32H26O4 (474.56): C, 81.01: H, 5.48. Found C, 80.90, H,5.5.
5b: Colourless (CHCl3): yield 20%: m.p. 201 °C: IR (KBr): 3050 (Ar-H), 2940,2860
(C-H): 1660 (C=O), 1610, 1590 (C=C), 1220 (asym. C-O-C): 1030 (sym. C-O-C): Anal. (%)
Calcd. for C34H30O6 (534.59): C,76.39: H, 5.66. Found C, 76.24, H, 5.55.
5c: Colourless (dioxan): yield 26%: m.p. 260 °C: IR (KBr): 3040 (Ar-H), 2950,2880
(C-H): 1650 (C=O), 1600, 1580 (C=C), 1240 (asym. C-O-C): 1040 (sym. C-O-C): Anal. (%)
Calcd. for C32H34Cl2O4 (543.44): C, 70.72: H, 4.45. Found C, 70.82, H,4.39.
5d: Colourless (CHCl3): yield 16%: m.p. 180 °C: IR (KBr): 3060, 3020 (Ar-H),
2900,2840 (C-H): 1640 (C=O), 1600, 1570 (C=C), 1260 (asym. C-O-C): 1050 (sym. C-O-C):
Anal. (%) Calcd. for C34H30O4 (502.59): C, 81.25: H, 6.02. Found C, 81.02, H,5.80.
5e: Colourless (dioxane-alcohol: 80:20 v/v): yield 18%: mp. 200 °C: IR (KBr): 3050 (Ar-
H), 2950,2850 (C-H): 1660 (C=O), 1600, 1530 (C=C), 1280 (asym. C-O-C): 1040 (sym. C-O-
C): Anal. (%) Calcd. for C36H34O6 (562.62): C, 76.86: H, 6.09. Found C, 76.70, H, 6.16.
5f: Pale yellow (CHCl3): yield 28%: m.p. 240 °C: IR (KBr): 3040 (Ar-H), 2900,2860
(C-H): 1660 (C=O), 1590, 1500 (C=C), 1250 (asym. C-O-C): 1030 (sym. C-O-C): Anal. (%)
Calcd. for C34H28O4Cl2 (571.48): C,71.46: H,4.94. Found C,71.20, H,4.82.
5g: Colourless (CHCl3): yield 20%: m.p. 182 °C: IR (KBr): 3050 (Ar-H), 2970,2880
(C-H): 1660 (C=O), 1600, 1510 (C=C), 1230 (asym. C-O-C): 1020 (sym. C-O-C): Anal. (%)
Calcd. for C36H34O4 (530.65): C, 81.48: H, 6.46. Found C, 81.20, H,6.50.
5h: Colourless (CHCl3): yield 21%: m.p. 195 °C: IR (KBr): 3040 (Ar-H), 2950,2860
(C-H): 1660 (C=O), 1600, 1550, 1500 (C=C), 1220 (asym. C-O-C): 1030 (sym. C-O-C):
Anal. (%) Calcd. for C38H38O6 (590.70): C, 77.26: H, 6.48. Found C, 77.12, H,6.26.
5i: Colourless (dioxane-ethanol: 80:20 v/v): yield 27%: m.p. 218 °C: IR (KBr): 3050
(Ar-H), 2900,2860 (C-H): 1660 (C=O), 1600, 1500 (C=C), 1250 (asym. C-O-C): 1040 (sym. C-
O-C): Anal. (%) Calcd. for C36H32O4Cl2 (599.54): C, 72.12: H, 5.38. Found C, 72.34, H,5.28.
General procedure for the preparation of 4’,4’’’-(polymethlenedioxy)
diacetophenones (4#a-c)
4-Hydroxyacetophenone (1) and α,ω-dibromoalkane (3 n= 2, 4 or 6) in the molar ratio
2:1 in acetone (100 mL) and anhydrous K2CO3 (0.025 mol) were refluxed (10 to 15 h).
