Phenylpropanoid and Iridoid Glucosides from the Whole Plant of Hemiphragma heterophyllum and Their alpha-Glucosidase Inhibitory Activities

Article abstract of DOI:10.1055/a-1081-7220

Three phenylpropanoid glucosides (1 ?-? 3) and one iridoid glucoside (11), together with eleven known glucosides, were isolated from the ethanol extract of the whole plant of Hemiphragma heterophyllum. Their structures were elucidated by means of 1D and 2D NMR spectroscopy, HRMS, and chemical methods. All compounds except 11 and 13 ?-? 15 showed varying degrees of α -glucosidase inhibitory activity. Compounds 5, 9, and 12 were marginally active in the bioassay, while compounds 1 ?-? 4, 6 ?-? 8, and 10 exhibited appreciable inhibitory activity with an IC ₅₀ value of 33.6 ~ 83.1 μM, which was much lower than that of the positive control acarbose (IC ₅₀ = 310.8 μM).

Full text of DOI:10.1055/a-1081-7220

Published online: 09.01.2020
Original Papers
Phenylpropanoid and Iridoid Glucosides from the Whole Plant
of Hemiphragma heterophyllum and Their alpha-Glucosidase
Inhibitory Activities
Authors
Yan-Hong Li, Jia-Meng Dai, Cui Yang, Meng-Yuan Jiang, Yong Xiong, Yu-Kui Li, Hong-Rui Li, Kai Tian, Xiang-Zhong Huang
Affiliation
Correspondence
Key Laboratory of Chemistry in Ethnic Medicinal Resources,
Prof. Kai Tian
State Ethnic Affairs Commission & Ministry of Education,
Key Laboratory of Chemistry in Ethnic Medicinal Resources,
Yunnan Minzu University, Kunming, Yunnan, P. R. China
State Ethnic Affairs Commission & Ministry of Education,
Yunnan Minzu University
Key words
No. 2929 Yuehua Street, Chenggong District, Kunming,
Hemiphragma heterophyllum, Scrophulariaceae, phenyl-
Yunnan, 650504, P. R. China
propanoid glucosides, iridoid glucosides, α‑glucosidase
inhibitor activity
Phone: + 8687165952171, Fax: + 8687165910017
tiankai002@qq.com
received May 27, 2019
Supporting information available online at
revised
November 27, 2019
http://www.thieme-connect.de/products
accepted December 6, 2019
Bibliography
ABSTRACT
DOI https://doi.org/10.1055/a-1081-7220
published online | Planta Med © Georg Thieme Verlag KG
Stuttgart · New York | ISSN 0032‑0943
Three phenylpropanoid glucosides (1–3) and one iridoid glu-
coside (11), together with eleven known glucosides, were iso-
lated from the ethanol extract of the whole plant of Hemi-
phragma heterophyllum. Their structures were elucidated by
means of 1D and 2D NMR spectroscopy, HRMS, and chemical
methods. All compounds except 11 and 13–15 showed vary-
ing degrees of α-glucosidase inhibitory activity. Compounds
Correspondence
Prof. Xiangzhong Huang
Key Laboratory of Chemistry in Ethnic Medicinal Resources,
State Ethnic Affairs Commission & Ministry of Education,
Yunnan Minzu University
5
, 9, and 12 were marginally active in the bioassay, while com-
pounds 1–4, 6–8, and 10 exhibited appreciable inhibitory
No. 2929 Yuehua Street, Chenggong District, Kunming,
Yunnan, 650504, P. R. China
activity with an IC50 value of 33.6 ~ 83.1 µM, which was much
lower than that of the positive control acarbose (IC50
10.8 µM).
=
Phone: + 8687165952171, Fax: + 8687165910017
xiangzhongh@126.com
3
plants, we investigated the whole plant of H. heterophyllum. The
ethanolic extract showed a modest α-glucosidase inhibitory effect
(IC50 = 491.6 µg/mL). Fractionation of this extract afforded three
new phenylpropanoid glucosides, heterophosides A–C (1–3), and
one iridoid glucoside, piscroside D (11), together with eleven
known glucosides (▶ Fig. 1). The isolated compounds were as-
sayed for their α-glucosidase inhibitory activity using p-nitrophe-
nyl-α-D-glucopyranoside (PNPG) as a substrate.
