Synthesis of new α-glucosidase inhibitors based on oleanolic acid incorporating cinnamic amides

Article abstract of DOI:10.1248/cpb.59.1051

A series of α-glucosidase inhibitors with the oleanolic acid core and different cinnamic amide ligands were designed and synthesized. Their preliminary structure-activity relationships were analyzed. In general, the compounds with 3,28-disubstituted olean

Full text of DOI:10.1248/cpb.59.1051

August 2011
Note
Chem. Pharm. Bull. 59(8) 1051—1056 (2011)
1051
a
Synthesis of New -Glucosidase Inhibitors Based on Oleanolic Acid
Incorporating Cinnamic Amides
Wei NIE,a Jian-Guang LUO,a Xiao-Bing WANG,a Hong YIN,a Hong-Bin SUN,b He-Quan YAO,b and
Ling-Yi KONG*,a
a Department of Natural Medicinal Chemistry, China Pharmaceutical University; and b Department of Medicinal
Chemistry, China Pharmaceutical University; 24 Tongjia Xiang, Nanjing 210009, People’s Republic of China.
Received March 24, 2011; accepted May 24, 2011; published online May 30, 2011
A series of a-glucosidase inhibitors with the oleanolic acid core and different cinnamic amide ligands were
designed and synthesized. Their preliminary structure–activity relationships were analyzed. In general, the com-
pounds with 3,28-disubstituted oleanolic acid exhibited stronger activity than those 28-monosubstituted ana-
logues, and variation of cinnamic amide substitution significantly affected a-glucosidase inhibition activities.
Most of the compounds showed potent inhibitory activity against a-glucosidase with much greater efficacy than
a typical a-glucosidase inhibitor, acarbose.
Key words synthesis; a-glucosidase inhibitor; oleanolic acid; cinnamic amide
Type II diabetes mellitus affects approximately 215 million
people worldwide. It is currently clear that aggressive control
of hyperglycemia in patients with type II diabetes can attenu-
ate the development of chronic complications such as
retinopathy and nephropathy.1) To date, therapy for type II di-
abetes relies mainly on several approaches intended to sup-
press the hyperglycemia, which include reducing gut glucose
absorption. Therefore inhibition of a-glucosidase, an enzyme
catalyzing the cleavage of glycosidic bonds in oligo-
saccharides or glycoconjugates, is a choice to control elevated
glucose level in blood.
Oleanolic acid is the hypoglycemic component in many
Traditional Chinese Medicines (TCMs). In previous reports,
some oleanolic acid derivatives have been designed, synthe-
sized based on inhibitor of glycogen phosphorylase (GP).2—6)
But it was found that oleanolic acid and its derivates were
used to suppress the hyperglycemia for not only inhibitor of
glycogen phosphorylase but also inhibitors of a-glucosidase
in our previous research.7,8) Furthermore, recent investiga-
tions have reported that the compounds with cinnamic amide
unit have strong a-glucosidase inhibition activities.9—11)
These motivated us to carry out further structural modifica-
tions on oleanolic acid by incorporating different cinnamic
amide units.
In the present paper, a series of analogues with the oleano-
lic acid core and different cinnamic amide ligands were
Fig. 1. Structures of Oleanolic Acid Derivatives
designed, synthesized, and evaluated as a-glucosidase in-
hibitors (Fig. 1, Table 1). Their structure–activity relation-
ships also were analyzed.
Table 1. Inhibitory Activity on a-Glucosidase by Oleanolic Acid Deriva-
tives
Compounds
IC50 (mM)
Compounds
IC50 (mM)
Results and Discussion
With oleanolic acid as a lead compound, we sought to
identify a series of oleanolic acid derivatives as novel a-glu-
cosidase inhibitor. Synthetic efforts were focused on struc-
tural modifications at C-3 and C-28 positions. The synthetic
route of 28-substituted oleanolic acid derivatives is outlined
in Chart 1. Piperazine fragment was induced in order to
link cinnamic amide unit with oleanolic acid at C-28.
Oleanolic acid unit and cinnamic amide unit were con-
nected at N-1 and N-4 positions of piperazine, respectively.
On basis of these, 3,28-disubstituted oleanolic acid deriva-
5a
5b
6a
6b
7a
7b
8a
8b
9a
92.6ꢀ2.0
96.5ꢀ2.1
149.7ꢀ3.4
165.5ꢀ4.3
130.0ꢀ2.8
173.4ꢀ4.6
78.9ꢀ1.8
80.0ꢀ1.7
80.8ꢀ1.5
108.3ꢀ3.1
128.0ꢀ3.6
10b
11a
11b
17
18
19
20
21
22
165.2ꢀ4.4
35.5ꢀ0.8
141.8ꢀ4.8
5.9ꢀ0.3
19.7ꢀ0.9
7.9ꢀ0.4
1.9ꢀ0.2
3.9ꢀ0.6
5.9ꢀ0.9
98.5ꢀ1.2
388.0ꢀ9.6
9b
10a
Oleanolic acid
Acarbose
∗ To whom correspondence should be addressed. e-mail: cpu_lykong@126.com
© 2011 Pharmaceutical Society of Japan

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Vol. 59, No. 8
Chart 2. Attempts to Synthesize 3,28-Disubstituted Oleanolic Acid Deriv-
atives
Chart 1. Attempts to Synthesize 28-Substituted Oleanolic Acid Deriva- approximately 50 and 200 fold than oleanolic acid (IC50ꢁ
tives
98.5 mM) and arcarbose (IC50ꢁ388.0 mM)), respectively.
tives were further designed and synthesized, and the syn- Conclusion
thetic route is outlined in Chart 2. In the reduction reaction,
In conclusion, we discovered a series of novel, potent a-
there were two products with different configuration. One glucosidase inhibitors derived from oleanolic acid incorpo-
was a configuration, and the other was b configuration. 3b- rating various cinnamic amide units. Among them, com-
Cinnamamidoolean acid derivatives were many more than pound 20 (IC50ꢁ1.9 mM) possessed the strongest a-glucosi-
3a-cinnamamidoolean acid derivatives because of their dase inhibitory activity, with 200-fold greater efficacy than a
stereospecific blockade. But due to long reaction route, typical a-glucosidase inhibitor, acarbose. These a-glucosi-
3b,28-disubtituted oleanolic acid derivatives were obtained dase inhibitors should be useful lead compounds for the de-
merely. 3a,28-Disubtituted oleanolic acid derivatives were velopment of medicaments to treat diabetic and/or obese pa-
not obtained because of their low yield.
tients. Further investigation of the structure–activity relation-
Biological Activity The synthesized oleanolic acid de- ships and development of superior a-glucosidase inhibitors
rivatives, together with oleanolic acid and acarbose (as posi- are in progress.
tive controls) were biologically evaluated for their inhibitory
activities against a-glucosidase. As showed in Table 1, al-
Experimental
Chemistry NMR spectra were recorded on a Bruker ACF-500 NMR in-
strument (1H: 500 MHz, 13C: 125 MHz) and chemical shifts are reported as
ppm from an internal standard tetramethylsilane (TMS). IR spectra were ob-
tained on a Brucker Tensor 27 spectrophotometer. Mass spectra were ob-
tained on a MS Agilent 1100 Series LC/MSD ion-trap mass spectrometer
[electrospray ionization mass spectrum (ESI-MS)]. Elemental analysis (EA)
was carried out on a Perkin-Elmer 2400 C, H, N analyzer. All commercially
available solvents and reagents were used without further purification. The
starting oleanolic acid with 98% purity was purchased from Nanjing Zelang
Medical Technology Co., Ltd. (Nanjing, China).
most all of the newly synthesized compounds exhibited
stronger inhibitory activity against a-glucosidase than acar-
bose (IC50ꢁ388.0 mM). Interestingly, different substituted
groups on benzene ring of cinnamic amide units were obvi-
ous effect on activity. For instance, F atom could reduce ac-
tivity (17 vs. 18, 5a vs. 6a, 5b vs. 6b), and enlargement of
hydrophobic surface could also reinforce a-glucosidase in-
hibitory activity (7a vs. 9a, 7b vs. 9b, 19 vs. 21).