The completion of the reaction was judged by the negative alcoholic ferric chloride test.
On completion of the reaction, acetone was distilled off and the residue was treated with
cold water (3 x 30 mL). The solid obtained on recrystallization from ethanol afforded

766
B. L. VERMA et al.
the compounds 4#a-c. Using this procedure following compounds were prepared.
4#a: Colourless: yield 67%: m.p. 161 °C: IR (KBr): 3060 (Ar-H), 2960, 2920, 2890 (C-
H): 1680 (C=O), 1600, 1510 (C=C), 1250 (asym. C-O-C): 1040 (sym. C-O-C): Anal. (%)
Calcd. for C18H18O4 (298.34): C, 72.41: H, 6.04. Found C, 72.15, H, 6.21.
4#b: Colourless: yield 70%: m.p. 141 °C: IR (KBr): 3080, 3040 (Ar-H), 2960,2870 (C-H):
1680 (C=O), 1600, 1580, 1510 (C=C), 1255 (asym. C-O-C): 1050 (sym. C-O-C): H NMR
1
(CDCl3) 2.01(m,4H,-(CH2)2-): 2.59 (s,6H,2 x -COCH3): 4.11 (m,4H, 2 x -OCH2-): 6.93-7.90
(m,8H,Ar-H). Anal. (%) Calcd. for C20H22O4 (326.40): C, 73.60: H, 6.79. Found C, 73.46, H, 6.50.
4#c: Colourless: yield 71%: m.p. 120 °C: IR (KBr): 3035 (Ar-H), 2950,2880 (C-H): 1670
(C=O), 1600, 1580, 1510 (C=C), 1240 (asym. C-O-C): 1010 (sym. C-O-C): H NMR (CDCl3)
1
1.30-2.10 (m,8H,-(CH2)4-): 2.58 (s,6H,2 x -COCH3): 4.04 (m, 4H, 2 x -OCH2-): 6.90-7.88
(m,8H,Ar-H): Anal. (%) Calcd. for C22H26O4 (354.39): C, 74.47: H, 6.08. Found C, 74.35, H, 7.15.
General procedure for the preparation of 4′,4′′′-(polymethylenedioxy) bis
substituted chalcones (5a-i) from compounds 4#a-c
Diacetophenone 4# (0.01 mol) and appropriate substituted aromatic aldehyde (0.025 mol)
were dissolved in ethanol (100 mL). To this solution NaOH (20 mL, 15%) was added and
the mixture was stirred constantly at room temperature (5 h), when a semi solid mass
separated. It was acidified with dilute HCl and separated solid was filtered, washed with
water (2 x 30 mL), dried and recrystallized from proper solvent to afford analytical samples
of (5a-i) in 60 to 80% yield and were fully characterized by m.p., m.m.p., co-TLC and super
imposable IR spectra with authentic samples prepared by another route.
General procedure for the preparation of 4’-{[4-(p-substituted phenoxy /
thiophenoxy)butyl]oxy} chalcones (6a-f)
Equimolar amount of appropriate 4’-[(4-bromo butyl)oxy]-chalcone (4d) and phenol / thiophenol
in dry acetone (100 mL) in the presence of anhydrous K2CO3 (0.25 mol) were refluxed (6-8 h).
The solvent was distilled and the residue in the flask was treated with ice cold water. The solid
separated was washed with 5% sodium hydroxide solution and finally with cold water (3 x 30 mL)
and dried. Recrystallization from ethanol / methanol gave analytical samples of compounds 6a-f.
6a: Colourless: yield 67%: m.p. 136 °C: IR (KBr): 3020 (Ar-H), 2980 (C-H): 1650
(C=O), 1600, 1590, 1510 (C=C), 1230 (asym. C-O-C): 1030 (sym. C-O-C): Anal. (%)
Calcd. for C25H24O3 (372.46): C, 80.62: H, 6.49. Found C, 80.20, H, 6.25.