Introduction
Hemiphragma heterophyllum Wall. (Scrophulariaceae) is distrib-
uted mainly in the rocky mountains of Yunnan province in China
[
1]. The herb is used by Yi people as folk medicine for “dispelling
wind”, “eliminating dampness”, “removing blood stasis”, and re-
lieving pain [2, 3]. Previous chemical investigations focused on
the aerial parts and revealed the presence of a series of monoter-
pene glucosides, phenylpropanoid glucosides, and flavonoid glu-
cosides [4–9]. These compounds were shown to possess diverse
activities, such as fungistatic [10], antioxidative [11, 12], neuro-
protective [13], cytotoxic [14], and anti-inflammatory [15] prop-
erties. As part of our ongoing research program to find structur-
ally diverse and biologically active compounds from medicinal
Results and Discussion
Compound 1 was isolated as an off-white amorphous powder and
had the molecular formula C23H26O9 as indicated by the quasi-
+
molecular ion in the HRESIMS at m/z 469.1470 [M + Na] (calcd.
Li YH et al. Phenylpropanoid and Iridoid … Planta Med

Original Papers
▶
Fig. 1 Structures of compounds 1–15.
4
69.1475). The IR spectrum indicated the presence of hydroxyl
ence between these two compounds was the presence of signals
for only one glucose moiety in the NMR spectra of 2. Based on
HMBC correlations from H-1′ (δH 4.35) of glucose to C-8 (δC
−
1
(
3434 cm ) and double bond functionalities (1638 and
−
1
1
1
443 cm ). The H NMR spectrum exhibited characteristic signals
for aromatic rings (two AAʼBB' systems at the δH 6.62–7.51 re-
gion), trans-olefinic protons (AB system, δH 7.66 and 6.34, both
d, JAB = 16.0 Hz), and an ethyl residue (δH 2.73, 2H, t, J = 6.7 Hz;
δH 3.66, 1H, m and 4.05, 1H, dd, J = 15.6, 6.7 Hz) at the benzylic
position. Comparing the H and 13C NMR data (▶ Table 1) with
those of osmanthuside A suggested that compound 1 consisted
of a p-coumaroyl group, a p-substituted phenylethyl alcohol moi-
ety, and a glucose residue [16]. A doublet proton resonance at δH
72.4) of the 3,4-disubstituted phenylethyl unit, and from H -6′
2
(δ 4.53, 4.40) of glucose to C-9″ (δ 169.2) of the feruloyl group,
H
C
compound 2 was determined as 2-(3-hydroxy-4-methoxyphenyl)
ethyl 6′-O-trans-feruloyl-β-D-glucopyranoside, named as hetero-
phoside B.
1
Compound 3 was also obtained as an off-white amorphous
+
powder. The quasi-molecular ion at m/z 529.1685 [M + Na] in
the positive HRESIMS was consistent with the molecular formula
C25H30O11. Careful analysis of the 1D and 2D NMR data (▶ Table
1) from 3 and 2 revealed that they were almost identical to each
other, except for the olefinic proton resonance of the feruloyl
moiety. The coupling constant of JH‑7″,H‑8″ = 12.8 Hz in 3 versus
JH‑7″,H‑8″ = 15.9 Hz in 2 suggested the presence of cis-olefinic pro-
tons in 3. On the basis of these data, the structure of heteropho-
side C (3) was elucidated as 2-(3-hydroxy-4-methoxyphenyl)ethyl
6′-O-cis-feruloyl-β-D-glucopyranoside.
