Synthesis and biological activity of novel tiliroside derivants

Article abstract of DOI:10.1016/j.ejmech.2011.07.059

A series of new tiliroside derivatives were synthesized and characterized by analytical ¹H NMR, ¹³C NMR and mass spectrometry. All of the compounds were evaluated for anti-diabetic properties in vitro using HepG2 cells. Compounds 3c, 3d, and 3i-l caused significant enhancements in glucose consumption by insulin-resistant HepG2 cells compared with control cells and cells that were exposed to metformin (an anti-diabetic drug). Moreover, compound 3l significantly activated adenosine 5′-monophosphate-activated protein kinase activity and reduced acetyl-CoA carboxylase activity. Thus, the tiliroside derivative 3l offers potential to be developed as a new approach for treating type II diabetes.

Full text of DOI:10.1016/j.ejmech.2011.07.059

European Journal of Medicinal Chemistry 46 (2011) 5189e5195
Contents lists available at ScienceDirect
European Journal of Medicinal Chemistry
journal homepage: http://www.elsevier.com/locate/ejmech
Short communication
Synthesis and biological activity of novel tiliroside derivants
,
c,
**
Nan Qin a, Chun-Bao Li b, Mei-Na Jin a, Li-Huan Shi c, Hong-Quan Duan a , Wen-Yan Niu
*
a Tianjin Medical University, Tianjin Key Laboratory on Technologies Enabling Development Clinical Therapeutics and Diagnostics, School of Pharmaceutical Sciences,
Research Center of Basic Medical Sciences, China
b Tianjin University, School of Science, China
c Tianjin Medical University, Department of Immunology, Key Laboratory of Immuno Microenvironment and Disease of the Educational Ministry of China, China
a r t i c l e i n f o
a b s t r a c t
A series of new tiliroside derivatives were synthesized and characterized by analytical 1H NMR, 13C NMR
and mass spectrometry. All of the compounds were evaluated for anti-diabetic properties in vitro using
HepG2 cells. Compounds 3c, 3d, and 3iel caused significant enhancements in glucose consumption by
insulin-resistant HepG2 cells compared with control cells and cells that were exposed to metformin (an
anti-diabetic drug). Moreover, compound 3l significantly activated adenosine 50-monophosphate-acti-
vated protein kinase activity and reduced acetyl-CoA carboxylase activity. Thus, the tiliroside derivative
3l offers potential to be developed as a new approach for treating type II diabetes.
Article history:
Received 18 January 2011
Received in revised form
18 July 2011
Accepted 31 July 2011
Available online 7 August 2011
Keywords:
Ó 2011 Elsevier Masson SAS. All rights reserved.
Acetyl-CoA carboxylase (ACC)
Adenosine 50-monophosphate-activated
protein kinase (AMPK)
Anti-diabetic
Tiliroside derivatives
1. Introduction
[6]. Our previous study suggested that tiliroside, isolated from
Potentilla chinensis, possessed significant anti-hyperglycemic
Diabetes mellitus comprises a group of chronic metabolic
disorders associated with the ability of the body to process
carbohydrates, fats and proteins [1]. Currently, approximately 3% of
the worldwide population is affected and global incidence is
increasing [1]. Noninsulin-dependent diabetes mellitus (type II
diabetes, T2D) is a heterogeneous disease characterized by hyper-
glycemia, which is caused by a disorder in insulin secretion, insulin
resistance (IR) in target tissues, and activation of the hepatic
glucose production pathway in the liver [2,3]. Amongst various
pathological effects, the failure of hepatic control of glucose
homeostasis is a key factor that causes hyperglycemia [4]. IR is
characterized by the failure of tissues to respond to insulin, which
results in reduced glucose intake in peripheral tissues and
increased hepatic glucose output [5].
effects compared with phenethyldiguanide in alloxan mice
(Patent no.: CN ZL200610015591.5) [7]. The kaempferol-3-O-b-D-
glucopyranose moiety of tiliroside shows only weak anti-diabetic
activity [8], and so the cinnamoyl moiety of tiliroside is presumed
to be the critical factor controlling its biological activity. In our
previous work, the cinnamoyl moiety of tiliroside was modified [9].
However, a pharmacokinetics study showed that most of the
tiliroside was quickly disintegrated into cinnamic acid and
kaempferol-3-O-glucoside, which in turn was decomposed into
kaempferol and glucose both in the blood and the intestines [10].
Based on these above observation, we designed a series of novel
tiliroside derivatives, which could replace the glucose group and
were connected to kaempferol by its CH2 group (Fig. 1).
HepG2 cells are hepatocellular carcinoma cells that are valuable
for investigating liver-associated functions. They maintain most
functions of the liver and are stable during many passages [11,12]. IR
in liver cells principally causes impaired glycogen synthesis and
fails to suppress glucose production, which is the major contrib-
uting factor leading to hyperglycemia [13]. Numerous previous
studies have used IR HepG2 cell to investigate T2D [14e17].
Adenosine 50-monophosphate-activated protein kinase (AMPK)
is considered to be a cellular energy sensor. It is important to
understand the mechanism by which hepatic AMPK coordinates
hepatic energy metabolism, as AMPK is a key master switch in
In recent years, plant extracts have been identified as a new
avenue to explore for novel anti-diabetic drugs. Due to undesirable
side effects associated with existing drugs, an increasing number of
patients demand to use natural products with anti-diabetic activity
* Corresponding author. Tel.: þ86 22 23542018; fax: þ86 22 23542775.
** Corresponding author. Tel.: þ86 138 205 126 49; fax: þ86 22 2783 3287.
E-mail addresses: duanhq@tijmu.edu.cn (H.-Q. Duan), wniu@tijmu.edu.cn
(W.-Y. Niu).
0223-5234/$ e see front matter Ó 2011 Elsevier Masson SAS. All rights reserved.
doi:10.1016/j.ejmech.2011.07.059

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N. Qin et al. / European Journal of Medicinal Chemistry 46 (2011) 5189e5195
Fig. 1. The modifications of tiliroside.
regulating glucose and lipid metabolism in the liver [17,18]. Many
flavonoids are reported to increase AMPK phosphorylation [19e21].
This present study concerns the synthesis of novel tiliroside
derivatives, the study of their structureeactivity relationships, and
the potential anti-diabetic mechanism of these compounds on
AMPK activity in human HepG2 hepatocytes.
reaction from the 2 compounds and kaempferol. The structures of
compounds 3aew were determined by 1H, 13C NMR, and 2D NMR
spectral data analyses, including COSY, HSQC, HMBC, and ROESY
spectra.
3. Pharmacology
2. Chemistry
3.1. Glucose consumption assays in IR HepG2 cells
The target compounds were synthesized through three steps
(Scheme 1). The first step was a ClassineSchimitt reaction from the
substituted benzaldehyde to the a,b-unsaturated keto. Then the a-
hydrogen atom in this keto was substituted by a bromine atom.
