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Structure-antiemetic-activity of some diarylheptanoids and their analogues.


The structure-activity relationship Structure-activity relationship is the traditional Practices of Medicinal chemistry which try to modify the effect or the potency of Bioactive chemical compound by modifying its Chemical structure.  of diarylheptanoids and their analogues inhibitory of emesis emesis /em·e·sis/ (em´e-sis) vomiting.

n. pl. em·e·ses
The act or process of vomiting.

The medical term for vomiting.
 induced by copper sulfate sulfate, chemical compound containing the sulfate (SO4) radical. Sulfates are salts or esters of sulfuric acid, H2SO4, formed by replacing one or both of the hydrogens with a metal (e.g., sodium) or a radical (e.g., ammonium or ethyl).  in young chicks was investigated by testing 19 compounds. The compounds are 5 diarylheptanoids isolated from Alpinia katsumadai (Zingiberacea), 5 chemical derivatives of them, 6 analogues isolated from Zingiber officinale Zingiber officinale,
n See ginger.
 rhizome rhizome (rī`zōm) or rootstock, fleshy, creeping underground stem by means of which certain plants propagate themselves. Buds that form at the joints produce new shoots.  (Zingiberaceae), and 3 analogues available on the market. Among them, two types of essential functional structure of diaryiheptanoids and their analogues showed the inhibitory effects against emesis.

Key words: diarylheptanoid, anti-emetic, structure-activity relationship.


Anti-cancer agents frequently cause nausea and vomiting Nausea and Vomiting Definition

Nausea is the sensation of being about to vomit. Vomiting, or emesis, is the expelling of undigested food through the mouth.
 as the side effects Side effects

Effects of a proposed project on other parts of the firm.
. Some traditional Chinese herbal drugs possessing anti-emetic effect seem to be potent against them. We performed systematic survey of anti-emetic compounds from Chinese medicines and other natural materials, finding many active compounds inhibitory of emesis induced by copper sulfate in young chicks. Alpinia species (Zingiberaceae) have been used as an anti-emetic agent and for the treatment of the stomach disease. Among them, A. katsumadai was investigated in detail. We reported its 8 anti-emetic principles, 6 of which are diarylheptanoids (Yang et al., 1999a, b), and concluded that diarylheptanoids are the major anti-emetic principles of A. katsumadai. However, some structurally different diaryl-heptanoids from the same plants showed no anti-emetic activity. In order to find the basic structure of diarylheptanoids effective in inhibiting emesis, we investigated the structure-activity relationship of diarylheptanoids inhibitory of e mesis induced by copper sulfate in young chicks by testing 19 compounds. The compounds are 5 diarylheptanoids isolated from A. katsumadai, 5 chemical derivatives of them, 6 analogues isolated from Zingiber officinale (Zingiberaceae), and 3 analogues available on the market.

Materials and Methods


The anti-emetic activity of 19 diarylheptanoids and their analogues (Fig. 1, 2 and 3) was examined in young chicks against copper sulfate-induced emesis. 6-, 8-, 10-Shogaol (1-3) and 6-, 8-, 10-gingerol (4-6) were isolated from Zingiber officinale in our laboratory (Akita et al., 1998). trans, trans-1,7-Diphenyl-4,6-heptadien-3-one (7), trans, trans-1,7-diphenyl-5-hydroxy-4,6-heptadien-3-one (8), (5R)-trans-1,7-diphenyl-5-hydroxy-6-hepten-3-one (9), (3S, 5S)-trans-3,5-dihydroxy- 1,7-diphenyl-1-heptene (10), and (3R,5S)-trans3,5-dihydroxy-1,7-diphenyl-1-heptene (11) were isolated from Alpinia katsumadai (Yang et al., 1999a). 1,7-Diphenyl-heptane-3-one (12), dihydroyashabushiketol (14), (3S,5R)-3,5-dihydroxy-1,7-diphenyl-heptane (15), and (3S,5S)-3,5-dihydroxy-1,7-diphenylheptane (16) were prepared from compound 7, 9, 10 and 11 by hydrogenation over palladium carbon, respectively. trans, trans-1,7-Diphenyl-1,3-heptadien-5-ol (13) was prepared from compound 7 by reducing with [NaBH.sub.4]. trans-4-Phenyl-3-buten -2-one (17) was purchased from Wako Pure Chemicals Industries Ltd. (Japan). 4-Phenylbutan-2-one (18) and trans-4-phenyl-3-buten-2ol (19) were prepared from compound 17.