4
.53 (d, J = 8.0 Hz) from the anomeric proton of glucose and the
corresponding carbon resonance at δC 102.4 (C-1′) revealed the
β-configuration of the latter. Acid hydrolysis of 1 afforded D-glu-
cose, which was identified by TLC comparison with an authentic
sample and measurement of the optical rotation value. The p-cou-
maroyl moiety was located at C-2′ of the glucose on the basis of
the strong deshielding of the H-2′ signals of the glucose unit (δH
4
9
.84, 1H, m) and the HMBC correlations (▶ Fig. 2) from H-2′ to C-
″ (δ 168.9). Compound 1 differs in this way from osmanthuside
Compound 11 was isolated as an off-white amorphous powder
C
A in that the p-coumaroyl residue is located at C-6′ [16]. Finally,
the structure of heterophoside A (1) was established as 2-(4-hy-
droxyphenyl)ethyl 2′-O-trans-p-coumaroyl-β-D-glucopyranoside.
Compound 2 was obtained as an off-white amorphous powder.
and had the molecular formula C25H32O12 as indicated by the
quasi-molecular ion at m/z 559.1591 [M + Cl] in HRESIMS. The
1H and 13C NMR spectra (▶ Table 2) revealed the presence of a
C9-type iridoid aglycone, a sugar residue, and a trans-cinnamoyl
moiety, thus indicating that compound 11 was an analog of pis-
croside B with the same molecular formula [18]. Comparison of
−
In the positive ion HRESIMS, a quasi-molecular ion peak at m/z
+
5
29.1685 [M + Na] was observed, which was consistent with the
molecular formula C25H30O11. The IR spectrum indicated the exis-
their NMR data revealed that C-10 at δ 61.5 in piscroside B was
C
−
1
tence of hydroxyl (3435 cm ) and double bond functionalities
downfield shifted to δ 64.6 in 11, while H-6′a at δH 4.44 and H-
C
−
1
1
(
1651 and 1444 cm ). The H NMR spectrum of 2 displayed aro-
6′b at δH 4.53 in piscroside B were upfield shifted to δH 3.94 and
3.68 in 11. This suggested that the esterification position of the
trans-cinnamoyl residue was changed from C-6′ in piscroside B to
matic protons at δH 6.59–7.12 (two ABX systems) and trans-ole-
finic protons at δH 7.62 and 6.38, both d, JAB = 15.9 Hz (AB sys-
tem). The NMR data (▶ Table 1) of 2 were very similar to that of
plantainoside E, except for the sugar region [17]. The major differ-
1
1
C-10 in 11. The HMBC correlation of H -10/C‑9″ and H- H COSY
2
correlations of H-7″/H-8″, H-2″/H-3″, H-6″/H-5″, and H-3″/H-4″/
Li YH et al. Phenylpropanoid and Iridoid… Planta Med

Table 1 13C (100 MHz) and H (400 MHz) NMR spectroscopic data of compounds 1–3 (δ in ppm, J in Hz) in CD3OD.
1
▶
No.
1
2
3
δC
δH
δC
δH
δC
δH
1
2
3
4
5
6
7
8
131.1
131.1
116.2
156.7
116.2
131.1
36.4
72.0
132.7
117.1
147.3
147.5
112.8
121.2
36.8
72.4
133.0
117.2
147.3
147.5
115.2
121.3
36.8
72.3
7.00 d (7.8)
6.63 d (7.8)
6.71 s
6.72 s
6.63 d (7.8)
6.65 d (8.1)
6.60 d (8.1)
2.81 t (7.5)
3.95 dd (16.7, 8.1)
3.76 m
6.67 m
7.00 d (7.8)
6.65 m
2.73 t (6.7)
2.81 m
4.05 dd (15.6, 6.7)
3.94 m
3
.66 m
3.73 m
OMe
56.5
104.6
75.1
78.0
72.0
75.4
64.8
3.74 s
56.5
104.6
75.2
78.1
72.0
75.5
64.6
3.78 s
1
2
3
4
5
6
′
′
′
′
′
′
102.4
75.3
76.3
71.8
78.2
62.7
4.53 d (8.0)
4.84 m
4.35 d (7.9)
3.27 t (8.1)
3.43 m
4.32 d (7.6)
3.23 t (8.3)