(3-Acetoxyolean-12-en-28-yl)(piperazin-1-yl)methanone (4) 3-Ace-
toxyolean-12-en-28-oic acid (100 mg) was dissolved in diethyl ether (2 ml)
and oxalyl chloride (0.1 ml) was added dropwise slowly, and the solution
was stirred at room temperature for 4 h. The solvent was removed under re-
duced pressure using a rotary evaporator. The residue was 3-acetoxyolean-
12-en-28-carbonyl chloride (3). Piperazine (40 mg), triethylamine (0.5 ml)
and 4-dimethylaminopyridine (DMAP) (20 mg) were dissolved in CH2Cl2
(5 ml), then the CH2Cl2 solution of 3 was added to mixture and stirred at
room temperature for 5 h. The solvent was removed under reduced pressure
using a rotary evaporator. The residue was washed with water, and evapo-
rated to dryness. The residue was purified by column chromatography on sil-
ica gel to give 4 as a white solid (80 mg, 70.4%). 1H-NMR (500 MHz,
DMSO-d6) d: 0.66 (3H, s), 0.81 (6H, s), 0.88 (9H, s), 1.04 (3H, s) (7ꢂCH3),
2.95 (1H, br d, Jꢁ10.8 Hz, H-18), 4.40 (1H, br d, Jꢁ10.8 Hz, H-3), 5.08
However, compared with oleanolic acid (IC50ꢁ98.5 mM),
incorporation of the cinnamic amides at C-28 didn’t result in
apparent enhancement of the a-glucosidase inhibitory activ-
ity (5a—11b). In this series, the activities of 3-OH deriva-
tives are stronger than 3-OAc derivatives. It may be con-
cluded that the structure size of the hydroxyl was moderate
for the size of cavity bonded with enzyme. While 3,28-disub-
stituted oleanolic acid derivatives (17—22) dramatically en-
hance the a-glucosidase inhibitory activity than oleanolic
acid. Among them, compound 20 showed potent a-glucosi-
dase inhibitory activity with an IC50 value of 1.90 mM, being

August 2011
1053
(1H, br s, H-12), 2.00 (3H, s, 3-OAc), 3.51 (4H, m, piperazine-H-2, 6), 2.73
(4H, m, piperazine-H-3, 5); ESI-MS: 567 [MꢃH]ꢃ.
(1H, d, Jꢁ15.3 Hz, H-8ꢄ), 7.50 (1H, d, Jꢁ15. Hz, H-7ꢄ), 7.79 (2H, m, H-2ꢄ,
6ꢄ), 7.25 (2H, m, H-3ꢄ, 5ꢄ); 13C-NMR (125 MHz, DMSO-d6), d: 174.0 (C-
28), 165.1 (C-7ꢄ), 162.3 (C-4ꢄ), 145.2 (C-13), 140.9 (C-5ꢄ), 132.3 (C-1ꢄ),
130.7 (C-2ꢄ), 121.3 (C-12), 118.6 (C-6ꢄ), 116.2 (C-3ꢄ), 77.3 (C-3), 55.3 (C-
5), 47.7 (C-9ꢄ), 47.3 (C-17), 47.2 (C-8ꢄ), 46.4 (C-19), 45.4 (C-9), 43.5 (C-
14), 41.9 (C-18), 39.2 (C-8), 38.8 (C-1), 38.6 (C-4), 37.1 (C-10), 33.9 (C-
21), 33.3 (C-29), 32.9 (C-7), 30.5 (C-22), 29.6 (C-20), 28.7 (C-23), 28.6 (C-
15), 27.9 (C-30), 27.4 (C-2), 26.2 (C-27), 24.3 (C-16), 23.4 (C-11), 18.4 (C-
6), 16.9 (C-26), 16.5 (C-24), 15.6 (C-25); IR (cmꢅ1): 3451, 2944, 2865,
1649, 1225, 1003, 827; ESI-MS: 673 [MꢃH]ꢃ; Anal. (%) Calcd for
C43H61FN2O3: C 76.75, H 9.14, N 4.16. Found: C 76.59, H 9.12, N 4.15.
(3-Acetoxyolean-12-en-28-yl)[4-(4ꢀ-methoxy)cinnamamidopiperazin-
1-yl]methanone (7b) Following the procedure described for preparation
of 5b, compound 7b was prepared from 4 and 4-methoxylcinnamic acid as
white solid (102.4 mg, 80.0%). 1H-NMR (500 MHz, DMSO-d6) d: 0.66 (3H,
s), 0.80 (6H, s), 0.88 (9H, s), 1.10 (3H, s) (7ꢂCH3), 2.97 (1H, d, Jꢁ12.0 Hz,
H-18), 4.38 (1H, dd, Jꢁ10.8 Hz, H-3), 5.10 (1H, br s, H-12), 2.00 (3H, s, 3-
OAc), 3.40—3.70 (8H, m, piperazine-H), 7.09 (1H, d, Jꢁ15.3 Hz, H-8ꢄ),
7.46 (1H, d, Jꢁ15.3 Hz, H-7ꢄ), 7.66 (2H, d, Jꢁ8.7 Hz, H-2ꢄ, 6ꢄ), 6.96 (2H, d,
Jꢁ8.7 Hz, H-3ꢄ, 5ꢄ), 3.79 (3H, s, OCH3); 13C-NMR (125 MHz, DMSO-d6),
d: 174.7 (C-28), 170.6 (C-10ꢄ), 165.4 (C-7ꢄ), 160.9 (C-4ꢄ), 145.2 (C-13),
142.0 (C-5ꢄ), 130.1 (C-2ꢄ), 128.2 (C-1ꢄ), 121.2 (C-12), 115.9 (C-6ꢄ), 114.7
(C-3ꢄ), 80.4 (C-3), 55.8 (–OCH3), 55.1 (C-5), 47.4 (C-9ꢄ), 47.2 (C-17), 47.2
(C-8ꢄ), 46.4 (C-19), 45.2 (C-9), 43.5 (C-14), 41.9 (C-18), 39.2 (C-8), 38.0
(C-4), 37.7 (C-1), 37.0 (C-10), 33.9 (C-21), 33.3 (C-29), 32.7 (C-7), 30.5
(C-22), 29.6 (C-20), 28.2 (C-23), 28.0 (C-15), 27.8 (C-2), 26.1 (C-27), 24.3
(C-16), 23.6 (C-30), 23.3 (C-11), 21.4 (C-11ꢄ), 18.2 (C-6), 17.1 (C-26), 16.9
(C-24), 15.6 (C-25); IR (cmꢅ1): 3450, 2947, 1734, 1650, 1605, 1515, 1247,
1175; ESI-MS: 727 [MꢃH]ꢃ; Anal. (%) Calcd for C46H66N2O5, C 75.99, H
9.15, N 3.85. Found: C 76.10, H 9.16, N 3.86.
(3-Acetoxyolean-12-en-28-yl)(4-cinnamamidopiperazin-1-yl)metha-
none (5b) Cinnamic acid (60 mg) was dissolved in diethyl ether (2 ml), ox-
alyl chloride (0.4 ml) and DMF (1 d) was added dropwise slowly, and the so-
lution was stirred at room temperature for 2 h. The solvent was removed
under reduced pressure using a rotary evaporator. The residue was cin-
namoyl chloride.