1,7-Diphenyl-heptane-3-one (12)

A mixture of 7 (100.8 mg) was hydrogenated at room temperature by using 5% Pd/C catalyst (30 mg) in MeOH (50 ml). The reaction mixture was filtered, and the filtrate filtrate /fil·trate/ (fil´trat) a liquid or gas that has passed through a filter.

To put or go through a filter.

 was evaporated under the reduced pressure In thermodynamics, the reduced pressure of a fluid is defined as its actual pressure divided by its critical pressure.

 to give compound 12 (52.7 mg). [H.sup.1]-NMR (CD[Cl.sub.3]) [delta]: 1.58-1.61 (4H, m), 2.40 (2H, t, J = 7 Hz), 2.59 (2H, t, J = 7 Hz), 2.70 (2H, m), 2.88 (2H, t, J = 8 Hz), 7.14-7.28 (10H, m); [C.sup.13]-NMR (CD[Cl.sub.3]) [delta]: 23.4 ([CH.sub.2]), 29.8 ([CH.sub.2]), 30.9 ([CH.sub.2]), 35.7 ([CH.sub.2]), 42.8 ([CH.sub.2]), 44.2 ([CH.sub.2]), 125.6 (CH), 125.9 (CH), 128.1 (CH), 128.2 (CH), 128.3 (CH), 141.0 (C), 142.0 (C), 209.7 (C).

trans, trans-1,7-Diphenyl-1,3-heptadien-5-ol (13)

A solution of 7 (300 mg) in MeOH (10 ml) was added with [NaBH.sub.4] (80 mg) and stirred for 1 hour at room temperature. The reaction mixture was neutralized with 1N HCl and extracted with CH[Cl.sub.3]. After drying with anhydrous an·hy·drous
Without water, especially water of crystallization.

anhydrous (anhī´drus),
adj without water.


containing no water.
 [Na.sub.2][SO.sub.4], the organic extract was evaporated under the reduced pressure to give a residue, which was chromatographed on HPLC HPLC high-performance liquid chromatography.


high performance liquid chromatography.

HPLC High-performance liquid chromatography Lab instrumentation A highly sensitive analytic method in which analytes are placed
 [silica-4251-N 10[PHI] x 250 mm, n-hexane-acetone (8:2)] to afford compound 13 (42.4 mg). [H.sup.1]-NMR (CD[Cl.sub.3]) [delta]: 1.92 (2H, m), 2.73 (2H, m), 4.23 (1H, q, J = 7 Hz), 5.85 (1H, dd, J = 15, 7 Hz), 6.39 (1H, dd, J = 15, 10 Hz), 6.55 (1H, d, J = 15 Hz), 6.77 (1H, dd, J = 15, 10Hz), 7.19-7.45 (10H, m); [C.sup.13]-NMR (CD[Cl.sub.3]) [delta]: 31.7 ([CH.sub.2]), 38.7 ([CH.sub.2]), 71.9 (CH), 125.7 (CH), 126.2 (CH), 127.5 (CH), 128.0 (CH), 128.3 (CH), 128.5 (CH), 129.0 (CH), 130.8 (CH), 132.7 (CH), 136.1 (CH), 136.9 (C), 141.6 (C). Those NMR NMR: see magnetic resonance.  spectral data agreed with published data (Claeson et al., 1993).

Dihydroyashabushiketol (14)

A mixture of 9 (188.0 mg) was hydrogenated at room temperature by using 5% Pd/C catalyst (50 mg) in MeOH (100 ml). The reaction mixture was filtered, and the filtrate was evaporated under the reduced pressure to give compound 14 (119.1 mg). [H.sub.1]-NMR (CD[Cl.sub.3]) [delta]: 1.62-1.84 (1H, m), 2.48-2.91 (8H, m), 3.04 (1H, br), 4.04 (1H, q, J = 3 Hz), 7.15-7.29 (10H, m). Those NMR spectral data agreed with published data (Kuroyanagi et al., 1983).