3.37 m
3.61 m
3.43 t (9.1)
3.35 m
3.40 m
3.34 m
3.57 m
3.53 m
3.92 d (11.8)
4.53 d (11.7)
4.40 dd (11.7, 6.0)
4.52 d (11.9)
4.37 dd (11.9, 5.9)
3
.73 dd (11.8, 5.3)
1
2
3
4
5
6
7
8
9
″
″
″
″
″
″
″
″
″
127.3
131.4
117.1
161.5
117.1
131.4
146.9
115.4
168.9
127.7
111.7
149.4
150.7
116.6
124.4
147.2
115.3
169.2
56.5
128.1
113.0
147.6
148.5
116.3
127.0
145.9
115.9
168.3
56.6
7.50 d (8.0)
6.85 d (8.0)
7.12 s
7.16 s
6.85 d (8.0)
7.50 d (8.0)
7.66 d (16.0)
6.34 d (16.0)
6.81 d (8.1)
7.00 d (8.1)
7.62 d (15.9)
6.38 d (15.9)
6.80 d (8.1)
7.15 m
6.89 d (12.8)
5.85 d (12.8)
OMe
3.84 s
3.89 s
H-5″ provided additional evidence (▶ Fig. 2). It should be men-
tioned that all naturally occurring 7,8-epoxy-iridoids exhibit a β-
epoxide function according to literature data [19–21]. The ROESY
spectrum (▶ Fig. 2) displayed correlations between α-oriented H-
In addition, 11 known compounds, eutigoside A (4) [23], 2-(4-
hydroxyphenyl)ethyl 6′-O-sinapoyl-β-D-glucopyranoside (5) [24,
25], grayanoside A (6) [26], bacopaside B (7) [27], osmanthuside
E (8) [28], citrusin C (9) [29], 3-methoxyl-4-O-β-D-glucopyranosy-
loxy-benzoic acid methyl ester (10) [30], globularin (12) [31],
globularicisin (13) [31], picroside I (14) [32], and iso-scrophulario-
sid (15) [33], were identified by comparing their NMR data with
literature values (▶ Fig. 1).
The isolated compounds were tested for their α-glucosidase
inhibitory activities with acarbose as the positive control. All com-
pounds except 11 and 13–15 showed varying degrees of activity
(▶ Table 3). Compounds 5, 9, and 12 were marginally active in the
bioassay, while compounds 1–4, 6–8, and 10 exhibited appreci-
able inhibition of α-glucosidase. Despite the limited number of
compounds tested here, a preliminary analysis of the structure-
activity relationship for α-glucosidase inhibitory activity was pos-
sible. The activity of compound 1 was very similar to that of com-
pound 4, indicating that changes in the glucose-coumaroyl con-
nectivity from C-2′ to C-6′ has little impact on α-glucosidase in-
7
4
(δH 3.50) and H-6 (δH 4.14), and also between H-6 and H-3 (δH
.67), H-1 (δ 5.11), H-4 (δ 1.91), indicating the coaxial α-orien-
H
H
tation of H-6, H-3, H-1, and H-4 (▶ Fig. 2). The large coupling con-
stant for H-1α (d, J = 8.6 Hz) and H-9 (d, J = 8.1 Hz), suggested that
they were trans-diaxial oriented, thus positioning H-9 in β-orienta-
tion [22]. Proton H-9 showed a strong ROESY correlation with H-5
(
6
δH 2.11), consistent with the large coupling constant between H-
α (d, J = 9.1 Hz) and H-5 (m), which confirmed the cis-junction of
the iridoid skeleton. Although no correlation was observed be-
tween the β-oriented methoxyl group (δH 3.52) and H-9β (δH
2
.49) or H-5β (δH 2.11), its β-orientation was indirectly inferred
from the ROESY correlations and J-couplings of the iridoid ring.
Thus, compound 11, named piscroside D, was determined to be
1
0-O-trans-cinnamoyl-3β-methoxy-3,4-dihydrocatalpol.
Li YH et al. Phenylpropanoid and Iridoid … Planta Med

Original Papers
▶
▶
Fig. 2 Key 2D NMR correlations of compounds 1, 2, and 11.
