Limonoids and tirucallane derivatives from the seeds of a krishna mangrove, xylocarpus moluccensis

Article abstract of DOI:10.1021/np900823c

Six new phragmalins, moluccensins H-M (1-6), two new andirobin-type limonoids, moluccensins N and O (7, 8), and two new tirucallane derivatives, moluccensins P and Q (9, 10), were isolated from seeds of an Indian mangrove, Xylocarpus moluccensis, together with the known compound 3β,22S- dihydroxytirucalla-7,24-dien-23-one. The structures of these compounds were established on the basis of spectroscopic data. Moluccensins H-L were phragmalins with a C-30 carbonyl group, and moluccensin M was a unique ring-D-opened 16-norphragmalin. Moluccensins H-J possess conjugated Δ^8,9 and Δ^14,15 double bonds, moluccensins K and L contain a Δ^8,14 double bond, and moluccensin M has a characteristic C₁₅-C₃₀ linked five-membered lactone ring. Moluccensins H and I showed moderate insecticidal activity against the fifth instar larvae of Brontispa longissima (Gestro) at a concentration of 100 mg/L.

Full text of DOI:10.1021/np900823c

644
J. Nat. Prod. 2010, 73, 644–649
Limonoids and Tirucallane Derivatives from the Seeds of a Krishna Mangrove, Xylocarpus
moluccensis
Jun Wu,*,† Sheng-Xin Yang,‡ Min-Yi Li,†,⊥ Gang Feng,§ Jian-Yu Pan,| Qiang Xiao,∇ Jari Sinkkonen,O and
Tirumani Satyanandamurty¶
Key Laboratory of Marine Bio-resources Sustainable Utilization, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164
West Xingang Road, Guangzhou 510301, People’s Republic of China, College of Chinese Medicinal Materials, Jilin Agricultural UniVersity,
Changchun 130118, People’s Republic of China, EnVironment and Plant Protection Institute, Academy of Tropical Agriculture Sciences of
China, Danzhou in Hainan ProVince, 571737, People’s Republic of China, Graduate UniVersity of Chinese Academy of Sciences, 19 Yuquan
Road, Beijing 100049, People’s Republic of China, Institute of Medicinal Plant DeVelopment, Chinese Academy of Medical Sciences and
Peking Union Medical College, Beijing 100094, People’s Republic of China, Institute of Organic Chemistry, Jiangxi Science & Technology
Normal UniVersity, Nanchang 330013, People’s Republic of China, Laboratory of Organic Chemistry and Chemical Biology, Department of
Chemistry, UniVersity of Turku, Turku 20014, Finland, and GoVernment Degree College at Amadala Valasa, Srikakulam District,
Andhra Pradesh, India
ReceiVed December 18, 2009
Six new phragmalins, moluccensins H-M (1-6), two new andirobin-type limonoids, moluccensins N and O (7, 8), and
two new tirucallane derivatives, moluccensins P and Q (9, 10), were isolated from seeds of an Indian mangrove, Xylocarpus
moluccensis, together with the known compound 3ꢀ,22S-dihydroxytirucalla-7,24-dien-23-one. The structures of these
compounds were established on the basis of spectroscopic data. Moluccensins H-L were phragmalins with a C-30
carbonyl group, and moluccensin M was a unique ring-D-opened 16-norphragmalin. Moluccensins H-J possess conjugated
∆
8,9 and ∆14,15 double bonds, moluccensins K and L contain a ∆8,14 double bond, and moluccensin M has a characteristic
C15-C30 linked five-membered lactone ring. Moluccensins H and I showed moderate insecticidal activity against the
fifth instar larvae of Brontispa longissima (Gestro) at a concentration of 100 mg/L.
Limonoids, triterpene derivatives from a precursor with a 4,4,8-
trimethyl-17-furanylsteroid skeleton, have been found only in plants
of the order Rutales. They are classified by the type of foursusually
highly oxidizedsrings (designated as A, B, C, and D) in the intact
Pradesh. In the current paper, we present the isolation and
characterization of five additional phragmalins (1-5), each with a
C-30 carbonyl group, and a unique ring-D-opened 16-norphragmalin
(6), from seeds of the same Indian mangrove, X. moluccensis (Lam.)
M Roem. (Meliaceae), together with two new andirobin-type
limonoids (7, 8), two new tirucallane derivatives (9, 10), and the
known compound 3ꢀ,22S-dihydroxytirucalla-7,24-dien-23-one.15
The structures of these compounds were established on the basis
of spectroscopic data or comparison with data in the literature. The
new compounds were tested for insecticidal activity against the fifth
instar larvae of Brontispa longissima (Gestro) at a concentration
of 100 mg/L.
1
triterpene. Phragmalins, such as pseudrelones A1 and A2 isolated
from Pseudocedrela kotschyii and khayanolides A-C2 from Khaya
senegalensis, have characteristic tricyclo[3.3.12,10.11,4]decane or
tricyclo[4.2.110,30.11,4]decane ring systems.
The family Meliaceae has proved to produce a variety of
antifeedant limonoids, such as azadirachtin3 from the neem tree,
Azadiracha indica, and harrisonin4 from Harrisonnia abyssinica.
Two meliaceous mangroves, Xylocarpus granatum and X. moluc-
censis, are known for producing antifeedant limonoids, especially
phragmalins and mexicanolides. Previous investigations on seeds
of these two species yielded an andirobin, two phragmalins, three
gedunins, and 14 mexicanolides, including xyloccensins A-K.5-9
Previously we have reported the isolation and identification of eight
unique 8,9,30-phragmalin ortho esters and 13 limonoids with a new
carbon skeleton from the bark and seeds of a Chinese mangrove,
X. granatum.10-12 To date, 42 mexicanolides and 23 phragmalins,
including three 1,8,9-phragmalin ortho esters, eight 8,9,30-phrag-
malin ortho esters, and 12 polyhydroxylated phragmalins, have been
isolated from the wood, seeds, and fruits of X. granatum and X.
moluccensis.13 We recently identified seven phragmalins, moluc-
censins A-G,14 from seeds of an Indian mangrove, X. moluccensis,
collected in the mangrove wetlands of Krishna estuary, Andhra
* To whom correspondence should be addressed. Tel: (86-20) 8445-
8442. Fax: (86-20) 8445-1672. E-mail: wwujun2003@yahoo.com.
† South China Sea Institute of Oceanology, Chinese Academy of
Sciences.
Results and Discussion
‡ Jilin Agricultural University.
§ Academy of Tropical Agriculture Sciences of China.
⊥ Graduate University of Chinese Academy of Sciences.
| Chinese Academy of Medical Sciences and Peking Union Medical
College.
