Four flavone glycosides were isolated from the leaves of Antidesma ghaesembilla. They were elucidated to be vitexin, orientin, isovitexin, and homoorientin by 1D- and 2D-NMR and in comparison with literature data. These compounds have been reported from the genus Antidesma for the first time

Cuc, Nguyen Thi

Huong, Le Mai

Kiem, Phan Van

Minh, Chau Van

Nhiem, Nguyen Xuan

Trang, Do Thi

Tuan Anh, Hoang Le

Viet Cuong, Le Canh

Yen, Pham Hai

Vietnam Academy of Science and Technology: Journals Online

  
94 
VIETNAM JOURNAL OF CHEMISTRY         VOL. 53(2e) 94-97                                               APRIL 2015 
DOI: 10.15625/0866-7144.2015-2e-022 
  
 
 
FLAVONOID GLYCOSIDES FROM Antidesma ghaesembilla 
 
Le Canh Viet Cuong
1
, Do Thi Trang
1
, Nguyen Thi Cuc
1
, Nguyen Xuan Nhiem
1
, Pham Hai Yen
1
,  
Hoang Le Tuan Anh
1
, Le Mai Huong
2
, Chau Van Minh
1
, Phan Van Kiem
1* 
1
Institute of Marine Biochemistry, Vietnam Academy of Science and Technology (VAST) 
2
Institute of Natural Products Chemistry, VAST 
Received 23 January 2015; Accepted for Publication 18 March 2015 
 
Abstract 
Four flavone glycosides were isolated from the leaves of Antidesma ghaesembilla. They were elucidated to be 
vitexin, orientin, isovitexin, and homoorientin by 1D- and 2D-NMR and in comparison with literature data. These 
compounds have been reported from the genus Antidesma for the first time. 
Keywords. Antidesma ghaesembilla, vitexin, orientin, isovitexin, homoorientin. 
  
1. INTRODUCTION 
 
 Antidesma is a genus of tropical plants 
belonging to Euphorbiaceae family, comprise about 
100 species in the world and 29 species in Vietnam. 
The leaves of A. ghaesembilla have been used in 
traditional medicine for treatment of skill diseases 
and headache [1]. In addition, its fruits have been 
used to treat sore throat and lung disease [1]. 
However, there are few reports about chemical 
constituents and biological activities of this plant [2, 
3]. As part of our ongoing chemical investigations 
on the genus Antidesma, we report herein the 
isolation and structural elucidation of C-glucose 
flavones from the leaves of A. ghaesembilla. 
 
2. MATERIAL AND METHODS 
 
2.1. Plant Material 
 
 The leaves of Antidesma ghaesembilla Gaertner 
were collected in Dak Lak province, Vietnam, in 
March 2013, and identified by Dr. Nguyen Quoc 
Binh, Vietnam National Museum of Nature. A 
voucher specimen was deposited at Institute of 
Marine Biochemistry, VAST.  
 
2.2. General experimental procedures 
 
All NMR spectra were recorded on a Bruker 
AM500 FT-NMR spectrometer (500 MHz for 
1
H-
NMR and 125 MHz for 
13
C-NMR). NMR 
measurements, including 
1
H-NMR, 
13
C-NMR, 
HSQC, and HMBC experiments, were carried out 
using 5-mm probe tubes at temperature of 22.2 
o
C. 
Melting points were recorded in Kofler micro-
hostage. Optical rotations were determined on a 
Jasco DIP-1000 polarimeter. Column 
chromatography was performed using a silica-gel 
(Kieselgel 60,70-230 mesh and 230-400 mesh, 
Merck) or RP-18 resins (30-50 µm, Fujisilisa 
Chemical Ltd.), thin layer chromatography (TLC) 
using a pre-coated silica-gel 60 F254 (0.25 mm, 
Merck) and RP-18 F254S plates (0.25 mm, Merck). 
 