6b: Colourless: yield 60%: m.p. 125 °C: IR (KBr): 3050 (Ar-H), 2910 (C-H): 1660
(C=O), 1600, 1580 (C=C), 1260 (asym. C-O-C): 1030 (sym. C-O-C): Anal. (%) Calcd. for
C25H23ClO3 (406.9): C, 73.79: H, 5.70.Found C, 73.51, H,5.56.
6c: Colourless: yield 65%: m.p. 115 °C: IR (KBr): 3010 (Ar-H), 2960 (C-H): 1650
(C=O), 1610, 1570 (C=C), 1240 (asym. C-O-C): 1050 (sym. C-O-C): Anal. (%) Calcd. for
C25H23BrO3 (451.35): C, 66.53: H, 5.14. Found C, 66.60, H, 5.20.
6d: Pale yellow: yield 58%: m.p. 114 °C: IR (KBr): 3060 (Ar-H), 2960, 2880 (C-H):
1650 (C=O), 1590, 1570, 1500 (C=C), 1250 (asym. C-O-C): 1030 (sym. C-O-C): Anal. (%)
Calcd. for C25H23NO5 (417.46): C, 71.93: H, 5.55. Found C, 71.40, H, 5.50.
6e: Colourless: yield 70%: m.p. 96 °C: IR (KBr): 3050 (Ar-H), 2900 (C-H): 1650
(C=O), 1610, 1580 (C=C), 1260 (asym. C-O-C): 1040 (sym. C-O-C): Anal. (%) Calcd. for
C25H24O2S (388.52): C, 77.28: H, 6.2. Found C, 77.50, H, 6.17.
6f: Cream colourless: yield 80%: m.p. 60 °C: IR (KBr): 3010 (Ar-H), 2960 (C-H):
1660 (C=O), 1600, 1570, 1500 (C=C), 1260 (asym. C-O-C): 1020 (sym. C-O-C): Anal. (%)
Calcd. for C25H23O2ClS (423.97): C, 70.99: H, 5.48.Found C, 70.60, H, 5.40.

Syntheses and Reactions of Substituted Chalcones
767
General procedure for the preparation of 3,3′-[poly methylene bis (oxy-o-
phenylene)] bis[5-(p-substituted phenyl)-2-pyrazolines] (7a-e)
To a solution of bis chalcone 5 (0.01 mol) in DMF (40 mL), hydrazine hydrate (0.2 mol, 95%)
was added drop wise. The reaction mixture was heated under reflux for 8-10 h. The contents
were poured into ice water with stirring. The resulting solid product was filtered, washed with
water and dried. Further purification was done by crystallization using suitable solvents.
7a: Colourless: (DMF-H2O:80:20 v/v): yield 75%.: m.p. 195 °C: IR (KBr) 3307(N-H), 3060
(Ar-H), 2930,2820 (C-H), 1620 (C=N), 1603,1590 (C=C), 1420 (CH2), 1260 (C-O-C asym.),
1030 (C-O-C sym).1H NMR (DMSO-d6, ppm) 3.00-3.20 and 3.40-3.60 (m, 4H, 2x-CH2- of
pyrazoline),5.60-5.78 (m, 2H, 2x-CH- of pyrazoline), 8.4 (s, 1H, NH), 6.80-7.80 (m, 18H, Ar-H),
4.45 (s , 4H, 2 x –OCH2-): Anal. (%) Calcd. for C32H30N4O2 (502.60): N, 11.15. Found N, 11.10.
