湖北旋覆花化學(xué)成分的研究

張 飛，覃江江，成向榮，金慧子*，張衛(wèi)東，2*

1上海交通大學(xué)藥學(xué)院，上海200240;2第二軍醫(yī)大學(xué)藥學(xué)院，上海200433

Introduction

The genus Inula，a variable perennial herb distributed in Asia，Europe，Africa，and predominantly，in the Mediterranean，comprises ca.100 species of the Asteraceae family belonging to the tribe Inuleae［1］.The plant Inula hupehensis，the roots of which have been used to treat many diseases，including bronchitis，diabetes，and intestinal ulcers［2］，is an endemic plant distributed in Hubei and Sichuan Provinces in China.So far，only a few compounds have been reported from this plant.In order to do further investigations on the aerial parts of I.hupehensis，we isolated and identified nineteen compounds，including 9-hydroxythymol(1)，8，10-dehydro-9-hydroxythymol(2)，2-hydroxy-4-methylacetophenone (3)，8，9-dihydroxythymol(4)，10-hydroxy-8，9-dioxyisopropylidenethymol(5)，8，10-dihydroxy-9-isobutyryloxythymol(6)，8-hydroxy-9-［(isobutyryl)oxy］-10-(2-methylbutanoyl)thymol(7)，8，9，10-trihydroxythymol(8)，8-hydroxy-9，10-diisobutyryloxythymol(9)，neoechinulin A(10)，3-formyl-indole(11)，3-(hydroxyl-acetyl)-1H-indole(12)，syringic acid(13)，4，6-dihydroxy-2-methoxyacetophenone(14)，daphne-tin 7-methyl ether(15)，6-methoxykaemaferol(16)，(+)-syringaresinol(17)，α-monopalmitin(18)，and stigmasterol(19).All the compounds except compounds 8 and 9 were obtained from this plant for the first time.

Experimental

General procedures

The normal phase silica gel(200～300 mesh，Yantai，China)，MCI gel(CHP20P 75～150 μm，Mitsubishi Chemical Co.，Japan)，and Sephadex LH-20(GE Healthcare Bio-Sciences AB，Sweden)were used for column chromatography，and precoated silica HSGF254plates were used for TLC(Yantai，China).HPLC and preparative HPLC were performed with SHIMADZU LC 2010AHT，Agilent Technologies 1200 series and SHIMADZU LPD-20A.Melting points were measured with an RY-2 micromelting point apparatus and were uncorrected.ESI-MS were recorded on Q-TOF micro mass spectrometer.1H and13C NMR spectra were measured on a Bruker DRX-500 spectrometer.Chemical shift (β)were given in ppm relative to TMS as internal reference and coupling constants(J)in Hz.

Plant material

The aerial parts of I.hupehensis were collected from Enshi city of Hubei Province，China，in July，2007 and identified by Prof.Huang Bao-kang，Department of Pharmacognosy，School of Pharmacy，Second Military Medical University.A voucher specimen (No.200707XHFHB)has been deposited at School of Pharmacy，Shanghai Jiao Tong University.