2.3. Extraction and isolation 
 
The dried leaves of A. ghaesembilla (2.5 kg) 
were sonicated in MeOH three times to yield 115.0 g 
of a dark solid extract, which was then suspended in 
water and successively partitioned with 
dichloromethane and ethyl acetate (EtOAc) to obtain 
dichloromethane (AG1, 30.0 g), ethyl acetate (AG2, 
20.0 g), and water layers (AG3, 65.0 g) after 
removal solvent in vacuo. The EtOAc layer (AG2, 
20.0 g) was chromatographed on a silica gel column 
eluting with CH2Cl2/MeOH/water (5/1/0.1, v/v/v) to 
give three fractions, AG2A-AG2C. The AG2B 
fraction was chromatographed on a RP-18 column 
eluting with MeOH/water (1/1.5, v/v) to yield 
compounds 1 (15.0 mg) and 2 (7.0 mg). The water 
layer (AG3, 65.0 g) was chromatographed on a 
Diaion HP-20 column eluting with water to remove 
sugar, then increase concentration of methanol in 
water (25, 50, 75, and 100 %) to obtain four 
fractions, AG3A-AG3D. The AG3D fraction was 
 95 
VJC, Vol. 53(2e), 2015                                                                                                      Phan Van Kiem, et al. 
chromatographed on a silica gel column eluting with 
CH2Cl2/MeOH/water (5/1/0.1, v/v/v) to give three 
fractions, AG3D1-AG3D3. The AG3D2 fraction 
was chromatographed on a RP-18 column eluting 
with MeOH/water (1/1.5, v/v) to yield compounds 3 
(10.0 mg) and 4 (8.0 mg). 
Vitexin (1): Yellow amorphous powder, 
C21H20O10; 25][ D : -14.0 (c = 0.1, MeOH), mp: 263 
o
C,  
1
H- and 
13
C-NMR (DMSO-d6), see table 1. 
Orientin (2): Yellow amorphous powder, 
C21H20O11, 25][ D : -25.0 (c = 0.1, MeOH), mp: 264 
o
C, 
1
H- and 
13
C-NMR (DMSO-d6), see table 1. 
Isovitexin (3): Yellow amorphous powder, 
C21H20O10, 25][ D : +16.2 (c = 0.4, MeOH), mp: 234 
o
C, 
1
H- and 
13
C-NMR (CD3OD), see table 1. 
Homoorientin (4): Yellow amorphous powder, 
C21H20O11, 25][ D : +22.0 (c = 0.1, MeOH), mp: 236 
o
C, 
1
H- and 
13
C-NMR (DMSO-d6), see table 1. 
 
