Bioorganic & Medicinal Chemistry Letters 22 (2012) 154–163

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Bioorganic & Medicinal Chemistry Letters

journal homepage: www.elsevier .com/ locate/bmcl

Discovery of estrogen receptor a modulators from natural compoundsin Si-Wu-Tang series decoctions using estrogen-responsive MCF-7breast cancer cells

Li Liu, Hongyue Ma ⇑, Yuping Tang, Wenxing Chen, Yin Lu, Jianming Guo, Jin-ao Duan ⇑Jiangsu Key Laboratory for TCM Formulae Research, Nanjing University of Chinese Medicine, Xianlin Road 138#, Nanjing 210046, China

a r t i c l e i n f o

Article history:Received 23 August 2011Revised 25 October 2011Accepted 11 November 2011Available online 18 November 2011

Keywords:SERMsSi-Wu-Tang series decoctionsFlexX-Pharm

0960-894X/$ - see front matter � 2011 Elsevier Ltd.doi:10.1016/j.bmcl.2011.11.041

Abbreviations: ER-a, estrogen receptor a; SWT, Sestrogen receptor modulators; ER, estrogen receptor;Chinese medicine; ERE, estrogen regulatory element;2-yl)-2, 5-diphenyltetrazolium bromide; DMSO, dbovine serum; MEM, eagle’s minimal essential mediuMVD, Molegro Virtual Docker; RMSD, Root Mean Squ⇑ Corresponding authors. Tel.: +86 25 85811916; fa

E-mail addresses: hongyuema@163.com (H. Ma), d

a b s t r a c t

The binding between the estrogen receptor a (ER-a) and a variety of compounds in traditional Chineseformulae, Si-Wu-Tang (SWT) series decoctions, was studied using a stably-transfected human breast can-cer cell line (MVLN). In 38 compounds tested from SWT series decoctions, the estrogen-like activity of 22compounds was above 60% in 20 lg mL�1. Furthermore, theoretical affinity of these compounds was cer-tificated using the functional virtual screen of ER-a modulators by FlexX-Pharm. The accuracy of func-tional virtual screening of ER-a modulators could reach to 77.27%. The results showed that somecompounds, such as organic acids and flavones in SWT series decoctions could be used as selective estro-gen receptor modulators (SERMs) and could be selected for further development as potential agents forestrogen related diseases.

� 2011 Elsevier Ltd. All rights reserved.

There has been a growing movement in the development of non-steroidal estrogens that modulate estrogen receptor (ER) function.These nonsteroidal ER ligands are referred to as selective estrogenreceptor modulators (SERMs).1 The major forces driving the devel-opment of new SERMs as therapeutic agents in ER biology are as fol-lows: first, SERMs have better receptor selectivity than steroidalligands, such as estradiol (E2); second, they produce a higher tis-sue-selectivity than steroidal ligands; and third, they are moreadaptable to structural modification that may result in increasedpotency and better pharmacokinetic and pharmacologic proper-ties.2,3 Current research on SERMs for uses related to menopausestrives for developing a SERM, which would relieve menopausalvasomotor and vaginal symptoms, prevent fractures, and have atleast neutral cardiovascular effects, without stimulating the breastor endometrium. Presently available data indicate that SERMs arealso being investigated for indications in men.4 Bazedoxifene,raloxifene and lasofoxifene as SERMs have been developed. Baze-doxifene was approved for the treatment of postmenopausal osteo-porosis in women at increased risk of fracture in Europe in 2009,and is under regulatory review in the United States. Raloxifene is

All rights reserved.

i-Wu-Tang; SERMs, selectiveE2, estradiol; TCM, traditionalMTT, 3-(4,5-dimethythiazol-

imethylsulfoxide; FBS, fetalm; RLU, relative light units;

are Deviation; MD, MolDock.x: +86 25 85811916.ja@njutcm.edu.cn (J. Duan).

indicated for the treatment and prevention of osteoporosis in post-menopausal women in the United States and Europe. Lasofoxifenehas been studied on the postmenopausal evaluation and risk-reduc-tion. However, arzoxifene as a SERM has been discontinued becauseof so many side effects.4

Natural product extracts are normally used directly as herbaltherapies to treat illnesses. The search for new therapeutic SERMsusually starts with its extracts that show some medicinal property,such as traditional Chinese medicine (TCM) which has been widelyused in China, Asia and other parts of the world for several thou-sand years.

