全 文 ：波 谱 学 杂 志第 24卷第 2期
2007年 6月　 Chinese Journal of M agnetic Resonance
Vo l.24 No.2
　 Jun.2007
Article:1000-4556(2007)02-0141-06
Structure Determination of a Sesquiterpene Lactone
Isolated from Nouelia Insignis Franch by 2D NMR
HU X iao-yu1 , 2 , WU X in-wei 1 , MEI Na 1 , ZHOU Le 1＊
(1.Northw est A&F Universi ty , Yang ling 712100 , Chin a;
2.Chengdu Inst itute of Biology , the Chinese Academy of S ciences , C hengdu 610041 , China)
Abstract:A sesquiterpene lactone w as isolated f rom Nouelia insignis F ranch , and its structure
was elucidated(compound 1)by 2D NM R to be 8β , 9-dihydro-ono se rio lide.Complete assign-
ment of the 1H and 13C chemical shifts for the compound was obtained.The assignments of H-
1 and H-2 of the compound previously repo rted w ere found inco rr ect , and the co r rect assign-
ments we re given.The results of this study may have some practical significance fo r the st ruc-
tur al elucidation o f onoseriolide sesquiterpene lactones.
Key wo rds:NMR , chemical shif t assignment , onoseriolide , Nouelia insi gnis F ranch
CLC number:O641　　Document code:A
Introduction
Nouelia insignis Franch , an endemic plant and a mono type species of the genus
Nouelia Franch , is only conf ined to Sichuan and Yunnan region , especially to Panzhihua
Ci ty in China
[ 1] .The genera Nouelia and Leucomeris(Compositae)are cy tolo gically re-
lated.Nouelia may be descendant of old plants , which w as developed as an o rnamental
plant in Peoples Republic of China.Leucomeris Kurz , a sibling genus of Nouelia
Franch , was used as anti-inf lammatory medicinal herb to cure cough and snake bite[ 2 , 3] .
The phy tochemical investigat ion on N.insignis has not been reported previously.Our
recent phytochemical inve stig ation on N.insignis has resulted in the isolat ion of a ses-
quiterpene lactone 8β , 9-dihydro-onoseriolide(compound 1)fo r the first time.8β , 9-di-
Received date:Sept.5 , 2006;Revised date:Nov.29 , 2006
Biography:Hu Xiao-yu(1981-), f email , Shijiazhuang , Hebei , C hina , Master of phytochemist ry.　＊C orrespon ding
au th or:Zhou Le , Tel:029-87092048 , E-mail:bet terzl@163.com .
hydro-onose rio lide , a eudesmanolide w ith a cyclopropane ring , was only iso lated from
wunderl ichiam irabi li s in 1980
[ 4] , how ever , there have been no studies on its NMR sig-
nals assignment by 2D NMR.Thus , in this study , the 1H NMR and 13C NM R chemical
shif ts of this compound were assigned using bo th 1D NMR and 2D NMR techniques , in-
cluding 1H NMR , 13C NMR , HSQC , HMBC and NO ESY.The present paper describes
the isolation and st ructure elucidat ion of this compound , and furthermo re cor rected an
e rror on the assignment of H-1 and H-2 reported in the lite ra ture.
1　Experimental
1.1　Plant material
The aerial par ts of N .insignis were collected in Yanbian County , Panzhihua City
of Sichuan Province in M ay 2004 and ident ified by Prof.Fading Fu in Chengdu Institute
of Bio logy , the Chine se Academy of Sciences(CAS).A voucher specimen(A-182)was
depo sited at the Herbarium of Chengdu Institute of Biology , CAS.
