Two new amide glycosides with anti-inflammatory activity from the leaves of Streblus ilicifolius (Vidal) Corner

Article abstract of DOI:10.1080/14786419.2021.1893318

Two new amide glycosides, streblusoamides A (1) and B (2), along with 11 known compounds (3–13) were isolated from the leaves of Streblus ilicifolius. The structures of the isolates were elucidated by spectroscopic methods. All of the isolates were tested for inhibition of NO production in lipopolysaccharide (LPS)-induced RAW 264.7 cells to investigate their anti-inflammatory effects. The results revealed that compounds 1, 5 and 6 moderately inhibited the release of NO production with IC₅₀ values ranging from 50.90 μM to 64.79 μM.

Full text of DOI:10.1080/14786419.2021.1893318

Natural Product Research
Formerly Natural Product Letters
ISSN: (Print) (Online) Journal homepage: https://www.tandfonline.com/loi/gnpl20
Two new amide glycosides with anti-inflammatory
activity from the leaves of Streblus ilicifolius (Vidal)
Corner
Yan Huang, Xishan Huang, Guobiao Tian, Wenxiu Zhang, Shanshan Su, Xia
Xu, Jun Li & Buming Liu
To cite this article: Yan Huang, Xishan Huang, Guobiao Tian, Wenxiu Zhang, Shanshan
Su, Xia Xu, Jun Li & Buming Liu (2021): Two new amide glycosides with anti-inflammatory
activity from the leaves of Streblusꢀilicifolius (Vidal) Corner, Natural Product Research, DOI:
10.1080/14786419.2021.1893318
To link to this article: https://doi.org/10.1080/14786419.2021.1893318
View supplementary material
Published online: 05 Mar 2021.
Submit your article to this journal
Article views: 25
View related articles
View Crossmark data
Full Terms & Conditions of access and use can be found at
https://www.tandfonline.com/action/journalInformation?journalCode=gnpl20

NATURAL PRODUCT RESEARCH
https://doi.org/10.1080/14786419.2021.1893318
Two new amide glycosides with anti-inflammatory
activity from the leaves of Streblus ilicifolius
(Vidal) Corner
Yan Huanga,b, Xishan Huanga, Guobiao Tiana, Wenxiu Zhanga, Shanshan Sua, Xia
Xua, Jun Lia and Buming Liub
aState Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, Collaborative
Innovation Center for Guangxi Ethnic Medicine, School of Chemistry and Pharmaceutical Science,
b
Guangxi Normal University, Guilin, China; Guangxi Key Laboratory of Tradtitional Chinese Medicine
Quality Standards, Guangxi Institute of Chinese Traditional Medical & Pharmaceutical Science,
Nanning, China
ABSTRACT
ARTICLE HISTORY
Received 21 December 2020
Accepted 17 February 2021
Two new amide glycosides, streblusoamides A (1) and B (2), along
with 11 known compounds (3–13) were isolated from the leaves
of Streblus ilicifolius. The structures of the isolates were elucidated
by spectroscopic methods. All of the isolates were tested for
inhibition of NO production in lipopolysaccharide (LPS)-induced
RAW 264.7 cells to investigate their anti-inflammatory effects. The
results revealed that compounds 1, 5 and 6 moderately inhibited
the release of NO production with IC50 values ranging from
50.90 lM to 64.79 lM.
KEYWORDS
Streblus ilicifolius (Vidal)
Corner; amide glycoside;
anti-inflammatory activity
1. Introduction
The genus Streblus is a small deciduous shrub belonging to the family of Moraceae. It
includes 20 species and mainly distributed in South China and South Asia. Previous
phytochemical investigations on the genus Streblus led to the isolation of phenylpro-
panoids (Li et al. 2012; Li et al. 2012, 2012, 2012, 2013;Li et al. 2014; He et al. 2016;
Nie et al. 2016; He et al. 2017), benzofurans (He et al. 2017), flavonoids (Li et al. 2012,
2012, 2012), steroids (Prakash et al. 1992; Shivendra et al. 2015; Ren et al. 2017; Miao
CONTACT Jun Li
lijun9593@163.com; Buming Liu
liu_buming@163.com
Supplemental data for this article can be accessed at https://doi.org/10.1080/14786419.2021.1893318.