Compound 1 had the molecular formula C36H44O11, as established
by HR-TOFMS (m/z 675.2770, calcd for [M + Na]+ 675.2776),
indicating 15 degrees of unsaturation. The H and 13C NMR data
1
of 1 (Tables 1 and 2) indicated that nine of the 15 elements of
unsaturationcamefromaconjugatedketonegroup,fourcarbon-carbon
double bonds, and four ester functionalities. Therefore, the molecule
∇ Jiangxi Science & Technology Normal University.
O University of Turku.
¶ Government Degree College at Amadala Valasa.
10.1021/np900823c  2010 American Chemical Society and American Society of Pharmacognosy
Published on Web 02/10/2010

Limonoids from Xylocarpus moluccensis
Journal of Natural Products, 2010, Vol. 73, No. 4 645
Table 1. 1H NMR (500 MHz) Data (δ) for Moluccensins H-L
(1-5) in CDCl3 (J in Hz)
Table 2. 13C NMR (125 MHz) Data (δ) for Moluccensins H-L
(1-5) in CDCl3
position
1
2
3
4
5
position
1
2
3
4
5
3
5
5.05 s
2.84 m
2.51a
5.07 s
2.82 m
2.51a
5.34 s
5.28 s
5.15 s
1
2
3
4
5
6
7
8
90.9 qC
79.2 qC
87.3 CH
45.1 qC
44.2 CH
90.8 qC
79.1 qC
87.2 CH
45.1 qC
44.3 CH
86.7 qC
88.8 qC
82.2 CH
46.4 qC
43.4 CH
88.5 qC
91.1 qC
83.9 CH
45.3 qC
90.4 qC
80.1 qC
89.1 CH
43.6 qC
2.80 m
2.96 br d, 10.0 2.95 d, 9.5
6a
6b
9
11R
11ꢀ
12R
2.50a
2.37 br s
2.37 d, 10.0
2.64 br s
1.78 m
1.78 m
1.50 m
2.35 br s
2.35 d, 9.5
2.78 br s
1.77 m
1.67 m
1.71 m
2.44a
2.44a
2.40a
37.6 CH2 39.2 CH
2.38a
2.38a
2.39a
2.39a
2.44 m
2.40a
33.2 CH2 33.2 CH2 33.4 CH2 34.0 CH2 34.0 CH
173.0 qC 173.0 qC 173.1 qC 173.6 qC 173.3 qC
122.0 qC 122.0 qC 122.9 qC 130.7 qC 130.6 qC
152.3 qC 152.4 qC 152.3 qC 40.3 CH
48.6 qC 48.6 qC 49.9 qC 48.6 qC
25.1 CH2 25.1 CH2 25.4 CH2 18.9 CH2 19.9 CH2
30.2 CH2 30.1 CH2 29.8 CH2 29.4 CH2 30.5 CH2
36.5 qC
1.69 br d, 1.66 br d, 1.64 m
12.4
1.48 m
7.25, s
12.4
1.47 m
7.25, s
9
44.7 CH
47.8 qC
12ꢀ
15
1.43 m
7.30, s
1.25 m
1.33 m
3.91 br s
10
11
12
13
14
15
16
17
18
19
20
21
22
23
28
29
30
7-OMe
3.93 d, 16.5
3.85 dd, 16.5,
4.0
5.43 s
1.20 s
1.14 s
7.51 br s
6.44 br s
36.5 qC
36.7 qC
38.8 qC
39.1 qC
17
18
19
21
22
23
28
5.02 s
1.03 s
1.11 s
5.02 s
1.03 s
1.11 s
5.05 s
1.03 s
1.25 s
5.48 s
1.20 s
1.10 s
7.51 br s
6.45 br s
7.43, br s
0.86 s
2.24 d, 11.5
2.02 d, 11.5
3.65 s
167.0 qC 167.3 qC 167.0 qC 145.6 qC 146.3 qC
115.9 qC 115.8 qC 116.2 qC 35.0 CH2 36.3 CH2
165.5 qC 165.5 qC 165.7 qC 168.6 qC 168.7 qC
7.51 br s 7.50 br s 7.51 br s
6.47 br s 6.46 br s 6.46 br s
7.44, br s 7.44, br s 7.44, br s 7.42, br s
80.3 CH
80.3 CH
80.3 CH
79.8 CH
79.9 CH
15.7 CH3 15.7 CH3 16.0 CH3 17.8 CH3 18.9 CH3
16.2 CH3 16.2 CH3 16.6 CH3 18.0 CH3 18.0 CH3
120.1 qC 120.1 qC 120.1 qC 120.3 qC 120.2 qC
141.3 CH 141.3 CH 141.3 CH 141.8 CH 141.7 CH
110.1 CH 110.1 CH 110.1 CH 109.8 CH 109.7 CH
143.1 CH 143.1 CH 143.1 CH 143.2 CH 143.3 CH
16.4 CH3 16.4 CH3 16.5 CH3 14.7 CH3 14.6 CH3
41.5 CH2 41.5 CH2 41.6 CH2 40.9 CH2 41.7 CH2
193.1 qC 193.1 qC 186.8 qC 193.1 qC 198.1 qC
52.1 CH3 52.1 CH3 52.1 CH3 52.0 CH3 52.0 CH3
0.98 s
0.98 s
2.39a
2.39a
3.69 s
0.95 s
0.86 s
29pro-S 2.39a
29pro-R 2.39a
7-OMe 3.70 s
2-OH 4.69 br s 4.69 br s
3-Acyl
2′
3′
2.02 d, 11.0 2.07 d, 11.0
1.81 d, 11.0 1.61 d, 11.0
3.70 s
3.66 s
4.51 br s
2.46 m
1.12 d, 7.0 1.40 m
1.60 m
1.14 d, 7.0 0.86 t, 7.5 1.14 d, 7.0 1.16 d, 7.0
1.10 d, 7.0
1-Acyl
2.29 m
1.38 m
1.58 m
2.28 m
2.51 m
1.14 d, 7.0 1.13 d, 7.0
2.32 m
2.07 m
1.38 m
1.60 m
0.88 t, 7.5
1.14 d, 7.0
1-Acyl
2.33 m
1.41 m
3-Acyl-1′ 175.0 qC 174.0 qC 174.5 qC 175.7 qC 175.7 qC
4′
5′
Acyl
2′′
3′′
2′
34.2 CH
41.3 CH
34.2 CH
34.2 CH
41.3 CH
3′
18.8 CH3 26.4 CH2 18.9 CH3 18.2 CH3 25.8 CH2
19.1 CH3 11.6 CH3 18.9 CH3 19.9 CH3 11.2 CH3
1-Acyl
2.48 m
1.08 d, 7.0 1.55 m
1.80 m
2-Acyl
2.53 m
2-Acyl
2.53 m
1.53 m
1.80 m
4′
5′
16.7 CH3
1-Acyl
17.6 CH3
1-Acyl
Acyl
1′′
2′′
3′′
4′′
5′′
1-Acyl
2-Acyl
2-Acyl
1.62 m
0.89 t, 7.5
1.11 d, 7.0
175.3 qC 175.6 qC 178.0 qC 179.1 qC 176.2 qC
41.3 CH 34.2 CH 41.4 CH 41.5 CH 41.0 CH
26.5 CH2 18.9 CH3 26.7 CH2 26.7 CH2 26.6 CH2
11.6 CH3 19.0 CH3 11.6 CH3 11.6 CH3 11.6 CH3
4′′
5′′
0.85 t, 7.5 1.08 d, 7.0 1.00 t, 7.5 1.01 t, 7.5
1.06 d, 6.5 1.24 d, 6.5 1.26 d, 6.0
a Overlapped signals assigned by 1H-1H COSY, HSQC, and HMBC
16.7 CH3
16.7 CH3 16.7 CH3 16.7 CH3
spectra without designating multiplicity.
