Three known sterols, polypodine B (1), (22E,24R)-24-methylcholesta-2,22-diene-3β,5α,6β-triol (2) and chondrillasterol (3) were isolated from the stems of Momordica cochinchinesis (Lour.) Spreng. Their chemical structures were successfully determined using NMR and ESI-MS analysis as well as in comparison with the reported data. All compounds were reported from Momordica genus for the first time. Keywords. Momordica cochinchinesis, Cucurbitaceae, steroid

Kiem, Phan Van

Mai, Nguyen Thi

Thu, Vu Kim

English

Vietnam Academy of Science and Technology: Journals Online

  
Vietnam Journal of Chemistry, International Edition, 55(5): 606-610, 2017 
DOI: 10.15625/2525-2321.2017-00516 
606 
 
 
 
Sterols from stems of Momordica cochinchinesis (Lour.) Spreng 
 
Nguyen Thi Mai
1
, Phan Van Kiem
2*
, Vu Kim Thu
3 
1
University of Transport and Communications 
2
Institute of Marine Biochemistry, Vietnam Academy of Science and Technology 
3
Hanoi University of Mining and Geology 
Received 15-3-2017/12-8-2017; Accepted for publication 20 October 2017
 
 
 
Abstract 
Three known sterols, polypodine B (1), (22E,24R)-24-methylcholesta-2,22-diene-3β,5α,6β-triol (2) and 
chondrillasterol (3) were isolated from the stems of Momordica cochinchinesis (Lour.) Spreng. Their chemical 
structures were successfully determined using NMR and ESI-MS analysis as well as in comparison with the reported 
data. All compounds were reported from Momordica genus for the first time. 
Keywords. Momordica cochinchinesis, Cucurbitaceae, steroid. 
  
1. INTRODUCTION 
 
Momordica genus belongs to Cucurbitaceae family, 
including 60 species. In Vietnam, there are three 
species, comprising of M. charantia, M. 
cochinchinensis, and M. grosvenori. M. 
cochinchinensis is a dioecious species with yellow 
flowers, green globe fruits turn orange and red when 
ripened [1]. The main ingredient of M. 
cochinchinensis oil is β-carotene, which is used to 
treat diseases related to vitamin A as slow growth in 
children, dry eyes, night blindness, tired and 
anorexic people. Additionally, M. cochinchinensis 
oil is used in the treatment of the wound and burns. 
The seeds are used to treat abscess, mumps, swelling 
breast, engorgement, hemorrhoids and pile. The 
roots are bitter, cool thus used for preventing low-
temperature effects, diuretics [1]. The chemical 
studies of M. cochinchinensis indicated the presence 
of triterpenoids [2], carotenoids [3]. These 
compounds showed the anti-inflammatory [2], 
stomach ulcers, and wound healing activities [4]. In 
this paper, we report the isolation, structural 
elucidation of one ecdysterone and two sterols from 
the stems of M. cochinchinensis. 
 
2. MATERIAL AND METHODS 
 
2.1. Plant materials 
 
The stems of M. cochinchinensis were collected 
 in Quoc Oai, Hanoi, Vietnam in September 2013 
and identified by Prof. Dr. Ninh Khac Ban, Institute 
of Ecology and Biological Resources, VAST. A 
voucher specimen (MC1309) was deposited at the 
Herbarium of the Institute of Marine Biochemistry, 
VAST. 
 
2.2. General experimental procedures 
 
Thin layer chromatography (TLC): Performed on 
the pre-coated silica-gel DC-Alufolien 60 F254 
(Merck 1.05715), RP18 F254s plates (Merck). 
Compounds were detected by ultraviolet light at 254 
nm and 365 nm and visualized by spraying with 
aqueous 10 % H2SO4 and heating for 5 minutes. 
Column chromatography (CC): performed on 
silica gel (0.040 0.063 mm, Merck) or RP-18 resins 
(30 50 m, Fujisilisa Chemical Ltd.). 
All NMR spectra were recorded on a Bruker 
AM-500 at Institute of Chemistry, VAST.  
The ESI-MS were obtained from an Agilent 
1100 series at Institute of Marine Biochemistry, 
VAST. 
 
2.3. Extraction and isolation 
 
The dried powder of stems of M. cochinchinesis was 
extracted 3 times with methanol at 50 °C. The 
extract was filtered through filter paper, then solvent 
was removed under reduced pressure to yield 40 g of 
a dark solid extract. The extract was suspended in 
water and partitioned with dichloromethane giving 
dichloromethane (9.0 g) and water extracts (30.0 g). 
  
VJC, 55(5), 2017  Phan Van Kiem et al.  
607 
The dichloromethane extract was chromatographed 
on a silica gel column eluting with n-hexane:acetone 
(10:1→1:1, v/v) to give 5 subfractions, C1-C5.  
 