ß 2021 Informa UK Limited, trading as Taylor & Francis Group

2
Y. HUANG ET AL.
et al. 2018) and terpenes (Li et al. 2012; Vidhu et al. 2012; Shivendra et al. 2015; Vidhu
et al. 2015; Verma et al. 2016). Extracts of the genus Streblus have been reported to
possess the effects of anti-inflammatory (Sripanidkulchai et al. 2009; Chen et al. 2011;
Huang et al. 2012), antibacterial (Taweechaisupapong et al. 2000; 2005; Li et al. 2012;
Huang et al. 2012; Neekhra et al. 2019), anti-hepatitis virus (Li et al. 2012, Li et al.
2012), anti-tumor (Alamgir et al. 2013; He et al. 2016), and anti-oxidation (Zhu et al.
2010; Prasansuklab et al. 2018; Neekhra et al. 2019).
In our previous researches, the investigations of plants of the genus Streblus
resulted in the isolation of a lot of phenylpropanoids and lignans (Li et al. 2012, 2012,
2012, 2013; Li 2014; He et al. 2016; Zhang et al. 2019). Streblus ilicifolius (Vidal) Corner,
a species of Streblus, distributes mainly in southern China (Zhang et al. 1998). It was
reported that the wood extract of S. ilicifolius showed the potential of antityrosinase
and antimicrobial activities (Sukanya et al. 2016). As part of an ongoing project to
assess the bioactive metabolites from the plants of the genus Streblus, we carried out
a phytochemical investigation on S. ilicifolius with anti-inflammatory activity. Two new
amide glycosides, streblusoamides A (1) and B (2), along with 11 known compounds,
were isolated from the leaves of the plant. Herein, the isolation, purification and deter-
mination of these isolates, the assay used to determine the anti-inflammatory activities
of the constituents are described.
2. Results and discussion
Phytochemical investigation of the 75% EtOH extract of the leaves of S. ilicifolius using
sequential column chromatography over silica gel, RP-C18 silica, Sephadex LH-20, along
with semipreparative HPLC to afford two new amide glycosides, streblusoamides A (1)
and B (2), together with 11 known compounds (3–13). The structures of the known
compounds were identified as adenine (3) (Chen et al. 2002), (-)-isolariciresinol 3A-O-
b-D-glucopyranoside (4) (Wang et al. 1998), moracin M 6-b-D-glucopyranoside (5)
(Piao et al. 2009), moracin M 30-(b-D-glucopyranoside) (6) (Cao et al. 2018), 5,50-dime-
thoxylariciresinol-40-O-b-D-glucoside (7) (Kiem et al. 2008), 5,50-dimethoxylariciresinol-4-
O-b-D-glucoside (8) (Yan et al. 2017), lariciresinol-4-O-b-D-glucopyranoside (9) (Li et al.
2005), kaempferol-7-O-b-D-glucoside (10) (Yang et al. 2013), benzyl-O-glucopyranoside
(11) (Ni et al. 2020), 4-(1,2,3-trihydroxypropyl)-2,6-dimethoxyphenyl-1-O-b-D-glucopyra-
noside (12) (Li et al. 2005) and prenyl glucoside (13) (Ly et al. 2002) (Figure 1).
Compound 1 was isolated as colorless, amorphous powder. In the UV spectrum, the
absorption maxima were exhibited at 285 and 318 nm. The IR spectrum displayed
characteristic absorption bands for amino (3362 cmꢀ1), acylamino (1657 cmꢀ1), phenyl
group (1599, 1546, 1514 cmꢀ1). It has a molecular formula of C19H27NO9 with 7
degrees of unsaturation based on the positive-ion HRESIMS peak at m/z 436.1582
(calcd for C19H27NO9Na, 436.1584) and NMR data (Supplementary material Table S1;
1
Figure S2). The H NMR spectrum of 1 showed signals attributed to a 1,3,4-substituted
phenyl moiety [dH 7.15 (d, J ¼ 2.0 Hz, H-2), 7.11 (dd, J ¼ 8.3, 2.0 Hz, H-6), 6.94 (d,
J ¼ 8.3 Hz, H-5)], a trans-vinyl [dH 7.45 (d, J ¼ 15.7 Hz, H-7), 6.51 (d, J ¼ 15.7 Hz, H-8)], an
oxygenated methylene [dH 3.95 (ddd, J ¼ 10.6, 6.6, 4.0, H-11a), 3.73 (ddd, J ¼ 10.6, 6.8,
4.0, H-11b)], a methylene [dH 3.55 (ddd, J ¼ 14.2, 6.6, 4.0, H-10a), 3.48 (ddd, J ¼ 14.2,

NATURAL PRODUCT RESEARCH
3
Figure 1. Structures of compounds 1–13.