Extraction and isolation

The air-dried and powdered aerial parts of I.hupehensis (25.0 kg)were extracted with 95%EtOH for three times at room temperature.After concentration of the combined extracts under reduced pressure，the residue (3.0 kg)was suspended in H2O and then partitioned successively with petroleum ether，EtOAc and n-butanol，yielding 230.9 g，148.3 g and 322.6 g，respectively.The EtOAc fraction was chromatographed on a silica gel column eluted with CH2Cl2-MeOH (100% to 50%)to obtain 7 fractions(Frs.1-7).Fr.1(28.5 g) wasapplied to MCIgelcolumn chromatography (MeOH-H2O，4∶1)and purified by Sephadex LH-20 (MeOH)，yielding compounds 7(77.1 mg)，9(443.9 mg)and 19(1103.0 mg).Fr.2(19.6 g)was subjected to MCI gel(MeOH-H2O，4:1)，Sephadex LH-20 (MeOH)chromatography，and purified by preparative HPLC(RP-18，210 nm，45%MeOH)to give compounds 1(6.1 mg)，2(3.0 mg)，3(42.5 mg)，5(9.0 mg)，10(29.7 mg)，11(5.1 mg)，13(58.3 mg)，14 (4.0 mg)，15(7.2 mg)and 18(100.8 mg).Compound 6(53.7 mg)was obtained after the purifications of Fr.3(11.6 g)by MCI gel(MeOH-H2O，4∶1)and Sephadex LH-20(MeOH)chromatography.Fr.4(9.3 g)was chromatographed on MCI gel(MeOH-H2O，4∶1)and Sephadex LH-20(MeOH)，and purified by preparative HPLC(RP-18，210 nm，45%MeOH)to yield compounds 4(21.7 mg)，8(5.1 mg)and 12 (2.0 mg).Fr.5(6.5 g)was subjected to MCI gel (MeOH-H2O，4∶1)，Sephadex LH-20(MeOH)chromatography，and purified by preparative HPLC(RP-18，210 nm，40% MeOH)to give compounds 16 (301.8 mg)and 17(12.3 mg).

Structure identification

9-Hydroxythymol(1) colorless oil，C10H14O2;ESIMS(pos.)m/z 189［M+Na］+;ESI-MS(neg.)m/z 165［M-H］-;1H NMR(CDCl3，400 MHz)δ:6.71 (1H，brs，H-2)，7.00(1H，d，J=8.2 Hz，H-5)，6.72 (1H，brd，J=8.2 Hz，H-6)，2.28(3H，s，H3-7)，3.20(H，m，H-8)，3.92(1H，dd，J=9.8，3.8 Hz，H-9a)，3.71(1H，dd，J=9.8，8.0 Hz，H-9b)，1.30 (3H，d，J=7.3 Hz，H3-10);13C NMR(CDCl3，100 MHz)δ:137.9(C-1)，117.8(C-2)，154.6(C-3)，127.5(C-4)，127.6(C-5)，121.5(C-6)，20.9(C-7)，36.6(C-8)，69.5(C-9)，15.7(C-10).The NMR and MS data were in accordance with those reported in the literature［3］，and identified 1 as 9-hydroxythymol.

8，10-Dehydro-9-hydroxythymol(2) colorless oil，C10H12O2;ESI-MS(pos.)m/z 187［M+Na］+;ESIMS(neg.)m/z 163［M-H］-;1H NMR(CDCl3，400 MHz)δ:6.74(1H，brs，H-2)，7.02(1H，d，J= 7.8 Hz，H-5)，6.69(1H，brd，J=7.8 Hz，H-6)，2.30 (3H，s，H3-7)，4.40(2H，brs，H2-9)，5.47(1H，brs， H-10a)，5.36(1H，brs，H-10b);13C NMR(CDCl3，100 MHz)δ:139.9(C-1)，117.2(C-2)，153.5(C-3)，123.8(C-4)，129.4(C-5)，121.0(C-6)，21.1 (C-7)，145.5(C-8)，67.1(C-9)，119.1(C-10) .The MS and NMR data were in agreement with those reported in the literature［4］，and identified 2 as 8，10-dehydro-9-hydroxythymol.

2-Hydroxy-4-methylacetophenone(3) colorless oil，C9H10O2;ESI-MS(pos.)m/z 173［M+Na］+; ESI-MS(neg.)m/z 149［M-H］-;1H NMR (CD3OD，400 MHz)δ:6.73(1H，brs，H-2)，7.72 (1H，d，J=8.1 Hz，H-5)，6.75(1H，brd，J=8.1 Hz，H-6)，2.31(3H，s，H3-7)，2.57(3H，s，H3-9);13C NMR(CD3OD，100 MHz)δ:149.6(C-1)，119.2 (C-2)，163.7(C-3)，119.1(C-4)，132.5(C-5)，121.7(C-6)，22.2(C-7)，206.1(C-8)，26.9(C-9) .The MS and NMR data were consistent with those of reported［5］，and identified 3 as 2-hydroxy-4-methylacetophenone.