Table 2 13C (100 MHz) and 1H (400 MHz) NMR spectroscopic
▶ Table 3 α-Glucosidase inhibitory activities of compounds 1–15.
data of compound 11 in CD3OD (δ in ppm, J in Hz).
Name
IC50 (µM)a
No.
1
δC
96.1
δH
1
2
3
4
5
6
7
8
9
33.9 (31.9–34.9)
88.6 (85.8–91.4)
50.6 (49.4–53.7)
33.6 (30.7–35.1)
208.8 (198.9–213.7)
46.7 (43.6–49.5)
48.9 (46.7–50.1)
41.2 (40.1–42.3)
109.0 (108.0–112.1)
83.1 (82.8–86.4)
5.11 d (8.6)
4.67 d (8.9)
1.91 br d (12.4)
1.65 m
3
100.2
29.8
4
4
5
6
7
8
9
0
α
β
38.3
74.8
62.5
63.5
43.4
64.6
2.11 m
4.14 d (9.1)
3.50 br s
2.49 t (8.1)
10
11
12
13
14
15
1
4.99 d (12.7)
> 400
335.2 (332.1–337.7)
> 400
4
.22 d (12.7)
OMe
56.6
100.0
74.6
77.9
71.6
78.5
63.2
3.52 s
1
2
3
4
5
6
′
′
′
′
′
′
4.73 d (7.9)
3.18 m
> 400
> 400
3.37 m
Acarbose
310.8 (308.4–313.7)
3.27 m
a
IC50 values represent the means of three parallel measurements
3.30 m
3.94 d (11.8)
3
.68 dd (11.8, 6.2)
hibitory activity. This was corroborated by the similar potency also
observed for compounds 7 and 8 with a feruloyl group. The activ-
ity of compound 2, bearing a trans-feruloyl group at C-6′ of glu-
cose, was lower than that of 3 with a cis-feruloyl group. Moreover,
compound 6 showed lower activity than 4, implying that the ac-
tivity was weakened by the introduction of a methoxyl group at
the C-3 position. Compound 8 was slightly more potent than
compound 6, which has a hydroxyl group at the 3′-position. More
generally, the phenylpropanoid glucosides (1–10) showed stron-
ger α-glucosidase inhibitory effects than the iridoid glucosides
1
2
3
4
7
8
9
″
135.9
129.5
130.2
131.8
146.9
118.7
168.6
″, 6″
7.65 2H d (3.9)
7.43 2H m
″, 5″
″
″
″
″
7.43 m
7.74 d (16.0)
6.59 d (16.0)
(
11–15), which suggests that phenylpropanoid glucosides might
play the main role in the α-glucosidase inhibitory activity of the
ethanol extract of H. heterophyllum.
Li YH et al. Phenylpropanoid and Iridoid… Planta Med

(
58.2 mg), which was purified on a silica gel column (200–300
Material and Methods
mesh, CHCl /MeOH, 50:1, v/v), to give compound 14 (16.0 mg).
3
Subfraction IV2.4 (300 mg) was subjected to Sephadex LH-20 CC
General experimental procedures
(
CHCl /MeOH, 1:1, v/v) to provide compound 5 (6.1 mg). Sub-
3
Silica gel (100–200, 200–300 mesh; Qingdao Marine Chemical,
Inc.), MCI gel (75–150 µm; Mitsubishi Chemical Corporation), RP-
fraction IV2.5 (1.9 g) was separated by silica gel CC (200–300
mesh) with petroleum ether/acetone (5:1, v/v) to afford eight
subfractions, IV2.5.1~IV2.5.6. Compounds 6 (5.0 mg, tR 29.7 min)
and 8 (7.0 mg, tR 24.5 min) were obtained from subfraction
1
2
8 reverse-phase silica gel (40–63 µm; Merck), and Sephadex LH-
0 were used for column chromatography (CC). Semipreparative
HPLC was performed on an Agilent 1260 liquid chromatograph
equipped with an Eclipse XDB‑C18 (9.4 × 250 mm, 5 µm) column.
