a,b
b
a
a
a,
a
School of Chemistry and Chemical Engineering, Yunnan Normal University,
Kunming 650500, China b
Department of Traditional Chinese Medicine, Yunnan University of Traditional
Chinese Medicine, Kunming 650500, China
*Corresponding author. Tel: 86-871-65941089; Email: ygchen48@126.com
From the extracts of Dimocarpus longan Lour leaves, two unusual flavonol glycosides, quercetin 3O -(3’’O -2’’’-methyl-2’’’-hydroxylethyl)-

-D-xyloside
( 1 ) and quercetin
3O -(3’’O -2’’’-methyl-2’’’-hydroxylethyl)-

-L-rhamnopyranoside ( 2 ), as well as ten known compounds including two flavonol glycosides, afzelin ( 3 ) and kaempferol-3O -

-L-rhamnopyranoside ( 4 ), two flavans, (-)-epicatechin ( 5 ) and proanthocyanidin A-2 ( 6 ), three triterpenoids, friedelin ( 7 ), epifriedelanol
( 8 ) and

-amyrin ( 9 ), a peptide,
N -benzoylphenylalanylN -benzoylphenylalaninate ( 10 ), and two sterols,

-sitosterol ( 11 ) and daucosterol ( 12 ) were isolated and identified by using combination of mass spectrometry and various 1D and 2D NMR techniques.
This is the first report of flavonoid glycosides possessing a
2-methyl-2-hydroxylethoxyl group in sugar moiety from D. longan.
Keywords: Dimocarpus longan ; Sapindaceae; flavonol glycoside

Spectroscopic data of the known compounds 3-12 .
Figure S1. Selective HMBC (H→C) correlations for compounds 1 and 2 .
Original spectra of compound 1 .
HR-TOF-MS
-TOF-MS
EIMS
1
H NMR Spectrum (400 MHz, acetoned6 )
13
C NMR Spectrum (100 MHz, acetoned6 )
COSY Spectrum
HSQC Spectrum
HMBC Spectrum
Original spectra of compound 2 .
HRTOFMS
-TOF-MS
EIMS
1
H NMR Spectrum (400 MHz, CD
3
OD)
13
C NMR Spectrum (100 MHz, CD
3
OD)
COSY Spectrum

HSQC Spectrum
HMBC Spectrum

Spectroscopic data of the known compounds 3-12 .
afzelin (3)
Yellow powder, C
21
H
20
O
11
, MW: 448; 1 H NMR (DMSO, 400 Hz) :

12.64 (1H, s,
OH-5), 10.90 (1H, br s, OH-7), 9.75 (1H, br s, OH-4′), 9.38 (1H, br s, OH-3′), 7.28
(1H, d, J= 1.6 Hz, H-2′), 7.24 (1H, dd, J= 1.8, 8.3 Hz, H-6′), 6.85 (1H, d, J= 8.3 Hz,
H-5′), 6.38 (1H, d, J= 1.6 Hz, H-8), 6.19 (1H, d, J= 1.6 Hz, H-6), 5.24 (1H, s, H-1′′),
3.11
～ 3.97 (4H, m), 0.80 (3H, d,J= 6.0 Hz, CH
3
); 13 C NMR (DMSO, 100Hz):

17.59
(q, C-6′′), 70.15 (d, C-5′′), 70.42 (d, C-2′′), 70.70 (d, C-3′′), 71.24 (d, C-4′′), 93.75 (d,
C-8), 98.79 (d, C-6), 101.90 (d, C-1′′), 104.17 (s, C-10), 115.55 (d, C-2′), 115.72
(d,C-5′), 120.81 (d, C-1′), 121.24 (s, C-6′), 134.29 (s, C-3), 145.30 (s, C-3′), 148.53 (s,
C-4′), 156.55 (s, C-2), 157.43 (s, C-9), 161.38 (s, C-5), 164.29 (s, C-7), 177.84 (s,
C-4). kaempferol-3-O-

-L-rhamnopyranoside (4)
Yellow powder, C
21
H
20
O
10
, MW: 432;
1
H NMR (CD
3
OD, 400 Hz):

7.75 (2H, d, J=
8.8 Hz, H-2′, 6′), 6.91 (2H, d, J= 8.8 Hz, H-3′, 5′), 6.36 (1H, d, J= 2.0 Hz, H-8), 6.17
(1H, d, J= 2.0 Hz, H-6), 5.36 (1H, d, J= 1.6 Hz, H-1′′), 4.20 (1H, s, H-2′′), 0.90 (3H, d,
J= 5.5 Hz, H-6′′);
13
C NMR (CD
3
OD, 100Hz):