Human HepG2 cells were cultured in high-glucose DMEM
supplemented with 10% fetal bovine serum. After achieving
confluence, cells were cultured in 96-well cluster plates in the same
medium for 24 h, before they were treated with 10ꢀ7 M insulin for
36 h in serum-free and phenol red-free high-glucose DMEM. After
Finally, the 3 compounds were prepared by the etherification
Scheme 1. The synthesis of target compounds.

N. Qin et al. / European Journal of Medicinal Chemistry 46 (2011) 5189e5195
5191
this incubation, the cells were washed four times with high-glucose
DMEM (pH 4) and twice with phosphate-buffered saline. The cells
were added to serum-free and phenol red-free high-glucose DMEM
containing the various test compounds at different concentrations.
The cells were incubated for 24 h, and then glucose content in the
culture medium was measured using a glucose assay kit to assess
the effects of the test compounds on glucose consumption by IR
HepG2 cells. The enhancement ratio of glucose consumption (GC)
was calculated as follows: GC % ¼ (GC treatment group ꢀ GC of
model group)/GC of model group ꢁ 100. The potencies of the
products were expressed as median effective concentration (EC50
)
values [13,22].
3.2. Western blotting
Human HepG2 cells were grown in 12-well plates. Cells were
lysed on ice with 200 l RIPA buffer (100 mM NaCl, 0.25% w/v
m
sodium deoxycholate, 1.0% w/v NP40, 0.1% w/v sodium dodecyl
sulfate (SDS), 2 mM ethylenediaminetetraacetic acid, 50 mM NaF,
10 nM okadaic acid, 1 mM sodium orthovanadate, protease inhib-
itor cocktail and 50 mM TriseHCl, pH 7.2). Samples were electro-
phoresed on 7.5% SDS-polyacrylamide gels, and transferred to
polyvinylidene fluoride membranes. The membranes were blocked
for 1 h with 5% (w/v) bovine serum albumin, and incubated with
the primary antibodies overnight at 4 ꢂC, followed by incubation
with appropriate secondary antibodies for 1 h at room temperature.
Immunoblots were detected with chemiluminescent reagent and
autoradiographic film.
4. Results
4.1. Glucose consumption in IR HepG2 cells
Fig. 2. Compound 3l phosphorylates AMPK and ACC in human HepG2 cells. Results are
the means ꢃ SE of 3 independent experiments. *p < 0.05 vs. basal.
All test compounds were assayed for their effects on glucose
consumption by IR HepG2 cells and potencies were compared using
EC50 values. Compounds 3aed, 3hel, 3n and 3p significantly
enhanced glucose consumption by IR HepG2 cells. Compounds 3c,
3d, and 3iel had greater anti-diabetic activity than the marketed
anti-diabetic drug metformin (Table 1).
5. Discussion
Most of the novel tiliroside derivants in this present study (the 3
series of compounds) at low concentrations improved glucose
consumption by IR HepG2 cells. However, when the size of the
substituted group (R1) was significantly larger than OCH2CH3 or the
R2 was not an H atom, the activity of the compound was much lower,
such as was the case for compounds 3e, 3f, 3g, 3r, 3s, 3u and 3v. In
addition, the activities of compounds with OCH2CH3, OCH3 and CN
substituted groups were greater than the OH group. Thus, we
hypothesized that the amino residue of the binding site in the target
protein may be a hydrophobic residue, and that the pocket is unable
to hold groups larger than OCH2CH3. We also suggest that the
4.2. Western blotting assay
Western blotting analysis was use to evaluate the potential anti-
diabetic mechanism of compound 3l. Human HepG2 cells were
treated with increasing doses of compound 3l for 2 h. Compound 3l
stimulated the phosphorylation of AMPK and acetyl-CoA carbox-
ylase (ACC) markedly in a dose-dependent fashion (Fig. 2). These
results suggest that AMPK and ACC may be the key molecules in the
signal transduction pathway that are targeted by compound 3l.
unsaturated group (CN group) potentially provides a pep interaction
with the binding site, since compound 3l displayed excellent activity.
Current research is focused on preventing or treating diabetes
mellitus using substances present in natural products found in the
diet or fruits. Flavonoids are ubiquitous components in vegetables
and fruits, and are often consumed in large quantities during the
daily diet. Many anti-diabetic flavonoids have been reported,
including isoprenylated flavonoids from Erythrina mildbraedii that
inhibit protein tyrosine phosphatase-1B with 50% inhibitory
Table 1
Effects on glucose consumption of compounds 3 in IR HepG2 cells.
Compound EC50 (mM) Compound EC50 (mM) Compound EC50 (mM)
3a
3b
3c
3d
3e
3f
3g
3h
3i
0.368
0.658
0.149
0.042
>20
>20
>20
0.473
0.010
3j
3k
3l
3m
3n
3o
3p
3q
0.015
0.013
0.003
>20
0.669
1.075
0.393
>20
3r
3s
3t
3u
5.070
6.190
>20
3.555
2.587
>20
concentration (IC50) values ranging from 14.8 to 39.7 mM [23]; 6-
hydroxyluteolin, hypolaetin and quercetagetin inhibit dephos-
phorylated glycogenphosphorylasewith IC50 values of 11.6,15.7, and
3v
3w
Metformin
Tiliroside
0.270
0.155
9.7
production from various gluconeogenic substrates in perifused rat
hepatocytes at concentrations as low as 10 M [25]. However, these
mM, respectively [24]; and silibinin, which lowers glucose
m

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N. Qin et al. / European Journal of Medicinal Chemistry 46 (2011) 5189e5195
flavonoids show only weak activity compared with marketed anti-
diabetic drugs. Our previous study demonstrated that tiliroside,
isolated as a principal compound from P. chinensis extracts, dis-
played beneficial effects on hyperlipidemia due to diabetes, and
showed significant anti-hyperglycemic, anti-hyperlipidemic, anti-
oxidant activities in diabetic animals [26]. The novel tiliroside
skeleton in compounds 3c, 3d and 3iel produced and described in
this present study have significant anti-diabetic activities, with EC50
by thin-layer chromatography (TLC) using pre-coated silica gel
aluminum plates containing a fluorescence indicator. 1H, 13C NMR
spectra were taken using a Bruker AV400 MHz. Chemical shifts of
1H NMR spectra were recorded in parts per million with respect to
tetramethylsilane (TMS), and the coupling constants (J) were
measured in Hz. Data are reported as follows: chemical shift,
multiplicity (s ¼ singlet, d ¼ doublet, t ¼ triplet, q ¼ quartet,
m ¼ multiplet). 1H NMR spectra were recorded in CDCl3 and DMSO-
d6 using TMS as internal standard. Mass spectra were taken in ESI
mode on an Agilent 1200 LC-MS (Agilent, Palo Alto, CA, USA). The
preparation of compounds 1aew and 2aew were in accordance
with previous reports [38,39].