IR spectra were measured on a Bio-Rad FTS-135 spectrometer
with KBr pellets. UV spectra were recorded using a Shimadzu UV-
IV2.5.4 by semipreparative HPLC with MeOH/H O (43:57, v/v) at
2
a flow rate of 3 mL/min. Subfraction IV2.5.5 (185 mg) was purified
by Sephadex LH-20 CC with MeOH to yield compound 4 (8.2 mg).
Subfraction IV2.6 (2.5 g) was purified by Sephadex LH-20 CC
2
401A spectrophotometer. Optical rotations were obtained on a
(MeOH), followed by semipreparative HPLC (MeOH/H O, 47 : 53,
2
Horiba SEPA-300 high sensitivity polarimeter. NMR spectra were
recorded on Bruker AM-400 spectrometers with TMS as an inter-
nal standard. HRESIMS was measured using an Agilent 1290 UPLC/
v/v, flow rate of 3 mL/min) to give compounds 2 (11.1 mg, tR
29.1 min) and 3 (5.3 mg, tR 30.6 min). Subfraction IV2.7 (1.5 g)
was subjected to RP-18 CC (MeOH/H O, 40:60, 60:40, 80:20,
2
6
540 Q‑TOF instrument. The α-glucosidase from Saccharomyces
100:0, v/v), followed by Sephadex LH-20 CC (MeOH) to yield
cerevisiae from Sigma-Aldrich Trading Co. Ltd., acarbose from J&K
China Chemical Ltd., and PNPG from Sigma-Aldrich Trading Co.
Ltd. were used in the bioactivity assay.
compound 10 (8.9 mg). Subfraction IV (496 mg) was subjected
to Sephadex LH-20 CC with MeOH elution to yield a fraction
(95.2 mg), which was purified on semipreparative HPLC with
4
MeOH/H O (54:46, v/v) at a flow rate of 3 mL/min, to give com-
pound 13 (16.0 mg, tR 32.3 min). Subfraction IV5 (30.5 g) was
2
Plant material
Aerial parts and roots of H. heterophyllum were collected in
Chuxiong City, Yunnan province, P. R. China, in July 2016. The
plant material was authenticated by Prof. Qing-Song Yang at the
Yunnan Minzu University. A voucher specimen (No. 2016-07-23)
was deposited at the Key Laboratory of Chemistry in Ethnic Medic-
inal Resources, State Ethnic Affairs Commission & Ministry of Edu-
cation, School of Ethnomedicine and Ethnopharmacy, Yunnan
Minzu University.
chromatographed on an MCI gel column with MeOH/H O
2
(30:70, 60:40, 90:10, 100:0, v/v) to yield eight subfractions,
IV5.1~IV5.9. Compound 15 (12.0 mg, tR 35.6 min) was isolated
from subfraction IV5.5 (33.0 mg) by semipreparative HPLC with
MeOH/H O (58:42, v/v) at a flow rate of 3 mL/min. Subfraction
2
IV5.6 (408 mg) was subjected to Sephadex LH-20 CC with MeOH
to provide compound 12 (6.0 mg).
2
5
Heterophoside A (1): Off-white amorphous powder; [α]
D
− 36.8
(
3
c 0.17, MeOH); UV (MeOH) λmax (log ε): 212 (4.71), 225 (4.78),
Extraction and isolation
13 (4.86) nm; IR (KBr) υmax: 3434, 2026, 1638, 1443, 1076,
−
1
1
The air-dried whole plants (20.0 kg) of H. heterophyllum were pow-
dered and extracted three times with 95% EtOH (60 L) at room
temperature for 48 h. The three extracts were combined and con-
centrated under reduced pressure to give a sticky residue (3.8 kg).
The residue was suspended in water (4 L) and then partitioned se-
quentially with petroleum ether (6 × 5 L), EtOAc (6 × 5 L), and n-
BuOH (6 × 5 L). The EtOAc-soluble fraction (2.0 kg) was fraction-
ated in two portions on a silica gel column (100–200 mesh,
859, 546 cm ; For H NMR (CD OD, 400 MHz) and 13C NMR
(CD OD, 100 MHz) spectroscopic data, see ▶ Table 1; HRESIMS
3
3
+
m/z: 469.1470 [M + Na] (calcd. for C23H26NaO , 469.1475).