Figure 1: Chemical structures of 1-4 
 
3. RESULTS AND DISCUSSION 
 
Compound 1 was obtained as a yellow 
amorphous powder. The 
1
H-NMR of compound 1 (in 
DMSO-d6) showed the following signals: four 
aromatic protons of the AA′BB′ coupling system in B 
ring at δH 6.89 (2H, d, J = 8.0 Hz) and 8.02 (2H, d, J 
= 8.0 Hz); two singlet protons at δH 6.27 (1H, s) and 
6.77 (1H, s) assigned to a flavone aglycone; one 
anomeric proton at δH 4.69 (1H, d, J = 10.0 Hz), 
assigned to a C-sugar unit. The 
13
C-NMR and DEPT 
spectra revealed the signals of 21 carbons, including 
one carbonyl at δC 182.04, eight non-protonated 
carbons at δC 104.59, 104.59, 121.59, 155.98, 160.38, 
161.12, 162.68, and 163.91, eleven methine carbons 
at δC 70.54, 70.84, 73.36, 78.65, 81.80, 98.14, 102.41, 
115.80 × 2, 128.92 × 2,  and one methylene carbon at 
δC 61.28. The 
1
H- and 
13
C-NMR data of 1 were 
similar those of vitexin [4]. The HMBC cross peaks 
from H-3 (δH 6.77) to C-1' (δC 121.59)/C-2 (δC 
163.91)/C-4 (δC 182.04)/C-10 (δC 105.7); from H-6 
(δH 6.27) to C-5 (δC 160.38)/C-7 (δC 162.68)/C-8 (δC 
104.59)/C-10 (δC 104.00) confirmed that two singlet 
protons were at C-3 and C-6. The large coupling 
constant JH-1′/H-2′ = 10.0 Hz and 
13
C-NMR chemical 
shifts of sugar moiety (δC 73.36, 70.84, 78.65, 70.54, 
81.80, and 61.28) were very typical of C-
glucopyranosyl moiety. In addition, this sugar was 
attached to C-8 confirming by the HMBC correlation 
between glc H-1′ (δH 4.69) and C-8 (δC 104.59). The 
HMBC correlations between H-2′ (δH 8.02)/H-3′ (δH 
6.89) and C-4′ (δC 161.12) suggested that the 
hydroxyl group was at C-4′ of flavone. Consequently, 
the structure of 1 was determined to be vitexin.   
The 
1
H-NMR of 2 (DMSO-d6) showed revealed 
the signals of three aromatic protons of ABX 
aromatic system in B ring at δH 6.86 (1H, d, J = 8.0 
Hz), 7.48 (1H, br s), and 7.53 (br d, J = 8.0 Hz); two 
singlet protons at δH 6.26 (1H, s) and 6.63 (1H, s), 
assigned to a flavone aglycone; one anomeric proton 
at δH 4.69 (1H, d, J = 10.0 Hz), assigned to a C-sugar 
unit. The 
1
H- and 
13
C-NMR of 2 were almost similar 
to those of 1 except for an addition of hydroxyl group 
at C-3′ in B ring as orientin. In addition, its NMR data 
were identical to those of orientin and found to match 
[4].  
The 
1
H-, 
13
C-NMR and DEPT spectra of 3 
revealed the signals of the flavone glycoside, 
including one carbonyl, eight non-protonateds, eleven 
methines, and one methylene. The 
1
H- and 
13
C-NMR 
data of 3 were found to be similar those of vitexin 
except for the position of C-sugar at C-6. The sugar 
was proved to be C-glucose by comparing its NMR 
data to those of vitexin (1). The position of this sugar 
at C-6 was confirmed by the HMBC correlation 
between glc H-1′ (δH 4.87) and C-6 (δC 109.51). The 
positions of the remaining functional groups were 
based on the HSQC and HMBC spectra. Thus, the 
structure of 3 was determined to be isovitexin [5]. 
 96 
VJC, Vol. 53(2e), 2015                                                      Flavonoid glycosides from Antidesma ghaesembilla. 
Table 1: The 
1
H- and 
13
C-NMR data for compounds 1-4 and reference compounds 
Pos
. 
 
1
   
2
   
3
  
 4  
δC* δC
a
 
δH
a 
(mult., 
J, Hz) 
δC
$ δC
a δH
a 
(mult., 
J, Hz) 
δC
# δC
b δH
b 
(mult., J, 
Hz) 
δC
@
 δC
a
 