4 (100 mg), triethylamine (0.5 ml) and DMAP (20 mg) were dissolved in
CH2Cl2 (5 ml), then the CH2Cl2 solution of cinnamoyl chloride was added to
mixture and stirred at room temperature for 5 h. The solvent was removed
under reduced pressure using a rotary evaporator. The residue was washed
with water, and evaporated to dryness.
The residue was purified by column chromatography on silica gel to give
5b as white solids (102 mg, 82.9%). 1H-NMR (500 MHz, DMSO-d6), d:
0.66 (3H, s), 0.80 (6H, s), 0.88 (9H, s), 1.10 (3H, s) (7ꢂCH3), 2.98 (1H,
br d, Jꢁ12.3 Hz, H-18), 4.38 (1H, dd, Jꢁ10.8, 3.9 Hz, H-3), 5.10 (1H, br s,
H-12), 2.00 (3H, s, 3-OAc), 3.48—3.80 (8H, m, piperazine-H), 7.24 (1H, d,
Jꢁ15.3 Hz, H-8ꢄ), 7.50 (1H, d, Jꢁ15.3 Hz, H-7ꢄ), 7.71 (2H, m, H-2ꢄ, 6ꢄ),
7.40 (3H, m, H-3ꢄ, 4ꢄ, 5ꢄ); 13C-NMR (125 MHz, DMSO-d6) d: 174.7 (C-28),
170.6 (C-10ꢄ), 165.2 (C-7ꢄ), 145.2 (C-13), 142.1 (C-5ꢄ), 135.6 (C-1ꢄ), 130.1
(C-4ꢄ), 129.2 (C-2ꢄ), 128.5 (C-3ꢄ), 121.2 (C-12), 118.6 (C-6ꢄ), 80.4 (C-3),
55.1 (C-5), 47.4 (C-9ꢄ), 47.2 (C-8ꢄ), 46.4 (C-19), 45.5 (C-9), 43.6 (C-17),
42.2 (C-14), 41.9 (C-18), 39.2 (C-8), 38.0 (C-4), 37.7 (C-1), 37.0 (C-10),
33.9 (C-21), 33.3 (C-29), 32.7 (C-7), 30.5 (C-22), 29.6 (C-20), 28.2 (C-15),
28.2 (C-23), 27.9 (C-2), 26.1 (C-27), 24.3 (C-16), 23.7 (C-30), 23.3 (C-11),
21.4 (C-11ꢄ), 18.2 (C-6), 17.1 (C-26), 16.9 (C-24), 15.6 (C-25); IR (cmꢅ1):
3457, 2946, 1732, 1649, 1618, 1247, 1005, 763; ESI-MS: 697 [MꢃH]ꢃ;
Anal. (%) Calcd for C45H64N2O4: C 77.54, H 9.26, N 4.02. Found: C 77.85,
H 9.29, N 4.03.
(3-Hydroxyolean-12-en-28-yl)(4-cinnamamidopiperazin-1-yl)metha-
none (5a) To a solution of 5b (50 mg) in CH3OH/THF (4 : 3, 3 ml) was
added 4 N NaOH (0.5 ml). The reaction mixture was allowed to stir at room
temperature for 24 h, and the solution was acidified with 10% HCl and fil-
tered. The residue was washed with water, and vacuum dried to give 5a as a
white solid (46.5 mg, 99%). 1H-NMR (500 MHz, DMSO-d6) d: 0.65 (3H, s),
0.66 (3H, s), 0.84 (3H, s), 0.88 (9H, s), 1.11 (3H, s) (7ꢂCH3), 2.98 (1H, d,
Jꢁ11.7 Hz, H-18), 4.28 (1H, dd, Jꢁ10.8, 3.9 Hz, H-3), 5.10 (1H, br s, H-
12), 3.48—3.80 (8H, m, piperazine-H), 7.24 (1H, d, Jꢁ15.6 Hz, H-8ꢄ), 7.50
(1H, d, Jꢁ15.6 Hz, H-7ꢄ), 7.72 (2H, m, H-2ꢄ, 6ꢄ), 7.41 (3H, m, H-3ꢄ, 4ꢄ and
5ꢄ); 13C-NMR (125 MHz, DMSO-d6) d: 174.7 (C-28), 165.2 (C-7ꢄ), 145.1
(C-13), 142.1 (C-5ꢄ), 135.6 (C-1ꢄ), 130.0 (C-4ꢄ), 129.2 (C-2ꢄ), 128.5 (C-3ꢄ),
121.3 (C-12), 118.6 (C-6ꢄ), 77.3 (C-3), 55.4 (C-5), 47.7 (C-9ꢄ), 47.2 (C-17),
47.2 (C-8ꢄ), 46.4 (C-19), 45.5 (C-9), 43.5 (C-14), 41.9 (C-18), 39.2 (C-8),
38.8 (C-1), 38.5 (C-4), 37.1 (C-10), 33.8 (C-21), 33.3 (C-29), 32.9 (C-7),
30.5 (C-22), 29.6 (C-20), 28.7 (C-23), 27.8 (C-2), 27.4 (C-15), 26.2 (C-27),
25.6 (C-30), 24.4 (C-16), 23.4 (C-11), 18.4 (C-6), 17.0 (C-26), 16.5 (C-24),
15.6 (C-25); IR (cmꢅ1): 3435, 2943, 1646, 1619, 1202, 1003, 764; ESI-MS:
655 [MꢃH]ꢃ; Anal. (%) Calcd for C43H62N2O3: C 78.85, H 9.54, N 4.28.
Found: C 79.16, H 9.57, N 4.29.
(3-Acetoxyolean-12-en-28-yl)[4-(4ꢀ-fluoro)cinnamamidopiperazin-1-
yl]methanone (6b) Following the procedure described for preparation of
5b, compound 6b was prepared from 4 and 4-fluorocinnamic acid as white
solid 6b (107.2 mg, 84.9%). 1H-NMR (500 MHz, DMSO-d6) d: 0.66 (3H, s),
0.80 (6H, s), 0.88 (9H, s), 1.11 (3H, s) (7ꢂCH3), 2.97 (1H, d, Jꢁ11.7 Hz, H-
18), 4.38 (1H, dd, Jꢁ10.8, 3.9 Hz, H-3), 5.10 (1H, br s, H-12), 2.00 (3H, s,
3-OAc), 3.40—3.80 (8H, m, piperazine-H), 7.16 (1H, d, Jꢁ15.6 Hz, H-8ꢄ),
7.50 (1H, d, Jꢁ15.6 Hz, H-7ꢄ), 7.76 (2H, m, H-2ꢄ, 6ꢄ), 7.25 (2H, m, H-3ꢄ,
5ꢄ); 13C-NMR (125 MHz, DMSO-d6) d: 174.7 (C-28), 170.6 (C-10ꢄ), 165.1
(C-7ꢄ), 163.3 (C-4ꢄ), 145.2 (C-13), 140.8 (C-5ꢄ), 132.2 (C-1ꢄ), 130.7 (C-2ꢄ),
121.2 (C-12), 118.5 (C-6ꢄ), 116.1 (C-3ꢄ), 80.4 (C-3), 55.1 (C-5), 47.4 (C-9ꢄ),
47.3 (C-17), 47.2 (C-8ꢄ), 46.4 (C-19), 45.4 (C-9), 43.6 (C-14), 41.9 (C-18),
39.2 (C-8), 38.0 (C-4), 37.7 (C-1), 37.0 (C-10), 33.9 (C-21), 33.3 (C-29),
32.7 (C-7), 30.5 (C-22), 29.7 (C-20), 28.2 (C-15), 28.2 (C-23), 27.9 (C-2),
26.1 (C-27), 24.4 (C-16), 23.7 (C-30), 23.3 (C-11), 21.4 (C-11ꢄ), 18.2 (C-6),
17.0 (C-26), 16.9 (C-24), 15.6 (C-25); IR (cmꢅ1): 3450, 2947, 1733, 1650,
1247, 1006, 827; ESI-MS: 715 [MꢃH]ꢃ; Anal. (%) Calcd for C45H63FN2O4:
C 75.59, H 8.88, N 3.92. Found: C 75.36, H 8.85, N 3.90.