6.8, 4.0, H-10b)], an anomeric sugar proton [dH 4.28 (d, J ¼ 7.8 Hz, H-10), and two
methoxy protons [dH 3.83 (s, 4-OCH3), 3.84 (s, 3-OCH3)] (Supplementary material Table
S1; Figure S3). The 13C NMR data, assigned with the aid of the HSQC spectrum, dis-
played 19 carbon resonances, including an amide carbonyl [dC 169.1 (C-9)], eight aro-
matic/olefinic carbons [dC 152.2 (C-4), 150.7 (C-3), 141.9 (C-7), 129.3 (C-1), 123.3 (C-6),
119.6 (C-8), 112.7 (C-5), 111.2 (C-2)], an oxygenated methylene carbon [dC 69.8 (C-11)],
a methylene carbon [dC 40.9 (C-10)], a glucopyranosyl moiety (dC 104.6, C-10; 75.1, C-20;
78.0, C-30; 71.6, C-40; 78.0, C-50; 62.7, C-60), and two oxygenated methyl carbons (dC
56.4 and 56.4) (Supplementary material Table S1; Figures S4-S5). These spectroscopic
data indicated that compound 1 has a trans-cinnamoyl moiety (Zhao et al. 2016), an
ethoxyl group and
a glucopyranosyl group. In the HMBC spectrum of 1
(Supplementary material Figures S1 and S6), the correlations of H-7 [dH 7.45 d (15.7)]
to C-2 (dC 111.2), C-6 (dC 123.3) and C-9 (dC 169.1), and H-8 [dH 6.51 d (15.7)] to C-1
(dC 129.4) and C-9 (dC 169.1) confirmed that C-1 was linked to C-7, which proved the
presence of a cinnamoyl moiety. Furthermore, the HMBC correlation of H-10 to C-9
revealed the linkage of the ethoxy moiety and trans-cinnamoyl moiety by an amide
bond. Moreover, The HMBC correlation from H-10 [dH 4.28 d (7.8)] to C-11 (dC 69.8)
showed that the sugar unit was attached to position C-11. In addition, glucose (Glc)
and its relative configuration were identified in the acid hydrolysis solution of 1 by
comparing with the authentic sample by performing TLC and HPLC test (see
0
Experimental Section). The coupling constant of J1’/2 ¼ 7.8 Hz of the anomeric proton
suggested that the sugar unit was b-oriented. The HMBC correlations of the methoxy
protons 4-OCH3 (dH 3.83) to C-4 (dC 152.2) and 3-OCH3 (dH 3.84) to C-3 (dC 150.7) sug-
gested that the two methoxy groups were located at C-3 and C-4, respectively.

4
Y. HUANG ET AL.
Therefore, compound 1 was established as (E)-(3,4-dimethoxy)-cinnamoyl-ethyl-O-b-D-
glucopyranoside and named streblusoamide A (Figure 1).
Compound 2 was obtained as colorless, amorphous powder. Its molecular formula
C17H23NO7 was determined by the positive-ion HRESIMS peak at m/z, 376.1369
[M þ Na]þ (calcd for C17H23NO7Na, 376.1372) (Supplementary material Figure S7), which
is 60 Da less than that of 1, suggesting that 2 possesses two less methoxy groups than
1. In the UV spectrum, the absorption maxima was exhibited at 270 nm. The IR spectrum
of 2 displayed prominent absorption maxima at 3353, 1658, 1616, 1578, 1546 and
1066 cmꢀ1, indicating the presence of amino, acylamino and phenyl functionalities.
Compound 2 had identical NMR (Supplementary material Table S1; Figures S8-S9) data
to those of 1, as revealed by comparison of their MS and NMR signals, indicating that 2
1
was an analogue of 1. The differences existed in the H and 13C NMR data of the phenyl
groups and methoxy groups between 2 and 1 (Supplementary material Table S1; Figures
1
S8-S9). The H NMR signals of 2 showed five phenyl proton peaks at dH 7.37 (m, H-2, 6),
7.56 (m, H-3, 5) and 7.36 (m, H-4), suggesting the presence of an one-substituted phenyl
moiety in 2 (Supplementary material Table S1; Figure S8). Moreover, the 13C NMR signals
of phenyl carbons were changed from dC 129.3 (C-1), 152.2 (C-2), 112.7 (C-3), 123.3 (C-4),
150.7 (C-5), 111.2 (C-6) in 1 to dC 136.3 (C-1), 130.0 (C-2, 6), 128.8 (C-3, 5), 130.8 (C-4) in
1
2, respectively (Supplementary material Table S1). Comparison of their H and 13C NMR
data (Supplementary material Table S1) showed that two hydrogen atoms [dH 7.56 (1H,
m), dC 128.8] and [dH 7.36 (1H, m), dC 130.8] were situated at C-3 and C-4 in 2 instead of
two methoxy groups at C-3 and C-4 in 1. In the HMBC spectrum of 2 (Supplementary
material Figures S1 and S11), the correlations of H-7 [dH 7.54 d (15.8)] to C-1 (dC 131.3),
C-2/6 (dC 130.0), C-8 (dC 121.8) and C-9 (dC 168.1), and H-8 [dH 6.65 d (15.8)] to C-1 (dC
136.3) and C-9 (dC 168.1) suggested that C-1 was linked to C-7, which proved the pres-
ence of a cinnamoyl moiety. In addition, the sugar moiety was determined as a D-glu-
1
cose based on the H-NMR and 13C-NMR data (Supplementary material Table S1), acid
hydrolysis and TLC and HPLC test with an authentic sample (see Experimental Section).