 
Figure 1: Chemical structures of compounds 1-3 
 
Fraction C2 was chromatographed on an RP-18 
column eluting with acetone–water (6:1, v/v) to give 
two smaller fractions, C2.1 and C2.2. Compound 3 
(5.0 mg) was yielded from C2.2 fraction using a silica 
gel column eluting with n-hexane:acetone (2:1, v/v). 
Fraction C3 (1.2 g) was chromatographed on an RP-
18 column eluting with acetone - water (2:1, v/v) to 
give four smaller fractions, C3.1-C3.4. Fraction C3.2 
was chromatographed on a Sephadex LH-20 column 
eluting with dichloromethane:methanol (1:3, v/v) to 
yield compound 2 (10.0 mg). Fraction C4 (1.5 g) was 
continued to fractionated on a silica gel column 
eluting with dichloromethane:methanol:water 
(5:1:0.1, v/v/v) to give two fractions, C4.1 and C4.2. 
Fraction C4.1 (600 mg) was chromatographed on a 
RP-18 column eluting with acetone:methanol:water 
(4:4:1 v/v/v) to yield compound 1 (15.0 mg).  
 
Polypodine B (1): White amorphous powder; 
ESI-MS m/z 495 [M-H]
-
; C27H44O8; 
1
H-NMR (500 
MHz, CD3OD) and 
13
C-NMR (125 MHz, CD3OD), 
see Table 1. 
(22E,24R)-24-Methylcholesta-2,22-diene-
3β,5α,6β-triol (2): White amorphous powder; ESI-
MS m/z 429 [M-H]
-
; C28H46O3; 
1
H-NMR (500 MHz, 
DMSO-d6) and 
13
C-NMR (125 MHz, DMSO-d6), 
see table 1. 
Chondrillasterol (3): White amorphous powder; 
ESI-MS m/z 411 [M-H]
-
; C29H48O; 
1
H-NMR (500 
MHz, CDCl3) δH: 3.59 (m, H-3), 5.16 (m, H-7), 0.55 (s, 
H-18), 0.80 (s, H-19), 1.03 (d, J = 6.5 Hz, H-21), 5.03 
(dd, J = 8.5, 16.0 Hz, H-22), 5.19 (dd, J = 8.5, 16.0 Hz, 
H-23), 0.79 (d, J = 6.5 Hz, H-26), 0.85 (d, J = 6.5 Hz, 
H-27), 0.81 (t, J = 7.5 Hz, H-29); 
13
C-NMR (125 MHz, 
CDCl3) δC: 38.0 (C-1), 31.5 (C-2), 71.1 (C-3), 37.2 (C-
4), 40.3 (C-5), 29.7 (C-6), 117.5 (C-7), 139.6 (C-8), 
49.5 (C-9), 34.2 (C-10), 21.6 (C-11), 39.5 (C-12), 43.3 
(C-13), 55.1 (C-14), 23.0 (C-15), 28.4 (C-16), 55.9 (C-
17), 12.1 (C-18), 13.1 (C-19), 40.8 (C-20), 20.9 (C-21), 
138.1 (C-22), 129.5 (C-23), 51.2 (C-24), 31.8 (C-25), 
18.8 (C-26), 21.4 (C-27), 25.4 (C-28), 12.4 (C-29). 
 
3. RESULTS AND DISCUSSION 
 
Compound 1 was obtained as a white amorphous 
powder. The 
1
H-NMR spectrum of 1 showed the 
signals of five methyl groups at 0.92 (3H, s), 0.94 
(3H, s), 1.21 (3H, s), and 1.22 (6H, s), one olefinic 
proton at δH 5.88 (1H, t, J = 7.5 Hz), and three 
oxymethine protons at δH 3.33 (m), 3.97 (m), and 
4.00 (br d, J = 3.0 Hz). The 
13
C-NMR and DEPT 
spectra of 1 exhibited the signals of 27 carbons, 
including one carbonyl carbon at δC 202.4; seven 
non-protonated carbons at δC 45.4, 48.5, 71.3, 77.9, 
80.3, 84.1, and 167.5; six methines at δC 39.0, 50.4, 
68.4, 70.2, 78.4, and 120.6; eight methylenes at δC 
21.5, 22.5, 27.4, 31.7, 32.6, 34.2, 36.2, and 42.4; 
five methyl carbons at δC 16.9, 18.0, 21.0, 29.0, and 
29.7. Analysis the NMR data of compound 1 
indicated that structure of 1 was ecdysteroid skeleton 
and very similar to those of polypodine B [5]. The 
position of functional groups was assigned by 
HMBC correlations as well as compared with those 
of reference compounds. The HMBC correlations 
from H-2 (δH 3.97) to C-1 (δC 34.2)/C-3 (δC 70.2)/C-
4 (δC 36.2)/C-10 (δC 45.4); from H-3 (δH 4.01) to C-
1 (δC 34.2)/C-2 (δC 68.4)/C-4 (δC 36.2)/C-5 (δC 
80.3); from H-19 (δH 0.94) to C-1 (δC 34.2)/C-5 (δC 
80.3)/C-9 (δC 39.0)/C-10 (δC 45.4) suggested 
hydroxyl groups at C-2, C-3, and C-5. The HMBC 
correlations between H-7 (δH 5.88) and C-5 (δC 
80.3)/C-6 (δC 202.4)/C-8 (δC 167.5)/C-9 (δC 39.0)/C-
  