In China, Si-Wu-Tang (SWT) decoction and its series decoctions(Xiang-Fu-Si-Wu decoction, Tao-Hong-Si-Wu decoction, Qing-Lian-Si-Wu decoction, Shao-Fu-Zhu-Yu decoction5,6) are widelyused in clinical practice for treating gynecology blood stasis syn-drome, such as primary dysmenorrhea, climacteric syndrome,breast cancer and other estrogen related diseases.7 A more recentstudy has demonstrated that the SWT decoction can be integratedas an alternative therapy within Western medicine.8

In this Letter, we studied a class of compounds including organ-ic acids (1–8), flavones (9–18), alkaloids (19–23), lactones (24–27)and others (28–38) in Si-Wu-Tang (SWT) series decoctions for theirpossible SERM-like properties by using cellular model in which theestrogenic action could be detected by bioluminescence. Molecularstructures of the compounds studied were shown in Table 1. MCF-7 cells are derived from human breast cancer tissue and predomi-nantly contain ER-a.9,10 This model is a stably-transfected MCF-7cell line (MVLN cell line, a bioluminescent MCF-7-derived cell line

L. Liu et al. / Bioorg. Med. Chem. Lett. 22 (2012) 154–163 155

to study the modulation of estrogenic activity) with a reportergene which allows expression of the firefly luciferase enzyme un-der control of the estrogen regulatory element (ERE) of the Xeno-pus vitellogenin A2 gene in front of a thymidine kinase

Table 1Molecular structures of the compounds studied

No. Compounds

Organic acids

1 Vanillic acid

2 Gallic acid

3 Isoferulic acid

4 Ferulic acid

5 Caffeic acid

6 Coumaric acid

7 Protocatechuic acid

8 Cinnamic acid

Flavones

9 Quercetin

10 Baicalein

11 Kaempferol

promoter.11–14 If the compounds were estrogen-like compounds,they would interact with the ER-a and increase the luciferaseinduction in MVLN cells. In contrast, luciferase induction decreasesif they possess antiestrogenic activity. These studies would provide

Molecular structures

O

OH

OH

O CH3

OHOH

HO

O OH

OH

OCH3

O

HO

OCH3

HO O

OH

HO

HO

O

OH

OHO

HO

OH

OHO

HO

O

OH

OHOOH

HO O

OHOH

OOHHO

HO O

OHOOH

HO O

OH

(continued on next page)

Table 1 (continued)

No. Compounds Molecular structures

12 Hydroxysafflor yellow A OH

O

OOH

OHOH

HO

HO

OHO

OHHO

HO

OHO

OH

13 WogoninO

OOH

OH3C

HO

14 Rutin

OOOH

HO O

OHOH

O

OHOH

OH

OO

H3C

HO

OH

OH

15 Isorhamnetin-3-o-nehesperridin

OOH

O

OH

HO

O

OCH3

O

OHOHOH

O

O

CH3OH

OHOH

16 Isorhamnetin-3-o-glucose(6-1) rhamnose

OOOH

HO O

OCH3OH

O

OHOH

OH

OO

H3C

HO

OH

OH

17 Baicalin

OOH

O O

HO

O

OHHO

HO

O

OH

156 L. Liu et al. / Bioorg. Med. Chem. Lett. 22 (2012) 154–163

Table 1 (continued)

No. Compounds Molecular structures

18 Scutellarin

O

OH O

OH

HO

O

O

O OH

HO

HOOH

Alkaloids

19 Tetrahydropulmatine

NO

O

OO

CH3

CH3

H3C

H3C

20 Palmatine hydrochloride

N+OOCH3 CH3

OH3C

OCH3

Cl-

21 Berberine

N+O

O

OO

Cl-H3C

H3C

22 Jatrorrhizine chloride

N+O

O

OOH

Cl-H3C

H3C

CH3

23 Ligustrazine hydrochloride

N

N CH3

CH3H3C

H3CHCl

Lactones

24 Dehydro-a-curcumeneO

CH2

H2C

O

CH2

25 Alantolactone

O

CH3

CH3

CH2

O

26 Costunolide

CH3

OO

CH2

H

H

CH3

(continued on next page)

L. Liu et al. / Bioorg. Med. Chem. Lett. 22 (2012) 154–163 157

Table 1 (continued)