0
The coupling constant of J1’/2 ¼ 7.7 Hz of the anomeric proton revealed that the gluco-
side unit was b-oriented. Therefore, compound 2 was determined to be (E)-cinnamoyl-
ethyl-O-b-D-glucopyranoside and named streblusoside B (Figure 1).
All the isolates were subjected to an anti-inflammatory assay in vitro against RAW
264.7 cells (Supplementary material Table S2). Cell viability was measured by a MTT
assay. At the effective concentration, all the compounds showed no obvious cytotox-
icity to the RAW264.7 cells. The results showed that compounds 1, 5 and 6 had mod-
erate inhibitory activities with IC50 values ranging from 50.90 lM to 64.79 lM, and 1, 5
and 6 were weaker than the positive control, dexamethasone, with an IC50 value of
44.99 lM. The other compounds showed no effects to the release of NO production.
3. Experimental
3.1. General
The optical rotations were obtained using an ADP440þ polarimeter. HRESIMS were
carried out on a Waters/Micromass Q-TOF-Ultima (Waters, Milford, MA, USA) mass
spectrometer. NMR spectra were performed on
a Bruker Advance 400 MHz

NATURAL PRODUCT RESEARCH
5
spectrometer and 600 MHz spectrometer. Semi-preparative HPLC was performed using
a Waters 2695 HPLC system, and samples were separated on a Waters SunFire-C18 col-
umn (5 lm, i.d. 10 mm ꢁ 250 mm). Analytical HPLC was conducted on a Waters 2695
instrument (Waters Corporation, Milford, Massachusetts MA, USA) using Waters 2424
ELSD as detector and D-glucose was analyzed as sugar standard (Sigma) by HPLC on a
GH0525046C18AQ column (5 lm, 4.6 ꢁ 250 mm, Sil Green). Optical rotations were
measured on an ADP440þ polarimeter (k 589 nm, path length 1.0 cm).
3.2. Plant material
The leave of S. ilicifolius was collected in August 2018 from Lingshui, a city of Hainan
province, China, and was authenticated by Prof. Guodong Li, College of Traditional
Chinese Medicine, Yunnan University of Chinese Medicine. A voucher specimen has
been deposited in the Natural Products Laboratory of Guangxi Normal University,
registration No. ZFC201906025e.
3.3. Extraction and isolation
The air-dried leaves (10 kg) of S. ilicifolius were refluxed with 75% EtOH (2 h ꢁ 3) to
generate a crude extract (0.75 kg). The crude extract was suspended in water and suc-
cessively partitioned with different solvents into EtOAc (Fraction A, 143 g) and n-BuOH
(Fraction B, 500 g) fractions. The n-BuOH extract was applied to a silica gel CC, eluting
with a CH2Cl2-MeOH (100:0-0:100, v/v) to give five fractions (Fr.B.1-Fr.B.5). Fr. B.2
(16.7 g) was subjected to a RP-18 column using a step gradient of H2O-MeOH (95:5 !