(3S,5R)-3,5-Dihydroxy-1,7-diphenylheptane (15)

A mixture of 10 (51.5 mg) was hydrogenated at room temperature by using 5% Pd/C catalyst (15 mg) in MeOH (25 ml). The reaction mixture was filtered, and the filtrate was evaporated under the reduced pressure to give compound 15 (32.8 mg). [[[alpha]].sub.D] [+ or -] 0[degrees] (c = 0.38, EtOH). HREIMS m/z: 284.1775, calcd for [C.sub.19][H.sub.24][O.sub.2], 284.1776. [H.sub.1]-NMR (CD[Cl.sub.3]) [delta]: 1.55-1.83 (6H, m), 2.64-2.91 (4H, m), 3.48 (2H, br), 3.87 (2H, m), 7.17-7.30 (10H, m). Those spectral data agreed with published data (Kuroyanagi et al., 1983).

(3S,5S)-3,5-Dihydroxy-1,7-diphenylheptane (16)

A mixture of 11 (39.4 mg) was hydrogenated at room temperature by using 5% Pd/C catalyst (15 mg) in MeOH (25 ml). The reaction mixture was filtered, and the filtrate was evaporated under the reduced pressure to give compound 16 (38.6 mg). [[[alpha]].sub.D] -5.3[degrees] (c = 0.46, EtOH). HREIMS m/z: 284.1772, calcd for [C.sub.19][H.sub.24][O.sub.2], 284.1776. [H.sup.1]-NMR (CD[Cl.sub.3]) [delta]: 1.74-1.88 (6H, m), 2.60-2.79 (4H, m), 3.48 (2H, br), 3.99 (2H, m), 7.15-7.31 (10H, m).

4-Phenyl butan-2-one (18)

A mixture of 17 (1080 mg) was hydrogenated at room temperature by using 5% Pd/C catalyst (300 mg) in MeOH (30 ml). The reaction mixture was filtered, and the filtrate was evaporated under the reduced pressure to give compound 18 (1001 mg). [H.sup.1]-NMR ([CDCl.sub.3]) [delta]: 2.13 (3H, s), 2.75 (2H, t, J = 8 Hz), 2.89 (2H, t, J = 8 Hz), 7.16--7.30 (5H, m); [C.sup.13]-NMR ([CDCl.sub.3]) [delta]: 29.8 ([CH.sub.3]), 30.1 ([CH,sub.2]), 45.2 ([CH.sub.2]), 126.0 (CH), 128.2 (CH), 128.3 (CH), 128.4 (CH), 140.8 (C), 207.7 (C).

trans-4-Phenyl-3-buten-2-ol (19)

A solution of 17 (1032.0 mg) in MeOH (30 ml) was added with NaBH4 (250 mg) and stirred for 1 hour at room temperature. The reaction mixture was neutralized with 1N HCI (Human Computer Interaction) Refers to the design and implementation of computer systems that people interact with. It includes desktop systems as well as embedded systems in all kinds of devices. , and then was extracted with [CHCl.sub.3]. After drying with anhydrous [Na.sub.2][SO.sub.4], the organic extract was evaporated under the reduced pressure to afford compound 19 (980 mg). [H.sup.1]-NMR ([CDCl.sub.3]) [delta]: 1.35 (3H, d, J = 8 Hz), 4.78 (1H, ddd, J = 8, 8, 2 Hz), 6.25 (1H, dd, J = 20, 8 Hz), 6.55 (1H, d, J = 20 Hz), 7.22--7.39 (5H, in); [C.sup.13]-NMR ([CDCl.sub.3]) [delta]: 23.3 ([CH.sub.3]), 68.9 (CH), 126.4 (CH), 127.6 (CH), 128.2 (CH), 128.5 (CH), 128.9 (CH), 129.3 (CH), 133.5 (CH), 136.6 (C).

Spectrometry and chromatography

The [[alpha].sub.D] values were determined with a JASCO JASCO Japan-America Society of Central Ohio  DIP-140 digital polalimeter. The [H.sup.1] and [C.sup.13]-NMR spectra were recorded by using a JEOL JEOL Japan Electron Optics Laboratory  GSX-400 spectrometer in [CDCl.sub.3] with tetramethylsilane as the internal standard. Kieselgel-60[F.sub.254] (MERCK)-precoated plates were employed for thin-layer chromatography (TLC TLC total lung capacity; thin-layer chromatography.