and C-30. Moreover, a ∆8,9 double bond was established by HMBC
correlations between H-15/C-8, H3-19/C-9, and H2-11/C-9, and a
C-30 ketone function was suggested by those between H-15/C-30,
2-OH/C-30, H-3/C-30, and H-29/C-30 (Figure S1). Connections
of the five fragments CH2-11-CH2-12, CH-5-CH2-6, CH-22-CH-
23, CH3-3′-CH-2′-CH3-4′, and CH3-4′′-CH2-3′′-CH-2′′-CH3-
5′′ were confirmed by the corresponding five homonuclear proton-
was hexacyclic. DEPT experiments revealed that 1 had eight methyl
(a methoxy, a primary methyl, three secondary methyls, and three
tertiary methyls of the phragmalin nucleus), five methylene, nine
methine (four olefinic), and 14 quaternary carbons (five carbonyls).
The NMR data of 1 (Tables 1 and 2) and its 2D NMR studies
(1H-1H COSY, HSQC, and HMBC) (Figure S1) indicated the
presence of a methoxycarbonyl group (δH 3.70 s, δC 52.1 CH3,
173.0 qC), an isobutyryl group [δH 2.46 m, 1.12 (d, J ) 7.0 Hz),
1.14 (d, J ) 7.0 Hz); δC 18.8 CH3, 19.1 CH3, 34.2 CH, 175.0 qC],
a 2-methylbutyryl group [δH 0.85 (t, J ) 7.5 Hz), 1.06 (d, J ) 6.5
Hz), 1.38, m, 1.58, m, 2.29, m; δC 11.6 CH3, 16.7 CH3, 26.5 CH2,
41.3 CH, 175.3 qC], and a ꢀ-furanyl ring (δH 6.47 br s, 7.44 br s,
7.51 br s; δC 110.1 CH, 120.1 qC, 141.3 CH, 143.1 CH). An R,
ꢀ-unsaturated δ-lactone ring D, characterized by the following NMR
data [δH 5.02 s, 7.25 s; δC 80.3 CH, 36.5 qC, 167.0 qC, 115.9 CH,
165.5 qC] (Tables 1 and 2), was confirmed by HMBC correlations
between H-15/C-14, H-15/C-16, H-17/C-13, H-17/C-14, and H-17/
C-16 (Figure S1). The above NMR data and the 2D NMR studies
suggested that 1 was a phragmalin.
Protons of a tertiary methyl group (δH 1.03 s; δC 15.7), showing
HMBC correlations to C-12, C-13, C-14, and C-17 (Figure S1),
were assigned to H3-18. Protons of the second tertiary methyl group
(δH 1.11 s; δC 16.2), exhibiting HMBC correlations to C-1, C-5,
C-9, and C-10, were identified as H3-19, and those of the third
tertiary methyl group (δH 0.98 s; δC 16.4), showing HMBC
correlations to C-3, C-4, and C-5 (Figure S1), were assigned to
H3-28. Protons [δH 2.39a and 2.39a] of a methylene group (δC 41.5),
exhibiting HMBC correlations to C-1, C-2, C-3, and C-4 (Figure
S1), were identified as H2-29. An OH group (δH 4.69 br s) located
at C-2 was confirmed by its strong HMBC correlations to C-2, C-3,
1
proton spin systems observed in the H-1H COSY spectrum of 1
(Figure S1). The strong HMBC correlation from H-3 (5.05, s) to
C-1′ (175.0 qC) of an isobutyryl group disclosed its location at
C-3. The 2-methylbutyryl group, however, was suggested to be
attached to C-1 by its downshifted chemical shift (δC 90.9), being
lower than 90 ppm.14
The relative configuration of 1 was established on the basis of
the NOESY interactions. The significant NOE interaction (Figure
S2) from H-3 to Hpro-R-29 helped to establish this 3R-H and the
corresponding 3ꢀ-isobutyryl group. NOE interactions between H-5/
H-11ꢀ and H-5/H-17 established the ꢀ-orientation of H-5 and H-17.
Similarly, those between H3-18/H-11R and H3-18/H-15 indicated
the R-orientation of H3-18. Thus, the relative configuration of the
phragmnalin nucleus of 1, named moluccensin H, was established
as shown in Figure S2. On the basis of the result that the literature
specific rotation of (R)-2-methylbutyric acid is negative (-14.3)16
and that of (S)-2-methylbutyric acid is positive (+19.3, 18.9),17,18
the absolute configuration at C-2 in the 2-methylbutyryl group of
1 could be determined according to the specific rotation of its acid,
which was obtained as a 1:1 mixture with isobutanoic acid from
the alkaline hydrolysis of 1. Since isobutanoic acid is optically
inactive, the absolute configuration at C-2 in methylbutyric acid

646 Journal of Natural Products, 2010, Vol. 73, No. 4
Wu et al.
was suggested to be S from the RD value ([R]25 +10 (c 0.06,
Table 3. 1H (400 MHz) and 13C (100 MHz) NMR Data for
Moluccensin M (6)a
D
Me2CO)) of this mixture.
Moluccensin I (2), a white, amorphous powder, had the same
molecular formula as that of moluccensin H (1). The NMR data of
2, indicating the presence of isobutyryl and 2-methylbutyryl groups,
were similar to those of 1. However, those of the isobutyryl and
2-methylbutyryl groups were slightly different. A strong HMBC
correlation from H-3 (5.07, s) to C-1′ (174.0 qC) of the 2-meth-
ylbutyryl group placed it at C-3, whereas the isobutyryl group was
attached to C-1, as suggested by its downshifted chemical shift (δC
90.8).14 Thus, the structure of moluccensin I was established as
shown in 2.