(3-Hydroxyolean-12-en-28-yl)[4-(4ꢀ-methoxy)cinnamamidopiperazin-
1-yl]methanone (7a) Following the procedure described for preparation of
5a, compound 7a was prepared from 7b as white solid (42.4 mg, 90.2%).
1H-NMR (500 MHz, DMSO-d6) d: 0.65 (3H, s), 0.66 (3H, s), 0.84 (3H, s),
0.88 (9H, s), 1.09 (3H, s) (7ꢂCH3), 2.97 (1H, d, Jꢁ9.3 Hz, H-18), 4.28 (1H,
dd, Jꢁ5.1 Hz, H-3), 5.10 (1H, br s, H-12), 3.40—3.80 (8H, m, piperazine-
H), 7.09 (1H, d, Jꢁ15.3 Hz, H-8ꢄ), 7.46 (1H, d, Jꢁ15.3 Hz, H-7ꢄ), 7.66 (2H,
d, Jꢁ8.7 Hz, H-2ꢄ, 6ꢄ), 6.96 (2H, d, Jꢁ8.7 Hz, H-3ꢄ, 5ꢄ), 3.79 (3H, s, OCH3);
13C-NMR (125 MHz, DMSO-d6), d: 174.7 (C-28), 165.4 (C-7ꢄ), 160.9 (C-
4ꢄ), 145.2 (C-13), 142.0 (C-5ꢄ), 130.1 (C-2ꢄ), 128.2 (C-1ꢄ), 121.3 (C-12),
115.9 (C-6ꢄ), 114.7 (C-3ꢄ), 77.3 (C-3), 55.7 (-OCH3), 55.4 (C-5), 47.7 (C-
9ꢄ), 47.2 (C-17), 47.2 (C-8ꢄ), 46.4 (C-19), 45.4 (C-9), 43.6 (C-14), 41.9 (C-
18), 39.2 (C-8), 38.8 (C-1), 38.6 (C-4), 37.1 (C-10), 33.9 (C-21), 33.3 (C-
29), 32.9 (C-7), 30.5 (C-22), 29.6 (C-20), 28.7 (C-15), 28.7 (C-23), 27.9 (C-
30), 27.4 (C-2), 26.0 (C-27), 24.3 (C-16), 23.4 (C-11), 18.4 (C-6), 17.0 (C-
26), 16.4 (C-24), 15.6 (C-25); IR (cmꢅ1): 3442, 2941, 1644, 1604, 1513,
1254, 1173; ESI-MS: 685 [MꢃH]ꢃ; Anal. (%) Calcd for C44H64N2O4, C
77.15, H 9.42, N 4.09. Found: C 76.92, H 9.40, N 4.08.
(3-Acetoxyolean-12-en-28-yl)[4-(2ꢀ,3ꢀ-dichloro)cinnamamidopiper-
azin-1-yl]methanone (8b) Following the procedure described for prepara-
tion of 5b, compound 8b was prepared from 4 and 2,3-dichlorocinnamic
1
acid as white solid (116.1 mg, 86.0%). H-NMR (500 MHz, DMSO-d6) d:
0.64 (3H, s), 0.79 (6H, s), 0.87 (9H, s), 1.09 (3H, s) (7ꢂCH3), 2.97 (1H, d,
Jꢁ11.4 Hz, H-18), 4.37 (1H, dd, Jꢁ10.8, 4.5 Hz, H-3), 5.09 (1H, br s, H-
12), 1.99 (3H, s, 3-OAc), 3.40—3.80 (8H, m, piperazine-H), 7.33 (1H, d,
Jꢁ15.3 Hz, H-8ꢄ), 7.82 (1H, d, Jꢁ15.3 Hz, H-7ꢄ), 7.98 (1H, dd, Jꢁ7.8,
1.2 Hz, H-4ꢄ), 7.42 (1H, t, Jꢁ7.8 Hz, H-5ꢄ), 7.67 (1H, dd, Jꢁ7.8, 1.2 Hz, H-
6ꢄ); 13C-NMR (125 MHz, DMSO-d6) d: 174.8 (C-28), 170.6 (C-12ꢄ), 164.5
(C-9ꢄ), 145.2 (C-13), 137.0 (C-7ꢄ), 135.9 (C-1ꢄ), 132.9 (C-3ꢄ), 131.6 (C-2ꢄ),
131.6 (C-4ꢄ), 128.8 (C-5ꢄ), 127.3 (C-6ꢄ), 123.2 (C-8ꢄ), 121.2 (C-12), 80.4
(C-3), 55.1 (C-5), 47.4 (C-11ꢄ), 47.2 (C-17), 47.2 (C-10ꢄ), 46.4 (C-19), 45.5
(C-9), 43.6 (C-14), 41.9 (C-18), 39.2 (C-8), 38.0 (C-4), 37.7 (C-1), 37.0 (C-
10), 33.9 (C-21), 33.3 (C-29), 32.7 (C-7), 30.5 (C-22), 29.6 (C-20), 28.2 (C-
15), 28.2 (C-23), 27.9 (C-2), 26.2 (C-27), 24.3 (C-16), 23.7 (C-30), 23.3 (C-
11), 21.4 (C-13ꢄ), 18.2 (C-6), 17.1 (C-26), 16.9 (C-24), 15.6 (C-25); IR
(cmꢅ1): 3443, 2946, 1731, 1648, 1248; ESI-MS: 765 [MꢃH]ꢃ; Anal. (%)
Calcd for C45H62Cl2N2O4: C 70.57, H 8.16, N 3.66. Found: C 70.85, H 8.19,
N 3.67.
(3-Hydroxyolean-12-en-28-yl)[4-(4ꢀ-fluoro)cinnamamidopiperazin-1-
yl]methanone (6a) Following the procedure described for preparation of
5a, compound 6a was prepared from 6b as white solid 6a (45.3 mg, 95.7%).