1. thin-layer chromatography

). Column chromatography column chromatography
A form of partition chromatography in which a liquid phase flows down a column packed with a solid phase.
 was carried out on 70--230 mesh silica gel (MERCK). HPLC was performed by using an SSC-3100-J pump with an Oyo-Bunko Uvilog 7 UV detector. HREIMS were obtained by using a JEOL JMX-DX 302.

Bioassay of anti-emetic activity

The young male chicks weighing 25-35 g (Goto Furanjo Co., Inc. Saitama, Japan) were divided into 1-3 groups consisting of six each. The young chicks were set aside for 10 mm and stabilized in large beakers at 25 [degrees]C. The sample solution was administered intraperitoneally in a dose of 10 ml/kg. After 10 mm, copper sulfate anhydride anhydride (ănhī`drīd, –drĭd) [Gr.,=without water], chemical compound formed by removing water, H2O, from another compound; the anhydride can also react with water to form the original compound.  was administered orally in a dose of 50 mg/kg, then the number of retching retching /retch·ing/ (rech´ing) strong involuntary effort to vomit.


an unproductive effort to vomit.
 (an emetic emetic (əmĕt`ĭk), substance that produces vomiting. Direct, or gastric, emetics, which act directly on the stomach, include syrup of ipecac, sulfate of zinc or copper, alum, ammonium carbonate, mustard in water, or copious quantities of  action without vomiting gastric materials) was recorded during the next to mm. The results were judged by the decrease in numbers of retching compared with those of control. The inhibition (%) was calculated as follows:

Inhibition (%) = [(A-B)/A]x100

A: control frequency of retching

B: frequency of retching after sample treatment

Statistical analysis: all numerical data were expressed as the mean [+ or -] S. E. M. The statistical significance of the difference was determined by an unpaired Student's t-test.

Results and Discussion

We have been already reported (Akita et al., 1998) that the known anti-emetics, chloropromazine, metoclopramide and ethyl ethyl (ĕth`əl), CH3CH2, organic free radical or alkyl group derived from ethane by removing one hydrogen atom.  p-aminobenzoate, showed antiemetic activities at the dose of 50 mg/kg in this assay method. On the basis of the results, all compounds were tested at the dose.

We are searching for anti-emetic principles from natural sources. Some diarylheptanoids showed antiemetic acitivity, but not all, depending on their partial structures. Following our previous findings that shogaol and gingerols showed the anti-emetic activity (Akita et al., 1998), we found that anti-emetic active diarylheptanoids posess the similar functional groups in their structure. As shown in Table 1 (Akita et al., 1998) and 2, compounds 1-6, 7, 9-11, 13-16 showed the anti-emetic activity in a dose of 50 mg/kg, and compounds 8, 12, 17-19 showed no effects. After analyzing the structure of these diarylheptanoids and related compounds, the anti-emetic compounds were classified into two groups. As shown in Fig. 1, compounds 1-3, 7, 13, which contain A type functional structure, were classified into A group. Compounds 4-6, 9-11, 14-16, which contain B type functional structure (Fig. 2) and showed the anti-emetic activity, were classified into B group. Compounds 8, 12, 17-19, which showed no anti-emetic effec ts, contain neither A nor B type functional structure (Fig. 3). These results revealed that A and B type functional structures are the essential structural parts of the compounds to show the anti-emetic activity. This finding would be important for the anti-emetic drug design and synthesis in the future.

Diarylheptanoids are very common in the Zingiberaceae, and are isolated from A. officinarum (Itokawa et al., 1981, 1985; Uehara et al., 1987), A. oxyphylla (Itokawa et al., 1982; Shoji shoji

In Japanese architecture, sliding partition doors and windows made of a latticework wooden frame and covered with a tough, translucent white paper. When closed, they softly diffuse light throughout the house.
 et at., 1984), A. conchigera (Athamprasangsa et al., 1994), A. bleparocalyx (Kadota et al., 1994), and Curcuma cur·cu·ma  
Any of various tropical Asian plants of the genus Curcuma, which includes turmeric and zedoary.