1.2　Instruments
The 1D , 2D NMR spect ra w ere recorded on a Bruker Avance 600 spect rometer wi th
TM S as an inte rnal standard and CDCl3 as so lvent.Mass spectrum was obtained on a
Finnig an-LCQDECA mass spect rome ter (ESI-MS)and a Bruker Dal tonics Bio-TOF-Q
mass spect romete r(HRESIM S).The 1H and 13C NM R spect ra w ere operated at 600.13
MHz and 150.92 MHz respectively , and co rresponding standard pulse sequences w ere
given in the gHSQC , and gHMBC experiments , mean while , the NOESY spect ra w ere
operated w ith sweep widths o f 7 183.908 Hz in F1(1H)dimension and 7 183.908 Hz in
F2(1H)dimension respectively , and the pulse inte rv als D1 w ere 1.5 s and 2.0 s , the ac-
quisi tion times(N S)were 4 and 8 respect ively too.The gHSQC and gHMBC spectra
were recorded at the conditions w ith sw eep w idths of 7 183.908 Hz in F1(1H)dimen-
sion and 31 746.031 Hz in F2(13 C)dimension respectiv ely , at the same t ime the gHSQC
experiment w as performed at pulse interval D1 of 2.5 s , 13C-1H coupling constant 140
and N S o f 4.In addi tion , the gHMBC expe riment w as performed at pulse intervalD 1 of
2 s , the 13C-1H long-range coupling constant of 8 Hz , the 13 C-1H long-range coupling
signals and N S of 32.
1.3　Extraction and isolation
The air-dried and powdered aerial par t of N.insignis(4.5 kg)was macerated wi th
95% ethanol(25 L×3 , each 7 d)at ro om temperature.The solvents w ere removed un-
der reduced pressure to give 354 g residue , which w as suspended in H 2O (1.5 L)and
then par titio ned successively w ith pet roleum ethe r(60 ～ 90°C , 1.5 L×4), ethy l acetate
(1.5 L×8)and n-butano l(1.5 L×5)to af fo rd co rresponding fractions A (34.3 g), B
(56.5 g), and C (114.5 g).Fraction A w as subjected to column chromato graphy on
MCI gel( 5×L 60 cm , 50 g)eluted w ith M eOH-H 2O(3∶2 , 7∶3 , 4∶1 , 9∶1 , 19∶
1 , 1∶0 , V/V , each 1.0 L)to yield six subfractions A1 ～ A 6.Compound 1(6 mg)was
142 波　　谱　　学　　杂　　志　　　　　　　　　第 24卷　
obtained from A 1(1.3 g)separated by co lumn chromato graphy on si lica gel( 2×L 25
cm , 40 g)eluted w ith pet roleum ethe r-acetone (10∶1 , V/V).
2　Results and Discussion
Compound 1 was obtained as w hite crystal w ith m .p.174 ～ 176 ℃ f rom the mix-
ture of petro leum e ther and acetone.Four teen peaks f rom eighteen protons (1H)and
fif teen peaks(13C)were observed in the 1H and 13C NMR spectra , respectively w hich
w as in accordance wi th it s molecular formula C15H 18O 3 derived f rom the quasi-molecular
ion peak at m/z 269.099 2 [ M +Na] + in the H R-ESIM S.The IR peaks at νmax 3 480 ,
1 748 , 3 055 and 895 cm-1 show ed the presence of hydroxy l g roup , carboxyl group and
exo-methy lene.From the molecular fo rmula and 1H and 13C NMR data(Table 1), one
hydro xy l g roup , one lactone g roup(δC 173.7)and an exo-methy lene(δH 5.02 brs , 4.75
brs;δC 106.4)could be concluded.Therefo re , compound 1 should be a sesquite rpene
lactone.
Fig.1　The main correlat ion in the HMBC of compound 1 　Fig.2　The major NOE correlation of comp ound 1
The
1
H NMR spectrum of compound 1 in CDCl3 show ed the signal fo r one methy l
group atδH 0.78(s , 3H), toge ther w ith tw o exo-methylene protons at δH 5.02 and 4.75
(each 1H , br.s);i rradiation o f the broadened sing let at δH 1.97 changed the signals at
δH 1.38 , 0.91 , 0.83 and co llapsed the signals of the exo-methylene protons(H-15)to
doublets , clearly indicating that these signals were those of the cyclopropane ring .In
addit ion , the 13C NM R spect rum revealed one methy l signal at δC 17.3 , signals of a cy-
clopropane ring at δC 26.8 , 15.9 and 23.5 , tw o exo-methy lene carbon at δC 106.4 and
149.9 , tw o double-bond carbon signals at δC 164.5 and 124.1 , and one w eak carbon sig-
nal of ca rbonyl g roup at δC 173.7 , which confi rm a tricyclic sesqui terpene having the lin-
denane carbon skele ton for compound 1.Moreover , comparison of the 13C NMR of com-
pound 1 w ith that of onoseriolide
[ 5]
show ed that compound 1 was obviously closely relat-
ed to that of ono serio lide.However , in the 1H NMR spectrum the presence of a double
doublet at δH 5.10 (dd , J 1 =7.0 , J 2 =10.7), which w as coupled w ith tw o further
double doublets , showed that the 8 , 9-double bond in onoserio lide w as hydrogenated.