9
2
5
Heterophoside B (2): Off-white amorphous powder; [α]
D
− 34.2
(c 0.22, MeOH); UV (MeOH) λmax (log ε): 201 (5.08), 288 (4.64),
326 (4.78) nm; IR (KBr) υ : 3435, 2026, 1651, 1444, 1269,
1121, 1072, 859, 545 cm ; For H NMR (CD OD, 400 MHz) and
1
max
−
1
1
3
3
C NMR (CD OD, 100 MHz) spectroscopic data, see ▶ Table 1;
3
1
9
5 × 120 cm) eluted with a CHCl /MeOH gradient system (10:0,
:1, 8:2, 7:3, 6:4, 5:5, 0:10, v/v; collection size: 1000 mL) to
HRESIMS m/z: 529.1685 [M + Na]+ (calcd. for C25H30NaO11
529.1686).
,
3
2
5
yield five fractions (Frs I~V) after TLC analysis.
Heterophoside C (3): Off-white amorphous powder; [α]
D
− 23.5
Fraction IV (545 g), with moderate α-glucosidase inhibitory ac-
tivity (IC50 = 172.1 µg/mL), was fractionated by silica gel CC (200–
(c 0.10, MeOH); UV (MeOH) λmax (log ε): 204 (5.58), 288 (4.99),
326 (5.14) nm; IR (KBr) υ : 3431, 2027, 1657, 1442, 1270,
max
1117, 857, 545 cm ; For H NMR (CD OD, 400 MHz) and 13C
−
1
1
3
00 mesh) with CHCl /MeOH (50:1, 30:1, 10:1, 5:5, 0:1, v/v) to
3
3
provide subfractions IV ~IV . Subfraction IV (6.0 g) was sub-
NMR (CD OD, 100 MHz) spectroscopic data, see ▶ Table 1;
3
1
7
1
jected to silica gel CC (200–300 mesh, CHCl /MeOH, 50:1, v/v)
HRESIMS m/z: 529.1685 [M + Na]+ (calcd. for C25H30NaO11
,
3
to yield a fraction (310 mg), which was purified by semiprepara-
529.1687).
2
5
tive HPLC (MeOH/H O, 60:40, v/v, flow rate of 3 mL/min), to yield
Piscroside D (11): White amorphous powder; [α]
0.20, CHCl ); UV (MeOH) λ
D
− 48.3 (c
2
compound 11 (10.0 mg, t 23.7 min). Subfraction IV (38.0 g) was
(log ε): 283 (4.72) nm; IR (KBr)
max
R
2
3
−
1
chromatographed by MCI gel CC with MeOH/H O (0:100, 50:50,
υmax: 3441, 2326, 1655, 1424, 1263, 1120, 1066, 863, 544 cm ;
2
1
13
7
0:30, 90:10, 100:0, v/v) to yield eight subfractions, IV2.1~IV2.9
.
For H NMR (CD OD, 400 MHz) and C NMR (CD OD, 100 MHz)
3 3
Subfraction IV2.2 (2.2 g) was purified by Sephadex LH-20 CC
spectroscopic data, see ▶ Table 2; HRESIMS m/z: 559.1591 [M +
Cl] (calcd. for C25H32ClO12, 559.1582).
−
(
(
CHCl /MeOH, 1:1, v/v) to furnish compounds 1 (9.5 mg), 7
23.5 mg), and 9 (12.0 mg). Subfraction IV2.3 (897 mg) was sub-
3
jected to Sephadex LH-20 CC with MeOH to yield a fraction
Li YH et al. Phenylpropanoid and Iridoid … Planta Med

Original Papers
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from Neopicrorhiza scrophulariiflora and their hepatoprotective activities
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This work was financially supported by the National Natural Science
Foundation of China (NSFC No. 81960783), the Yunnan Provincial
Applied Basic Research Projects (No. 2017FD122), Training
Programs of Innovation and Entrepreneurship for Undergraduates
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