179.66 (s, C-4), 165.92 (s, C-7),
163.25 (s, C-5), 161.60 (s, C-9), 159.32 (s, C-2), 158.59 (s, C-4′), 136.25 (s, C-3),
131.92 (d, C-6′, 2′), 122.68 (d, C-1′), 116.56 (d, C-3′, 5′), 105.97 (s, C-10), 103.54 (d,
C-1′′), 99.87 (d, C-6), 94.79 (d, C-8), 73.24 (d, C-4′′), 72.18 (d, C-3′′), 72.06 (d, C-2′′),
71.95 (d, C-5′′) , 17.67 (q, C-6′′).
(-)-epicatechin (5)
Colorless powder, C
15
H
14
O
6
, MW: 290; 1 H NMR (CD
3
OD, 400 Hz):

2.73 (1H, dd,
J= 2.8, 16.8 Hz, H-4b), 2.85 (1H, dd, J= 4.6, 16.7 Hz, H-4a), 3.34 (1H, br s, H-3),
4.81 (1H, s, H-2), 5.91 (1H, d, J= 2.3 Hz, H-6), 5.94 (1H, d, J= 2.2 Hz, H-8), 6.75 (1H, d, J= 8.2 Hz, H-5′), 6.79 (1H, dd, J= 1.8, 8.2 Hz, H-6′), 6.97 (1H, d, J= 1.6 Hz, H-2′);

13
C NMR (CD
3
OD, 100Hz):

29.25 (t, C-4), 67.45 (d, C-3), 79.83 (d, C-2), 95.85 (d,
C-8), 96.35 (d, C-6), 100.03 (s, C-10), 115.28 (d, C-2′), 115.87 (d, C-5′), 119.38 (d,
C-6′), 132.27 (s, C-1′), 145.73 (s, C-3′), 145.89 (s, C-4′), 157.34 (s, C-9), 157.63 (s,
C-5), 157.99 (s, C-7). proanthocyanidin A-2 (6)
Colorless powder, C
30
H
24
O
12
, MW: 576;
1
H NMR (CD
3
OD, 400 Hz):

2.85 (2H, m,
H-4B), 3.30 (1H, m, H-4T), 4.06 (1H, d, J= 3.4 Hz, H-3B), 4.23 (1H, s, H-2B), 4.42
(1H, d, J= 3.4 Hz, H-3T), 6.01 (1H, d, J= 2.4 Hz, H-6T), 6.08 (1H, d, J= 2.2 Hz,
H-8T), 6.10 (1H, s, H-6B), 6.80 (1H, d, J= 1.1 Hz, H-5′T), 6.82 (1H, d, J= 0.8 Hz,
H-5′B), 7.00 (2H, dd, J=8.4, 2.0 Hz, H-6′), 7.16 (2H, dd, J=2.0, 6.0 Hz, H-2′);
13
C
NMR (CD
3
OD, 100Hz):

29.17 (d, C-4T), 29.84 (t, C-4B), 66.89 (d, C-3B), 67.98 (d,
C-3T), 81.66 (d, C-2B), 96.47 (s, C-6B), 96.59 (s, C-8T), 98.26 (d, C-6T), 100.12 (d,
C-2T), 102.40 (s, C-10B), 104.23 (s, C-10T), 107.15 (s, C-8B), 115.62 (d, C-5′,2′T),
115.90 (d, C-2′B), 116.02 (d, C-5′B), 119.77 (d, C-6′T), 120.37 (d, C-6′B), 131.44 (s,
C-1′B), 132.36 (s, C-1′T), 145.57 (s, C-3′T), 145.89 (s, C-3′B), 146.20 (s, C-4′B),
146.68 (s, C-4′T), 152.07 (s, C-9B), 152.20 (s, C-7B), 154.18 (s, C-9T), 156.50 (s,
C-5B), 156.91 (s, C-5T), 158.02 (s, C-7T). friedelin (7)
Colorless neddles, C
30
H
50
O, MW: 426;
1
H NMR (CDCl
3
, 400 Hz):

0.72 (3H, s,
H-24), 0.87 (3H, s, H-25), 0.88 (3H, s, H-23), 0.95 (3H, s, H-30), 0.99 (3H, s, H-29),
1.00 (3H, s, H-26), 1.17 (3H, s, H-27), 1.18 (3H, s, H-28), 1.36 (m, H-18), 1.54 (s,
H-10), 1.44 (m, H-8), 2.55 (m, H-4); 13 C NMR (CDCl
3
, 100 Hz):

22.25 (t, C-1),
41.50 (t, C-2), 213.33 (s, C-3), 58.17 (d, C-4), 42.12 (s, C-5), 41.22 (d, C-6), 18.19 (t,
C-7), 53.05 (d, C-8), 37.38 (s, C-9), 59.40 (d, C-10), 35.57 (t, C-11), 30.46 (t, C-12),
39.64 (s, C-13), 38.24 (s, C-14), 32.70 (t, C-15), 35.95 (t, C-16), 29.95 (s, C-17),
42.71 (d, C-18), 35.29 (t, C-19), 28.14 (s, C-20), 32.36 (t, C-21), 39.21 (t, C-22), 6.81
(q, C-23), 14.62 (q, C-24), 17.92 (q, C-25), 20.23 (q, C-26), 18.65 (q, C-27), 32.05 (q,
C-28), 31.75 (q, C-29), 35.00 (q, C-30).