δH J (Hz)
acetone-d6
δC
δH J (Hz)
δC
position
acetone-d6
CDCl3
CDCl3
1
2
3
4
5
6
90.6 qC
78.6 qC
84.0 CH
44.7 qC
36.0 CH
33.4 CH2
90.3 qC
78.7 qC
84.9 CH
44.7 qC
36.1 CH
34.0 CH2
5.13 s
5.06 s
2.54b
2.48b
2.28 d, 10.0
2.30 br s
2.43 d, 12.0
2.55b
7
8
9
10
11R
11ꢀ
12R
12ꢀ
13
14
15
17
18
19
20
21
22
23
28
29pro-R
29pro-S
30
7-OMe
2-OH
17-OH
3-Acyl
1′
2′
3′
173.4 qC
162.2 qC
40.2 CH
51.2 qC
172.8 qC
160.8 qC
40.2 CH
51.7 qC
2.73 m
2.57b
The molecular formula of compound 3 was determined to be
the same as that of 1, and the NMR data of 3 were similar to those
of 1. Isobutyryl and 2-methylbutyryl groups were present, and the
location of the isobutyryl group [δH 2.51 m, 1.14 (d, J ) 7.0 Hz),
1.14 (d, J ) 7.0 Hz); δC 18.9 CH3, 18.9 CH3, 34.2 CH, 174.5 qC]
(Tables 1 and 2) at C-3 in ꢀ-orientation was again deduced by
1H-1H COSY, HMBC, and NOE correlations. The 2-methylbutyryl
group, however, was present at C-2 by the downfield shift of C-2
(δC 88.8) and the upfield shift of C-1 (δC 86.7). The relative
configuration of 3 was the same as that of 1 on the basis of NOE
interactions. Therefore, the structure of moluccensin J (3) was
identified as 2-O-2S-methylbutyryl-1-de-2-methylbutyrylmoluc-
censin H.
1.94 m
1.76 m
1.68 m
1.35 m
19.6 CH2
1.85 m
1.65 m
1.72 m
1.28 m
19.8 CH2
34.7 CH2
34.7 CH2
39.3 qC
39.5 qC
133.0 qC
175.6 qC
72.3 CH
17.1 CH3
17.4 CH3
125.8 qC
140.9 CH
110.2 CH
142.6 CH
14.6 CH3
38.4 CH2
134.0 qC
175.3 qC
72.5 CH
17.6 CH3
17.8 CH3
125.1 qC
141.0 CH
109.9 CH
142.9 CH
15.0 CH3
38.7 CH2
5.09 s
1.25 s
1.16 s
5.05 s
1.32 s
1.11 s
7.53 br s
6.53 br s
7.52 br s
0.80 s
2.48 d, 11.6
2.66 d, 11.6
5.13 s
7.48 br s
6.48 br s
7.41 br s
0.80 s
2.50 d, 11.6
2.57 d, 12.4
5.04 s
3.64 s
3.49 br s
4.15 br s
Compound 4 had the molecular formula C36H46O11, as established
by HR-TOFMS, two mass units more than 3. The NMR data of 4
were similar to those of 3, except for the lack of ∆8,9 and ∆14,15
double bonds. However, a ∆8,14 double bond was established by
HMBC correlations between H2-15/C-8, H2-15/C-14, H-9/C-8, and
H-9/C-14 (Figure S3). The existence of this double bond was
corroborated by strong homoallylic coupling between H2-15 and
H-9 observed in the 1H-1H COSY spectrum. The significant NOE
interaction observed in 4 (Figure S4) from H-3 to Hpro-R-29 helped
to establish the 3R-H and the corresponding 3ꢀ-isobutyryl group.
Moreover, NOE interactions between H-5/H-15ꢀ, H-5/H-17, and
H-17/H-12ꢀ established the ꢀ-orientation of H-5 and H-17.
Similarly, those between H-9/H3-18, H-9/H3-19, H-15R/H3-18, and
H-11R/H3-18 indicated their mutual cis relationship and the
R-orientation. On the basis of the above results, the relative
configuration of 4, named moluccensin K, was established as shown
in Figure S4.
83.7 CH
51.3 CH3
84.1 CH
52.0 CH3
3.60 s
176.1 qC
39.9 CH
25.7 CH2
177.0 qC
40.1 CH
25.5 CH2
2.57 m
1.35 m
1.61 m
0.89 t, 7.4
1.10 d, 6.8
2.48b
1.32 m
1.74 m
0.94 t, 7.4
1.14 d, 7.2
4′
5′
10.7 CH3
17.4 CH3
11.4 CH3
18.0 CH3
1-Acyl
1′′
175.4 qC
34.5 CH
18.9 CH3
18.3 CH3
176.3 qC
34.9 CH
19.1 CH3
19.1 CH3
2′′
2.68 m
1.18 d, 6.8
1.14 d, 6.8
2.55b
1.21 d, 7.2
1.21 d, 7.2
3′′
4′′
a When detected in acetone-d6, two singlet peaks of H-3 and H-30 are
overlapped. But they are completely separated from that of H-17. When
detected in CDCl3, however, peaks of H-3, H-30, and H-17 are partially
separated from each other. b Overlapped signals assigned by 1H-1H
COSY and HSQC spectra without designating multiplicity.
Compound 5 had the molecular formula C37H48O11, as established
by HR-TOFMS, larger than 4 by a CH2 unit. The NMR data of 5
were similar to those of 4, except for the presence of one more
2S-methylbutyryl group [δH 0.88 (t, J ) 7.5 Hz), 1.14 (d, J ) 7.0
Hz), 1.38, m, 1.60, m, 2.07, m; δC 11.2 CH3, 17.6 CH3, 25.8 CH2,
41.3 CH, 175.7 qC] (Tables 1 and 2) and the absence of an
isobutyryl group (3ꢀ-isobutyryl group in 4). The second 2-meth-
ylbutyryl group in 5 was corroborated by 1H-1H COSY correlations
between H3-4′/H2-3′, H2-3′/H-2′, and H-2′/H3-5′ and HMBC cross-
peaks between H3-4′/C-3′, H3-4′/C-2′, H3-5′/C-2′, H3-5′/C-1′, and
H-2′/C-1′. The HMBC cross-peak from H-3 (5.15, s) of 5 to the
carbonyl carbon of the 2S-methylbutyryl group placed this group
at C-3. Moreover, the significant NOE interaction observed in 5
from H-3 to Hpro-R-29 helped to establish the 3R-H and the
corresponding 3ꢀ-2S-methylbutyryl group. Therefore, moluccensin
L (5) was identified as 3-O-2S-methylbutyryl-3-deisobutyryloxy-
moluccensin K.
phragmalin nucleus), five methylene, 10 methine (three olefinic),
and 12 quaternary carbons (four carbonyls).