7b: Colourless: DMF: yield 75%: m.p. 240 ° C: IR (KBr) 3310(N-H), 3040 (Ar-H), 2900,2850
(C-H), 1630 (C=N), 1590, 1510 (C=C), 1450 (CH2), 1250 (C-O-C asym.), 1080 (C-O-C sym).1H
NMR (DMSO-d6, ppm) 3.18-3.24 and 3.60-3.89 (m, 4H, 2x-CH2- of pyrazoline), 5.53-5.60 (m, 2H,
2x-CH- of pyrazoline), 8.9 (s, 1H, NH), 6.80-8.27 (m, 16H, Ar-H), 4.48 (s , 4H, 2 x –OCH2-),
3.85 (s, 6H, 2x -OCH3): Anal. (%) Calcd. for C34H34N4O4 (562.68): N, 9.95. Found N, 9.98.
Similarly other compounds 7c, yield 64%, m.p. 192 °C, 7d yield 66%, m.p. 180 °C and
7e, yield 68%, m.p. 200 °C were prepared in colourless crystalline form after recrystallization
of 7c and 7d with DMF-ethanol (80:20 v/v) mixture and 7e with DMF-H2O (80:20 v/v).
Results and Discussion
The synthesis of chalcones was effected via carbon-carbon bond formation using a Claisen-
Schmidt condensation reaction. p-Hydroxyacetophenone (1) was condensed with appropriate
aromatic aldehydes in equimolar ratio in presence of base at room temperature. The formation of
chalcones (α,β-unsaturated ketones) 2, was adjudged by the appearance of the carbonyl stretch at
1650-1670 cm-1 and disappearance of carbonyl stretch at 1683.8 cm-1 of p-hydroxyacetophenone.
The trans alkene (E-form) nature of these chalcones was judged by 1H NMR spectroscopy.
Compound 2 on refluxing with α,ω-dibromoalkanes (3, n= 2, 4 & 6) in equimolar ratio
in presence of dry acetone and anhydrous potassium carbonate resulted two products which
were separated by using ethanol. The ethanol soluble compound on purification was
analyzed as 4′-[(ω-bromoalkyl)oxy]-substituted chalcones (4a-i). The ethanol insoluble
compound was characterized as 4′,4′′′-(polymethylenedioxy) bis substituted chalcone (5a-i)
on the basis of its analysis and spectral results.
Synthesis of compounds (5a-i) was also carried out by another route.
p-Hydroxyacetophenone (1) was treated with α,ω-dibromoalkane (3, n= 2, 4 & 6) in the
molar ratio 2:1 in presence of acetone and anhydrous potassium carbonate. The reaction
mixture after usual workup afforded 4′,4′′′-(polymethylenedioxy)-diacetophenone (4#: n= 2,
4 & 6). Structure of these compounds was confirmed on the satisfactory elemental analysis
and spectroscopic data. The details have been given in experimental section. Base catalyzed
condensation of compounds (4# a, b & c) with different substituted aromatic aldehydes gave
bis chalcones (5a-i). Identity of these compounds obtained by different routes was
confirmed on basis of m.p., m.m.p., co-TLC and super imposable IR spectra.
Compound 4’-[(4-bromobutyl)oxy] chalcone (4d) on treatment with different p-substituted
phenols and thiophenols resulted compounds (6a-f) characterized as 4′-{[(4-(p-substituted
phenoxy / thiophenoxy)butyl]oxy} chalcones.
Finally compounds (5a, 5b, 5d, 5h and 5i) were treated with hydrazine hydrate in presence
of DMF afforded the corresponding bis-2-pyrazolines (7a-e). The analytical and spectral data of
synthesized compounds were in conformity with the proposed structure (Scheme 1).