VJC, 55(5), 2017  Sterols from stems of Momordica cochinchinesis … 
608 
14 (δC 84.1) suggested the position of carbonyl 
group at C-6 and the double bond at C-7/C-8. The 
HMBC correlations from H-18 (δH 0.92) to C-12 (δC 
32.6)/C-13 (δC 48.5)/C-14 (δC 84.1)/C-17 (δC 50.4) 
suggested the hydroxyl groups at C-14. Three 
hydroxyl groups at C-20, C-22, and C-25 were also  
Table 1: The 
1
H- and 
13
C-NMR data for compounds 1 and 2 and reference compounds 
C 1 2 
δC
$ δC
a δH
a
 mult. (J, Hz) δC  δC
b δH
b
 mult. (J, Hz) 
1 34.9 34.2 1.70 (m) 33.6 31.2 1.24 (m)/1.61 (m) 
2 68.1 68.4 3.97 (m) 33.9 32.5 1.30 (m) 
3 69.9 70.2 4.01 (br d, 3.0) 67.6 66.0 3.77 (m) 
4 36.1 36.2 1.78
 
(m)/2.10 (dd, 3.0, 15.0) 41.9 40.2 1.50 (m)/1.89 (m) 
5 79.9 80.3 2.41 (m) 76.2 74.5 - 
6 201.0 202.4 - 74.3 72.1 3.39 (m) 
7 119.9 120.6 5.88 (d, 2.5) 120.5 119.4 5.08 (t, 2.5) 
8 167.0 167.5 - 141.6 139.7 - 
9 38.4 39.0 3.20 (t, 8.5) 43.8 42.3 1.93 (m) 
10 44.8 45.4 - 38.1 36.7 - 
11 22.1 22.5 1.78 (m)/1.83(m) 22.5 21.3 1.42 (m) 
12 32.2 32.6 1.91(m)/2.16 (m) 40.0 39.0 1.14 (m)/1.88 (m) 
13 48.2 48.5 - 43.8 43.0 - 
14 84.1 84.1 - 55.3 54.2 1.80 (m) 
15 31.8 31.7 1.61 (t, 10.0)/1.98 (m) 23.5 22.6 1.37 (m)/1.50 (m) 
16 21.4 21.5 2.00 (m)/1.75 (m) 28.5 27.7 1.24 (m)/1.57 (m) 
17 50.1 50.4 2.41 (t, 9.0) 56.12 55.3 1.26 (m) 
18 18.0 18.0 0.92 (s) 12.6 12.1 0.54 (s)  
19 17.3 16.9 0.94 (s) 18.8 17.7 0.90 (s) 
20 76.9 77.9 - 40.8 40.1 2.01 (m) 
21 21.7 21.0 1.22 (s) 21.5 21.0 0.99 (d, 6.5) 
22 77.7 78.4 3.33 (m) 136.2 135.4 5.19 (dd, 8.0, 16.0) 
23 27.6 27.4 1.78 (m)/1.31 (m) 132.2 131.4 5.25 (dd, 7.0, 16.0) 
24 42.3 42.4 1.82 (m)/1.46(m) 43.2 42.0 1.85 (m) 
25 69.7 71.3 - 33.4 32.5 1.47 (m) 
26 30.1 29.0 1.21 (s) 20.2 19.7 0.83 (d, 7.0) 
27 30.2 29.7 1.22 (s) 19.9 19.5 0.81 (d, 7.0) 
28 24.2 24.3 0.88 (s) 17.9 17.3 0.89 (d, 6.5) 
29 28.0 28.0 0.97 (s)    
30 22.1 22.1 0.87 (s)    
a) 
Recorded in CD3OD; 
b)
DMSO-d6; 
$δC of polypodine B in pyridine-d5 [5];  
#δC
 
of (22E,24R)-24-methylcholesta-2,22-diene-3β,5α,6β-triol [6]. 
 
confirmed by HMBC correlations between H-21 (δH 
1.22) and C-17 (δC 50.4)/C-20 (δC 77.9)/C-22 (δC 
78.4); between H-26 (δH 1.21)/H-27 (δH 1.22) and C- 
25 (δC 71.3). The NMR data of 1 were in good 
agreement with those of polypodine B [5]. Thus, the 
structure of 1 was elucidated as polypodine B. 
  