values ranging from 0.003 to 0.149
potency to metformin (Table 1).
mM that are comparable in
AMPK is an energy sensor that regulates cellular metabolism
that activates ACC [27]. In addition, AMPK is involved in the glucose
metabolism of various tissues, including the liver, skeletal muscle,
adipose tissues, and pancreatic
b
cells: which are key tissues in the
7.2. General procedure for the synthesis of compounds 3
pathogenesis of T2D [28]. The activation of AMPK in skeletal
muscle, liver, and adipose tissues enhances metabolism, glucose
uptake, insulin sensitivity, and oxidative metabolism of fatty acids,
as well as increases in glucose transport and glycolysis. Thus, by
inhibiting hepatic glucose output and increasing the liver stores of
glucose due to causing its conversion to glycogen, AMPK could
control systemic blood glucose levels in the body [29]. Therefore,
a defect in AMPK signaling could account for many of the abnor-
malities observed in IR related to T2D [30].
To a mixture of kaempferol (1.2 eq) and K2CO3 (1.2 eq) in 1,4-
dioxane (10 ml), which was stirred for 90 min while maintaining
gentle reflux, was added a solution of the 2 compounds (1 eq) in
1,4-dioxane (5 ml) for 30 min. The reaction mixture was refluxed
until the starting material disappeared, as indicated by TLC
(CH2Cl2:MeOH, 95:5). The solvent was removed from the reaction
mixture under reduced pressure. Water was added, the aqueous
phase was neutralized (to pH 7) with 1 M HCl, and then extracted
with ethyl acetate. The organic phase was dried over anhydrous
magnesium sulfate, filtered and concentrated. The crude product
was purified using a gel-permeation chromatograph (HW-40;
CH2Cl2:MeOH, 1:1) and prepared-TLC to give a yellow solid product.
As for the actions of flavonoid analogs in the AMPK signal
transduction pathway, luteolin enhances the phosphorylation of
AMPK and ACC at 10 and 20
[31]. The synthetic flavonoid S17834 persistently stimulates AMPK
phosphorylation and activity at 10 M in HepG2 cells [32],
kaempferol and kaempferol-3-O-glucoside weakly enhance AMPK
activity at 10 M in 3T3-L1 cells [33], while naringenin increases
muscle cell glucose uptake via AMPK at 75 M [34]. In addition, 7-
mM in HepG2 cell lines, respectively
m
7.2.1. 3-O-[(E)-4-(4-Hydroxyphenyl)-2-oxobut-3-en-1-yl]
m
kaempferol (3a)
m
Yield 18.5%. 1H NMR (400 MHz, DMSO-d6):
d 12.56 (1H, s, OH),
O-methylaromadendrin, isolated from Inula viscose, stimulates the
reactivation of insulin-mediated phosphorylation of AMPK in
10.27 (1H, br s, OH), 10.12 (1H, br s, OH), 8.05 (2H, d, J ¼ 8.9 Hz), 7.59
(1H, d, J ¼ 16.1 Hz), 7.52 (2H, d, J ¼ 8.6 Hz), 6.92 (2H, d, J ¼ 8.9 Hz),
6.84 (1H, d, J ¼ 16.1 Hz), 6.81 (2H, d, J ¼ 8.6 Hz), 6.47 (1H, d,
J ¼ 2.1 Hz), 6.22 (1H, d, J ¼ 2.0 Hz), 5.02 (2H, s). 13C NMR (100 MHz,
HepG2 cells at 10
In a doseeresponse experiment (1
g/ml), compound 3l not only activated AMPK but it also
mM [35].
mg/ml [2.2 mM], 2 mg/ml and
5
m
DMSO-d6): d 194.6, 178.0, 164.7, 161.6, 160.7, 156.8, 155.7, 143.6,
increased the phosphorylation of ACC (Fig. 2) at lower doses
compared with each of the flavonoids mentioned above. Further-
more, in a previous report by our investigational team [36], we
demonstrated that compound 3l increased surface GLUT4myc
levels and markedly stimulated the phosphorylation of AMPK and
ACC in C2C12 and L6 muscle cells. Thus, compound 3l with its novel
skeleton could activate the AMPK signal pathway in three different
cell lines, implicating a combination of downstream multi-target
proteins in AMPK pathway.
The results in this present study suggest that tiliroside deriva-
tives may be promising candidates in the development of new anti-
diabetic lead compounds, and further biological evaluations are
underway in our laboratory.
136.8, 131.2, 131.0, 125.6, 121.0, 119.3, 116.4, 116.0, 104.5, 99.1, 94.2,
75.6, 60.2. ESI-MS m/z: 445.3 [M ꢀ H]ꢀ.
7.2.2. 3-O-[(E)-4-(4-(Benzyloxy)phenyl)-2-oxobut-3-en-1-yl]
kaempferol (3b)
Yield21.3%.1HNMR(400MHz, DMSO-d6):
d12.57 (1H, s, OH),10.90
(1H, br s, OH), 10.28 (1H, br s, OH), 8.05 (2H, d, J ¼ 8.9 Hz), 7.65e7.61
(3H, m), 7.47e7.39 (4H, m), 7.34 (1H, m), 7.07 (2H, d, J ¼ 8.9 Hz), 6.94
(2H, m), 6.92 (1H, d, J ¼ 16.2 Hz), 6.47 (1H, d, J ¼ 2.0 Hz), 6.22 (1H, d,
J ¼ 2.0 Hz), 5.16 (2H, s), 5.04 (2H, s). 13C NMR (100 MHz, DMSO-d6):
d
194.7, 178.0, 164.7, 161.6, 161.0, 160.7, 156.8, 155.7, 143.0, 137.1, 136.8,
131.0, 130.9, 128.9, 128.4, 128.3, 127.4, 121.0, 120.5, 116.0, 115.8, 104.5,
99.1, 94.2, 75.6, 69.9. ESI-MS m/z: 535.5 [M ꢀ H]ꢀ.
6. Conclusion
7.2.3. 3-O-[(E)-4-(4-Methoxyphenyl)-2-oxobut-3-en-1-yl]
kaempferol (3c)
In summary, a novel series of tiliroside derivatives were
synthesized. Among them compounds 3c, 3d and 3iel had signif-
icant anti-diabetic activities compared with the marketed anti-
diabetic drug metformin [37]. Compound 3l significantly acti-
vated AMPK activity, reduced ACC activity and enhanced glucose
consumption in IR HepG2 cells.