8，9-Dihydroxythymol(4) colorless oil，C10H14O3; ESI-MS(pos.)m/z 205［M+Na］+;ESI-MS(neg.) m/z 181［M-H］-;1H NMR(CDCl3，400 MHz)δ: 6.57(1H，brs，H-2)，7.05(1H，d，J=8.0 Hz，H-5)，6.61(1H，brd，J=8.0 Hz，H-6)，2.21(3H，s，H3-7)，3.71(1H，d，J=11.2 Hz，H-9a)，3.59(1H，d，J =11.2 Hz，H-9b)，2.00(3H，s，H3-10);13C NMR (CDCl3，100 MHz)δ:139.8(C-1)，118.4(C-2)，157.1(C-3)，127.7(C-4)，128.1(C-5)，121.4(C-6)，21.3(C-7)，78.1(C-8)，70.5(C-9)，25.0(C-10).The MS and NMR data were consistent with those of reported［6］，and identified 4 as 8，9-dihydroxythymol.

10-Hydroxy-8，9-dioxyisopropylidenethymol(5) colorless oil，C13H18O4;ESI-MS(pos.)m/z 261［M+ Na］+;ESI-MS(neg.)m/z 237［M-H］-;1H NMR (CD3OD，400 MHz)δ:6.58(1H，brs，H-2)，7.31 (1H，d，J=7.8 Hz，H-5)，6.63(1H，brd，J=7.8 Hz，H-6)，2.23(3H，s，H3-7)，4.40(1H，d，J=9.0 Hz，H-9a)，4.16(1H，d，J=9.0 Hz，H-9b)，3.73(1H，d，J=11.5 Hz，H-10a)，3.61(1H，d，J=11.5 Hz，H-10b)，1.27(3H，s，H3-2')，1.52(3H，s，H3-3');13C NMR(CD3OD，100 MHz)δ:139.8(C-1)，117.4 (C-2)，154.9(C-3)，127.6(C-4)，128.8(C-5)， 121.2(C-6)，21.4(C-7)，86.8(C-8)，72.6(C-9)，67.6(C-10)，110.9(C-1')，27.5(C-2')，26.2 (C-3').The above data were in agreement with those of reported［3］，and identified 5 as 10-hydroxy-8，9-dioxyisopropylidenethymol.

8，10-Dihydroxy-9-isobutyryloxythymol(6) colorless oil，C14H20O5;ESI-MS(pos.)m/z 291［M+ Na］+;ESI-MS(neg.)m/z 267［M-H］-;1H NMR (CD3OD，500 MHz)δ:6.60(1H，d，J=1.0 Hz，H-2)，7.16(1H，d，J=8.0 Hz，H-5)，6.64(1H，dd，J =8.0，1.0 Hz，H-6)，4.56(1H，d，J=11.5 Hz，H-9a)，4.40(1H，d，J=11.5 Hz，H-9b)，3.91(1H，d，J=11.5 Hz，H-10a)，3.84(1H，d，J=11.5 Hz，H-10b)，2.49(1H，m，H-2')，2.23(3H，s，H3-7)，1.06 (3H，d，J=7.0 Hz，H3-3')，1.03(3H，d，J=7.0 Hz，H3-4');13C NMR(CD3OD，125 MHz)δ:139.9(C-1)，118.0(C-2)，156.6(C-3)，123.9(C-4)，128.6 (C-5)，121.1(C-6)，21.0(C-7)，78.7(C-8)，68.2 (C-9)，66.6(C-10)，178.8(C-1')，35.1(C-2')，19.2(C-3')，19.1(C-4').The above data were consistent with those of reported［3］，and identified 6 as 8，10-dihydroxy-9-isobutyryloxythymol.

