全 文 ：多荚草中的新三萜皂甙
丁中涛1 ,2　周　俊1＊　何以能1　戴好富1　谭宁华1
(1.中国科学院昆明植物研究所植物化学开放实验室 , 昆明 650204;2.云南大学化学系 , 昆明 650091)
摘要:　从石竹科植物多荚草(Polycarpon prostratum(Forssk.)Aschers.et Schwein.ex Aschers)中分离得到 3 个新的柴
胡皂甙类化合物:prostratoside A～ C(1～ 3)。它们的结构通过波谱方法分别鉴定为:3_O_{β_D_xylopy ranosyl_(1※2)_β_
D_glucopyranosyl_(1※4)_[ β_D_glucopyranosyl_(1※2)]_α_L_arabinopyranoside}_22α_acetoxy_saikogenin G , 3_O_{β_D_xylopyra-
nosyl_(1※2)_β_D_glucopyranosyl_(1※4)_[ β_D_glucopyranosyl_(1※2)]_α_L_arabinopyranoside}_16α_hydroxy_22α_acetoxy_saiko-
genin E 和 3_O_{β_D_xylopyranosyl_(1※2)_β_D_glucopyranosyl_(1※4)_[ β_D_glucopyranosyl_(1※2)]_α_L_arabinopyranoside}_
21β_acetoxy_saikogenin G.
关键词:　多荚草;石竹科;三萜皂甙
中图分类号:R914　　　文献标识码:A　　　文章编号:0577-7496(2000)03-0306-05
New Triterpenoid Saponins from Polycarpon prostratum (Caryophyllaceae)
DING Zhong_Tao1 , 2 , ZHOU Jun1＊ , HE Yi_Neng1 , DAI Hao_Fu1 , TAN Ning_Hua1
(1.Laboratory of Phytochemistry , Kunming Institute of Botany , The Chinese Academy of Sciences , Kunming 650204, China;
2.Department of Chemistry , Yunnan University , Kunming 650091 , China)
Abstract:　Three new triterpenoid saponins , namely prostratosides A-C (1-3), were isolated from the
whole plant of Polycarpon prostratum (Forssk.)Aschers.et Schwein.ex Aschers.By spectroscopic methods ,
their structures were determined as 3_O_{β_D_xylopyranosyl_(1※2)_β_D_glucopyranosyl_(1※4)_[ β_D_glu-
copyranosyl_(1※2)]_α_L_arabinopyranoside}_22α_acetoxy_saikogenin G , 3_O_{β_D_xylopyranosyl_(1※2)_β_
D_glucopyranosyl_(1 ※4)_[ β_D_glucopyranosyl_(1 ※2)]_α_L_arabinopyranoside}_16α_hydroxy_22α_acetoxy_
saikogenin E and 3_O_{β_D_xylopyranosyl_(1※2)_β_D_glucopyranosyl_(1※4)_[ β_D_glucopyranosyl_(1※2)]_
α_L_arabinopyranoside}_21β_acetoxy_saikogenin G , respectively.
Key words:　Polycarpon prostratum;Caryophyllaceae;triterpenoid saponin
　　 Polycarpon is a genus of Caryophyllaceae consisting
of 16 species.Some phytochemical researches on this
genus have been published[ 1-2] .Polycarpon prostratum
(Forssk.)Aschers.et Schwein.ex Aschers is a small
annual herb growing at the river side and road sides in
damp soil.It is said to be toxic and has anti_inflammatory
and anodyne activities[ 3] .Our investigation on the
n_BuOH soluble fraction of this whole plant led to the iso-
lation of three new saikosaponin_like compounds , namely
prostratosides A-C(1-3).We report herein the isola-
tion and structure elucidation of these three compounds.
1　Results and Discussion
The HRFABMS of prostratoside A(1)gave a [M-
1] - ion at m/ z 1 117.550 5 , in agreement with the
molecular formula C54H86O24(calcd for C54H86O24 m/ z
1 117.543 1).The IR spectrum showed absorption bands
at 3 371 , 1 717 , 1 646 and 1 046 cm-1.The 1H-NMR
spectrum exhibited the presence of four anomeric protons
atδ4.92(d , J =7.2 Hz), 4.98 (d , J =8.0 Hz),
5.02(d , J =6.0 Hz)and 5.49(d , J =8.0 Hz).The
13C-NMR spectrum showed four anomeric carbon reso-
nances atδ103.9 , 104.2 , 105.1 and 107.6.Correla-
tions between anomeric carbon resonances and anomeric
proton signals were also observed in HMQC spectrum.