[New Latin Curcuma, genus name, from Arabic kurkum, saffron
 comosa and C. xanthorrhiza (Uehara et al., 1987). These have been used as the anti-emetics in Chinese traditional medicine Chinese traditional medicine

an ancient health care system based on the concept of vital energy (Qi) and the opposing forces of yin (negative energy) and yang (positive energy). It incorporates herbal medicine, exercises, meditation and acupuncture.
. As shown in Fig. 4, these diarylheptanoids also contain A or B type partial structure. Therefore, we concluded that diarylheptanoids of types A and B might be the main and common anti-emetic principles of Zingiberaceae.




Table 1

Anti-emetic effects of 6-, 8-, 10-shogaol (1-3) and 6-, 8-, 10-
gingerol (4-6) on copper sulfate induced-emesis in young chicks (Akita
et al., 1998).

Drugs            Dose (mg/kg)  No. of young chicks

control                        5
6-shogaol (1)    50            6
control                        6
8-shogaol(2)     50            6
control                        6
10-shogaol (3)   50            6
control                        6
6-gingerol (4)   50            6
control                        6
8-gingerol (5)   50            6
control                        6
10-gingerol (6)  50            5

Drugs            No. of retching           Inhibition (%)
                 (mean [+ or -] S. E. M.)

control          39.6 [+ or -] 1.52
6-shogaol (1)    19.8 [+ or -] 2.34 ***    49.2
control          41.0 [+ or -] 1.67
8-shogaol(2)     19.0 [+ or -] 2.13 ***    53.7
control          50.3 [+ or -] 2.20
10-shogaol (3)   15.6 [+ or -] 3.17 ***    69.0
control          45.7 [+ or -] 2.79
6-gingerol (4)   19.2 [+ or -] l.74 ***    58.0
control          45.5 [+ or -] 2.28
8-gingerol (5)   21.5 [+ or -] 2.25 ***    52.7
control          40.2 [+ or -] 1.30
10-gingerol (6)  21.6 [+ or -] 3.61 ***    46.3

Significantly different from the control value

*** p < 0.001.
Table 2

Anti-emetic effects of diarylheptanoids and related compounds on copper
sulfate induced-emesis in young chicks.

Drugs    Dose (mg/kg)  No. of young chicks  No. of retching
                                            (mean [+ or -] S.E.M.)

control                6                    84.4 [+ or -] 1.31
7        50            6                    53.8 [+ or -] 4.01 **
control                6                    82.2 [+ or -] 2.27
8        50            6                    64.7 [+ or -] 5.22
control                6                    75.8 [+ or -] 2.33
9        50            6                    33.5 [+ or -] 3.71 **
control                6                    82.2 [+ or -] 2.27
10       50            6                    36.5 [+ or -] 2.20 **
control                6                    74.2 [+ or -] 4.76
11       50            6                    21.7 [+ or -] 1.19 ***
control                6                    75.8 [+ or -] 3.67
12       50            6                    70.0 [+ or -] 2.65
control                6                    75.8 [+ or -] 3.67
13       50            6                    38.4 [+ or -] 4.62 **
control                6                    78.7 [+ or -] 3.19
14       50            6                    41.7 [+ or -] 1.47
control                6                    73.7 [+ or -] 3.11
15       50            6                    38.5 [+ or -] 4.53 ***
control                6                    77.5 [+ or -] 2.77
16       50            6                    41.0 [+ or -] 3.94 ***
control                6                    78.7 [+ or -] 3.19
17       50            6                    63.2 [+ or -] 4.36
control                6                    77.5 [+ or -] 2.77
18       50            6                    61.0 [+ or -] 4.26
control                6                    78.7 [+ or -] 3.19
19       50            6                    67.8 [+ or -] 4.44

Drugs    Inhibition (%)

7        36.6
8        17.3
9        55.6
10       55.6
11       70.8
12        7.5
13       47.4
14       46.9
15       47.8
16       47.1
17       19.7
18       21.3
19       13.8

Significantly different from the control value

** p < 0.01

*** p < 0.001.


The authors would like to thank Professor emeritus Shoji Shibata, University of Tokyo “Todai” redirects here. For the restaurant called Todai, see Todai (restaurant).