All the
1
H NMR data(Table 1)fully testified this assumption.The full assignments of
143
　第 2期　　HU Xiao-yu et al:Structure Determina tion of a Sesquiterpene Lactone
I so lated from Nouelia Insignis F ranch by 2D NMR
pro ton and carbon signals and the stereochemist ry of compound 1 were based on the a-
nalysis o f
1
H NM R , 13C NMR , HSQC , HMBC and NO ESY spect ra(Table 1).
Table 1　1H and 13CNMR data of compound 1(CDCl3)
No.
C　H
H SQC
δH　　　　　　J/Hz　　 　　　　δC
HMBC
1 1 1.38 (td , J 1=3.7 , J 2=7.6) 26.8 0.78(H-14), 1.58(H-9β)
2
2α
2β
0.83
0.91
(dd, J 1=3.7 , J2 =8.7)
(dd, J 1=3.7 , J2 =8.7) 15.9 0.78(H-14)
3 3 1.97 (br.s) 23.5 5.02 , 4.75(H-15 , H-15′), 0.91 , 0.83(H-2α, H-2β)
4 149.9 0.91 , 0.83(H-2a , H-2β)
5 5 2.54 (dd, J 1=3.0 , J2 =13.7) 63.9 5.02 , 4.75(H-15 , H-15′), 2.11 , 2.84(H-6α, H-6β),
2.67 , 1.58(H-9α, H-9β), 0.78(H-14)
6
6α
6β
2.84
2.11
(dd, J 1=3.0 , J2 =13.7)
(t , J =13.7) 23.9
7 164.5 4.40(H-13), 2.11 , 2.84(H-6α, H-6β), 2.67(H-9α)
8 8 5.10 (dd, J 1=7.0 , J2 =10.7) 80.2 2.67 , 1.58(H-9α, H-9β), 2.84(H-6β)
9
9α
9β
1.58
2.67
(t , J =11.4)
(dd, J 1=7.0 , J2 =11.4) 43.9 5.10(H-8), 0.78(H-14)
10 38.4 0.78(H-14), 0.91 , 0.83(H-2α, H-2β), 2.67 , 1.58(H-9α, H-9β), 2.11 , 2.84(H-6α, H-6β)
11 173.7 4.40(H-13)
12 124.1 4.40(H-13), 2.11 , 2.84(H-6α, H-6β), 5.10(H-8)
13 13 4.40 (2H , d , J =3.5) 54.8
14 14 0.78 (3H , s) 17.3 2.67 , 1.58(H-9α, H-9β)
15
15
15′
5.02
4.75
(br.s)
(br.s) 106.4
＊d:doublet;dd:doublet-d oub let;td:t riplet-doub let;s:singlet;b r.s:b road singlet.
In the HSQC spectrum , δH 1.38(td , J 1=3.7 , J 2=7.6 , H-1)was connected wi th
δC 26.8 , δH 0.91 (dd , J 1=3.7 , J 2=8.7 , H-2α)and δH 0.83(dd , J 1 =3.7 , J 2=8.7 ,
H-2β)both we re connected w ith δC 15.9 , δH 1.97 (br.s , H-3)was connected w ith δC
23.5;the above all also suggested the presence of the signals of a cyclopropane ring ,
and gave the exact assignment of each proyon.Howeve r , from this experimental conclu-
sion w e found that there w as an er ror in the at t ribution of H-1 and H-2 reported in the
literature , in w hich δH 0.83 w as at t ributed to be H-1 , but it should be H-2β , δ0.91 and
1.38 w ere at t ributed to be H-2αand 2β , but they should be H-2αand H-1.So we co r-
rected the se error s in o rder to afford the co rrect complete assignment of the
1
H and
13
C
chemical shi ft s fo r this compound and provide some pract ical significance fo r the st ruc-
144 波　　谱　　学　　杂　　志　　　　　　　　　第 24卷　
tural elucidation of ono seriolide sesquite rpene lactones.