Yield 19.2%. 1H NMR (400 MHz, DMSO-d6):
d 12.57 (1H, s, OH),
10.89 (1H, br s, OH),10.29 (1H, br s, OH), 8.05 (2H, d, J ¼ 8.9 Hz), 7.63
(1H, d, J ¼ 16.4 Hz), 7.63 (2H, d, J ¼ 8.8 Hz), 6.98 (2H, d, J ¼ 8.8 Hz),
6.92 (2H, d, J ¼ 8.9 Hz), 6.91 (1H, d, J ¼ 16.4 Hz), 6.46 (1H, d,
J ¼ 2.0 Hz), 6.22 (1H, d, J ¼ 2.0 Hz), 5.04 (2H, s), 3.80 (3H, s). 13C NMR
(100 MHz, DMSO-d6): d 194.7, 178.0, 164.7, 161.9, 161.6, 160.7, 156.8,
155.7, 143.1, 136.7, 131.0, 127.2, 121.0, 120.3, 116.0, 114.9, 104.5, 99.1,
7. Experimental protocols
94.2, 75.6, 55.8. ESI-MS m/z: 459.3 [M ꢀ H]ꢀ.
7.1. Chemistry
7.2.4. 3-O-[(E)-4-(4-Ethoxyphenyl)-2-oxobut-3-en-1-yl]
kaempferol (3d)
All solvents and reagents were obtained from commercial
Yield 17.3%. 1H NMR (400 MHz, DMSO-d6):
d
12.57 (1H, s, OH),
sources and used without purification. Reactions were monitored
10.90 (1H, s, OH), 10.28 (1H, s, OH), 8.05 (2H, d, J ¼ 8.7 Hz), 7.63 (1H,

N. Qin et al. / European Journal of Medicinal Chemistry 46 (2011) 5189e5195
5193
d, J ¼ 16.5 Hz), 7.61 (2H, d, J ¼ 8.5 Hz), 7.29 (2H, d, J ¼ 8.0 Hz), 6.97
7.2.10. 3-O-[(E)-4-(4-Isopropylphenyl)-2-oxobut-3-en-1-yl]
(2H, d, J ¼ 8.7 Hz), 6.93 (2H, d, J ¼ 8.5 Hz), 6.90 (1H, d, J ¼ 16.5 Hz),
6.47 (1H, d, J ¼ 1.5 Hz), 6.22 (1H, d, J ¼ 1.5 Hz), 5.04 (2H, s), 4.07 (2H,
q, J ¼ 6.9 Hz), 1.34 (3H, t, J ¼ 6.9 Hz). 13C NMR (100 MHz, DMSO-d6):
kaempferol (3j)
Yield 21.2%. 1H NMR (400 MHz, DMSO-d6):
d
12.55 (1H, s, OH),
8.05 (1H, d, J ¼ 8.9 Hz), 7.64 (1H, d, J ¼ 16.3 Hz), 7.59 (2H, d,
J ¼ 8.2 Hz), 7.30 (2H, d, J ¼ 8.2 Hz), 7.00 (1H, d, J ¼ 16.3 Hz), 6.93 (2H,
d, J ¼ 8.9 Hz), 6.47 (1H, d, J ¼ 2.0 Hz), 6.22 (1H, d, J ¼ 2.0 Hz), 5.06
(2H, s), 2.91 (1H, sept, J ¼ 6.9 Hz), 1.20 (6H, d, J ¼ 6.9 Hz). 13C NMR
d
194.2, 177.5, 164.2, 161.1, 160.7, 160.2, 156.3, 155.2, 142.6, 136.3,
130.5, 130.4, 126.5, 121.1, 120.5, 119.7, 115.5, 114.8, 104.0, 98.6, 93.7,
75.2, 63.3, 14.5. ESI-MS m/z: 473.4 [M ꢀ H]ꢀ.
(100 MHz, DMSO-d6): d 194.9, 178.0, 164.7, 161.6, 160.7, 156.8, 155.7,
7.2.5. 3-O-[(E)-4-(4-Butoxyphenyl)-2-oxobut-3-en-1-yl]
152.0, 143.2, 136.7, 132.3, 132.0, 131.0, 129.2, 127.4, 126.6, 116.0,
kaempferol (3e)
104.5, 99.1, 94.2, 75.7, 60.2, 33.9, 24.0. ESI-MS m/z: 471.2 [M ꢀ H]ꢀ.
Yield 16.2%. 1H NMR (400 MHz, DMSO-d6):
d 12.57 (1H, s, OH),
10.89 (1H, s, OH), 10.29 (1H, s, OH), 8.05 (2H, d, J ¼ 8.8 Hz), 7.63 (1H,
d, J ¼ 16.9 Hz), 7.61 (2H, d, J ¼ 8.2 Hz), 6.97 (2H, d, J ¼ 8.8 Hz), 6.93
(2H, d, J ¼ 8.2 Hz), 6.90 (1H, d, J ¼ 16.9 Hz), 6.47 (1H, br s), 6.22 (1H,
br s), 5.04 (2H, s), 4.07 (2H, t, J ¼ 6.4 Hz), 1.73e1.66 (2H, m),
1.48e1.39 (2H, m), 0.93 (3H, t, J ¼ 7.4 Hz). 13C NMR (100 MHz,
7.2.11. 3-O-[(E)-4-(4-(tert-Butyl)phenyl)-2-oxobut-3-en-1-yl]
kaempferol (3k)
Yield 17.3%. 1H NMR (400 MHz, DMSO-d6):
d 12.55 (1H, s, OH),
10.84 (1H, s, OH), 10.25 (1H, s, OH), 8.06 (2H, d, J ¼ 8.8 Hz), 7.65 (1H,
d, J ¼ 16.3 Hz), 7.60 (2H, d, J ¼ 8.4 Hz), 7.46 (2H, d, J ¼ 8.4 Hz), 7.00
(1H, d, J ¼ 16.3 Hz), 6.93 (2H, d, J ¼ 8.8 Hz), 6.47 (1H, d, J ¼ 2.2 Hz),
6.22 (1H, d, J ¼ 2.0 Hz), 5.07 (2H, s), 1.29 (9H, s). 13C NMR (100 MHz,
DMSO-d6):
d 194.2, 177.5, 164.2, 161.1, 160.9, 160.2, 156.3, 155.2,
142.6, 136.3, 130.5, 130.4, 126.5, 120.5, 119.7, 115.5, 114.9, 104.0, 98.6,
93.7, 75.1, 67.4, 30.6, 18.7, 13.6. ESI-MS m/z: 501.5 [M ꢀ H]ꢀ.