8-Hydroxy-9-［(isobutyryl)oxy］-10-(2-methylbutanoyl)thymol(7) colorless oil，C19H28O6;ESI-MS (pos.)m/z 375［M+Na］+;ESI-MS(neg.)m/z 351［M-H］-;1H NMR(CDCl3，500 MHz)δ:6.70 (1H，d，J=1.0 Hz，H-2)，6.89(1H，d，J=8.0 Hz，H-5)，6.64(1H，dd，J=8.0，1.0 Hz，H-6)，2.27 (3H，s，H3-7)，4.45(4H，m，H2-9，H2-10)，2.56 (1H，m，H-2')，1.13(each 3H，d，J=7.0 Hz，H3-3'，4')，2.40(1H，m，H-2'')，1.62(1H，m，H-3''a)，1.44(1H，m，H-3''b)，1.10(3H，d，J=7.0 Hz，H3-5'')，0.83(3H，m，H3-4'');13C NMR(CDCl3，125 MHz)δ:140.1(C-1)，118.7(C-2)，156.7(C-3)，118.7(C-4)，126.5(C-5)，120.5(C-6)，21.0(C-7)，78.9(C-8)，67.3(C-9)，67.4(C-10)，177.5 (C-1')，33.9(C-2')，18.8(C-3'，4')，177.2(C-1'')，41.0(C-2'')，16.5(C-3'')，26.6(C-4'')，11.43(C-5'').The above data were consistent with those of reported［7］，and identified 7 as 8-hydroxy-9-［(isobutyryl)oxy］-10-(2-methylbutanoyl)thymol.

8，9，10-Trihydroxythymol(8) colorless oil，C10H14O4;ESI-MS(pos.)m/z 221［M+Na］+;ESI-MS (neg.)m/z 197［M-H］-;1H NMR(CD3OD，500 MHz)δ:6.58(1H，d，J=0.8 Hz，H-2)，7.16(1H，d，J=8.0 Hz，H-5)，6.62(1H，dd，J=8.0，0.8 Hz，H-6)，2.22(3H，s，H3-7)，3.85(4H，m，H2-9，H2-10);13C NMR(CD3OD，125 MHz)δ:134.0(C-1)，118.2(C-2)，157.4(C-3)，124.8(C-4)，128.9(C-5)，121.5(C-6)，21.3(C-7)，80.2(C-8)，66.9 (C-9，C-10).The MS and NMR data were consistent with those of reported［8］，and identified 8 as 8，9，10-trihydroxythymol.

8-Hydroxy-9，10-diisobutyryloxythymol(9) colorless oil，C18H26O6;ESI-MS(pos.)m/z 361［M+ Na］+;ESI-MS(neg.)m/z 337［M-H］-;1H NMR (CDCl3，500 MHz)δ:6.69(1H，d，J=1.0 Hz，H-2)，6.91(1H，d，J=8.0 Hz，H-5)，6.65(1H，dd，J =8.0，1.0 Hz，H-6)，2.27(3H，s，H3-7)，4.46 (4H，dd，J=19.0，11.9 Hz，H2-9，H2-10)，2.56 (2H，m，H-2'，H-2'')，1.12(each 3H，d，J=7.0 Hz，H3-3'，3''，4'，4'');13C NMR(CDCl3，125 MHz)δ: 140.0(C-1)，118.5(C-2)，156.4(C-3)，119.0(C-4)，126.5(C-5)，120.5(C-6)，20.9(C-7)，78.5 (C-8)，67.2(C-9，10)，177.5(C-1'，1'')，33.9(C-2'，2'')，18.8(C-3'，3''，4'，4'').The MS and NMR data were consistent with those of reported［3］，and identified 9 as 8-hydroxy-9，10-diisobutyryloxythymol.