0:100, v/v) to afford eight fractions (Fr.B.2.1-Fr.B.2.8). Fr.B.2.1 (4.0 g) was chromato-
graphed over Sephadex LH-20 column, eluting with CH2Cl2-MeOH (1:1) to give five
fractions (Fr.B.2.1.1-Fr.B.2.1.5). Fr.B.2.1.4 (111 mg) was purified by semi-preparative
HPLC (H2O-MeOH, 93:7, v/v) to yield compound 3 (4.0 mg). Compounds 11 (5.1 mg)
and 13 (1.1 mg) were achieved from Fr.B.2.1.2 by Sephadex LH-20 column and then
purified by semi-preparative HPLC (H2O-MeOH, 85:15, v/v). Fr.B.3 (93 g) was loaded
onto a RP-C18 column with a gradient of H2O-MeOH (95:5 ! 0:100, v/v) to afford eight
subfractions Fr.B.3.1-Fr.B.3.8. Fr.B.3.3 (7.97 g) was separated by the Sephadex LH-20 col-
umn eluted with CH2Cl2-MeOH (1:1) and the semi-preparative HPLC (H2O-MeOH, 85:15,
v/v) to afford compounds 4 (13.2 mg), 5 (7.2 mg), 6 (10.3 mg), 7 (6.7 mg), 8 (4.0 mg), 9
(4.2 mg), 10 (4.2 mg), and 12 (2.8 mg), respectively. Compounds 1 (2.1 mg) and 2
(38.1 mg) were obtained from Fr.B.3.4 by MCI column chromatography with a gradient
of H2O-MeOH (95:5 ! 0:100, v/v), silica gel column chromatography using a step gra-
dient of CH2Cl2-MeOH (100:0-0:100, v/v) and the semi-preparative HPLC (H2O-MeOH,
85:15, v/v), respectively.
3.3.1. (E)-(3,4-dimethoxy)-cinnamoyl-ethyl-O-b-D-glucopyranoside (streblusoside
A) (1)
Colorless amorphous powder, [A] ꢀ 7.59 (c 0.12, MeOH); UV (MeOH): kmax (nm) ¼ 285
and 318; IR (KBr): ꢀmax ¼ 3362, 1657, 1599, 1546, 1514, 1463, 1382, 1262, 1024 cmꢀ1
.
1
HRESIMS m/z 436.1582 [M þ Na]þ, calcd for C19H27NO9Na, 436.1584; H NMR (600 MHz,

6
Y. HUANG ET AL.
CD3OD) d 7.45 (d, J ¼ 15.7 Hz, H-7), 7.15 (d, J ¼ 2.0 Hz, H-2), 7.11 (dd, J ¼ 8.3, 2.0 Hz, H-
6), 6.94 (d, J ¼ 8.3 Hz, H-5), 6.51 (d, J ¼ 15.7 Hz, H-8), 4.28 (d, J ¼ 7.8 Hz, H-10), 3.95 (ddd,
J ¼ 10.6, 6.7, 3.9 Hz, H-11a), 3.84 (s, 3-OCH3), 3.83 (s, 4-OCH3), 3.85 (m, H-6’a), 3.73 (ddd,
J ¼ 10.6, 6.7, 3.7 Hz, H-11b), 3.65 (m, H-6’b), 3.55 (m, H-10a), 3.48 (m, H-10b), 3.35 (m,
H-50), 3.28 (m, H-40), 3.25 (m, H-30), 3.19 (m, H-20); 13C NMR (150 MHz, CD3OD) d 169.1
(C-9), 152.2 (C-4), 150.7 (C-3), 141.9 (C-7), 129.3 (C-1), 123.3 (C-6), 119.6 (C-8), 112.7 (C-
5), 111.2 (C-2), 104.6 (C-10), 78.0 (C-30), 78.0 (C-50), 75.1 (C-20), 71.6 (C-40), 69.8 (C-11),
62.7 (C-60), 56.4 (3-OCH3), 56.4 (4-OCH3), 40.9 (C-10).
3.3.2. (E)-cinnamoyl-ethyl-O-b-D-glucopyranoside (streblusoside B) (2)
Colorless amorphous powder, [A] ꢀ 32.88 (c 0.04, MeOH); UV (MeOH): kmax (nm) ¼
270; IR (KBr): ꢀmax ¼ 3353, 1658, 1616, 1578, 1546, 1450, 1341, 1286, 1037 cmꢀ1
.
HRESIMS m/z 376.1369 [M þ Na]þ, calcd for C17H23NO7Na, 376.1372; 1H NMR
(400 MHz, CD3OD) d 7.56 (m, H-3,5), 7.56 (m, H-7), 7.37 (m, H-2, 6), 7.36 (m, H-4),
6.65 (d, J ¼ 15.8 Hz, H-8), 4.30 (d, J ¼ 7.7 Hz, H-10), 3.97 (ddd, J ¼ 10.5, 6.4, 4.0 Hz, H-
11a), 3.88 (dd, J ¼ 11.9, 1.6 Hz, H-6’a), 3.74 (ddd, J ¼ 10.7, 6.8, 3.9 Hz, H-11b), 3.67
(m, H-6’b), 3.58 (ddd, J ¼ 14.2, 6.4, 3.9 Hz, H-10a), 3.50 (ddd, J ¼ 14.2, 6.8, 4.0 Hz, H-
10b), 3.34 (m, H-50), 3.30 (m, H-40), 3.28 (m, H-30), 3.21 (m, H-20); 13C NMR
(100 MHz, CD3OD) d 168.7 (C-9), 141.9 (C-7), 136.3 (C-1), 130.8 (C-4), 130.0 (C-2, 6),
128.8 (C-3,5), 121.8 (C-8), 104.6 (C-10), 78.0 (C-30), 78.0 (C-50), 75.1 (C-20), 71.6 (C-40),
69.8 (C-11), 62.7 (C-60), 40.9 (C-10).