The NMR data19 of 6 (Table 3) and its 2D NMR studies (1H-1H
COSY, HSQC, and HMBC) (Figure S5) indicated the presence of
a methoxycarbonyl group (δH 3.60 s; δC 51.3 CH3, 173.4 qC), an
isobutyryl group [δH 2.68 m, 1.18 (d, J ) 6.8 Hz), 1.14 (d, J ) 6.8
Hz); δC 18.9 CH3, 18.3 CH3, 34.5 CH, 175.4 qC], a 2-methylbutyryl
group [δH 0.89 (t, J ) 7.4 Hz), 1.10 (d, J ) 6.8 Hz), 1.35, m, 1.61,
m, 2.57, m; δC 10.7 CH3, 17.4 CH3, 25.7 CH2, 39.9 CH, 176.1
qC], and a ꢀ-furanyl ring (δH 6.53 br s, 7.52 br s, 7.53 br s; δC
110.2 CH, 125.8 qC, 140.9 CH, 142.6 CH).
Two protons of a methylene group [δH 2.43 (d, J ) 12.0 Hz),
2.55a; δC 33.4], showing HMBC correlations to C-5 (δC 36.0) and
C-7 (δC 173.4), were assignable to H2-6, corroborated by their
1H-1H COSY interactions with H-5 (Figure S5). A pair of
geminally coupled protons [δH 2.48 (d, J ) 11.6 Hz), 2.66 (d, J )
11.6 Hz)] of a methylene (δC 38.4), exhibiting HMBC correlations
to C-1, C-2, C-3, and C-4 (Figure S5), were identified as H2-29.
The proton of an oxygenated methine group (δH 5.09 s; δC 72.3),
showing HMBC correlations to C-13, C-18, C-20, C-21, and C-22
Moluccensin M (6) had the molecular formula C35H46O11 (HR-
1
TOFMS), with 13 degrees of unsaturation. From its H and 13C
NMR data (Table 3), it was clear that seven of the 13 elements
came from three carbon-carbon double bonds and four ester
functions. Therefore, the molecule was hexacyclic. DEPT experi-
ments revealed that 6 had eight methyl (a methoxy, a primary
methyl, three secondary methyls, and three tertiary methyls of the

Limonoids from Xylocarpus moluccensis
Journal of Natural Products, 2010, Vol. 73, No. 4 647
(Figure S5), was assigned as H-17, and protons of a tertiary methyl
group (δH 1.25 s; δC 17.1), exhibiting HMBC cross-peaks to C-12,
C-13, C-14, and C-17 (Figure S5), were identified as H3-18.
Moreover, a ∆8,14 double bond was suggested by HMBC interactions
between H3-18/C-14, H-9/C-8, and H-9/C-14. The proton of the
second oxygenated methine group (δH 5.13 s; δC 84.0 in acetone-
d6 and δH 5.06 s; δC 84.9 in CDCl3), showing HMBC correlations
to C-2 and C-4 (Figure S5), was identified as H-3, and that of the
third oxygenated one (δH 5.13 s; δC 83.7 in acetone-d6 and δH 5.04 s;
δC 84.1 in CDCl3), exhibiting HMBC cross-peaks to C-1, C-2, C-8,
and C-14, was identified as H-30.
Table 4. 1H NMR (500 MHz) Data (δ) for Moluccensins N-Q
(7-10) in CDCl3 (J in Hz)
position
1
7
8
9
10
3.52, dd
(6.0, 4.0)
3.53, dd
(6.0, 4.0)
2.01, dd
(5.5, 3.0)
1.99, dd
(5.5, 3.0)
2.26, m
2.01, dd
(5.5, 3.0)
1.99, dd
(5.5, 3.0)
2.24, m
2a
2b
2.88, dd
(14.5, 6.0)
2.55, dd
(14.5, 4.0)
2.90, d (10.0) 2.82, d (10.0) 1.68, m
2.30, m
2.60, dd
2.91, dd
(14.5, 6.0)
2.50, dd
(14.5, 4.0)
2.77, dt
(14.5, 5.5)
2.76, dt
(14.5, 5.5)
1.68, m
2.10, m
2.08, m
5
6a
6b
HMBC correlations between H-3/C-30 and H-30/C-3 confirmed
the linkage of the fragment C1-C2-C30. Protons of the second
tertiary methyl group (δH 1.16 s; δC 17.4), exhibiting HMBC cross-
peaks to C-1, C-5, C-9, and C-10, were identified as H3-19, and
those of the third tertiary methyl group (δH 0.80 s; δC 14.6), showing
HMBC correlations to C-3, C-4, and C-5 (Figure S5), were assigned
to H3-28. Furthermore, the strong HMBC cross-peak from H-3 (5.13
s in acetone-d6 and 5.06 s in CDCl3) to C-1′ (δC 176.1 in acetone-
d6 and 177.0 in CDCl3) of the 2-methylbutyryl group disclosed its
location at C-3. The isobutyryl group, however, was suggested to
be attached to C-1 by its downshifted chemical shift (δC 90.6 in
acetone-d6 and 90.3 in CDCl3) (Table 3), being almost the same as
that of moluccensin A,14 whose structure was confirmed by single-
crystal X-ray diffraction. In addition, the 1H-1H COSY correlation
between H-17/17-OH observed in CDCl3 disclosed the opening of
the ring-D.
2.26, m
2.63, dd
2.10, m
2.08, m
(15.5. 11.0)
(16.5. 10.0)
7
9
5.32, d (3.0) 5.31, d (3.0)
2.23, ma
1.60, m
2.24, ma
1.08, m
2.20, m
2.22, ma
1.67, m
2.22, ma
1.31, m
2.06, m
2.30, ma
1.60, m
1.60, m
1.86, m
1.86, m
2.29, ma
1.60, m
1.60, m
1.85, m
1.85, m
1.60, m
1.50, m
1.25, m
1.28, m
1.73, t (8.5)
0.86, s
11R
11ꢀ
12R
12ꢀ
15R
15ꢀ
16
2.95, d (19.0) 2.90, d (19.0) 1.58, m
2.60, d (19.0) 2.62, d (19.0) 1.50, m
1.30, m
1.30, m
1.73, t (8.5)
0.86, s
1.02, s
2.33, ma
17
18
19
20
21
22
5.61, s/5.60, s 5.62, s
0.95, s
0.92, s
0.93, s
0.95, s
1.02, s
2.29, ma
6.14, br s
6.24, br s
1.08, d (7.0) 1.07, d (7.0)
7.35, br s
6.99, dd
6.96, dd
Though the HMBC correlation from H-30 to the last carbonyl
carbon (δC 175.6, C-15) was not observed due to the small quantity
of 6, a C15-C30 ester linkage, which was suggested by the
downshifted chemical shift of C-30 (δC 83.7)20 (Table 3), and being
in accordance with 13 unsaturation degrees in 6, was further
corroborated by diagnostic fragments at m/z 569.2714 and 509.2554
in the positive HRTOF-MS2 of 6 that originate from the subsequent
loss of a molecule of furan-3-carbaldehyde and methyl formate
(Scheme S1). Moreover, acylation of 6 with propionyl chloride in
pyridine afforded the 2,17-O-dipropionyl derivative of 6. This result
supported the C15-C30 linkage.