Neoechinulin A(10) colorless oil，C19H21N3O2; ESI-MS(pos.)m/z 324［M+H］+;ESI-MS(neg.) m/z 322［M-H］-;1H NMR(CD3OD，400 MHz)δ: 7.42(1H，d，J=8.0 Hz，H-4)，7.06(1H，m，H-5)，7.12(1H，m，H-6)，7.23(1H，d，J=8.0 Hz，H-7)，7.20(1H，s，H-8)，4.21(1H，q，J=7.0 Hz，H-12)，1.52(3H，d，J=7.0 Hz，H3-15)，6.10(1H，dd，J= 17.5，10.5 Hz，H-17)，5.10(1H，d，J=10.5 Hz，H-18a)，5.08(1H，d，J=17.5 Hz，H-18b)，1.54(3H，s，H3-19)，1.53(3H，s，H3-20);13C NMR(CD3OD，100 MHz)δ:146.3(C-1)，125.0(C-2)，137.1(C-3)，113.0(C-4)，121.5(C-5)，122.9(C-6)，120.1 (C-7)，127.6(C-7a)，114.6(C-8)，104.6(C-9)，162.5(C-10)，52.9(C-12)，169.0(C-13)，21.0 (C-15)，40.8(C-16)，146.5(C-17)，112.9(C-18)，28.4(C-19)，28.5(C-20).The above data were in agreement with those of reported［9］，and identified 10 as neoechinulin A.

3-Formyl-indole(11) colorless oil，C9H7NO;ESIMS(pos.)m/z 146［M+H］+;ESI-MS(neg.)m/z 144［M-H］-;1H NMR(CD3OD，400 MHz)δ: 8.08(1H，s，H-2)，8.15(1H，d，J=8.0 Hz，H-4)，7.21(1H，m，H-5)，7.28(1H，m，H-6)，7.46(1H，d，J=8.0 Hz，H-7)，9.88(1H，s，H-8);13C NMR (CD3OD，100 MHz)δ:140.0(C-1)，120.4(C-2)，126.0(C-3)，123.9(C-4)，122.7(C-5)，125.3(C-6)，113.4(C-7)，139.2(C-7a)，187.7(C-8).The above data were in agreement with those of reported［10］，and identified 11 as 3-formyl-indole.

3-(Hydroxy-acetyl)-1H-indole(12) colorless oil，C10H9NO2;ESI-MS(pos.)m/z 176［M+H］+;ESIMS(neg.)m/z 174［M-H］-;1H NMR(CD3OD，400 MHz)δ:8.19(1H，s，H-2)，8.23(1H，d，J= 8.0 Hz，H-4)，7.20(1H，m，H-5)，7.24(1H，m，H-6)，7.44(1H，d，J=8.0 Hz，H-7)，4.72(1H，s，H-8);13C NMR(CD3OD，100 MHz)δ:134.3(C-1)，115.2(C-2)，127.2(C-3)，113.2(C-4)，124.7(C-5)，123.3(C-6)，123.0(C-7)，138.5(C-7a)，196.2(C-8)，66.6(C-9).The above data were in agreement with those of reported［11］，and identified 12 as 3-(hydroxy-acetyl)-1H-indole.

Syringic acid(13) yellow amorphous powder，C9H10O5;ESI-MS(pos.)m/z 221［M+Na］+;ESI-MS (neg.)m/z 197［M-H］-;1H NMR(DMSO-d6，500 MHz)δ:7.21(2H，s，H-2，6)，9.18(1H，brs，4-OH)，3.80(6H，s，5-OCH3)，12.58(1H，brs，7-COOH);13C NMR(DMSO-d6，125 MHz)δ:120.4 (C-1)，106.9(C-2，6)，147.4(C-3，5)，140.2(C-4)，167.2(C-7)，56.0(3，5-OCH3).The above data were consistent with those of reported［12］，and identified 13 as syringic acid.