1H-NMR (500 MHz, DMSO-d6) d: 0.65 (3H, s), 0.66 (3H, s), 0.84 (3H, s),
0.88 (9H, s), 1.09 (3H, s) (7ꢂCH3), 2.97 (1H, d, Jꢁ9 Hz, H-18), 4.29 (t, 1H,
Jꢁ4.8 Hz, H-3), 5.10 (br s, H-12), 3.50—3.70 (m, 8H, piperazine-H), 7.21
(3-Hydroxyolean-12-en-28-yl)[4-(2ꢀ,3ꢀ-dichloro)cinnamamidopiper-
azin-1-yl]methanone (8a) Following the procedure described for prepara-
tion of 5a, compound 8a was prepared from 8b as white solid (43.9 mg,
92.8%). H-NMR (500 MHz, DMSO-d6) d: 0.65 (6H, s), 0.83 (3H, s), 0.88
(9H, s), 1.09 (3H, s) (7ꢂCH3), 2.99 (1H, m, H-18), 4.28 (1H, d, Jꢁ4.5 Hz,
1
H-3), 5.09 (1H, br s, H-12), 3.40—3.80 (8H, m, piperazine-H), 7.33 (1H, d,

1054
Vol. 59, No. 8
dopiperazin-1-yl]methanone (10a) Following the procedure described
for preparation of 5a, compound 10a was prepared from 10b as white solid
(44.4 mg, 94.5%). 1H-NMR (500 MHz, DMSO-d6) d: 0.66 (6H, s), 0.84 (3H,
s), 0.88 (9H, s), 1.09 (3H, s) (7ꢂCH3), 2.98 (1H, d, Jꢁ10.5 Hz, H-18), 4.28
(1H, d, Jꢁ4.8 Hz, H-3), 5.10 (1H, br s, H-12), 3.40—3.80 (8H, m, piper-
azine-H), 7.44 (1H, d, Jꢁ15.3 Hz, H-8ꢄ), 7.57 (1H, d, Jꢁ15.3 Hz, H-7ꢄ),
7.94 (2H, d, Jꢁ8.4 Hz, H-2ꢄ, 6ꢄ), 7.99 (2H, d, Jꢁ8.4 Hz, H-3ꢄ, 5ꢄ), 3.25 (3H,
s, –SO2CH3); 13C-NMR (125 MHz, DMSO-d6) d: 174.7 (C-28), 164.7 (C-
7ꢄ), 145.1 (C-13), 141.5 (C-5ꢄ), 140.5 (C-4ꢄ), 140.0 (C-1ꢄ), 129.1 (C-3ꢄ),
127.8 (C-2ꢄ), 122.3 (C-6ꢄ), 121.3 (C-12), 77.3 (C-3), 55.4 (C-5), 47.7 (C-9ꢄ),
47.2 (C-17), 47.2 (C-8ꢄ), 46.4 (C-19), 45.5 (C-9), 43.9 (–CH3), 43.6 (C-14),
41.9 (C-18), 39.2 (C-8), 38.8 (C-1), 38.6 (C-4), 37.1 (C-10), 33.9 (C-21),
33.3 (C-29), 32.9 (C-7), 30.5 (C-22), 29.7 (C-20), 28.7 (C-15), 28.7 (C-23),
27.9 (C-30), 27.4 (C-2), 26.2 (C-27), 24.3 (C-16), 23.4 (C-11), 18.4 (C-6),
17.0 (C-26), 16.5 (C-24), 15.6 (C-25); IR (cmꢅ1): 3443, 2946, 1647, 1306,
1150; ESI-MS: 733 [MꢃH]ꢃ; Anal. (%) Calcd for C44H64N2O5S, C 72.09, H
8.80, N 3.82, S 4.37. Found: C 72.23, H 8.82, N 3.81, S 4.36.
Jꢁ15.3 Hz, H-8ꢄ), 7.82 (1H, d, Jꢁ15.3 Hz, H-7ꢄ), 7.98 (1H, d, Jꢁ8.1 Hz, H-
4ꢄ), 7.43 (1H, t, Jꢁ7.8 Hz, H-5ꢄ), 7.68 (1H, d, Jꢁ8.1 Hz, H-6ꢄ); 13C-NMR
(125 MHz, DMSO-d6) d: 174.8 (C-28), 164.5 (C-9ꢄ), 145.1 (C-13), 137.0
(C-7ꢄ), 135.9 (C-1ꢄ), 132.9 (C-3ꢄ), 131.6 (C-2ꢄ), 131.6 (C-4ꢄ), 128.8 (C-5ꢄ),
127.3 (C-6ꢄ), 123.2 (C-8ꢄ), 121.3 (C-12), 77.3 (C-3), 55.4 (C-5), 47.7 (C-
11ꢄ), 47.2 (C-17), 47.2 (C-10ꢄ), 46.4 (C-19), 45.4 (C-9), 43.6 (C-14), 41.9
(C-18), 39.2 (C-8), 38.9 (C-1), 38.5 (C-4), 37.1 (C-10), 33.9 (C-21), 33.3
(C-29), 32.9 (C-7), 30.5 (C-22), 29.6 (C-20), 28.7 (C-15), 28.7 (C-23), 27.8
(C-30), 27.4 (C-2), 26.2 (C-27), 24.3 (C-16), 23.4 (C-11), 18.4 (C-6), 16.9
(C-26), 16.5 (C-24), 15.6 (C-25); IR (cmꢅ1): 3451, 2944, 2864, 1647, 1249;
ESI-MS: 723 [MꢃH]ꢃ; Anal. (%) Calcd for C43H60Cl2N2O3, C 71.35, H
8.35, N 3.87. Found: C 71.06, H 8.31, N 3.85.
(3-Acetoxyolean-12-en-28-yl){4-[3ꢀ-(6ꢁ-methoxynaphthalen-2ꢀ-
yl)acrylamido]piperazin-1-yl}methanone (9b) Following the procedure
described for preparation of 5b, compound 9b was prepared from 4 and 3-
(6-methoxynaphthalen-2-yl) acrylic acid as white solid (106.9 mg, 78.0%).
1H-NMR (500 MHz, DMSO-d6) d: 0.67 (3H, s), 0.79 (6H, s), 0.88 (9H, s),
1.10 (3H, s) (7ꢂCH3), 2.98 (1H, d, Jꢁ12.9 Hz, H-18), 4.38 (1H, dd, Jꢁ11.4,
3.6 Hz, H-3), 5.09 (1H, br s, H-12), 1.99 (3H, s, 3-OAc), 3.50—3.80 (8H, m,
piperazine-H), 7.30 (1H, d, Jꢁ15.3 Hz, H-10ꢄ), 7.63 (1H, d, Jꢁ15.3 Hz, H-
9ꢄ), 7.82—7.91 (3H, m, H-3ꢄ, 4ꢄ and 8ꢄ), 7.19 (1H, d, Jꢁ9.0 Hz, H-7ꢄ), 7.35
(1H, s, H-5ꢄ), 8.08 (1H, s, H-1ꢄ), 3.89 (3H, s, 6ꢄ-OCH3); 13C-NMR
(125 MHz, DMSO-d6) d: 174.7 (C-28), 170.6 (C-16ꢄ), 165.3 (C-13ꢄ), 158.6
(C-6ꢄ), 145.2 (C-13), 142.4 (C-11ꢄ), 135.5 (C-8ꢄ), 131.0 (C-1ꢄ), 130.0 (C-
4ꢄ), 129.4 (C-2ꢄ), 128.8 (C-3ꢄ), 127.7 (C-9ꢄ), 125.2 (C-10ꢄ), 121.1 (C-12),
119.6 (C-5ꢄ), 117.6 (C-12ꢄ), 106.7 (C-7ꢄ), 80.4 (C-3), 55.8 (-OCH3), 55.1
(C-5), 47.4 (C-15ꢄ), 47.2 (C-17), 47.2 (C-14ꢄ), 46.4 (C-19), 45.5 (C-9), 43.6
(C-14), 41.9 (C-18), 39.0 (C-8), 38.0 (C-4), 37.7 (C-1), 37.0 (C-10), 33.9
(C-21), 33.3 (C-29), 32.7 (C-7), 30.5 (C-22), 29.6 (C-20), 28.2 (C-15), 28.2
(C-23), 27.9 (C-2), 26.2 (C-27), 24.4 (C-16), 23.6 (C-30), 23.3 (C-11), 21.4
(C-17ꢄ), 18.2 (C-6), 17.1 (C-26), 16.9 (C-24), 15.6 (C-25); IR (cmꢅ1): 3452,
2947, 1734, 1632, 1249, 1030, 849; ESI-MS: 777 [MꢃH]ꢃ; Anal. (%) Calcd
for C50H68N2O5, C 77.28, H 8.82, N 3.60. Found: C 77.04, H 8.79, N 3.58.