This information suggested that compound 1 is a tetragly-
coside.
The 1H-NMR spectrum exhibited the presence of six
angular methyl groups at δ0.95 , 0.98 , 1.01 , 1.09 ,
1.30 and 1.61 , and two olefinic methines atδ6.00(d ,
J =10.2 Hz), 5.65(dd , J =10.4 , 2.8 Hz).In the
Received:1999-07-07　Accepted:1999-12-07
Foundation item:A grant(9911143)from the Education Commission of Yunnan Province , China.
＊Author for correspondence.
植　物　学　报　2000 , 42(3):306-310 　 　 　 　 　 　 　

Acta Botanica Sinica
13C-NMR andDEPT spectra , two olefinic signals were ob-
served atδ132.6 and 131.5 corresponding to two me-
thine carbons C_11 and C_12.One methylene carbon (δ
76.8 , C_28)and one quaternary carbon(δ84.9 , C_13)
were also seen.This information suggested that the agly-
cone of compound 1 is a saikogenin_like compound.A
correlation in HMQC spectrum between a 13C_NMR signal
atδ21.1 and a 1H-NMR resonance atδ2.01(s)and a
correlation in the HMBC spectrum between signals at δH
2.01 andδC 170.7 confirmed the presence of one acetoxy
group in the molecule.A comparison of compound 1 with
22α_hydroxy_saikogenin G[ 4] showed that the 13C_NMR
data of the aglycones of these two compounds are very
similar , except for C_22 (δ77.1), C_21(δ42.2)and
C_17(δ49.6)which showed shifts +2.8 , -3.5 and
+2.1 , respectively , indicating that acetoxy group was
attached to C_22.The HMBC correlation between the
C O of the acetoxy group and H_22 gave further con-
firmation.The 1H_NMR signal of H_22 (δ5.29 , dd , J
=12.0 , 5.5 Hz)suggested H_22 to be an axial H.The
NOE were observed between H_22 and H_30 (δ0.98),
and H_22 and H_28 (δ3.68 , 3.78), that also showed
the orientation of H_22 to be in β_position.C_16 (δ
71.0)and C_28 were at relative low field , indicating the
presence of an α_OH was at C_16[ 5] .Therefore , the
structure of the aglycone was determined as 22α_acetoxy_
saikogenin G.
The sugar units of compound 1 were established as
arabinose , xylose , glucose by TLC comparing with au-
thentic samples.The common D configuration for xylose
and glucose , and L configuration for arabinose were as-
sumed according to those most often encountered among
the plant glycosides.The sequence of monosaccharide
units , interglycosidic linkages and anomeric configurations
were determined by spectral analysis , including FABMS ,
1H-NMR , 13C_NMR , HMQC , HMBC and HMQC_
TOCSY.The FABMS(negative_ion mode)gave four frag-
ments(m/z 986 [M-pentose] - , 956 [M-glc] - , 823
[M-pentose-glc-H] - , 661[M -pentose-glc-glc
-H] -), indicating that a pentose and a glucose were
terminal sugars.By analysis of HMQC_TOCSY and HM-
BC spectra , the 1H and 13C_NMR signals of the sugar
moieties could be assigned.The HMBC correlations were
observed between C_3(δ82.4)of the aglycone and H_1
(δ5.02)of arabinose , C_2(δ80.4)of arabinose and
H_1(δ5.49)of glucose1 , C_4 (δ78.2)of arabinose
and H_1(δ4.98)of glucose2 , and C_2(δ85.3)of glu-
cose2 and H_1(δ4.92)of xylose (Fig.1).Therefore ,
the sequence of these sugars could be determined.All the
carbon signals due to these sugar moieties were in good
agreement with the published data for similarly linked
sugar moieties[ 6 ,7] .β_Configuration at the anomeric posi-
tions may be inferred from the values of the coupling con-
stants for both glucopyranosyl units(J =8.0 Hz)and xy-
lopyranosyl unit (J =7.2 Hz).The configuration and
ring size of the arabinosyl unit were less clear.The value
of its coupling constant(J =6.0 Hz)is midway between
that observed for methyl β_L_arabinofuranoside (J =4.0
Hz)andmethylα_L_arabinopyraoside(J =8.0 Hz).Ac-
cording to the references[ 7 , 8] , the coupling constant ob-
served in compound 1 is consistent with anα_L_arabinopy-
ranoside moiety in a conformational equilibrium (4C1 and
1C4).