4，6-Dihydroxy-2-methoxyacetophenone(14) colorless oil，C9H10O4;ESI-MS(pos.)m/z 205［M+ Na］+;ESI-MS(neg.)m/z 181［M-H］-;1H NMR (CD3OD，400 MHz)δ:5.95(1H，d，J=2.2 Hz，H-3)，5.87(1H，d，J=2.2 Hz，H-5)，2.55(3H，s，H3-8)，3.86(3H，s，2-OCH3);13C NMR(CD3OD，100 MHz)δ:106.5(C-1)，168.5(C-2)，97.1(C-3)，167.0(C-4)，92.3(C-5)，165.5(C-6)，204.5(C-7)，33.3(C-8)，56.4(2-CH3).The above data were consistent with those of reported［13］，and identified 14 as 4，6-dihydroxy-2-methoxyacetophenone.

Daphnetin 7-methyl ether(15) white amorphous powder，C10H8O4;ESI-MS(pos.)m/z 215［M+ Na］+;ESI-MS(neg.)m/z 191［M-H］-;1H NMR (DMSO-d6，400 MHz)δ:6.26(1H，d，J=9.5 Hz，H-3)，7.95(1H，d，J=9.5 Hz，H-4)，7.16(1H，d，J= 8.5 Hz，H-5)，7.03(1H，d，J=8.5 Hz，H-6)，3.90 (3H，s，7-OCH3)，9.50(1H，brs，8-OH).The above data were consistent with those of reported［14］，and identified 15 as daphnetin 7-methyl ether.

6-Methoxykaempferol(16) colorless oil，C16H12O7;ESI-MS(pos.)m/z 339［M+Na］+;ESI-MS (neg.)m/z 315［M-H］-;1H NMR(DMSO-d6，400 MHz)δ:6.56(1H，s，H-8)，8.05(2H，d，J= 8.5 Hz，H-2'，6')，6.94(2H，d，J=8.5 Hz，H-3'，5')，3.77(3H，s，6-OCH3);13C NMR(DMSO-d6，100 MHz)δ:135.3(C-2)，146.9(C-3)，176.0(C-4)，151.6(C-5)，130.7(C-6)，157.1(C-7)，93.7(C-8)，151.3(C-9)，103.4(C-10)，121.6(C-1')，115.3(C-2'，6')，129.4(C-3'，5')，159.1(C-4')，59.9(2-CH3).The above data were consistent with those reported［15］，and identified 16 as 6-methoxykaempferol.

(+)-Syringaresinol(17) white amorphous powder，C22H26O8;ESI-MS(pos.)m/z 419［M+H］+; ESI-MS(neg.)m/z 417［M-H］-;1H NMR (CDCl3，400 MHz)δ:6.59(4H，s，H-2，2'，6，6')，4.85(2H，d，J=4.0 Hz，H-7，7')，3.10(2H，m，H-8，8')，4.29(2H，dd，J=9.0，6.7 Hz，H-9a，9'a)，3.90(2H，m，H-9b，9'b)3.90(12H，s，3，3'，5，5'-OCH3);13C NMR(CDCl3，100 MHz)δ:132.0(C-1，1')，102.6(C-2，2'，6，6')，147.1(C-3，3'，5，5')，134.2(C-4，4')，86.1(C-7，7')，54.3(C-8，8')，71.8(C-9，9')，56.4(3，3'，5，5'-OCH3).The above data were consistent with those of reported［16］，and identified 17 as(+)-syringaresinol.

α-Monopalmitin(18) white amorphous powder，C19H38O4;ESI-MS(pos.)m/z 331［M+H］+，353［M+ Na］+，683［2M+Na］+;1H NMR(CDCl3，500 MHz) δ:4.21(1H，dd，J=12.0，5.0 Hz，H-1)，4.15(1H，dd，J=12.0，6.0 Hz，H-1)，3.94(1H，m，H-2)，3.70 (1H，dd，J=11.0，4.0 Hz，H-3)，3.61(1H，dd，J= 11.0，5.5 Hz，H-3)，2.36(2H，t，J=7.5 Hz，H2-5)，1.62(2H，m，H2-6)，1.29(24H，m，H2-7-18)，0.88 (3H，t，J=7.0 Hz，19-CH3);13C NMR(CDCl3，125 MHz)δ:65.1(C-1)，70.2(C-2)，63.3(C-3)，173.1(C-4)，34.1(C-5)，24.9(C-6)，29.3(C-7-16)，31.9(C-17)，22.7(C-18)，14.1(C-19).The above data were consistent with those of reported［17］，and identified 18 as α-monopalmitin.