(3-Hydroxyolean-12-en-28-yl){4-[3ꢀ-(6ꢁ-methoxynaphthalen-2ꢀ-
yl)acrylamido]piperazin-1-yl}methanone (9a) Following the procedure
described for preparation of 5a, compound 9a was prepared from 9b as
(3-Acetoxyolean-12-en-28-yl)[4-(4ꢀ-nitro)cinnamamidopiperazin-1-
yl]methanone (11b) Following the procedure described for preparation of
5b, compound 11b was prepared from 4 and 4-nitrocinnamic acide as white
1
solid (119.1 mg, 90.9%). H-NMR (500 MHz, DMSO-d6) d: 0.66 (3H, s),
0.80 (6H, s), 0.88 (9H, s), 1.11 (3H, s) (7ꢂCH3), 2.97 (1H, d, Jꢁ14.4 Hz, H-
18), 4.38 (1H, d, Jꢁ10.8 Hz, H-3), 5.10 (1H, br s, H-12), 2.00 (3H, s, 3-
OAc), 3.40—3.80 (8H, m, piperazine-H), 7.48 (1H, d, Jꢁ15.6 Hz, H-8ꢄ),
7.60 (1H, d, Jꢁ15.6 Hz, H-7ꢄ), 8.01 (2H, d, Jꢁ8.7 Hz, H-2ꢄ, 6ꢄ), 8.26 (2H, d,
Jꢁ8.7 Hz, H-3ꢄ, 5ꢄ); 13C-NMR (125 MHz, DMSO-d6) d: 174.2 (C-28),
170.0 (C-10ꢄ), 164.0 (C-7ꢄ), 147.5 (C-4ꢄ), 144.6 (C-13), 141.6 (C-1ꢄ), 138.8
(C-5ꢄ), 128.9 (C-2ꢄ), 123.7 (C-3ꢄ), 122.8 (C-6ꢄ), 120.6 (C-12), 79.8 (C-3),
54.6 (C-5), 46.9 (C-9ꢄ), 46.7 (C-17), 46.7 (C-8ꢄ), 45.9 (C-19), 44.8 (C-9),
42.0 (C-14), 41.4 (C-18), 38.7 (C-8), 37.4 (C-4), 37.1 (C-1), 36.4 (C-10),
33.3 (C-21), 32.7 (C-29), 32.2 (C-7), 29.9 (C-22), 29.1 (C-20), 27.7 (C-15),
27.7 (C-23), 27.3 (C-2), 25.6 (C-27), 23.8 (C-16), 23.1 (C-30), 22.8 (C-11),
20.8 (C-11ꢄ), 17.6 (C-6), 16.5 (C-26), 16.4 (C-24), 15.0 (C-25); IR (cmꢅ1):
3450, 2946, 1732, 1651, 1344, 1247; ESI-MS: 742 [MꢃH]ꢃ; Anal. (%)
Calcd for C45H63N3O6, C 72.84, H 8.56, N 5.66. Found: C 72.55, H 8.54, N
5.67.
1
(3-Hydroxyolean-12-en-28-yl)[4-(4ꢀ-nitro)cinnamamidopiperazin-1-
yl]methanone (11a) Following the procedure described for preparation of
5a, compound 11a was prepared from 11b as white solid (45.3 mg, 96.0%).
1H-NMR (500 MHz, DMSO-d6) d: 0.66 (6H, s), 0.84 (3H, s), 0.88 (9H, s),
1.09 (3H, s) (7ꢂCH3), 2.98 (1H, d, Jꢁ8.4 Hz, H-18), 4.28 (1H, d, Jꢁ5.1 Hz,
H-3), 5.10 (1H, br s, H-12), 3.40—3.80 (8H, m, piperazine-H), 7.48 (1H,d,
Jꢁ15.6 Hz, H-8ꢄ), 7.60 (1H, d, Jꢁ15.6 Hz, H-7ꢄ), 8.01 (2H, d, Jꢁ8.7 Hz, H-
2ꢄ, 6ꢄ), 8.25 (2H, d, Jꢁ8.7 Hz, H-3ꢄ, 5ꢄ); 13C-NMR (125 MHz, DMSO-d6) d:
174.2 (C-28), 164.0 (C-7ꢄ), 147.4 (C-4ꢄ), 144.6 (C-13), 141.6 (C-1ꢄ), 138.9
(C-5ꢄ), 128.9 (C-2ꢄ), 123.8 (C-3ꢄ), 123.3 (C-12), 122.7 (C-6ꢄ), 76.7 (C-3),
54.8 (C-5), 47.1 (C-9ꢄ), 46.6 (C-17), 46.6 (C-8ꢄ), 45.8 (C-19), 45.0 (C-9),
43.0 (C-14), 41.3 (C-18), 38.6 (C-8), 38.2 (C-1), 38.0 (C-4), 36.5 (C-10),
33.3 (C-21), 32.7 (C-29), 32.3 (C-7), 30.0 (C-22), 29.0 (C-20), 28.1 (C-15),
28.1 (C-23), 27.2 (C-2), 26.8 (C-30), 25.6 (C-27), 23.7 (C-16), 22.8 (C-11),
17.8 (C-6), 16.4 (C-26), 15.9 (C-24), 15.0 (C-25); IR (cmꢅ1): 3445, 2944,
1620, 1521, 1344; ESI-MS: 700 [MꢃH]ꢃ; Anal. (%) Calcd for C43H61N3O5,
C 73.78, H 8.78, N 6.00. Found: C 73.92, H 8.76, N 6.01.
white solid (41.4 mg, 88.1%). H-NMR (500 MHz, DMSO-d6) d: 0.65 (6H,
s), 0.83 (3H, s), 0.88 (9H, s), 1.09 (3H, s) (7ꢂCH3), 2.98 (1H, d, Jꢁ10.2 Hz,
H-18), 4.28 (1H, d, Jꢁ4.8 Hz, H-3), 5.10 (1H, br s, H-12), 3.40—3.80 (8H,
m, piperazine-H), 7.30 (1H, d, Jꢁ15. 3 Hz, H-10ꢄ), 7.63 (1H, d, Jꢁ15.3 Hz,
H-9ꢄ), 7.82—7.92 (3H, m, H-3ꢄ, 4ꢄ, 8ꢄ), 7.20 (1H, d, Jꢁ9.0 Hz, H-7ꢄ), 7.35
(1H, s, H-5ꢄ), 8.08 (1H, s, H-1ꢄ), 3.89 (3H, s, 6ꢄ-OCH3); 13C-NMR
(125 MHz, DMSO-d6) d: 174.7 (C-28), 165.3 (C-13ꢄ), 158.6 (C-6ꢄ), 145.1
(C-13), 142.4 (C-11ꢄ), 135.5 (C-8ꢄ), 131.0 (C-1ꢄ), 130.3 (C-4ꢄ), 129.4 (C-
2ꢄ), 128.8 (C-3ꢄ), 127.7 (C-9ꢄ), 125.2 (C-10ꢄ), 121.3 (C-12), 119.6 (C-5ꢄ),
117.6 (C-12ꢄ), 106.7 (C-7ꢄ), 77.3 (C-3), 55.7 (–OCH3), 55.4 (C-5), 47.7 (C-
15ꢄ), 47.2 (C-17), 47.2 (C-14ꢄ), 46.5 (C-19), 45.5 (C-9), 43.6 (C-14), 41.9
(C-18), 39.2 (C-8), 38.8 (C-1), 38.5 (C-4), 37.1 (C-10), 33.9 (C-21), 33.3
(C-29), 32.9 (C-7), 30.5 (C-22), 29.7 (C-20), 28.7 (C-15), 28.7 (C-23), 27.9
(C-2), 27.4 (C-30), 26.2 (C-27), 24.3 (C-16), 23.4 (C-11), 18.4 (C-6), 17.0
(C-26), 16.5 (C-24), 15.6 (C-25); IR (cmꢅ1): 3426, 2942, 2863, 1628, 1260;
ESI-MS: 735 [MꢃH]ꢃ; Anal. (%) Calcd for C48H66N2O4, C 78.43, H 9.05,
N 3.81. Found: C 78.66, H 9.07, N 3.82.