3.4. Hydrolyses of compounds 1 and 2
Acidic hydrolyses of compounds 1 and 2 were carried out according to the
method described previously (He et al. 2017). The sugar moieties were determined
by comparing the Rf values of the products by TLC on silica gel with authentic
samples as reference and EtOAc-pyridine-EtOH-H2O (8:1:1:2) as mobile phase. The Rf
values were 0.39 (D-glucose). The sugar moiety from 1 and 2 was identified as D-
glucose based on the comparison of the retention time of an authentic sample (tR:
D-glucose 15.32 min) by HPLC on a GH0525046C18AQ column (5 lm, 4.6 ꢁ 250 mm,
Sil Green) using formic acid: water ¼ 0.5: 100 (v/v) as mobile phase (Figure S16
and S17).
3.5. Anti-inflammatory assay
The anti-inflammatory effects of compounds (1-13) were examined on the production
of nitric oxide (NO) in LPS-stimulated cells using a method according to our previously
described method (Zhang et al. 2018). The macrophage cell line was RAW 264.7, Cells
(5 ꢁ 105 cells/mL) were grown in DMEM and cultured in 96-well plates at 37 ꢂC. Cells
were pretreated with or without test compounds for 2 h, then incubated with LPS for
24 h. NO production was determined by measuring the nitrite concentration using the
Griess reagent. Results are expressed as the means SD, n ¼ 3.

NATURAL PRODUCT RESEARCH
7
4. Conclusion
Two new amide glycosides, streblusoamides A (1) and B (2), together with 11 known
compounds, were isolated from S. ilicifolius. Their structures were determined by
extensive spectroscopic analyses and comparison with literature data. The results
revealed that compounds 1, 5 and 6 showed moderate inhibitory activities.
Supporting material
All spectral data associated with this research article are provided as supplemen-
tary file.
Disclosure statement
No potential conflict of interest was reported by the authors.
Funding
This research work was financially supported by National Natural Science Foundation
(21662004), the Province Natural Science Foundation (2018GXNSFDA050007 and
2018GXNSFAA050042), Guangxi Key Laboratory of Traditional Chinese Medicine Quality
Standards (grant number GZZK202001) and the Key Laboratory for the Chemistry and Molecular
Engineering of Medicinal Resources (CMEMR2019-A1).
References
Alamgir A, Rahman M, Rahman A. 2013. Phytochemical characteristics, antimitotic, cytotoxic and
antitumor activities of bark extract of Streblus asper Lour. Bangladesh J Bot. 42 (1):17–22.
Cao YG, Zheng XK, Yang FF, Li F, Qi M, Zhang YL, Zhao X, Kuang HX, Feng WS. 2018. Two new
phenolic constituents from the root bark of Morus alba L. and their cardioprotective activity.
Nat Prod Res. 32(4):391–398.
Chen ZZ, Li J, Wu Q, Yang RY, Li LQ, Li S, Huang JG. 2011. Chemical constituents and antiphlo-
gistic activity of the bark of Streblus asper. Guihaia. 31(6):849–852.
Chen Q, Wu LJ, Ruan LJ. 2002. Chemical studies on the constituents of Lophatherum gracile
Brongn. J Shenyang Pharm Univ. 19(4):257–259.
Li C, Huang CP, LuTL, Wu LD, Deng SP, Yang RY, Li J. 2014. Tandem mass spectrometric frag-
mentation behavior of lignans, flavonoids and triterpenoids in Streblus asper. Rapid Commun
Mass Spectrom. 28(21):2363–2370.
He RJ, Deng SP, Nie H, Huang Y, Liu BM, Yang RY, Huang S, Zhou DX, Chen HC, Li J, et al. 2017.
Two new coumarins from the bark of Streblus indicus (Bur.) Corner. Nat Prod Res. 31(9):
1052–1058.