δH
a 
(mult., J, 
Hz) 
Aglycone           
2 165.0 163.91 - 164.2 164.05 - 164.3 165.95 - 163.6 163.28 - 
3 102.5 102.41 6.77 (s) 102.4 102.34 6.63 (s) 103.9 103.60 6.52 (s) 102.6 102.80 6.67 (s) 
4 182.7 182.04 - 182.0 181.95 - 182.9 183.78 - 181.7 181.86 - 
5 160.3 160.38 - 160.5 160.35 - 157.5  - 160.6 160.68 - 
6 98.5 98.14 6.27 (s) 98.3 98.11 6.26 (s) 110.1 109.51 - 108.9 108.87 - 
7 162.3 162.68 - 162.8 162.69 - 165.0 163.02 - 163.1 163.66 - 
8 104.6 104.59 - 104.6 104.52 - 94.7 95.71 6.42 (s) 93.2 93.52 6.48 (s) 
9 155.6 155.98 - 156.0 155.97 - 162.1 158.82 - 156.1 156.21 - 
10 104.1 104.00 - 104.0 103.94 - 104.8 104.55 - 103.4 103.40 - 
1′ 122.1 121.59 - 122.0 121.93 - 122.2 123.02 - 121.4 121.43 - 
2′ 129.0 128.92 8.02 (d, 
8.0) 
114.1 113.99 7.48 (br s) 128.9 129.37 7.79 (d, 8.0) 113.1 113.30 7.40 (d, 2.0) 
3′ 115.0 115.80 6.89 (d, 
8.0) 
146.0 145.79 - 116.8 117.10 6.88 (d, 8.0) 145.8 145.75 - 
4′ 161.3 161.12 - 149.9 149.66 - 162.7 162.02 - 149.7 149.72 - 
5′ 115.0 115.80 6.89 (d, 
8.0) 
115.8 115.62 6.86 (d, 
8.0) 
116.8 117.10 6.88 (d, 8.0) 115.7 116.06 6.89 (d, 8.0) 
6' 129.0 128.92 8.02 (d, 
8.0) 
119.4 119.33 7.53 (br d, 
8.0) 
128.9 129.37 7.79 (d, 8.0) 118.7 118.97 7.42 (dd, 2.0, 
8.0) 
6 or 8-C-Glc          
1″ 73.9 73.36 4.69 (d, 
10.0) 
73.5 73.37 4.69 (d, 
10.0) 
75.6 75.35 4.87 (d, 10.0) 72.8 73.06 4.59 (d, 10.0) 
2″ 71.0 70.84 3.84 (dd, 
9.0,10.0) 
70.9 70.76 3.84 (dd, 
9.0,10.0) 
72.9 72.47 4.19 (dd, 9.0, 
10.0) 
69.9 70.62 4.04 (dd, 
9.0,10.0) 
3″ 79.0 78.65 3.29 78.9 78.74 3.30 80.6 80.25 3.46 78.7 78.95 3.16 
4″ 70.2 70.54 3.34 70.8 70.68 3.37 71.9 71.73 3.46 70.4 70.22 3.22 
5″ 81.3 81.80 3.26 82.0 81.95 3.27 83.0 82.56 3.90 81.4 81.55 3.14 
6″ 61.4 61.28 3.52 (dd, 
5.5,11.0) 
3.76 (br d, 
11.0) 
61.8 61.62 3.53 (dd, 
5.5,11.0) 
3.79 (br d, 
11.0) 
62.7 62.82 3.72 (dd, 5.5, 
11.0) 
3.86 (br d, 
11.0) 
61.2 61.49 3.43 (dd, 
5.5,11.0) 
3.69 (br d, 
11.0) 
a)
Recorded in DMSO-d6,  
b)
recorded in CD3OD, *δC of vitexin [4],
 $δC of  orientin [4],  
#δC
 
of isovitexin [5],  
@δC of homoorientin [4]. 
 
Figure 2: The important HMBC correlations of compounds 1 and 3 
 97 
VJC, Vol. 53(2e), 2015                                                                                                      Phan Van Kiem, et al. 
 
By similar way, compound 4 was defined as 
homoorientin [4]. This is the first report of 
compounds 1-4 from genus Antidesma. 
 
REFERENCES 
 
1. V. V. Chi. The Dictionary of Medicinal Plants in 
Vietnam, Hanoi: Medical Publishing House, 2012: 
441-442. 
2. S. Maria, F. Islam, N. Qais, C. M. Hasan. Isolation of 
vomifoliol: a megastigmane from leaves of Antidesma 
ghaesembilla, Asian Journal of Chemistry., 25,  
3533-3534 (2013). 
3. M. F. Gargantiel, M. C. Ysrael. Antioxidant activity 
and hypoglycemic potential of Antidesma 
ghaesembilla Gaertn (Phyllantaceae), International 
Journal of Scientific and Technology Research, 3,  
422-431 (2014). 
4. D. C. Burns, D. A. Ellis, R. E. March. A predictive 
tool for assessing 13C NMR chemical shifts of 
flavonoids, Magnetic Resonance in Chemistry, 45,  
835-845 (2007). 
5. N. Ramarathnam, T. Osawa, M. Namiki, S. 
Kawakishi. Chemical studies on novel rice hull 
antioxidants. 2. Identification of isovitexin, a C-
glycosyl flavonoid, Journal of Agricultural and Food 
Chemistry, 37, 316-319 (1989). 
Corresponding author: Phan Van Kiem 
Institute of Marine Biochemistry, Vietnam Academy of Science and Technology 
18, Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam 
E-mail: phankiem@yahoo.com. 


Flavonoid glycosides from Antidesma ghaesembilla

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Flavonoid glycosides from Antidesma ghaesembilla

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