(15.0, 9.0)
6.37, d (15.0) 5.79, d (16.0)
(16.0, 9.0)
23
6.23, br s/6.17,
br s
26
27
28
29
30a
30b
1.39, s
1.39, s
1.05, s
1.12, s
1.01, s
1.07, s
1.20, s
5.20, s
1.01, s
1.18, s
5.20, s
1.05, s
1.12, s
1.01, s
4.95, s/4.94, s 4.92, s
7-OMe 3.74, s/3.73, s 3.73, s
a Overlapped signals assigned by 1H-1H COSY, HSQC, and HMBC
spectra without designating multiplicity.
The relative configuration of 6 was established on the basis of
the NOESY interactions. The significant NOE interaction observed
in 6 (Figure S6) from H-3 to Hpro-R-29 helped to establish the 3R-H
and the corresponding 3ꢀ-2-methylbutyryl group. Moreover, NOE
interactions between H-5/H-17, H-11ꢀ/H-17, and H-17/H3-5′
established the ꢀ-orientation of H-5 and H-17. Similarly, those
between H-9/H3-18, H-9/H3-19, H-9/H-30, and H3-19/H-30 indi-
cated their mutual cis relationship and the R-orientation. Thus, the
relative configuration of the 16-norphragmanlin skeleton in 6 was
established as shown in Figure S6. The absolute configuration at
C-2′ in 6 was assumed to be S, the same as that in moluccensins
H-L.
[δH 5.61/5.60 s, 2.95 (d, J ) 19.0 Hz), 2.60 (d, J ) 19.0 Hz); δC
78.04/77.97 CH, 41.9/41/8 qC, 79.65 qC, 33.79/33.75 CH2, 169.4/
169.1 qC] (Tables 4 and 5), was corroborated by HMBC correla-
tions between H2-15/C-14, H2-15/C-16, H-17/C-13, H-17/C-14, and
H-17/C-16 (Figure S7). This suggested that 7 was an andirobin-
type limonoid closely related to methyl angolensate.22 The oxygen
bridge between C-1 and C-14 was confirmed by the HMBC
correlation from H-1 to C-14. Moreover, the ꢀ-orientation of H-1,
suggested to be the same as that of methyl angolensate by its two
proton-proton coupling constants (6.0 and 4.0 Hz) with H2-2,22
was corroborated by the NOE interaction between H-1/H3-19
(Figure S8). The relative configuration was supported by NOE
interactions between H3-19/H-9, H-11R/H-9, H-11R/H3-18, H-15R/
H3-18, H-15ꢀ/H-1, and H-12ꢀ/H-17 (Figure S8). Therefore, the
structure of moluccensin N was identified as 7.
Moluccensin O (8) had a molecular formula the same as that of
7. The NMR data of 8 were similar to those of 7, except for the
presence of a different γ-hydroxybutenolide group substituted at
C-17. The NMR data of the γ-hydroxybutenolide group in 8,
characterized by two broad proton singlets at δH 6.14 (H-21) and
6.24 (H-22) and by resonances at δC 163.7 (C-20), 98.1 (C-21),
121.8 (C-22), and 169.4 (C-23), were found to be the same as those
of kihadanin A.23 Thus, the structure of moluccensin O was
elucidated as 8.
Compound 7 had the molecular formula C27H34O9 with 11
degrees of unsaturation. APT experiments and the HSQC spectrum
revealed that it contained five tertiary methyl (one a methoxy), six
methylene (one olefinic), six methine (one olefinic and three
oxygenated), and 10 quaternary carbons (two olefinic and four
carbonyls). A γ-hydroxybutenolide group at C-17 was characterized
by two broad proton singlets at δH 7.35 (H-22) and 6.23/6.17 (H-
23) and by resonances at δC 133.6/133.5 (C-20), 170.3/170.1 (C-
21), 150.2/149.8 (C-22), and 97.5/97.0 (C-23), the same as that in
febrifugin A.21 The appearance of pairs of most proton and carbon
resonances in the NMR spectra of 7 suggested the presence of C-23
epimers. The presence of a ketone carbonyl (δC 213.3/213.0), two
ester carbonyls (δC 174.0/173.7 and 169.4/169.1), and a double bond
1
(δC 145.3/145.2, 112.0) was also determined from its H and 13C
The molecular formula of compound 9 was established to be
C30H46O3 by HR-ESIMS. APT experiments and the HSQC spectrum
revealed signals for eight methyl (one secondary and seven tertiary),
seven methylene, seven methine (three olefinic), and eight quater-
NMR data. These groups accounted for seven degrees of unsat-
uration, and the remaining four degrees of unsaturation required 7
to be tetracyclic. A δ-lactone ring, characterized by the NMR data

648 Journal of Natural Products, 2010, Vol. 73, No. 4
Wu et al.
Table 5. 13C (125 MHz) NMR Data (δ) for Moluccensins N-Q
(7-10) in CDCl3
In summary, moluccensins H-L are rare phragmalins possessing
a C-30 carbonyl group in conjugation with a ∆8,14 double bond or
∆
8,9, ∆14,15 double bonds, and moluccensin M is a ring-D-opened
position
7
8
9
10
16-norphragmalin with an unprecedented carbon skeleton. Moluc-
censins N-O are andirobin-type limonoids, and moluccensins P-Q
are tirucallane derivatives.