DMSO-d6) d 194.9, 178.0, 164.7, 161.6, 160.7, 156.8, 155.7, 154.2, 143.1,
136.8, 132.0, 131.0, 128.9, 126.3, 122.0, 121.0, 116.0, 104.5, 99.1, 94.2,
7.2.6. 3-O-[(E)-4-(4-4-(Hexyloxy)phenyl)-2-oxobut-3-en-1-yl]
75.7, 35.1, 31.3. ESI-MS m/z: 485.2 [M ꢀ H]ꢀ.
kaempferol (3f)
Yield 20.1%. 1H NMR (400 MHz, DMSO-d6):
d
12.57 (1H, s, OH),
7.2.12. 3-O-[(E)-4-(4-Cyanophenyl)-2-oxobut-3-en-1-yl]
10.89 (1H, s, OH), 10.27 (1H, s, OH), 8.05 (2H, d, J ¼ 8.4 Hz), 7.63 (1H,
d, J ¼ 16.9 Hz), 7.61 (2H, d, J ¼ 8.4 Hz), 6.97 (2H, d, J ¼ 8.4 Hz), 6.93
(2H, d, J ¼ 8.4 Hz), 6.90 (1H, d, J ¼ 16.9 Hz), 6.47 (1H, s), 6.22 (1H, s),
5.03 (2H, s), 4.00 (2H, t, J ¼ 6.4 Hz), 1.73e1.68 (2H, m), 1.42e1.39
(2H, m), 1.31e1.30 (4H, m), 0.93 (3H, t, J ¼ 6.7 Hz). 13C NMR
kaempferol (3l)
Yield 20.1%. 1H NMR (400 MHz, DMSO-d6):
d 12.53 (1H, s, OH),
10.89 (1H, s, OH), 10.25 (1H, s, OH), 8.04 (2H, d, J ¼ 8.9 Hz),
7.91e7.86 (4H, m), 7.70 (1H, d, J ¼ 16.4 Hz), 7.19 (1H, d, J ¼ 16.4 Hz),
6.91 (2H, J ¼ 8.9 Hz), 6.47 (1H, d, J ¼ 2.0 Hz), 6.22 (1H, d, J ¼ 2.0 Hz),
(100 MHz, DMSO-d6):
d
194.2, 177.5, 164.2, 161.1, 160.9, 160.2, 156.3,
5.10 (2H, s). 13C NMR (100 MHz, DMSO-d6)
d 195.0, 177.9, 167.6,
155.2, 142.6, 136.3, 130.5, 130.4, 126.5, 120.5, 119.7, 115.5, 114.9,
104.0, 98.6, 93.7, 75.1, 67.6, 30.9, 28.5, 25.1, 22.0, 13.6. ESI-MS m/z:
529.6 [M ꢀ H]ꢀ.
164.7, 163.5, 161.6, 160.7, 159.0, 156.8, 155.7, 142.4, 140.8, 139.3,
136.7, 133.2, 133.1, 131.0, 129.6, 126.0, 121.0, 119.0, 116.0, 112.9, 104.5,
99.2, 94.2, 75.9. ESI-MS m/z: 453.9 [M ꢀ H]ꢀ.
7.2.7. 3-O-[(E)-4-(4-4-(Octyloxy)phenyl)-2-oxobut-3-en-1-yl]
7.2.13. 3-O-[(E)-2-Oxo-4-(4-(trifluoromethyl)phenyl)but-3-en-1-
yl] kaempferol (3m)
kaempferol (3g)
Yield 19.7%. 1H NMR (400 MHz, DMSO-d6):
d
12.57 (1H, s, OH),
Yield 22.4%. 1H NMR (400 MHz, DMSO-d6):
d 12.53 (1H, s, OH),
10.90 (1H, s, OH), 10.28 (1H, s, OH), 8.05 (2H, d, J ¼ 8.8 Hz), 7.63 (1H,
d, J ¼ 16.9 Hz), 7.61 (2H, d, J ¼ 8.2 Hz), 6.97 (2H, d, J ¼ 8.8 Hz), 6.93
(2H, d, J ¼ 8.2 Hz), 6.90 (1H, d, J ¼ 16.9 Hz), 6.47 (1H, br s), 6.22 (1H,
br s), 5.04 (2H, s), 4.00 (2H, t J ¼ 7.0 Hz), 1.72e1.69 (2H, m),
1.39e1.38 (2H, m), 1.30e1.22 (8H, m), 0.93 (3H, t, J ¼ 6.8 Hz). 13C
10.89 (1H, s, OH), 10.25 (1H, s, OH), 8.04 (2H, d, J ¼ 8.8 Hz), 7.90 (2H,
d, J ¼ 8.3 Hz), 7.79 (2H, d, J ¼ 8.3 Hz), 7.74 (1H, d, J ¼ 16.3 Hz), 7.18
(1H, d, J ¼ 16.3 Hz), 6.92 (2H, d, J ¼ 8.8 Hz), 6.48 (1H, d, J ¼ 2.0 Hz),
6.22 (1H, d, J ¼ 2.0 Hz), 5.10 (2H, s). 13C NMR (100 MHz, DMSO-d6):
d
195.0, 177.9, 167.4, 164.7, 161.6, 160.7, 156.8, 155.7, 141.1, 138.8,
NMR (100 MHz, DMSO-d6):
d
194.2, 177.5, 164.2, 161.1, 160.9, 160.2,
136.7, 132.2, 132.0, 131.0, 129.6, 129.1, 126.3, 125.4, 121.0, 116.0,
156.3, 155.2, 142.7, 136.3, 130.5, 130.4, 126.5, 120.5, 119.7, 115.5,
114.9, 104.0, 98.6, 93.7, 90.65, 75.1, 69.9, 67.6, 65.1, 62.7, 31.2, 28.7,
28.6, 28.5, 25.4, 22.1, 13.9. ESI-MS m/z: 557.6 [M ꢀ H]ꢀ.
104.5, 99.2, 94.2, 75.8, 71.6. ESI-MS m/z: 497.0 [M ꢀ H]ꢀ.
7.2.14. 3-O-[(E)-4-(4-Fluorophenyl)-2-oxobut-3-en-1-yl]
kaempferol (3n)
7.2.8. 3-O-[(E)-(2-Oxo-4-phenylbut-3-en-1-yl)] kaempferol (3h)
Yield 19.2%. 1H NMR (400 MHz, DMSO-d6):
d 12.54 (1H, s, OH),
Yield 17.6%. 1H NMR (400 MHz, DMSO-d6):
d
12.56 (1H, s, OH),
10.36 (1H, br s, OH), 10.00 (1H, br s, OH), 8.03 (2H, d, J ¼ 8.4 Hz),
7.75e7.65 (3H, m), 7.29e7.25 (2H, m), 7.00 (1H, d, J ¼ 16.0 Hz), 6.93
(2H, d, J ¼ 8.4 Hz), 6.50 (1H, br s), 6.24 (1H, br s), 5.06 (2H, s). 13C
10.89 (1H, s, OH), 10.27 (1H, s, OH), 8.05 (2H, d, J ¼ 8.8 Hz), 7.67 (1H,
d, J ¼ 16.4 Hz), 7.69e7.67 (2H, m), 7.45e7.43 (3H, m), 7.05 (1H, d,
J ¼ 16.4 Hz), 6.93 (2H, d, J ¼ 8.8 Hz), 6.47 (1H, d, J ¼ 1.9 Hz), 6.22 (1H,
NMR (100 MHz, DMSO-d6)
d 194.9, 177.9, 165.1, 164.9, 162.7, 161.6,
d, J ¼ 1.9 Hz), 5.08 (2H, s). 13C NMR (100 MHz, DMSO-d6):
d
194.9,
160.8, 156.8, 155.7, 141.9, 136.7, 131.4, 131.3, 131.0, 130.4, 122.8, 121.0,
116.6, 116.4, 116.0, 104.5, 99.2, 94.3, 75.7, 63.3. ESI-MS m/z: 447.1
[M ꢀ H]ꢀ.