On the basis of the above results and the assumption
that xylose and glucose are members of the commonly
found D series and arabinose of the L series , prostratoside
A (1)was identified as 3_O_{β_D_xylopyranosyl_(1※2)_
β_D_glucopyranosyl_(1 ※4)_[ β_D_glucopyranosyl_(1 ※
2)]_α_L_arabinopyranoside}_22α_acetoxy_saikogenin G.
Prostratoside B(2)exhibited four fragments at 1 101
[M-1] - , 969 [ M_pentose -H] - , 939 [ M -glc -
H] - , and 807 [M-pentose-glc-H] - in the negative
FABMS .The information obtained from FAB_MS , 13C ,
Fig.1.　Selected HMBC correlation of prostratoside A.
3 期 丁中涛等:多荚草中的新三萜皂甙(英) 307　
1H NMR and DEPT spectra implied a C54H86O23molecular
formula.A comparison with compound 1 showed that
compound 2 had the same sugar moiety at C_3 as com-
pound 1 and structural similarity in the aglycone moiety.
The main difference was at C_23 , which was a methyl
carbon signal ofδ28.0 in compound 2 , but a methylene
in compound 1.And the signals atδ16.4 , 39.1 , 26.6 ,
89.2 , 40.2 , 55.6 , 18.1 and 32.0 were assigned to C_
24 and C_1 through C_7 respectively , which were also dif-
ferent from that of compound 1.These facts indicated the
aglycone of compound 2 to be 16α_hydroxy_22α_acetoxy_
saikogenin E.Therefore , the structure of prostratoside B
(2)was assigned as 3_O_{β_D_xylopyranosyl_(1※2)_β_
D_glucopyranosyl_(1※4)_[ β_D_glucopyranosyl_(1※2)]_
α_L_arabinopyranoside}_16α_hydroxy_22α_acetoxy_saiko-
genin E.
Prostratoside C (3)revealed the same ion peaks at
m/z 1 118 [M] - , 986 [M -pentose] - , 956 [M -
glc] - , 823 [M-pentose-glc-H] - as compound 1 in
the negative FABMS.A 13C_NMR spectral comparison of
compound 3 with compound 1 showed that compound 3
had the same sugar moiety as compound 1 , and was simi-
lar structurally to compound 1 in rings A-D of the agly-
cone , varying only in the E ring of the aglycone.The two
methyl carbon signals assigned to C_29(δ30.0)and C_
30(δ19.5)were shifted upfield by 3.42 and 5.75 , re-
spectively , when compared with compound 1 , which sug-
gested the presence of an acetoxy function at C_19 or C_
21[ 9] .Comparing compound 3 with saikosponin D[ 4]
showed that C_22(δ36.5), C_17(δ48.0)and C_20(δ
36.0)of compound 3 changed shifts(+5.3 , +2.5 and
+4.2 , respectively) and the C_18 (δ50.6) only
changed by -0.92 , suggesting the acetoxy function to be
at C_21 (δ77.9).The HMBC spectrum exhibited the
correlations between H_21 and C O (OAc , δ171.
0), H_21 and C_30 , which gave further confirmation.
The 1H_NMR signal of H_21(δ6.10 , dd , J =11.2 , 5.
2 Hz)showed the presence of an axial proton at C_21.
Consequently , the structure of prostratoside C (3)repre-
sented as 3_O_{β_D_xylopyranosyl_(1※2)_β_D_glucopyra-
nosyl_(1 ※4)_[ β_D_glucopyranosyl_(1 ※2)]_α_L_ara-
binopyranoside}_21β_acetoxy_saikogenin G.
Triterpenoid saponins isolated from the plants be-
longing to Caryophyllaceae are mainly glycosides of gypso-
genin , gyposgenic acid , quillaic acid , hederagenin or
medicagenic acid having different sugar moieties.Saikos-
aponins , with different combinations of glucose , rhamnose
and fucose as sugar moieties , are prominent in Bupleurum
species(Umbelliferae)[ 5] , and are also found in plants of
the genus Clinopodium (Labiatae)[ 9] .Some of them were
reported to have antiviral , anti_inflammatory , haemolytic
and plasma_cholesterol lowering activities.It is notewor-
thy that saikosaponin_like compounds with an 11_ene and
a five_membered ether ring in the aglycone moiety , and
arabinose , glucose and xylose as sugar moiety , were iso-
lated from Caryophyllaceae for the first time.