In the HMBC spect rum , a cross peak of 1H-13C long-range coupling w as observed
between the exo-methy lene pro ton signals at δ5.02 and 4.75 (H-15 and 15′)and the
carbon signals at δ63.9(C-5)and 23.5(C-3), respectively w hich indicats that the exo-
methy lene w as located a t C-4(δ149.9).The ter tiary methy l was located at C-10 from
the HMBC co rrelations(Fig .1)f rom H-14(δ0.78 , 3H , s)to C-1 (δ26.8), C-9 (δ
43.9)and C-5(δ63.9).The HMBC co rrelations f rom H-13 (δ4.40 , 2H , d , J =3.5)
to C-7 (δ164.5), C-12(δ124.1)and C-11(δ173.7)suggested tha t the hydroxy l g roup
w as at C-13.T he de tailed interrelations be tw een 1H-13 C fo r the sesquiterpene po rtion
are show n in Fig .1 and Table 1.
The stereochemist ry o f compound 1(Fig.2)was revealed by the NOESY spect rum
in which NOEs w ere observed betw een H-1 and H-2α, H-3 and H-2α.Therefo re , H-1
and H-3 both w ere αconfiguration , which w as also identical to that in ono seriolide re-
po rted in the li terature[ 5] .In the NOESY spect rum , there w as cor relat ion betw een H-8
and H-14 CH3 , but NOE betw een H-14 CH 3 and H-1 w as not obse rved.This indicated
that the stereochemistry of H-8 and H-14 CH 3 were the same but opposi te to H-1 , so
bo th o f them we re β configuration.The detai led NOESY correlations of o ther protons of
this sesquiterpene lactone are as show n in Fig.2.Therefore , compound 1 , iso lated from
Nouelia insignis Franch for the f rist time , was determined to be 8β , 9-dihydro-ono seri-
o lide.
References:
[ 1] 　In sti tu te of Botany , C hinese Academy of Sciences(中国科学院中国植物志编辑委员会).Flora Reipu blicae Pop-
ulari s Sinicae(中国植物志)[ M] .Beijing(北京):Science P ress(科学出版社), 1997.72-73.
[ 2] 　Lin Y R(林有润).On the p rimary s tudy of the sy stemat ics and f loris ti cs of composi tae f rom china(中国菊科植
物的系统分类与区系的初步研究)[ J] .Bu lletin of Botanical Research(植物研究), 1997 , 17(1):6-27.
[ 3] 　Peng Y L , Sun H , Gu Z J.Cy tological s tudy on Nouelia and Leucomer is(Compositae)[ J] .Acta Bot Yunnan ,
2002 , 24(1):82-86.
[ 4] 　Boh lmann F , Zdero C , Robinson H , et al.Modified eudesmanolides and other sesquiterpene lactones f rom
Wunder lichia mirabi li s and Actinoser is polymorpha[ J] .Phytochemis try , 1981 , 20:1 631-1 634.
[ 5] 　Bohlmann F , Zdero C , King R M.et a l.Onoseriolid , ein n eues sesquiterpenlacton aus Onoseri s albicans[ J] .
Phy toch emist ry , 1980 , 19:689-691.
145
　第 2期　　HU Xiao-yu et al:Structure Determina tion of a Sesquiterpene Lactone
I so lated from Nouelia Insignis F ranch by 2D NMR
2D NMR对栌菊木中的一个倍半萜内酯进行结构解析
胡晓玉1 , 2 ,吴新卫1 ,梅　娜1 ,周　乐1＊
(1.西北农林科技大学 , 陕西 杨凌 712100;2.中国科学院 成都生物研究所 , 四川 成都 610041)
摘　要:通过核磁共振对一个首次从菊科单种属植物-栌菊木中分离得到的乌药烷型倍
半萜内酯-8β , 9-dihydro-ono serio lide进行了结构解析 , 通过 2D NMR(HSQC , HMBC ,
NOESY)首次对该化合物的碳和氢质子信号进行全归属;并证实其结构中的 H-1 , H-2
互为颠倒 , 纠正了文献报道中的错误 ,该研究对乌药烷骨架倍半萜内酯的结构鉴定提供
了光谱学依据.
关键词:NMR;化学位移归属;乌药烷型;栌菊木
　＊通讯联系人:周乐 , 电话:029-87092048 , E-m ail:bet terz l@163.com.
146 波　　谱　　学　　杂　　志　　　　　　　　　第 24卷