178.0, 164.7, 161.6, 160.7, 156.8, 155.7, 143.1, 136.8, 134.7, 131.2, 131.0,
129.4, 129.0, 122.8, 121.0, 116.0, 104.5, 99.1, 94.2, 75.7. ESI-MS m/z:
429.4 [M ꢀ H]ꢀ.
7.2.15. 3-O-[(E)-4-(4-Chlorophenyl)-2-oxobut-3-en-1-yl]
7.2.9. 3-O-[(E)-(2-Oxo-4-(p-tolyl)but-3-en-1-yl)] kaempferol (3i)
kaempferol (3o)
Yield 13.4%. 1H NMR (400 MHz, DMSO-d6):
d
12.56 (1H, s, OH),
Yield 12.4%. 1H NMR (400 MHz, DMSO-d6):
d 12.60 (1H, s, OH),
10.88 (1H, br s, OH),10.27 (1H, br s, OH), 8.05 (2H, d, J ¼ 8.9 Hz), 7.63
(1H, d, J ¼ 16.3 Hz), 7.57 (1H, d, J ¼ 8.0 Hz), 7.25 (2H, d, J ¼ 8.0 Hz),
6.99 (1H, d, J ¼ 16.3 Hz), 6.92 (2H, d, J ¼ 8.9 Hz), 6.47 (1H, d,
J ¼ 2.0 Hz), 6.22 (1H, d, J ¼ 2.0 Hz), 5.06 (2H, s), 2.34 (3H, s). 13C NMR
10.97 (1H, br s, OH), 10.34 (1H, br s, OH), 8.10 (2H, d, J ¼ 8.9 Hz), 7.76
(2H, d, J ¼ 8.5 Hz), 7.71 (1H, d, J ¼ 16.4 Hz), 7.55 (2H, d, J ¼ 8.5 Hz),
7.12 (1H, d, J ¼ 16.4 Hz), 6.97 (2H, d, J ¼ 8.9 Hz), 6.53 (1H, d,
J ¼ 2.0 Hz), 6.27 (1H, d, J ¼ 2.0 Hz), 5.13 (2H, s). 13C NMR (100 MHz,
(100 MHz, DMSO-d6):
d
194.9, 178.0, 164.7, 161.6, 160.7, 156.8, 155.7,
DMSO-d6): d 194.9, 178.0, 164.7, 161.6, 160.7, 156.8, 155.7, 141.7,
143.2, 141.3, 136.8, 132.0, 131.9, 131.0, 129.1, 121.8, 121.0, 116.0, 104.5,
136.7, 135.7, 133.7, 131.0, 130.7, 129.5, 123.5, 121.0, 116.0, 104.5, 99.2,
99.1, 94.2, 75.7, 21.5. ESI-MS m/z: 443.4 [M ꢀ H]ꢀ.
94.2, 75.8, 63.3. ESI-MS m/z: 463.8 [M ꢀ H]ꢀ.

5194
N. Qin et al. / European Journal of Medicinal Chemistry 46 (2011) 5189e5195
7.2.16. 3-O-[(E)-4-(4-Bromophenyl)-2-oxobut-3-en-1-yl]
7.2.22. 3-O-[(E)-4-(3,4-Dichlorophenyl)-2-oxobut-3-en-1-yl]
kaempferol (3p)
kaempferol (3v)
Yield 13.1%. 1H NMR (400 MHz, DMSO-d6):
d
12.53 (1H, s, OH),
Yield 24.5%. 1H NMR (400 MHz, DMSO-d6):
d 12.54 (1H, s, OH),
10.87 (1H, s, OH), 10.25 (1H, s, OH), 8.04 (2H, d, J ¼ 8.7 Hz), 7.63 (4H,
m), 7.07 (1H, d, J ¼ 16.3 Hz), 6.92 (2H, d, J ¼ 8.7 Hz), 6.47 (1H, d,
J ¼ 1.5 Hz), 6.22 (1H, d, J ¼ 1.5 Hz), 5.07 (2H, s). 13C NMR (100 MHz,
10.90 (1H, s, OH), 10.26 (1H, s, OH), 8.05 (2H, d, J ¼ 8.6 Hz), 8.02 (1H,
br s), 7.69 (2H, m), 7.63 (1H, d, J ¼ 16.3 Hz), 7.15 (1H, d, J ¼ 16.3 Hz),
6.91 (2H, d, J ¼ 8.6 Hz), 6.47 (1H, br s), 6.22 (1H, br s), 5.08 (2H, s).
DMSO-d6):
d
194.9,177.9,164.7,161.6,160.7,156.8, 155.7,141.7,136.7,
13C NMR (100 MHz, DMSO-d6):
d 194.4, 177.4, 170.3, 164.2, 161.1,
134.0, 132.4, 131.0, 130.9, 124.5, 123.6, 121.0, 116.0, 104.5, 99.2, 94.2.
160.2, 156.3, 155.2, 139.7, 136.2, 135.1, 132.8, 131.8, 131.0, 130.5,
130.2, 128.3, 124.3, 120.5, 115.5, 112.8, 104.0, 98.6, 93.7, 75.3, 59.7.
ESI-MS m/z: 498.3 [M ꢀ H]ꢀ.
ESI-MS m/z: 507.6 [M ꢀ H]ꢀ.