2　Experimental
2.1　General experimental procedures
Melting points were determined on Kofler block and
uncorrected.Optical rotations were measured with a
SEPA_300 polarimeter.IR spectra were measured on a
Bio_Rad FTS_135 spectrometer.NMR spectra were ob-
tained on Bruker AM_400MHz and DRX_500 MHz spec-
trometers.A VG Auto Spec_3000 spectrometer was used
to record FABMS spectrum.200-300 mesh and 300-
400 mesh silica gel , D_101 resin and RP_18 were used
for column chromatography.
2.2　Plant material
The whole plants of Polycarpon prostratum
(Forssk.)Aschers.et Schwein.ex Aschers were collect-
ed in Xishuangbanna , Yunnan province , China , in July
1997.The botanical identification was made by senior en-
gineer Hong Wang , Xishuangbanna Tropical Botanical
Garden , the Chinese Academy of Sciences.
2.3　Extraction and isolation
The plant material(6.0 kg)was extracted with hot
ethanol four times to afford an EtOH extract that was sus-
308　 植　物　学　报　　Acta Botanica Sinica 42 卷
Table 1　13C_NMR data for prostratosides A-C in C5D5N(100MHz)
Position A B C Position A B C
Aglycone moiety Sugar moiety
1 38.7 39.1 38.7 Ara
2 25.9 26.6 26.0 1 103.9 104.3 104.0
3 82.4 89.2 82.5 2 80.4 80.0 80.3
4 43.9 40.3 43.7 3 73.5 73.5 73.5
5 47.9 55.6 47.9 4 78.2 78.1 78.1
6 17.7 18.1 17.8 5 64.4 64.6 64.8
7 31.7 32.0 31.8 Glc1
8 42.2 42.3 42.1 1 105.1 105.0 105.0
9 53.1 53.0 53.1 2 76.3 76.3 76.3
10 36.4 36.5 36.5 3 78.5 78.8 78.6
11 132.6 132.6 132.6 4 71.7 72.1 71.8
12 131.5 131.6 131.6 5 78.4 78.3 78.4
13 84.9 85.0 84.9 6 62.9 63.2 63.0
14 44.2 44.3 44.0 Glc2
15 35.3 35.3 35.2 1 104.2 104.9 104.2
16 71.0 70.9 70.9 2 85.3 85.3 85.3
17 49.6 49.7 48.0 3 77.7 77.6 77.7
18 51.1 51.1 50.6 4 71.2 71.3 71.3
19 37.6 38.3 38.4 5 78.4 78.3 78.4
20 33.3 33.4 36.0 6 62.5 62.5 62.5
21 42.2 42.3 77.9 Xyl
22 77.1 77.4 36.5 1 107.6 107.6 107.6
23 64.8 28.0 64.8 2 76.1 76.1 76.1
24 13.0 16.4 13.0 3 77.9 77.9 77.9
25 18.9 18.6 18.8 4 70.9 70.9 70.9
26 19.7 19.7 19.7 5 67.6 67.6 67.6
27 18.2 18.4 18.2
28 76.8 77.1 76.9
29 33.4 33.5 30.0
30 25.2 25.3 19.5
OAc 170.7 170.9 171.0
21.1 21.1 21.4
pended in water , and extracted with ethyl acetate and
n_butanol , respectively.The n_BuOH residue (40.0 g)
was chromatographed on D_101 resin with a H2O_EtOH
gradient system (1∶0※0∶1).The fraction eluted with
70%MeOH was further subjected to silica gel (CHCl3∶
MeOH=7∶3)and RP_18(MeOH∶H2O =7∶3)column
chromatography to afford prostratosides A (1 , 120 mg ,
0.001 8%), B(2 , 40 mg , 0.000 6%)and C (3 , 60
mg , 0.001 5%), respectively.
2.4　Identification
Prostratoside A (1)　White powder.mp 250 -
252 ℃.[ α] 24D +4.3°(c =0.88 , MeOH).IR νKBrmax
cm
-1:3 371 , 1 717 , 1 642 , 1 046.FABMS m/ z:1 118
[M] -(100), 986(22), 956(7), 823(12), 661(2);
HRFABMS:[ M-1] - at m/z 1 117.550 5 (calcd for
C54H86O24 , 1 117.543 1).1H-NMR (C5D5N , 400
MHz):δ0.98 (3H , s ,H_30), 1.01 (3H , s , H_29),
1.09 (3H , s , H_24), 0.95 (3H , s , H_25), 1.61
(3H , s , H_27), 1.30(3H , s , H_26), 2.01(3H , s ,
H_OAc), 6.00 (1H , d , J =10.2 Hz , H_11), 5.65
(1H , dd , J =10.4 , 2.8 Hz , H_12), 5.29(1H ,dd , J
=12.0 , 5.5 Hz , H_22), 5.02(1H , d , J =6.0 Hz ,
H_1ara), 5.49 (1H , d , J =8.0 Hz , H_1glc1), 4.98
(1H , d , J =8.0 Hz , H_1g lc2), 4.92(1H , d , J =7.2
Hz , H_1xyl).13C_NMR data , see Table 1.