No. Compounds Molecular structures

27 Isoalantolactone

O

CH2

H

CH2

O

H

H

H

Others

28 Linoleic acid

CH3

O

OH

29 Anisole

OCH3

30 Aucubin

O

O

O

OHHO

HO

H

H

OH

OH

OH

31 Albiflorin

OHO

HOOH

OH

O OCH3

OH

OOO

32 Cinnamaldehyde

O

33 Columbianadin

O OO

OO

H3C CH3

H3CCH3

34 Catalpol

O

OH

OH

H

OOO

OHHOOH

OHHO

158 L. Liu et al. / Bioorg. Med. Chem. Lett. 22 (2012) 154–163

Table 2Effect of compounds studied on ERE luciferase enzyme

No. Compounds E2 induction* (%)

100 lg mL�1 20 lg mL�1

Organic acids1 Vanillic acid 98.61 113.512 Gallic acid 63.71 92.193 Isoferulic acid 55.65 75.784 Ferulic acid 75.42 60.455 Caffeic acid 20.00 24.736 Coumaric acid 25.95 22.917 Protocatechuic acid 55.14 14.918 Cinnamic acid 25.95 12.00

Flavones9 Quercetin 76.81 70.0010 Baicalein 71.77 48.4411 Kaempferol 38.56 45.1512 Hydroxysafflor yellow A 39.55 45.2813 Wogonin 37.30 36.3614 Rutin 107.97 90.8315 Isorhamnetin-3-o-nehesperridin 55.77 88.3016 Isorhamnetin-3-o-glucose(6-1) rhamnose 83.65 84.0417 Baicalin 45.20 71.7018 Scutellarin 50.28 53.46

Alkaloids19 Tetrahydropulmatine 118.84 95.0020 Palmatine hydrochloride 46.89 64.7821 Berberine 51.41 58.4922 Jatrorrhizine chloride 71.19 52.2023 Ligustrazine hydrochloride 40.68 39.18

Lactones24 Dehydro-a-curcumene 41.95 42.5425 Alantolactone 47.03 40.3026 Costunolide 50.42 39.1827 Isoalantolactone 34.75 34.70

Others28 Linoleic acid 234.78 141.6729 Anisole 91.35 100.0030 Aucubin 81.25 99.10

Table 2 (continued)

No. Compounds E2 induction* (%)

100 lg mL�1 20 lg mL�1

31 Albiflorin 78.47 87.3932 Cinnamaldehyde 1.61 79.6933 Columbianadin 73.39 79.6934 Catalpol 54.03 75.7835 Anisaldehyde 48.59 74.2136 Peoniflorin 70.16 71.8837 a-Cyperone 51.41 64.7838 Benzaldehyde 2.78 62.16

* Induction potency: (RLUx/RLU control)/(RLUE2/RLU control) � 100.

Table 1 (continued)

No. Compounds Molecular structures

35 Anisaldehyde

O

OCH3

36 Peoniflorin

OO

O

O

OOO

OHOH

OHO

HO

OH

CH3

37 a-Cyperone

CH3O

CH3

CH2

H3C

38 Benzaldehyde

O

L. Liu et al. / Bioorg. Med. Chem. Lett. 22 (2012) 154–163 159

evidence of the potential biologic importance of the compounds ofSi-Wu-Tang (SWT) series decoctions in the treatment of estrogenrelated diseases. These studies would also provide potential SERMsand choices for hormone replacement therapy.

Sodium pyruvate, penicillin, streptomycin, trypsin, 3-(4,5-dim-ethythiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) anddimethylsulfoxide (DMSO) were purchased from Sigma AldrichCo. (St. Louis, MO, USA). Fetal bovine serum (FBS), eagle’s minimalessential medium (MEM), and MEM without phenol red were fromGibco Co. (Grand Island, NY, USA). Luciferase assay system E1500and G418 were provided by Promega Co. (St. Wisconsin, WI,USA). The compounds studied and E2 were purchased from Na-tional Institute for the Control of Pharmaceutical and BiologicalProducts, China.

MVLN cell line was kindly provided by Pro. Ting-xia Dong fromthe Hong Kong University of Science and Technology. Cells weremaintained in MEM supplemented with 10% FBS, penicillin(50 U mL�1), streptomycin (50 lg mL�1), HEPES (10 mM), NaHCO3

(0.5 g L�1), Amino acid (0.1 mM) and Sodium pyruvate (1.0 mM)at 37 �C under 5% CO2. We harvested confluent cells in 25 cm2 plas-tic Corning flasks with trypsin–EDTA (0.05/0.02%). The trypsin wasneutralized by 10% MEM–FBS.