7.2.17. 3-O-[(E)-4-(4-(Methylthio)phenyl)-2-oxobut-3-en-1-yl]
kaempferol (3q)
7.2.23. 3-O-[(E)-4-(3-Bromo-4-methoxyphenyl)-2-oxobut-3-en-1-
Yield 16.5%. 1H NMR (400 MHz, DMSO-d6):
d
12.56 (1H, s, OH),
yl] kaempferol (3w)
10.90 (1H, s, OH), 10.28 (1H, s, OH), 8.05 (2H, d, J ¼ 8.8 Hz), 7.63 (1H,
d, J ¼ 16.0 Hz), 7.61 (2H, d, J ¼ 8.0 Hz), 7.29 (2H, d, J ¼ 8.0 Hz), 7.00
(1H, d, J ¼ 16.0 Hz), 6.93 (2H, d, J ¼ 8.8 Hz), 6.47 (1H, br s), 6.22 (1H,
br s), 5.06 (2H, s), 2.51 (3H, s). 13C NMR (100 MHz, DMSO-d6):
Yield 19.5%. 1H NMR (400 MHz, DMSO-d6):
d 12.61 (1H, s, OH),
10.93 (1H, br s, OH), 10.32 (1H, br s, OH), 8.10 (2H, d, J ¼ 8.8 Hz),
8.02 (1H, s), 7.74 (1H, d, J ¼ 8.8 Hz), 7.64 (1H, d, J ¼ 16.4 Hz), 7.21
(1H, d, J ¼ 8.8 Hz), 7.04 (1H, d, J ¼ 16.4 Hz), 6.96 (2H, d, J ¼ 8.8 Hz),
6.52 (1H, br s), 6.26 (1H, br s), 5.10 (2H, s), 3.95 (3H, s). 13C NMR
d
194.3, 177.5, 164.2, 161.1, 160.2, 156.3, 155.2, 142.2, 136.3, 130.5,
130.4, 129.0, 125.5, 121.1, 120.5, 115.5, 104.0, 98.6, 93.7, 75.2, 14.1.
(100 MHz, DMSO-d6): d 194.1, 177.5, 164.2, 161.1, 160.2, 157.1, 156.3,
ESI-MS m/z: 475.5 [M ꢀ H]ꢀ.
155.1, 141.0, 136.2, 132.8, 130.5, 129.9, 128.6, 128.3, 121.3, 120.5,
115.5, 112.8, 111.2, 104.0, 98.6, 93.7, 75.2, 56.5. ESI-MS m/z: 538.2
[M ꢀ H]ꢀ.
7.2.18. 3-O-[(E)-4-(3-Hydroxy-4-methoxyphenyl)-2-oxobut-3-en-
1-yl] kaempferol (3r)
Yield 12.4%. 1H NMR (400 MHz, DMSO-d6):
d 12.57 (1H, s, OH),
References
10.89 (1H, s, OH), 10.27 (1H, s, OH), 9.25 (1H, s, OH), 8.05 (2H, d,
J ¼ 8.4 Hz), 7.55 (1H, d, J ¼ 16.0 Hz), 7.12 (2H, m), 6.97 (1H, d,
J ¼ 8.4 Hz), 6.92 (2H, d, J ¼ 8.4 Hz), 6.82 (1H, d, J ¼ 16.0 Hz), 6.47 (1H,
br s), 6.22 (1H, br s), 5.02 (2H, s), 3.82 (3H, s). 13C NMR (100 MHz,
[1] J.P. Boyle, A.A. Honeycutt, K.M. Narayan, T.J. Hoerger, L.S. Geiss, H. Chen,
T.J. Thompson, Diabetes Care 24 (2001) 1936e1940.
[2] R.A. DeFronzo, R.C. Bonadonna, E. Ferrannini, Diabetes Care 15 (1992)
318e368.
DMSO-d6):
d 194.1, 177.5, 164.2, 161.1, 160.2, 156.3, 155.2, 150.4,
[3] W.T. Cefalu, Exp. Biol. Med. 226 (2001) 13e26.
[4] S.P. Kim, M. Ellmerer, G.W. Van Citters, R.N. Bergman, Diabetes 52 (2003)
2453e2460.
[5] S. Dinneen, J. Gerich, R. Rizza, N. Engl. J. Med. 327 (1992) 707e713.
[6] N. Kawahara, M. Satake, Y. Goda, Chem. Pharm. Bull. 50 (2002)
1619e1620.
[7] C. Zhao, W. Qiao, Y.W. Zhang, B. Lu, H.Q. Duan, J. Chin. Mater. Med. 33 (2008)
680e682.
[8] E. Sousa, L. Zanatta, I. Seifriz, T.B. Creczynski-Pasa, M.G. Pizzolatti,
B. Szpoganicz, F.R.M.B. Silva, J. Nat. Prod. 67 (2004) 829e832.
[9] Y.J. Zhu, Y.W. Zhang, Y. Liu, H.W. Chu, H.Q. Duan, Molecules 15 (2010)
9174e9183.
[10] Y. Qi, C. Tang, H.Q. Duan, Drug Eval. Res. 36 (2010) 187e190.
[11] B. Kola, A.B. Grossman, M. Korbonits, Obesity Metabolism Front Horm Res..
Karger, Basel, 2008, 198e211
[12] N.B. Javit, FASEB. J. 4 (1990) 163e168.
[13] W.D. Xie, W. Wang, H. Su, D.M. Xing, Y. Pan, L.J. Du, Comp. Biochem. Physiol. C:
Toxicol. Pharmacol. 143 (2006) 429e435.
[14] K. Nakamaru, K. Matsumoto, T. Taguchi, M. Suefuji, Y. Murata, M. Igata,
J. Kawashima, T. Kondo, H. Motoshima, K. Tsuruzoe, N. Miyamura,
K. Toyonaga, E. Araki, Biochem. Biophys. Res. Commun. 328 (2005) 449e454.
[15] C.L. Lin, J.K. Lin, Mol. Nutr. Food Res. 52 (2008) 930e939.
[16] Z. Luo, Y. Zhang, F. Li, J. He, H. Ding, L. Yan, H. Cheng, Endocrine 36 (2009)
60e69.
[17] C.L. Lin, H.C. Huang, J.K. Lin, J. Lipid Res. 48 (2007) 2334e2343.
[18] S.I. Ben, K. Laurent, A. Loubat, S. Giorgetti-Peralad, P. Colosetti, P. Auberger,
J.F. Tanti, Y. Le Marchand-Brustel, F. Bost, Oncogene 27 (2008) 3576e3586.
[19] J. Ahn, H. Lee, S. Kim, J. Park, T. Ha, Biochem. Biophys. Res. Commun. 373
(2008) 545e549.
[20] P.B. Martínez de Morentin, C.R. González, M. López, J. Pathol. 222 (2010)
329e334.
[21] J. Lu, D.M. Wu, Y.L. Zheng, B. Hu, Z.F. Zhang, Q. Shan, Z.H. Zheng, C.M. Liu,
Y.J. Wang, J. Pathol. 222 (2010) 199e212.
[22] C.G. Li, G. Ning, J.L. Chen, Chin. J. Diabetes 7 (1999) 198e200.
[23] M.K. Na, J.P. Jang, D. Njamen, J.T. Mbafor, Z.T. Fomum, B.Y. Kim, W.K. Oh,
J.S. Ahn, J. Nat. Prod. 69 (2006) 1572e1576.
[24] A. Kato, N. Nasu, K. Takebayashi, I. Adachi, Y. Minami, F. Sanae, N. Asano,
A.A. Watson, R.J. Nash, J. Agric. Food Chem. 56 (2008) 4469e4473.
[25] D. Detaille, C. Sanchez, N. Sanz, J.M. Lopez-Novoa, X. Leverve, M.Y. El-Mir, Life
Sci. 82 (2008) 1070e1076.