(3-Oxoolean-12-en-28-yl)(piperazin-1-yl)methanone (14) Following
the procedure described for preparation of 4, compound 14 was prepared
from 3-oxoolean-12-en-28-oic acid (12) as white solid 14 (80 mg, 70.4%).
(3-Aminoolean-12-en-28-yl)(piperazin-1-yl)methanone (16) Oxime
14 (1 g) and CH3COONH4 (1.8 g) were dissolved in CH3OH (66 ml) and
stirred at room temperature, and NaBH3CN (1.4 g) was added to the stirred
solution rapidly. Then 15% TiCl3 (2.3 ml) was added dropwise slowly after
the temperature was decreased to 0 °C. The reaction mixture was allowed to
stir at room temperature for 12 h, and the solution was alkalified with 2 N
NaOH to pH 10 and extracted with CH2Cl2. The CH2Cl2 layer was concen-
trated in vacuo to give 16 as a white solid (920 mg, 89%).
(3-Cinnamamidoolean-12-en-28-yl)(4-cinnamamidopiperazin-1-
yl)methanone (17) Following the procedure described for preparation of
5b, compound 17 were prepared from 16 and cinnamic acid as white solid
(109.3 mg, 73.0%). 1H-NMR (500 MHz, DMSO-d6) d: 0.68 (3H, s), 0.77
(3H, s), 0.78 (3H, s), 0.89 (9H, s), 1.13 (3H, s) (7ꢂCH3), 2.99 (1H, br d,
Jꢁ12.0 Hz, H-18), 3.76 (1H, m, H-3), 5.10 (1H, br s, H-12), 3.40—3.80
(8H, m, piperazine-H), 6.76 (1H, d, Jꢁ15.6 Hz, H-8ꢄ), 7.24 (1H, d,
Jꢁ15.3 Hz, H-8ꢆ), 7.50 (1H, d, Jꢁ15.3 Hz, H-7ꢆ), 7.30—7.72 (11H, m, H-
7ꢄ, and Ph-H); 13C-NMR (125 MHz, DMSO-d6) d: 174.1 (C-28), 164.6 (C-
7ꢆ), 164.3 (C-7ꢄ), 144.5 (C-13), 141.4 (C-5ꢄ), 138.1 (C-5ꢄꢄ), 135.0 (C-1ꢄ),
(3-Acetoxyolean-12-en-28-yl)[4-(4ꢀ-methylsulfonyl)cinnamami-
dopiperazin-1-yl]methanone (10b) Following the procedure described
for preparation of 5b, compound 10b was prepared from 4 and 4-methylsul-
1
fonylcinnamic acid as white solid (115.8 mg, 85.8%). H-NMR (500 MHz,
DMSO-d6) d: 0.66 (3H, s), 0.80 (6H, s), 0.88 (9H, s), 1.11 (3H, s) (7ꢂCH3),
2.98 (1H, d, Jꢁ11.1 Hz, H-18), 4.38 (1H, dd, Jꢁ12.0, 4.5 Hz, H-3), 5.10
(1H, br s, H-12), 2.00 (3H, s, 3-OAc), 3.40—3.80 (8H, m, piperazine-H),
7.44 (1H, d, Jꢁ15.3 Hz, H-8ꢄ), 7.57 (1H, d, Jꢁ15.3 Hz, H-7ꢄ), 7.94 (2H, d,
Jꢁ8.4 Hz, H-2ꢄ, 6ꢄ), 7.99 (2H, d, Jꢁ8.4 Hz, H-3ꢄ, 5ꢄ), 3.35 (3H, s,
–SO2CH3); 13C-NMR (125 MHz, DMSO-d6) d: 174.7 (C-28), 170.6 (C-10ꢄ),
164.7 (C-7ꢄ), 145.2 (C-13), 141.5 (C-5ꢄ), 140.5 (C-4ꢄ), 140.0 (C-1ꢄ), 129.1
(C-3ꢄ), 127.8 (C-2ꢄ), 122.3 (C-6ꢄ), 121.2 (C-12), 80.4 (C-3), 55.1 (C-5), 47.4
(C-9ꢄ), 47.2 (C-17), 47.2 (C-8ꢄ), 46.4 (C-19), 45.5 (C-9), 43.9 (–CH3), 43.6
(C-14), 41.9 (C-18), 39.2 (C-8), 38.0 (C-4), 37.7 (C-1), 37.0 (C-10), 33.9
(C-21), 33.3 (C-29), 32.7 (C-7), 30.5 (C-22), 29.6 (C-20), 28.2 (C-15), 28.2
(C-23), 27.9 (C-2), 26.2 (C-27), 24.3 (C-16), 23.6 (C-30), 23.4 (C-11), 21.4
(C-11ꢄ), 18.2 (C-6), 17.1 (C-26), 16.9 (C-24), 15.6 (C-25); IR (cmꢅ1): 3487,
2946, 1732, 1651, 1247, 1150, 827; ESI-MS: 775 [MꢃH]ꢃ; Anal. (%) Calcd
for C46H66N2O6S, C 71.28, H 8.58, N 3.61, S 4.14. Found: C 71.20, H 8.57,
N 3.62, S 4.13.
(3-Hydroxyolean-12-en-28-yl)[4-(4ꢀ-methylsulfonyl)cinnamami-

August 2011
1055
135,0 (C-1ꢆ), 129.4 (C-4ꢄ), 129.0 (C-4ꢆ), 128.7 (C-2ꢆ), 128.6 (C-2ꢄ), 127.8
{3-[3ꢀ-(6ꢁ-Methoxynaphthalen-2ꢀ-yl)acrylamido]olean-12-en-28-yl}{4-
(C-3ꢄ), 127.2 (C-3ꢄꢄ), 127.2 (C-6ꢆ), 122.7 (C-12), 118.1 (C-6ꢄ), 55.8 (C-3), [3ꢀ-(6ꢁ-methoxynaphthalen-2ꢀ-yl)acrylamido]piperazin-1-yl}methanone
55.4 (C-5), 47.0 (C-9ꢄ), 46.6 (C-17), 46.6 (C-8ꢄ), 45.8 (C-19), 44.8 (C-9), (21) Following the procedure described for preparation of 5b, compound
43.0 (C-14), 41.3 (C-18), 38.6 (C-4), 38.6 (C-8), 37.6 (C-1), 36.4 (C-10),
33.3 (C-21), 32.6 (C-29), 32.2 (C-7), 30.0 (C-22), 29.0 (C-20), 28.3 (C-23),
21 were prepared from 16 and 3-(6-methoxynaphthalen-2-yl) acrylic acid as
white solid (106.4 mg, 59.1%). 1H-NMR (500 MHz, DMSO-d6) d: 0.66 (3H,
27.9 (C-15), 27.2 (C-2), 25.5 (C-27), 24.8 (C-16), 23.7 (C-30), 22.7 (C-11), s), 0.77 (3H, s), 0.79 (3H, s), 0.89 (9H, s), 1.13 (3H, s) (7ꢂCH3), 2.99 (1H,
18.0 (C-6), 16.7 (C-26), 16.3 (C-24), 15.0 (C-25); IR (cmꢅ1): 3441, 3360, br d, Jꢁ12.9 Hz, H-18), 3.77 (1H, m, H-3), 5.12 (1H, br s, H-12), 3.40—3.80
2944, 2863, 1648, 1620, 989, 975, 706, 685; ESI-MS: 784 [MꢃH]ꢃ; Anal.