Table 3Theoretical affinity of compounds (% E2 induction 20 lg mL�1 >60%) with respect to ER-a

No. Compounds MDscore

Hbond

Number of hydrogenbonds

Interacting residues

Organic acids1 Vanillic acid �72.2 �0.9 2 Arg394, Leu387, Leu391, Met388, Phe4042 Gallic acid �72.8 �6.9 4 His524, Leu346, Leu525,Thr3473 Isoferulic acid �81.8 �6 3 Ala350, Leu391, Leu387, Leu346, Phe404, Thr3474 Ferulic acid �72.8 �5.3 2 Arg394, Leu387, Leu391, Met388, Phe404

Flavones9 Quercetin �76.3 �4.8 2 Gly521, His524, Ile424, Leu346, Leu384, Leu387, Leu391, Met38814 Rutin �87.2 2.7 1 Glu353, His524, Leu346, Leu349, Leu391, Leu428, Thr34715 Isorhamnetin-3-o-nehesperridin �114.7 �15.4 4 Gly521, His524, Ile424, Leu346, Leu384, Leu387, Leu391, Phe404, Thr347,

Ala35016 Isorhamnetin-3-o-glucose(6-1)

rhamnose�145.7 �8.7 9 Ala350, Gly521, His524, Leu346, Leu387, Leu540, Met388, Phe404

17 Baicalin �79.3 �6.4 1 His524, Ile424, Leu346, Leu525, Phe425

Alkaloids19 Tetrahydropulmatine �9.4 �2.5 3 His524, Leu346, Leu387, Met388, Met42120 Palmatine hydrochloride �36.8 �0.5 1 Glu353, His524, Leu346, Leu391, Leu525, Met388, Phe404

Others28 Linoleic acid �103.7 �2.5 1 His524, Leu346, Leu384, Leu391, Met388, Phe40429 Anisole 58.6 �0.2 2 Arg394, Glu353, Met388, Phe40430 Aucubin �121.1 �11.7 6 Ala350, Glu353, Gly521, His524, Leu346, Leu384, Leu391, Leu525,

Met38831 Albiflorin �76.7 �9.4 3 Ala350, Leu346, Leu349, Leu384, Leu38732 Cinnamaldehyde �69.4 �2.5 0 His52433 Columbianadin �114 �2.8 2 Ala350, His524, Leu346, Leu384, Leu387, Leu391, Leu525, Met388,

Phe404, Gly52134 Catalpol �93.7 �16.4 9 Ala350, Arg394, Glu353, Leu346, Leu384, Leu387, Leu391, Leu525,

Phe40435 Anisaldehyde �16.3 �2.3 2 Ala350, His524, Leu525, Thr34736 Peoniflorin 3915.11 �0.6 2 Glu353, Leu346, Leu384, Leu391, Leu525, Leu540, Met388, Met421,

Phe40437 a-Cyperone �61.7 �2.5 1 Leu346, Leu387, Leu525, Phe40438 Benzaldehyde �60.9 �2.5 2 Arg394, Glu353, Leu391, Met388

160 L. Liu et al. / Bioorg. Med. Chem. Lett. 22 (2012) 154–163

Three days before the experiments, MCF-7 cells were culturedin MEM without phenol red and supplemented with 2% Charcoal/Dextran treated FBS. Cells were seeded (1 � 104 cells/well) in 96well plates. After 24 h, cells were treated with the different con-centrations (20 lg mL�1, 100 lg mL�1) of compounds or 0.1 lME2 for 24 h. The control cells were maintained in the absence ofany compound or exposed to 0.1 lM E2 for 24 h. At the end ofthe incubation, each well was injected with luminescence buffer.Then the culture media was removed and the cells were washedextensively with cold PBS (pH 7.4) for twice. The cells were dis-rupted by the 40 lL lysis buffer. Then 20 lL lysis buffer was re-moved into another 96 well plate. The corresponding luciferaseactivity was determined by GloMax 96 Luminometer (Promega,U.S.A). The protein concentration of each sample was determinedby 10 lL lysis buffer using BCA Protein Assay kit.