Prostratoside B(2)　White powder.C54H86O23.
mp 235-238 ℃.[α] 25D +4.9°(c=0.46 , MeOH).IR
νKBrmax cm-1:3 420 , 1 721 , 1 646 , 1 082.FABMS m/z:
1 101 [M-1] -(100), 969(23), 939(4), 807(12).
1
H-NMR(C5D5N , 400 MHz):δ5.97 (1H , d , J =
10.8 Hz , H-11), 5.65(1H , dd , J =10.4 , 2.8 Hz ,
H_12), 5.24 (1H , dd , J =11.2 , 5.2 Hz , H_22),
4.97(2H , d , J =7.6 Hz , H_1ara , H_1glc2), 5.48
(1H , d , J =7.6 Hz , H_1glc1), 4.94(1H , d , J =7.2
3 期 丁中涛等:多荚草中的新三萜皂甙(英) 309　
Hz , H_1xy l).13C-NMR data , see Table 1.
Prostratoside C(3)　White powder.C54H86O24.
mp 240-242 ℃;[α] 25D +6.7°(c=0.67 , MeOH);IR
νKBrmax cm-1:3 404 , 1 716 , 1 647 , 1 047.FABMS m/ z:
1 118 [M] -(100), 986 (9), 956 (3), 823 (3).
1
H_NMR(C5D5N , 400 MHz):6.00(1H , d , J =10.4
Hz , H_11), 5.67(1H , d , J =10.0 Hz , H_12), 6.10
(1H , dd , J =11.2 , 5.2 Hz , H_21), 5.00(1H , d , J
=5.8 Hz , H_1ara), 5.48 (1H , d , J =8.0 Hz , H_
1g lc1), 4.95(1H , d , J =7.6Hz , H_1glc2), 4.91(1H ,
d , J =7.2 Hz , H_1xyl).13C_NMR data , see Table 1.
References:
[ 1 ] 　Meselhy M R , Aboutabl E_S A.Hopane_type saponins from
Polycarpon succlentum growing in Egypt.Phytochemistry ,
1997 , 44:925-929.
[ 2] 　Bhandari S P S , Agrawal P K , Garg H S.A triterpenoid
saponin from Polycarpon leflingiae.Phytochemistry , 1990 ,
29:3889-3892.
[ 3 ] 　Li Y_H(李延辉).List of Plants in Xishuangbanna.Kun-
ming:Yunnan Ethnic Press , 1996.107.(in Chinese)
[ 4] 　Gong Y_H(龚运淮).13C_NMR Data of Natural Products.
Kunming:Yunnan Science and Technology Press , 1986.
135-136.(in Chinese)
[ 5 ] 　Jia Q(贾琦), Zhang R_Y(张如意).Progress in the
chemistry of saponins from the plants of the genus Buplen-
rum.Acta Pharm Sin(药学学报), 1989 , 24:961-971.
(in Chinese)
[ 6] 　Shoji N , Umeyama A , Yoshikawa K , Arihara S.Structures
of anagallosaponins Ⅰ -Ⅴ and their companion substances
from Anagllis arvensis L.Chem Pharm Bull , 1994 , 42:
1750-1755.
[ 7] 　Waltho P J , Williams D H , Mahato S B , Pal B C , Barna J
C J.Structure elucidation of two triterpenoid tetrasaccha-
rides from Androsace saxifragifolia.J Chem Soc Perkin
Trans I , 1986 , 1527-1531.
[ 8] 　Tommasi N D , Piacente S , Gacs_Baitz E , Simone F D ,
Pizza C , Aquino R. Triterpenoide saponins from
Spergularia ramosa.J Nat Prod , 1998 , 61:323-327.
[ 9] 　Miyase T , Matsushima Y.Saikosaponin homologues from
Clinopodium spp.Chem Pharm Bull , 1997 , 45:1493 -
1497.
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310　 植　物　学　报　　Acta Botanica Sinica 42 卷