O
O
(CH2)n
H
O
HO
R
HO
R
Br(CH2)n-Br
O
O
R
O
O
OH-/ EtOH
3
2a; R = H
(4# a-c)
b; R = OCH3
4# a, n=2;
(2 a-c)
1
c; R =Cl
b, n=4;
c, n=6
Br(CH2)n-Br
H
OH-/ EtOH
3
O
4, 5 a: R = H,
n =2
n =2
Br-(CH2)nO
R
b: R =OCH3,
R
O
O
(CH2)n
R
c: R = Cl,
d: R =H,
n =2
n =4
e: R =OCH3,
n =4
O
f: R =Cl,
g: R =H,
n =4
n =6
O
O
(5a-i)
(4a-i)
h: R = OCH3, n =6
i:
R =Cl,
n =6
NH2NH2.H2O / DMF
O
HX
R1
O
(CH2)n
X
O
H
(CH2)4
4d
R
R
R1
N
N
N
H
N
H
O
(7a-e)
6 a: R1 = H,
b: R1 =Cl,
X =O
X =O
X =O
7 a:
R = H,
n =2
(6 a-f)
b: R =OCH3, n =2
c: R1 = Br,
c: R = H,
d: R = Cl,
n =4
n =6
d: R1 = NO2, X =O
e: R1 = H,
X =S
X =S
e: R = OCH3, n =6
f: R1 = Cl,

Syntheses and Reactions of Substituted Chalcones
769
Conclusion
A convenient synthetic methodology for a new class of chalcones, bis chalcones and bis-
pyrazolines was described. It can be concluded that this class of compounds certainly holds
great promise towards the pursuit for further synthetic and biological evaluation.
Acknowledgments
The authors are thankful to the Head department of Chemistry, University College of
Science, M.L. Sukhadia University Udaipur-Rajasthan, for providing laboratory facilities.
Thanks are also due to M/S Sadier Research Laboratories Inc, Philodelphia (USA) and
Director CDRI Lucknow (UP) for elemental analysis and spectral data. One of us (RSS) is
also thankful to UGC for financial assistance.
References
1.
Dimmock J R, Elias D W, Beazely M A and Kandepu N M, Curr Med Chem., 1999,
6, 1125.
2.
3.
Go M L, Wu X and Liu X L, Curr Med Chem., 2005, 12, 483.
Ram V J, Saxena A S, Srivastava S and Chandra S, Bioorg Med Chem Lett.,
2000, 10, 2159.
4.
5.
Chen M, Theander T G, Chriestenson S B, Hviid L, Zhai L and Kharazmi A,
Antimicrob Agents Chemother, 1994, 38, 1470.
Chen M, Christensen S B, Zhai L, Rasmussen M H, Theander T G, Frokjaer S,
Steffensen S, Davidsen J and Kharazmi A, J Infect Dis., 1997, 176, 1327.
Azarifar D and Ghasemnejad H, Molecules, 2003, 8, 642.
Feldback Nielsen S, Baesen T, Larsen M, Schonning K and Kromann H, Bioorg Med
Chem., 2004, 12, 3047.
6.
7.
8.
9.
Jayamma Y, Sarangapani M and Reddy V M, Indian J Heterocyclic Chem., 1997,
74, 154.
Brazozoloski Z, Saczewski F and Gdaniec M, Eu J Med Chem., 2000, 35, 1053.
10. Singhal M, Jhala Y S, Dulawat S S and Verma B L, Indian J Heterocyclic Chem.,
2005, 14, 343.
11. Sukhwal S, Ashawa A and Verma B L, Asian J Chem., 1995, 7(3), 615.
12. Srivastava Y K, Sukhwal S, Ashawa A and Verma B L, J Indian Chem Soc., 1997,
74, 573.
13. Kothari S, Singhal M, Vijayvergiya D, Vyas R and Verma B L, J Indian Chem Soc.,
2000, 77, 329.
14. Sharma P, Hussain K F, Sukhwal S, Kothari S, Singhal M and Verma B L, Indian J
Chem., 1999, 38B, 966.
15. Bhandari R B, Sodani R S, Sharma P, Chundawat J S, Dulawat S S and Verma B L, J
Indian Chem Soc., 2006, 83,1113.
16. Sodani R S, Studies Related to Flavonoids, Ph.D. Thesis submitted to M. L. Sukhadia
University Udaipur (Raj.), India, 1983.

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