VJC, 55(5), 2017  Phan Van Kiem et al.  
609 
Compound 2 was obtained as a white amorphous 
powder. The 
1
H-NMR spectrum of 2 
showed the signals of two tertiary methyl groups at δH 
0.54 (3H, s) and 0.90 (3H, s), four secondary methyl 
groups at δH 0.81 (3H, d, J = 7.0 Hz), 0.83 (3H, d, J = 
7.0 Hz), 0.89 (3H, d, J = 6.5 Hz), and 0.99 (3H, d, J = 
6.5 Hz). The olefin proton signals at δH 5.19 (1H, dd, 
J = 8.0, 16.0 Hz) and 5.25 (1H, dd, J = 7.0, 16.0 Hz) 
suggested the presence of a double bond in E 
configuration. The 
13
C-NMR and DEPT spectra of 2 
exhibited the signals of 28 carbons, including four 
non-protonated carbons at δC 139.7, 74.5, 43.0 and 
36.7; eleven methines at δC 135.4, 131.4, 119.4, 72.1, 
66.0, 55.3, 54.2, 42.3, 42.0, 40.1, 32.5; seven 
methylenes at δC 40.2, 39.0, 32.5, 31.2, 27.7, 22.6, 
and 21.3; six methyl carbons at δC 21.0, 19.7, 19.5, 
17.7, 17.3 and 12.1. The above spectral data analysis 
suggested the structure of compound 2 as a sterol. 
The NMR data of 2 were in good agreement with 
those of 3β, 5α, 6β-trihydroxysterol reported in the 
literature [6]. In addition, the HMBC correlations 
between H-19 (δH 0.90) and C-1 (δC 31.2)/C-5 (δC 
74.5)/C-9 (δC 42.3)/C-10 (δC 36.7); between H-7 (δH 
5.08) and C-6 (δC 72.1)/C-8 (δC 139.7)/C-9 (δC 
42.3)/C-14 (δC 54.2) suggested the position of two 
hydroxyl groups at C-5, C-6 and double bond at the 
C-7/C-8. The double bond at C-22/C-23 was 
confirmed by HMBC correlations from H-21 (δH 
0.99) to C-17 (δC 55.3)/C-20 (δC 40.1)/C-22 (δC 
135.4); from H-28 (δH 0.89) to C-23 (δC 131.4)/C-24 
(δC 42.0)/C-25 (δC 32.5). From the above evidence 
and comparison with the reported data [6], compound 
2 was determined as (22E,24R)-24-methylcholesta-
2,22-diene-3β,5α,6β-triol. .
 
Figure 2: The key HMBC correlations of compounds 1 and 2 
 
The molecular formula of 3 was suggested as 
C29H48O (M = 412) by the ESI-MS ion peak at m/z 
411 [M-H]
-
 and NMR data. The 
1
H-NMR 
spectrum of 3 showed signals for 6 methyl groups at 
δH 0.55 (3H, s), 0.79 (3H, d, J = 6.5 Hz), 0.80 (3H, 
s), 0.81 (3H, t, J = 7.5 Hz), 0.85 (3H, d, J = 6.5 Hz) 
and 1.03 (3H, d, J = 6.5 Hz). Besides, the presence 
of two olefin proton signals at δH 5.19 (1H, dd, J = 
8.5, 16.0 Hz) and 5.03 (1H, dd, J = 8.5, 16.0 Hz) 
indicated the E configuration for this double bond. 
The 
13
C-NMR and DEPT spectra of 3 displayed 
signals of 29 carbons, including three quaternary 
carbons at δC 139.6, 43.3, 34.2; eleven methines at 
δC 138.1, 129.5, 117.5, 71.1, 55.9, 55.1, 51.2, 49.5, 
40.8, 40.3 and 31.8; nine methylenesat δC 39.5, 38.0, 
37.2, 31.5, 29.7, 28.4, 25.4, 23.0, and 21.6; six 
methyl carbons at δC 21.4, 20.9, 18.8, 13.1, 12.4, and 
12.1. From the above evidence and comparison with 
the reported data [7], compound 3 was determined as 
chondrillasterol. This is the first time compounds 1-
3 were isolated from genus Momordica. 
 
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Corresponding author: Phan Van Kiem 
Institute of Marine Biochemistry 
Vietnam Academy of Science and Technology 
No. 18, Hoang Quoc Viet, Cau Giay, Hanoi 
E-mail: phankiem@vast.vn. 


Sterols from stems of Momordica cochinchinesis (Lour.) Spreng.

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Sterols from stems of Momordica cochinchinesis (Lour.) Spreng.

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