Stigmasterol(19) white amorphous powder，C29H48O;ESI-MS(pos.)m/z 435［M+H］+;ESI-MS (neg.)m/z 411［M-H］-;13C NMR(CDCl3，125 MHz)δ:71.8(C-3)，140.8(C-5)，121.7(C-6)，50.2(C-9)，56.8(C-14)，56.0(C-17)，138.3(C-22)，129.3(C-23).The above data were consistent with those of reported［18］，and identified 19 as stigmasterol.

1 Zhao YM，Zhang ML，Shi QW，et al.Chemical constituents of plants from the genus Inula.Chem Biodivers，2006，3:371-384.

2 Zhao J，Li Y，Liu Q，et al.Antimicrobial activities of some thymol derivatives from the roots of Inula hupehensis.Food Chem，2010，120:512-516.

3 Liang HX，Bao FK，Dong XP，et al.Antibacterial thymol derivatives isolated from Centipeda minima.Molecules，2007，12:1606-1613.

4 Tori M，Ohara Y，Nakashima K，et al.Thymol derivatives from Eupatorium fortunei.J Nat Prod，2001，64:1048-1051.

5 Shin Y，Lee O，Park C，et al.Two new components from the roots of Angelicae koreana Kitagawa.Chem Nat Compd，2007，43:652-654.

6 Jiang HX，Li Y，Pan J，et al.Terpenoids from Eupatorium fortunei TURCZ.Helv Chim Acta，2006，89:558-566.

7 Su BN，Takaishi Y，Yabuuchi T，et al.Sesquiterpenes and monoterpenes from the bark of Inula macrophylla.J Nat Prod，2001，64:466-471.

8 Monache GD，Monache FD，Becerra J，et al.Thymol derivatives from Eupatorium glechonophyllum.Phytochemistry，1984，23:1947-1950.

9 Yagi R，Doi M.Isolation of an antioxidative substance produced by Aspergillus repens.Biosci Biotechnol Biochem，1999，63:932-933.

10 Luo XM，Qi SH，Tian XP，et al.Studies on chemical constituents of Salinispora pacifica fermentation.Chin Tradit Herb Drugs，2009，40:1710-1712.

11 Xu XL，F(xiàn)an X，Song FX，et al.Chemical constituents of brown alga Leathesia nana.Oceanol Limnol Sin，2005，36:18-23.

12 Dong L，Li L，Liao ZH，et al.Chemical constituents in root of Rhodiola bupleuroides.Acta Bot Boreal-OccidentSin，2007，27:2564-2567.

13 Duan ZH，Shi BJ，Wu LH，et al.Chemical Constituents of Gentiana waltonii.Chin J Nat Med，2007，5:417-420.

14 Jia L，Min ZD.Studies on chemical constituents of Daphne odora.Chin Tradit Herb Drugs，2005，36:1311-1312.

15 Fuchino H，Satoh T，Tanaka N.Chemical evaluation of Betula species in Japan.Ⅲ.Constituents of Betula maximowicziana.Chem Pharm Bull，1996，44:1748-1753.

16 Chen H，HajiA A，Li YC.Isolation and structural identification of chemical constituents from Anabasis brevifolia.Nat Prod Res Dev，2006，18:958-961.

17 Shi Y，Li S，Li HY，et al.Studies on chemical constituents from roots of Pterospermum heterophyllum.China J Chin Mat Med，2008，33:1994-1996.

18 Yang H，Wang D，Tong L，et al.Studies on chemical constituents of Oxytropis falcate(Ⅰ).Chin Pharm J，2008，43:338-340.