Induced light was expressed in relative light units (RLU). Proteincontent of each extract was measured and RLU were expressed permg protein. Estrogenic activity of compounds was expressed inpercentage of E2-induced luciferase (100%).

We used the X-ray crystal structures of E2 (PDB codes 1GWR)15

as the potent estrogen receptor a (ER-a) inducer16 as the basis ofthe docking experiment. Compounds were drawn by using ISIS-Draw and then exported formats for the mol. The two-dimensionalstructures were converted to three dimensions by small molecule-line structure transformation services. The three dimensions wereadded hydrogen atoms and charges schemes with Open Babel andexported in mol2 format for further study of molecular docking.

Molegro Virtual Docker (MVD) is based on a differential evolutionalgorithm; the solution of the algorithm takes into account the sumof the intermolecular interaction energy between the ligand and theprotein, and the intramolecular interaction energy of the ligand. It

could be accurately forecast the active sites of protein moleculesbased ligands. MVD is a precise semi-flexible molecular docking pro-gram. By increasing the qualifications, the recognition accuracy ofbonding models is enhanced. Compared with other dock software,the accuracy of MVD (http://www.molegro.com/products.php) ishigher. (MVD: 87%, Glide: 82%, Surflex: 75%, FlexX: 58%).

The crystal structure of 1GWR was used as the basis of the dock-ing experiments. The active sites exploited in docking studies weredefined as a subset region of 10.0 Å radiuses from the centroid ofthe ligand E2. Before screening, the docking protocol was validated.E2 was docked into the binding pocket to obtain the docked poseand the RMSD (Root Mean Square Deviation) of all atoms betweenthese two conformations was at <1.00 Å indicating that the param-eters for docking simulation were good in reproducing the X-raycrystal structure.

Generally, between 10 and 100 individual docking simulationswere performed, and every possible docking model was analyzedby MolDock (MD) scores and hydrogen bonds. After multiple dock-ing simulations, consistent docking models among the best-fittedmodels were used for the development of the hypotheses.

Statistical calculations were carried out with Microsoft Excel2003. Results were expressed as the mean ± S.D. of six independentexperiments.

Current studies in our laboratories concern the ER-a, the impor-tance of which is now well recognized in the development andtreatment of breast cancer and other estrogen related diseases. Ithas been reported that SERMs belong to different classes of com-pounds, such as isoflavonoids, lignans, coumestans, etc. Chemicalstructures alone are, however, not sufficient to predict estrogenicactivity. To screen SERMs as a ‘natural’ alternative to estrogen,we compared the action of a series of compounds in SWT series

Figure 1. Binding mode of compounds (% E2 induction 20 lg mL�1 >60%) (green) when docked into the X-ray crystal structure of ER-a (red). The number of each compound inthe manuscript was marked in the upper left corner (white).

L. Liu et al. / Bioorg. Med. Chem. Lett. 22 (2012) 154–163 161

decoctions which widely used in clinical practice for the estrogenrelated diseases on the MCF-7 human breast cancer cell linethrough estrogenic response. The results were shown in Table 2.

In organic acids compounds group (1-8), vanillic acid (1), gallicacid (2), isoferulic acid (3) and ferulic acid (4) showed high estro-genic activity (>60% in 20 lg mL�1), however, caffeic acid (5), cou-maric acid (6), protocatechuic acid (7) and cinnamic acid (8)showed low estrogenic activity (<30% in 20 lg mL�1). It illustratedthat OCH3 group on the benzene ring was responsible for the estro-gen-like activity of the organic acids compounds. It also illustratedthat more OH groups in the benzene ring would increase the activity.

In flavonoids compounds group (9–18), flavonoids glycosides(>50% in 20 lg mL�1) exhibited higher estrogen-like activity thanflavonoids aglycone (<50% in 20 lg mL�1, except for quercetin(9)) because of the presence of glycosyl groups, which indicatedthat glycosyl groups significantly favor the effect. The presentstudy also showed that flavonoids compounds displayed higherestrogen-like activity because they might differentially regulatearomatase transcription in breast cells MCF-7 in addition to theinhibition at the enzyme level.17

In alkaloids compounds group (19–23) including four isoquino-line alkaloids (19–22) and one amide alkaloids (23), isoquinoline

alkaloids (>50% in 20 lg mL�1) exhibited more estrogenic activitythan amides (<40% in 20 lg mL�1). It indicated that more OCH3

groups on the benzene ring would increase the activity becausetetrahydropulmatine (19) and palmatine hydrochloride (20)showed stronger estrogenic activity (>60% in 20 lg mL�1) thanberberine (21) and jatrorrhizine chloride (22) (<60% in 20 lg mL�1) in isoquinolines alkaloids. It also showed that alkaloid exhib-ited higher estrogen-like activity than alkaloid salt because of tet-rahydropulmatine (19) with values of 95.00% in 20 lg mL�1.