1
2
3
4
5
6
7
8
77.1, CH
77.0, CH
39.3, CH2
213.0, qC
48.0, qC
43.0, CH
32.6, CH2
174.0, qC
144.9, qC
49.6, CH
44.0, qC
23.8, CH2
29.4, CH2
41.9, qC
79.9, qC
38.6, CH2
34.9, CH2
216.8, qC
47.9, qC
51.9, CH
24.4, CH2
38.5, CH2
34.9, CH2
216.8, qC
47.9, qC
51.9, CH
24.4, CH2
39.6/39.5, CH2
213.3/213.0, qC
48.0/47.9, qC
43.0/42.9, CH
33.0/32.9, CH2
174.0/173.7, qC
145.3/145.2, qC
49.6/49.5, CH
44.01/43.98, qC
23.6/23.5, CH2
28.8, CH2
Experimental Section
118.3, CH 118.2, CH
General Experimental Procedures. Optical rotations were recorded
on a Polaptronic HNQW5 automatic high-resolution polarimeter
(Schmidt & Haensch Co. Ltd.). UV spectra were obtained on a Beckman
DU-640 UV spectrophotometer, and MALDITOFMS spectra were
measured on a Bruker APEX II spectrometer in positive ion mode.
NMR spectra were recorded in CDCl3 using a Bruker AV-400 or AV-
500 spectrometer with TMS as the internal standard. Preparative HPLC
was carried out on ODS columns (250 × 20 mm i.d. and 250 × 10
mm i.d., YMC) with a Waters 2998 photodiode array detector. For
CC, silica gel (200-300 mesh) (Qingdao Mar. Chem. Ind. Co. Ltd.)
and RP C18 gel (Cosmosil C18-PREP 140 µm, Nacalai Tesque, Kyoto,
Japan) were used.
Plant Material. The seeds of X. moluccensis were collected in
October 2007 in the mangrove wetlands of Krishna estuary, Andhra
Pradesh, India. The identification of the plant was performed by one
of the authors (T.S.). A voucher sample (No. IndianXM-01) is
maintained in the Herbarium of the South China Sea Institute of
Oceanology.
Extraction and Isolation. The dried seeds (7.0 kg) of X. moluccensis
were extracted three times with 95% EtOH at room temperature. The
extract was concentrated under reduced pressure, followed by suspen-
sion in H2O and extraction with EtOAc. The resulting EtOAc extract
(320 g) was chromatographed on silica gel and eluted using a
CHCl3-MeOH system (100:0-5:1) to yield 230 fractions. Fractions
70 to 80 (19.0 g) were combined and further separated using RP C18
CC (MeCN-H2O, 50:50-100:0) to afford 60 subfractions. Then
subfractions 27 to 37 were combined and further purified by preparative
HPLC (YMC-Pack ODS-5-A, 250 × 20 mm i.d. and 250 × 10 mm
i.d., MeOH-H2O, 50:50 to 55:45) to yield 1 (8.0 mg), 2 (10.0 mg), 3
(4.0 mg), 4 (4.0 mg), 5 (5.2 mg), 6 (2.0 mg), 7 (4.0 mg), 8 (5.0 mg),
9 (4.0 mg), 10 (4.0 mg), and 3ꢀ,22S-dihydroxytirucalla-7,24-dien-23-
one (3.0 mg).
145.4, qC
48.4, CH
35.1, qC
18.2, CH2
33.5, CH2
44.0, qC
145.5, qC
48.4, CH
35.1, qC
18.2, CH2
33.5, CH2
44.0, qC
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
7-OMe
41.9/41.8, qC
79.65, qC
33.79/33.75, CH2 33.5, CH2
51.2, qC
51.1, qC
34.1, CH2
28.1, CH2
52.4, CH
22.1, CH3
12.8, CH3
40.8, CH
18.8, CH3
156.2, CH 157.5, CH
120.1, CH 118.3, CH
202.8, qC
75.2, qC
34.1, CH2
28.1, CH2
52.4, CH
22.1, CH3
12.8, CH3
40.3, CH
18.7, CH3
169.4/169.1, qC
78.04/77.97, CH
13.6/13.5, CH3
21.6, CH3
133.6/133.5, qC
170.3/170.1, qC
150.2/149.8, CH
97.5/97.0, CH
169.0, qC
80.0, CH
14.2, CH3
21.7, CH3
163.7, qC
98.1, CH
121.8, CH
169.4, qC
171.3, qC
26.4, CH3
26.4, CH3
24.5, CH3
21.6, CH3
26.4/26.2, CH3
21.4/21.3, CH3
112.0, CH2
25.8, CH3
21.4, CH3
112.3, CH2 27.4, CH3
52.3, CH3
24.6, CH3
21.6, CH3
27.4, CH3
52.2/52.1, CH3
nary carbons (one olefinic, one oxygenated, and two carbonyl).
These data combined with two olefinic carbons (δC 118.3 CH, 145.4
qC) indicated that 9 was a tirucallane-type triterpene having a ∆7,8
double bond and a C-3 ketone group. Comparison of its NMR data
with those of 23,26-dihydroxytirucalla-7,24-dien-3-one15 revealed
that they had the same tetracyclic core structure. The only difference
between them was the different side chain at C-17. The presence
of the ∆22,23 double bond in the side chain of 9 was corroborated
by a homonuclear proton-proton spin system H3-21-H-20-H-
Absolute Configuration of C-2 in the 2-Methylbutyryl Group of
Moluccensins H-L (1-5). A portion of 1 (2 mg) was dissolved in
EtOH (0.5 mL) and treated with 6% KOH in H2O (1 mL), with stirring
at room temperature for 24 h. The reaction mixture was concentrated
and partitioned between EtOAc and H2O (3:1). After extraction with
EtOAc (×3), the aqueous layer was acidified with HCl to pH 3.0 and
extracted again with CH2Cl2 (×3). The organic solubles were combined,
subjected to Sephadex LH-20 CC (CH2Cl2-MeOH, 1:1), and dried
over anhydrous Na2SO4 to provide a mixture of 1:1 isobutanoic acid
and 2-methylbutyric acid (0.6 mg), which were identified on the basis
of their mass spectra. Since isobutanoic acid is optically inactive, the
absolute configuration at C-2 in 2-methylbutyric acid was suggested
22-H-23 observed in its H-1H COSY spectrum, and that of the
1
C-24 ketone group was confirmed by HMBC correlations between
H-23/C-24, H3-26/C-24, and H3-27/C-24 (Figure S9). The
E-geometry of the ∆22,23 double bond was established by the
coupling constants of H-22 and H-23 (15 Hz). The 25-OH,
suggested by the chemical shift of C-25 at δC 75.2 and the molecular
formula of 9, was confirmed by HMBC correlations between H3-
26/C-25 and H3-27/C-25 (Figure S9). Therefore, the structure of
moluccensin P was identified as 9.
as S by the [R]25 +10 (c 0.06, Me2CO) of the above mixture. In the
D
same way, the absolute configuration of C-2 in the 2-methylbutyryl
The molecular formula of compound 10 was established to be
C27H40O3. The NMR data of 10 were similar to those of 9, except for
the absence of three carbons in the side chain of 9, viz., C-25, C-26,
and C-27. The presence of a terminal C-24 carboxyl group was
suggested by its chemical shift at δC 171.3 qC and was supported by
group of moluccensins I-L (2-5) was indicated to be S.