He RJ, Huang XS, Zhang YJ, Wu LD, Nie H, Zhou DX, Liu BM, Deng SP, Yang RY, Huang S, et al.
2016. Structural characterization and assessment of the cytotoxicity of 2,3-dihydro-1H-indene
derivatives and coumarin glucosides from the bark of Streblus indicus. J Nat Prod. 79(10):
2472–2478.
He RJ, Zhang YJ, Wu LD, Nie H, Huang Y, Liu BM, Deng SP, Yang RY, Huang S, Nong ZJ, et al.
2017. Benzofuran glycosides and coumarins from the bark of Streblus indicus (Bur.) Corner.
Phytochemistry. 138:170–177.
Huang JG, Li J, Wu Q, Yang R, LS, Chen ZZ, Li LQ. 2012. Constituents from heartwood of Streblus
asper and their antibacterial activity. Nat Prod Res Dev. 24(6):780–783.

8
Y. HUANG ET AL.
Kiem PV, Tri MD, Tuong LV, Tung NH, Hanh NN, Quang TH, Cuong NX, Minh CV, Choi EM, Kim
YH. 2008. Chemical constituents from the leaves of Manglietia phuthoensis and their effects
on osteoblastic MC3T3-E1 cells. Chem Pharm Bull. 56(9):1270–1275.
Li B, Chen WS, Zhao Y, Zhang HM, Dong JX, Qiao CZ. 2005. Phenylpropanoids isolated from
tetraploid roots of Isatis indigotica. Chin Tradit Herb Drugs. 36(3):326–328.
Li J, Huang Y, Guan XL, Li J, Deng SP, Wu Q, Zhang YJ, Su XJ, Yang RY. 2012. Anti-hepatitis B
virus constituents from the stem bark of Streblus asper. Phytochemistry. 82:100–109.
Li LQ, Li J, Huang Y, Wu Q, Deng SP, Su XJ, Yang RY, Huang JG, Chen ZZ, Li S. 2012. Lignans
from the heartwood of Streblus asper and their inhibiting activities to hepatitis B virus.
Fitoterapia. 83(2):303–309.
Li J, Meng AP, Guan XL, Li J, Wu Q, Deng SP, Su XJ, Yang RY. 2013. Anti-hepatitis B virus lignans
from the root of Streblus asper. Bioorg Med Chem Lett. 23(7):2238–2244.
Li J, Tang MT, Wu Q, Chen H, Niu XT, Guan XL, Li J, Deng SP, Su XJ, Yang RY. 2012. Water-sol-
uble constituents of the heartwood of Streblus asper. Nat Prod Commun. 7(5):599–602.
Li TZ, Zhang WD, Gu ZB, Liu WY, Zhang C, Liu RH. 2005. Lignans from Patrinia scabra. Chin
Tradit Herb Drugs. 36(3):338–340.
Ly TN, Yamauchi R, Shimoyamada M, Kato K. 2002. Isolation and structural elucidation of some
glycosides from the rhizomes of smaller galanga (Alpinia officinarum Hance). J Agric Food
Chem. 50(17):4919–4924.
Miao D, Zhang TQ, Xu J, Ma CY, Liu WY, Kikuchi T, Akihisa T, Abe M, Feng F, Zhang J. 2018.
Three new cardiac glycosides obtained from the roots of Streblus asper Lour. and their cyto-
toxic and melanogenesis-inhibitory activities. RSC Adv. 8(35):19570–19579.
Neekhra S, Awasthi H, Singh D. 2019. Effect of Streblus asper leaves on locomotion, anxiety and
cognition in rats. Asian J Pharm Clin Res. 12(2):98–101.
Ni L, Huang W, Shi Y, Wang H, Qiu Y, Xu H. 2020. Chemical constituents from the bark of bauhi-
nia purpurea and their NO inhibitory activities. Nat Prod Res. 34(17):2424–2429.
Nie H, Guan XL, Li J, Zhang YJ, He RJ, Huang Y, Liu BM, Zhou DX, Deng SP, Chen HC, et al.
2016. Antimicrobial lignans derived from the roots of Streblus asper. Phytochem Lett. 18:
226–231.
Piao SJ, Qiu F, Chen LX, Pan Y, Dou DQ. 2009. New stilbene, benzofuran, and coumarin glyco-
sides from Morus alba. HCA. 92(3):579–587.
Prakash K, Deepak D, Khare A, Khare MP. 1992. A pregnane glycoside from Streblus asper.
Phytochemistry. 31(3):1056–1057.