146.7, 143.1, 136.3, 130.5, 127.0, 121.8, 120.5, 119.7, 115.5, 114.2, 112.0,
104.0, 98.6, 93.7, 75.1, 55.6. ESI-MS m/z: 475.4 [M ꢀ H]ꢀ.
7.2.19. 3-O-[(E)-4-(3-Methoxy-4-hydroxyphenyl)-2-oxobut-3-en-
1-yl] kaempferol (3s)
Yield 13.5%. 1H NMR (400 MHz, DMSO-d6):
d 12.58 (1H, s, OH),
10.89 (1H, s, OH), 10.26 (1H, s, OH), 9.70 (1H, br s, OH), 8.06 (2H, d,
J ¼ 8.8 Hz), 7.59 (1H, d, J ¼ 16.1 Hz), 7.30(1H, d, J ¼ 1.5 Hz), 7.13 (1H, dd,
J ¼ 8.2, 1.5 Hz), 6.92 (2H, d, J ¼ 8.8 Hz), 6.90 (1H, d, J ¼ 16.1 Hz), 6.47
(1H, d, J ¼ 2.0 Hz), 6.22 (1H, d, J ¼ 2.0 Hz), 5.04 (2H, s), 3.82 (3H, s).13C
NMR (100 MHz, DMSO-d6):
d 194.5, 178.0, 164.7, 161.6, 160.7, 156.8,
155.7, 150.2, 148.4, 144.0, 136.8, 131.0, 126.2, 124.0, 121.0, 119.7, 116.1,
116.0, 112.0, 104.5, 99.1, 94.2, 75.5, 56.1. ESI-MS m/z: 475.4 [M ꢀ H]ꢀ.
7.2.20. 3-O-[(E)-4-(3-Methoxy-4-benzyloxy phenyl)-2-oxobut-3-
en-1-yl] kaempferol (3t)
Yield 22.5%. 1H NMR (400 MHz, DMSO-d6):
d 12.58 (1H, s, OH),
10.90 (1H, s, OH), 10.27 (1H, s, OH), 8.06 (2H, d, J ¼ 8.0 Hz), 7.62 (1H,
d, J ¼ 16.2 Hz), 7.46e7.7.35 (6H, m), 7.23 (1H, d, J ¼ 8.4 Hz), 7.09 (1H,
d, J ¼ 8.4 Hz), 6.97 (1H, d, J ¼ 16.2 Hz), 6.92 (2H, d, J ¼ 8.0 Hz), 6.47
(1H, br s), 6.22 (1H, br s), 5.14 (2H, s), 5.07 (2H, s), 3.82 (3H, s). 13C
NMR (100 MHz, DMSO-d6):
d 194.1, 177.5, 164.2, 161.1, 160.2, 156.3,
155.2, 150.2, 149.2, 143.0, 136.6, 136.3, 130.5, 128.4, 127.9, 127.2,
123.2, 120.5, 115.5, 113.1, 110.8, 104.0, 98.6, 93.7, 75.0, 69.8, 55.6. ESI-
MS m/z: 565.5 [M ꢀ H]ꢀ.
7.2.21. 3-O-[(E)-4-(3-Hydroxy-4-chlorophenyl)-2-oxobut-3-en-1-
yl] kaempferol (3u)
Yield 13.5%. 1H NMR (400 MHz, DMSO-d6):
d 12.57 (1H, s, OH),
10.89 (2H, s, OH), 10.28 (1H, s, OH), 8.06 (2H, d, J ¼ 8.6 Hz), 7.75 (1H,
s), 7.58 (1H, d, J ¼ 16.2 Hz), 7.50 (1H, d, J ¼ 8.5 Hz), 7.02 (1H, d,
J ¼ 8.5 Hz), 6.93 (2H, d, J ¼ 8.6 Hz), 6.92 (1H, d, J ¼ 16.2 Hz), 6.48 (1H,
br s), 6.22 (1H, br s), 5.04 (2H, s). 13C NMR (100 MHz, DMSO-d6):
[26] W. Qiao, C. Zhao, N. Qin, H.Y. Zhai, H.Q. Duan, J. Ethnopharmacol. 135 (2011)
515e521.
[27] D.G. Hadie, D. Carling, A.T.R. Sim, Trends Biochem. Sci. 14 (1989) 20e23.
[28] Y.C. Long, J.R. Zierath, J. Clin. Invest. 116 (2006) 1776e1783.
[29] P. Misra, R. Chakrabarti, Indian J. Med. Res. 125 (2007) 389e398.
[30] M.C. Towler, D.G. Hardie, Circ. Res. 16 (2007) 328e341.
[31] J.F. Liu, Y. Ma, Y. Wang, Z.Y. Du, J.K. Shen, H.L. Peng, Phytother. Res. 25 (2011)
588e596.
d
194.1, 177.5, 164.2, 161.1, 160.2, 156.3, 155.5, 155.2, 141.6, 136.2,
130.5,130.3,128.8,126.5,120.5,120.4,120.3,116.9,115.5,104.0, 98.6,
93.7, 75.1. ESI-MS m/z: 479.9 [M ꢀ H]ꢀ.

N. Qin et al. / European Journal of Medicinal Chemistry 46 (2011) 5189e5195
5195
[32] M.W. Zang, S.Q. Xu, K.A. Maitland-Toolan, A. Zuccollo, X.Y. Hou, B.B. Jiang,
M. Wierzbicki, T.J. Verbeuren, R.A. Cohen, Diabetes 55 (2006) 2180e2191.
[33] D.T. Ha, T.N. Trung, T.T. Phuong, N. Yim, Q.C. Chen, K.H. Bae, Bioorg. Med.
Chem. Lett. 20 (2010) 6076e6081.
[36] L.H. Shi, N. Qin, L.J. Hu, L.J. Liu, H.Q. Duan, W.Y. Niu, Diabetes. Res. Clin. Pract.
92 (2011) e41ee46.
[37] Flavonoid derivatives, synthesis and their medicinal purpose, patent PCT-
CN2010-001818.
[34] K. Zygmunt, B. Faubert, J. MacNeil, E. Tsiani, Biochem. Biophys. Res. Commun.
398 (2010) 178e183.
[38] J. Tatsuzaki, K.F. Bastow, K. Nakagawa-Goto, S. Nakamura, H. Itokawa, K.H. Lee,
J. Nat. Prod. 69 (2006) 1445e1449.
[35] W.Y. Zhang, J.J. Lee, I.S. Kim, Y. Kim, J.S. Park, C.S. Myung, Biol. Pharm. Bull. 33
(2010) 1494e1499.
[39] K.S. Babu, X.C. Li, M.R. Jacob, Q.F. Zhang, S.I. Khan, D. Ferreira, A.M. Clark,
J. Med. Chem. 49 (2006) 7877e7886.