Lactones compounds (24–27) exhibited weaker estrogenicactivity (<50% in 20 lg mL�1 compared with other groups. Maybelactones compounds wouldn’t be as potent SERMs.

In other compounds group, all compounds showed strong estro-genic activity (>60% in 20 lg mL�1). Linoleic acid (28) with higherestrogenic activity (141.67% in 20 lg mL�1) might act as a morepotent estrogen agonist. Anisole (29) and aucubin (30) with estro-genic activities (100% in 20 lg mL�1) could also be as potentestrogen agonists. Cinnamaldehyde (32) and benzaldehyde (38)possessed biphasic activity, which exhibited high estrogenic activ-ity at low concentration, and the activity was reversed at high con-centration. Maybe aldehyde group in the benzene ring wasresponsible for the biphasic activity.

Figure 2. Compounds (% E2 induction 20 lg mL�1 >60%) (green) docked into interacting residues of ER-a (white). The values of interacting residues of each compound wereshown in Table 3. The number of each compound in the manuscript was marked in the upper left corner (white).

162 L. Liu et al. / Bioorg. Med. Chem. Lett. 22 (2012) 154–163

High-throughput docking and scoring methods can be appliedto perform structure-based screening. One of the most widely usedprograms is FlexX18 that can be used for protein–ligand dockingfollowing an incremental construction algorithm while thereceptor is kept rigid. To further rationalize the observed ER-aselectivity of compounds which showed high estrogenic activity(>60% in 20 lg mL�1), a flexible ligand-receptor docking investiga-tion was undertaken.

Selected 22 compounds from this class (estrogenic activity >60%in 20 lg mL�1) demonstrated that 17 compounds exhibited stron-ger binding affinity for ER-a. The accuracy of functional virtualscreening of ER-a modulators by FlexX-Pharm could reach to77.27%. Theoretical affinity of these compounds with respect toER-a was shown in Table 3. Binding mode of these compoundswhen docked into the X-ray crystal structure of ER-a was shownin Figure 1 and residues of ER-a docked with compounds wereshown in Figure 2. In view of the results, compounds from organicaids group and flavones group exhibited stronger binding affinityto ER-a. The accuracy of functional virtual screening of ER-a mod-ulators by FlexX-Pharm in organic aids group and flavones groupcould reach to 100.00%. However, compounds from alkaloids groupdidn’t exhibit stronger binding affinity to ER-a. The results of

estrogen-responsive MCF-7 breast cancer cells and virtual screen-ing by FlexX-Pharm in alkaloids group were inconsistent. It coulddemonstrate that the method was more suitable for organic acidsand flavones, not suitable for alkaloids. Such a promising profileof activities clearly establish these compounds of Si-Wu-Tang ser-ies decoctions as potent SERMs, which maybe selected for furtherdevelopment as potential agents for estrogen related diseases.

Acknowledgments

This research was financially supported by Key ResearchProject in Basic Science of Jiangsu College and University(06KJA36022, 07KJA36024), National Key Technology R&D Program(2008BAI51B01), Graduate Innovation Project of Jiangsu Province(CXZZ11_0791), 2009’ Program for New Century Excellent Talentsby the Ministry of Education (NCET-09-0163), National NaturalScience Foundation of China (30873235), Natural Science Founda-tion of Jiangsu Province, China (BK2008455), 2009’ Program forExcellent Scientific and Technological Innovation Team of JiangsuHigher Education. This research was also supported by ConstructionProject for Jiangsu Key Laboratory for High Technology Research ofTCM Formulae (BM2010576), Construction Project for Jiangsu

L. Liu et al. / Bioorg. Med. Chem. Lett. 22 (2012) 154–163 163

Engineering Center of Innovative Drug from Blood-conditioningTCM Formulae, A Project Funded by the Priority Academic ProgramDevelopment of Jiangsu Higher Education Institutions.

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