The University of Tokyo (東京大学
, for his encouragement. This study was partly supported by Sasakawa Scientific Research Grant from Japan Science Society (1996-7).


Akita, Y, Yang, Y, Kawai, T., Kinoshita, K., Koyama, K., Takahashi, K., Watanabe, K.: New assay method for surveying anti-emetic compounds from natural sources. Nat. Prod. Sci. 4 (2): 72-77, 1998.

Athamprasangsa, S., Buntrarongroj, U., Dampawan, P., Ongkavoranan, N., Rukachaisirikul, V., Sethijinda, S., Sornnarintra, M., Sriwub, P., Taylor, W.C.: A 1,7- diarylheptanoid from Alpinia conchigera. Phytochemistry phytochemistry,
n the scientific study and classification of the chemical constituents of plants.
 37: 871-873, 1994.

Claeson, P., Panthong, A., Tuchinda, P., Reutrakul, V., Kanjinapoyhi, D., Taylor, W., Santisuk, T.: Three non-phenolic diarylheptanoids with anti-inflammatory activity from Curuma xanthorrhiza. Planta Med. 59: 451-454, 1993.

Itokawa, H., Morita, M., Mihashi, S.: Two new diarylheptanoids from Alpinia officinarum HANCE. Chem. Pharm. Bull. 29: 2383- 2385, 1981.

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Kadota, S., Hui, D., Basnet, P., Prasain, J., Xu, G.-X., Namba, T.: Three novel diarylheptanoids, calyxin A, calyxin B, and 3-epi-calyxin B from a Chinese crude drug "Yunnan Cao Kou" (Alpinia blepharocalyx K. SCHVM). Chem. Pharm. Bull. 42: 2647-2649, 1994.

Kuroyanagi, M., Noro, T., Fukushima, S., Aiyama, R., Ikuta, A., Itokawa, H., Morita, M.: Studies on the constituents of the seeds of Alpinia katsumadai Hayata. Chem. Pharm. Bull. 31: 1544-1550, 1983.

Shoji, N., Umeyama, A., Takemoto, T., Ohizhumi, Y: Isolation of a cardiotonic principle from Alpinia oxyphylla. Planta Med. 50: 186-187, 1984.

Uehara, S. I., Yasuda, I., Akiyama, K., Morita, H., Takeya, K., Itokawa, H.: Dirarylheptanoids from the rhizome of Curcuma xanthorrhiza and Alpinia officinarum. Chem. Parm. Bull. 35: 3298-3304, 1987.

Yang, Y., Kinoshita, K., Koyama, K., Takahashi, K., Tai, T., Nunoura, Y, Watanabe, K.: Anti-emetic principles of Alpinia katsumadai Hayata. Nat. Prod. Sci. 5 (1): 20-24, 1999a.

Yang, Y, Kinoshita, K., Koyama, K., Takahashi, K., Tai, T., Nunoura, Y, Watanabe, K.: Two novel anti-emetic principles of Alpinia katsumadai. J. Nat. Prod. 62: 1672-1674, 1999b.

Y. Yang (1), K. Kinoshita (1), K. Koyama (1), K. Takahashi (1), S. Kondo (2) and K. Watanabe (3)

(1) Department of Pharmacognosy pharmacognosy /phar·ma·cog·no·sy/ (fahr?mah-kog´nah-se) the branch of pharmacology dealing with natural drugs and their constituents.

 and Phytochemistry, Meiji Pharmaceutical (1University, Tokyo, Japan

(2) Kotaro Pharmaceutical Co. Ltd., Osaka, Japan

(3) Faculty of Pharmaceutical Sciences, Chiba University, Chiba, Japan


K. Takahashi, Department of Pharmacognosy and Phytochemistry, Meiji Pharmaceutical University, Noshio 2-522-1, Kiyose-shi, Tokyo 204-8588, Japan.

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Author:Yang, Y.; Kinoshita, K.; Koyama, K.; Takahashi, K.; Kondo, S.; Watanabe, K.
Publication:Phytomedicine: International Journal of Phytotherapy & Phytopharmacology
Date:Mar 1, 2002
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