Prasansuklab A, Theerasri A, Payne M, Ung AT, Tencomnao T. 2018. Acid-base fractions sepa-
rated from Streblus asper leaf ethanolic extract exhibited antibacterial, antioxidant, anti-acetyl-
cholinesterase, and neuroprotective activities. BMC Complement Altern Med. 18(1):223–235.
Ren YL, Chen WL, Lantvit DD, Sass EJ, Shriwas P, Ninh TN, Chai HB, Zhang XL, Soejarto DD,
Chen XZ, et al. 2017. Cardiac glycoside constituents of Streblus asper with potential antineo-
plastic activity. J Nat Prod. 80(3):648–658.
Shivendra PS, Abhay PS, Reena S, Praveen KR, Ashok KT, Navneet KV. 2015. A brief study on
Strebulus asper L. -A Review. Res J Phytomed. 1:65–71.
Sripanidkulchai B, Junlatat J, Wara-Aswapati N, Hormdee D. 2009. Anti-inflammatory effect of
Streblus asper leaf extract in rats and its modulation on inflammation-associated genes
expression in RAW 264.7 macrophage cells. J Ethnopharmacol. 124(3):566–570.
Sukanya D, Kedsaraporn P, Chatchai W. 2016. Determination of phytochemical compounds, and
tyrosinase inhibitory and antimicrobial activities of bioactive compounds from Streblus ilicifo-
lius (S Vidal) Corner. Trop J Pharm Res. 15(3):497–506.
Taweechaisupapong S, Choopan T, Singhara S, Chatrchaiwiwatana S, Wongkham S. 2005. In vitro
inhibitory effect of Streblus asper leaf-extract on adhesion of Candida albicans to human buc-
cal epithelial cells. J Ethnopharmacol. 96(1–2):221–226.
Taweechaisupapong S, Wongkham S, Chareonsuk S, Suparee S, Srilalai P, Chaiyarak S. 2000.
Selective activity of Streblus asper on Mutans streptococci. J Ethnopharmacol. 70(1):73–79.

NATURAL PRODUCT RESEARCH
9
Verma V, Tripathi AC, Saraf SK. 2016. Bioactive non-sterol triterpenoid from Streblus asper: micro-
wave-assisted extraction, HPTLC profiling, computational studies and neuro-pharmacological
evaluation in BALB/c mice. Pharm Biol. 54(11):2454–2464.
Vidhu A, Perwez A, Mohammed A, Ilyas UK. 2012. Isolation of new aliphatic ester linked with
d-lactone cos-11-enyl pentan-1-oic-1,5-olide from the roots of Streblus asper Lour. Indo Global
J Pharm Sci. 2(2):114–120.
Vidhu A, Perwez A, Mohammed A, Kamran JN. 2015. Lupene-type triterpenic and steroidal con-
stituents from the roots of Streblus asper Lour. J Sci and Innovative Res. 4(3):142–145.
Wang MF, Li JG, Rangarajan M, Shao Y, LaVoie EJ, Huang TC, Ho CT. 1998. Antioxidative phenolic
compounds from sage (Salvia officinalis). J Agric Food Chem. 46(12):4869–4873.
Yan XJ, Zheng W, , Wen J, , Wu J, , Bai M, Xiang Z. 2017. Lignan constituents of Patrinia villosa
(Thunb.) Juss. Chin Pharm J. 52(13):1126–1131.
Yang BY, Li T, Guo R, Wang QH, Kuang HX. 2013. Chemical constituents from leaves of Datura
metel (I). Chin Tradit Herb Drugs. 44(20):2803–2807.
Zhang GR, Hao LL, Zhou DX, Liu W, Li CG, Su SS, Xu X, Huang XS, Li J. 2019. A new phenylpro-
panoid glycoside from the bark of Streblus ilicifolius (Vidal) Corner. Biochem System and
Ecolo. 87:103962.
Zhang YJ, Wang K, Chen HC, He RJ, Cai RL, Li J, Zhou DX, Liu W, Huang XS, Yang RY, Deng SP,
et al. 2018. Anti-inflammatory lignans and phenylethanoid glycosides from the root of Isodon
^
ternifolius (D.Don) Kudo. Phytochemistry. 153(9):36–47.
Zhao ND, Yang GY, Zhang Y, Chen LJ, Chen YG. 2016. A new 9,10-dihydrophenanthrene from
Dendrobium moniliforme. Nat Prod Res. 30(2):174–179.
Zhu SJ, Li J, Meng AP, Liu QY, Huang CP. 2010. Antioxidant activity of extracts from leaves of
Streblus asper. J Guangxi Normal Univ (Natural Science). 28(3):33–36.