epifriedelanol (8)
Colorless powder, C
30
H
52
O, MW: 428;
1
H NMR (CD
3
Cl, 400 Hz):

0.86 (3H, s,
H-24), 0.93 ( 3H, s, H-25), 0.94 (3H, s, H-23), 0.96 ( 3H, s, H-30), 0.99 ( 3H, s, H-26),
1.00 (3H, s, H-29), 1.17 (3H, s, H-27), 1.17(3H, s, H-28), 3.74 (1H, brs, H-3);
13
C
NMR (CDCl
3
, 100 Hz):

16.34 (q, C-24), 35.12 (t, C-2), 72.72 (d, C-3), 49.10 (d,
C-4), 37.78 (s, C-5), 41.66 (t, C-6), 17.6 (t, C-7), 53.14 (d, C-8), 37.03 (s, C-9), 61.27
(d, C-10), 35.50 (t, C-11), 30.6 (t, C-12), 38.40 (s, C-13), 39.23 (s, C-14), 32.3 (t,
C-15), 36.02 (t, C-16), 30.0 (s, C-17), 42.74 (d, C-18 ), 35.29 (t, C-19) , 28.2 (s,
C-20 ), 32.74 (t, C-21), 39.62 (t, C-22), 11.60 (q, C-23), 15.73 (t, C-1), 18.2 (q, C-25),
18.6 (q, C-26), 20.09 (q, C-27), 31.75 (q, C-28), 35.00 (q, C-29 ), 32.04 (q, C-30).

-amyrin (9)
Colorless powder, mp. 141-142 o
C. identified by co-TLC and comparison of UV and
IR with those of authentic samples.
N -benzoylphenylalanylN -benzoylphenylalaninate (10)
Colorless neddles, C
32
H
30
O
4
N
2
, MW: 492;
1
H NMR (CDCl
3
,400 Hz):

4.91 (1H, d,
J= 6.7 Hz, H-a), 3.28 (1H, dd, J= 14.0, 6.9 Hz, H-βa), 3.22 (1H, dd, J= 13.9, 7.0 Hz,
H-βb), 4.60 (1H, m, H-a′), 3.00 (1H, dd, J= 13.7, 6.4 Hz, H-β′a), 2.89 (1H, dd, J= 13.7,
8.4 Hz, H-β′b), 4.54 (1H, dd, J= 11.3, 3.3 Hz, H-γa), 4.02 (1H, dd, J= 11.3, 4.3 Hz,
H-γb), 7.70 (2H, m, H-2, 6), 7.30 (2H, m, H-3′, 5′), 7.41 (1H, m, H-4′), 7.65 (2H, m,
H-2′, 6′), 7.37(2H, m, H-3, 5), 7.48 (1H, m, H-4), 7.28-7.20 (10H, m), 6.70 (1H, d, J=
8.4 Hz, NHb-), 6.61 (1H, d, J= 6.5 Hz, NHa-); 13 C NMR (CDCl
3
, 100 Hz):

171.91
(s, C=0), 167.42 (s, C=O), 167.21 (s, C=O), 133.27 (s, C-1), 134.16 (s, C-1′), 127.08
(d, C-2′, 6′), 127.02 (d, C-2, 6), 128.39 (d, C-3, 5), 128.63 (d, C-3′, 5′), 131.99 (d,
C-4′), 131.36 (d, C-4), 137.13 (s, C-1′), 135.74 (s, C-1), 129.26 (d, C-2′′, 6′′), 129.13
(d, C-2′′′, 6′′′), 128.83 (d, C-3′′′, 5′′′), 128.66 (d, C-3′′, 5′′), 126.76 (d, C-4′′′) , 127.34
(d, C-4′′), 65.35 (t, C-γ), 54.47 (d, C-a), 50.25 (d, C-a′), 37.54 (t, C-β), 37.26 ( t, C-β′).


-sitosterol (11)
Colorless neddles, identified by co-TLC and comparison of
1
H NMR,
13
C NMR and
EIMS with those of authentic samples. daucosterol (12)
White powder, identified by co-TLC and comparison of
1
H NMR,
13
C NMR and
EIMS with those of authentic samples.

HO
Figure S1. Selective HMBC (H→C) correlations for compounds 1 and 2
OH
OH
OH
OH
HO O
O
OH O
1
O
O
OH
O
OH
OH
OH O
O
O
H
3
C
OH
OH O
OH
2

Original spectra of compound 1 .
HR-TOF MS:

-TOF MS:

EIMS:

HNMR:

13 CNMR ：

H-H COSY ：

HSQC ：

HMBC ：

Original spectra of compound 2 .
HR-TOF MS:

-TOF MS:

EIMS:

HNMR:

13 CNMR ：

H-H COSY ：

HSQC ：

HMBC ：