Moluccensin H (1): white, amorphous powder; [R]25 +137.8 (c
D
1
0.27, Me2CO); UV (MeCN) λmax 210.3, 284.4 nm; H and 13C NMR
data, see Tables 1 and 2; HR-TOFMS m/z 675.2770 [calcd for
C36H44O11Na [M + Na]+, 675.2776], m/z 691.2573 [calcd for
C36H44O11K [M + K]+, 691.2515].
the molecular formula of 10. Connection of the E-double bond (∆22,23
)
Moluccensin I (2): white, amorphous powder; [R]25D +119.0 (c 0.42,
to the carboxyl group in the side chain of 10 was established by HMBC
correlations between H-22/C-24 and H-23/C-24. Thus, the structure
of moluccensin Q was elucidated as 10.
1
Me2CO); UV (MeCN) λmax 206.2, 285.6 nm; H and 13C NMR data,
see Tables 1 and 2; HR-TOFMS m/z 675.2780 [calcd for C36H44O11Na
[M + Na]+, 675.2776], HR-TOFMS m/z 653.2969 [calcd for C36H45O11
[M + H]+, 653.2956].
The insecticidal activity of compounds 1-5 was tested using a
conventional leaf disk method against the fifth instar larvae of
Brontispa longissima (Gestro). Moluccensins H (1) and I (2) showed
moderate insecticidal activity at a concentration of 100 mg/L,
whereas other compounds showed no activity. The lethal rates of
moluccensin H (1) at exposure times of 72 and 96 h were 20.7%
and 27.6%, respectively, while those of moluccensin I (2) were
10.7% and 28.7%, respectively.
Moluccensin J (3): white, amorphous powder; [R]25D +74.5 (c 0.11,
1
Me2CO); UV (MeCN) λmax 206.1, 282.0 nm; H and 13C NMR data,
see Tables 1 and 2; HR-TOFMS m/z 675.2785 [calcd for C36H44O11Na
[M + Na]+, 675.2776], m/z 653.2979 [calcd for C36H45O11 [M + H]+,
653.2956].
Moluccensin K (4): white, amorphous powder; [R]25D +30.7 (c 0.14,
1
Me2CO); UV (MeCN) λmax 206.5, 257.1 nm; H and 13C NMR data,

Limonoids from Xylocarpus moluccensis
Journal of Natural Products, 2010, Vol. 73, No. 4 649
see Tables 1 and 2; HR-TOFMS m/z 677.2943 [calcd for C36H46O11Na
[M + Na]+, 677.2932], m/z 655.3126 [calcd for C36H47O11 [M + H]+,
655.3113].
NMR spectra of 6. This material is available free of charge via the
Internet at http://pubs.acs.org.
Moluccensin L (5): white, amorphous powder; [R]25D +2.9 (c 1.13,
References and Notes
1
Me2CO); UV (MeCN) λmax 210.9, 253.5 nm; H and 13C NMR data,
(1) Ekong, D. E. U.; Olagbemi, E. O. Tetrahedron Lett. 1967, 8, 3525–
3527.
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K]+, 707.2828].
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Moluccensin M (6): white, amorphous powder; [R]25D +1.4 (c 0.2,
acetone); UV (MeCN) λmax 216.8 nm; 1H and 13C NMR data, see Table
3; HR-TOFMS m/z 665.2925 [calcd for C35H46O11Na [M + Na]+,
665.2932], m/z 681.2679 [calcd for C35H46O11K [M + K]+, 681.2672].
Moluccensin N (7): white, amorphous powder; [R]25D -16.2 (c 0.05,
acetone); UV (MeCN) λmax 214.0 nm; 1H and 13C NMR data, see Tables
4 and 5; HR-ESIMS m/z 525.2065 [calcd for C27H34O9Na [M + Na]+,
525.2095]; HR-ESIMS m/z 541.1804 [calcd for C27H34O9K [M + K]+,
541.1834].
Moluccensin O (8): white, amorphous powder; [R]25D -35.0 (c 0.04,
acetone); UV (MeCN) λmax 214.0 nm; 1H and 13C NMR data, see Tables
4 and 5; HR-ESIMS m/z 525.2076 [calcd for C27H34O9Na [M + Na]+,
525.2095]; HR-ESIMS m/z 541.1817 [calcd for C27H34O9K [M + K]+,
541.1834].
Moluccensin P (9): white, amorphous powder; [R]25D -56.2 (c 0.04,
acetone); UV (MeCN) λmax 190.0 nm; 1H and 13C NMR data, see Tables
4 and 5; HR-ESIMS m/z 489.3149 [calcd for C30H46O3Cl [M + Cl]-,
489.3141].
Moluccensin Q (10): white, amorphous powder; [R]25D 69.0 (c 0.05,
acetone); UV (MeCN) λmax 192.0 nm; 1H and 13C NMR data, see Tables
4 and 5; HR-ESIMS m/z 447.2666 [calcd for C27H40O3Cl [M + Cl]-,
447.2672].
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Acknowledgment. Financial support for this work from the Impor-
tant Project of Chinese Academy of Sciences (KSCX2-YW-R-093,
KZCX2-YW-216), the National High Technology Research and
Development Program of China (863 Program) (2007AA09Z407), the
National Natural Science Foundation of China (20772135), and the
Research Foundation for Young Talents from the South China Sea
Institute of Oceanology, Chinese Academy of Sciences (M.-Y.L.,
SQ200802) is gratefully acknowledged. We are grateful to Mr. T.
Srikanth (Acharya Nagarjuna University, Guntur, Andhra Pradesh,
India) for his assistance in the collection and identification of the seeds
of X. moluccensis. We are also thankful to Mr. M. Srinivas for his
assistance in collection of the seeds.
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(19) NMR data detected in acetone-d6 are used in the main text except
when stated otherwise.
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Supporting Information Available: Figures S1-S9 and Scheme
S1; copies of HR-MS (HR-TOFMS or HR-ESIMS), 1H and 13C NMR
spectra of compounds 1-5 and 7-10; copies of RP-HPLC preparative
chromatogram, ESI-MS, HRTOF-MS, HRTOF-MS-MS, 1D and 2D
(23) Garcez, F. R.; Garcez, W. S.; Roque, N. F.; Castellano, E. E.;
Zukerman-Schpector, J. Phytochemistry 2000, 55, 733–740.
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