(%) Calcd for C52H69N3O3, C 79.65, H 8.87, N 5.36. Found: C 79.41, H
8.89, N 5.35.
(8H, m, piperazine-H), 6.83 (1H, d, Jꢁ15.6 Hz, H-10ꢄ), 7.51 (1H, d,
Jꢁ15.6 Hz, H-9ꢄ), 7.31 (1H, d, Jꢁ15.3 Hz, H-10ꢆ), 7.64 (1H, d, Jꢁ15.3 Hz,
H-9ꢆ), 7.82—7.91 (6H, m, H-4ꢄ, 8ꢄ, 3ꢄ, 4ꢆ, 8ꢆ, 3ꢆ), 7.20 (2H, dd, Jꢁ2.4,
9.0 Hz, H-7ꢄ, 7ꢆ), 7.68 (1H, s, H-3ꢄ), 7.33 (1H, s, H-5ꢄ), 7.97 (1H, s, H-1ꢄ),
8.08 (1H, s, H-1ꢄ), 3.93, 3.89 (6H, s, –OCH3); 13C-NMR (125 MHz, DMSO-
d6) d: 174.0 (C-28), 164.7 (C-13ꢆ), 164.5 (C-13ꢄ), 158.0 (C-6ꢄ), 157.9 (C-
6ꢆ), 144.6 (C-13), 141.8 (C-11ꢄ), 138.4 (C-11ꢆ), 134.8 (C-8ꢆ), 134.6 (C-8ꢄ),
[3-(4ꢀ-Fluoro)cinnamamidoolean-12-en-28-yl][4-(4ꢀ-fluoro)cin-
namamidopiperazin-1-yl]methanone (18) Following the procedure de-
scribed for preparation of 5b, compound 18 were prepared from 16 and 4-
1
fluorocinnamic acid as white solid (111.2 mg, 71.0%). H-NMR (500 MHz,
DMSO-d6) d: 0.67 (3H, s), 0.77 (3H, s), 0.78 (3H, s), 0.89 (9H, s), 1.13 (3H, 130.3 (C-1ꢄ), 130.3 (C-1ꢆ), 129.7 (C-3ꢄ), 129.7 (C-3ꢆ), 128.8 (C-4ꢄ), 128.8
s) (7ꢂCH3), 2.97 (1H, br d, Jꢁ10.7 Hz, H-18), 3.59 (1H, m, H-3), 5.12 (1H,
br s, H-12), 3.40—3.80 (8H, m, piperazine-H), 6.71 (1H, d, Jꢁ15.6 Hz, H-
8ꢄ), 7.39 (1H,d, Jꢁ15.6 Hz, H-7ꢄ), 7.50 (1H, d, Jꢁ15.3 Hz, H-7ꢆ), 7.18—
7.28, 7.58—7.95 (9H, m, H-8ꢆ, Ph-H); 13C-NMR (125 MHz, DMSO-d6) d:
(C-4ꢆ), 128.3 (C-2ꢆ), 128.2 (C-2ꢄ), 128.1 (C-12ꢆ), 127.2 (C-9ꢄ), 127.1 (C-9ꢆ),
124.7 (C-10ꢆ), 124.0 (C-10ꢄ), 122.0 (C-12), 119.0 (C-5ꢄ), 119.0 (C-5ꢆ),
117.1 (C-12ꢄ), 106.1 (C-7ꢄ), 106.1 (C-7ꢆ), 55.8 (C-3), 55.5 (C-5), 55.2 (6ꢄ-
OCH3), 55.2 (6ꢆ-OCH3), 47.0 (C-15ꢄ), 46.6 (C-17), 46.6 (C-14ꢄ), 45.9 (C-
174.2 (C-28), 164.5 (C-7ꢆ), 164.2 (C-7ꢄ), 162.7 (C-4ꢆ), 162.4 (C-4ꢄ), 144.6 19), 44.8 (C-9), 43.1 (C-14), 41.4 (C-18), 40.2 (C-8), 38.6 (C-4), 37.7 (C-1),
(C-13), 140.3 (C-5ꢄ), 137.0 (C-5ꢆ), 131.7 (C-1ꢄ), 131.6 (C-1ꢆ), 130.1 (C-2ꢆ), 36.5 (C-10), 33.3 (C-21), 32.7 (C-29), 32.2 (C-7), 30.0 (C-22), 29.0 (C-20),
129.5 (C-6ꢆ), 129.4 (C-2ꢄ), 122.6 (C-12), 118.0 (C-6ꢄ), 115.7 (C-3ꢄ), 115.6 28.4 (C-23), 28.1 (C-15), 27.2 (C-2), 25.8 (C-27), 23.8 (C-30), 23.2 (C-16),
(C-3ꢄꢄ), 55.8 (C-3), 55.5 (C-5), 47.0 (C-9ꢄ), 46.6 (C-17), 46.6 (C-8ꢄ), 45.9 22.8 (C-11), 18.1 (C-6), 16.8 (C-26), 16.4 (C-24), 15.0 (C-25); IR (cmꢅ1):
(C-19), 44.8 (C-9), 43.0 (C-14), 41.4 (C-18), 38.6 (C-8), 37.6 (C-1), 36.7 3435, 2941, 1625, 1601, 1390, 1261, 1175, 847; ESI-MS: 944 [MꢃH]ꢃ;
(C-4), 36.5 (C-10), 33.3 (C-21), 32.7 (C-29), 32.2 (C-7), 30.0 (C-22), 29.1 Anal. (%) Calcd for C62H77N3O5, C 78.86, H 8.22, N 4.45. Found: C 78.54,
(C-20), 28.4 (C-23), 28.0 (C-15), 27.2 (C-2), 25.6 (C-27), 24.8 (C-16), 23.8 H 8.20, N 4.44.
(C-30), 23.1 (C-11), 18.1 (C-6), 16.8 (C-26), 16.4 (C-24), 15.0 (C-25); IR
[3-(4ꢀ-Nitro)cinnamamidoolean-12-en-28-yl][4-(4ꢀ-nitro)cinnamami-
(cmꢅ1): 3442, 2945, 2864, 1650, 1626, 1601, 1510, 1226, 980, 828; ESI- dopiperazin-1-yl]methanone (22) Following the procedure described for
MS: 820 [MꢃH]ꢃ; Anal. (%) Calcd for C52H67F2N3O3, C 76.16, H 8.23, N preparation of 5b, compound 22 were prepared from 16 and 4-nitrocinnamic
5.12. Found: C 76.39, H 8.25, N 5.11.
[3-(4ꢀ-Methoxyl)cinnamamidoolean-12-en-28-yl][4-(4ꢀ-methoxyl)cin-
namamidopiperazin-1-yl]mthanone (19) Following the procedure de-
scribed for preparation of 5b, compound 19 were prepared from 16 and 4-
methoxylcinnamic acid as white solid (109.6 mg, 68.0%). 1H-NMR
1
acid as white solid (126.8 mg, 68.0%). H-NMR (500 MHz, DMSO-d6) d:
0.66 (3H, s), 0.77 (3H, s), 0.78 (3H, s), 0.89 (9H, s), 1.13 (3H, s) (7ꢂCH3),
2.99 (1H, br d, Jꢁ10.8 Hz, H-18), 3.74 (1H, m, H-3), 5.12 (1H, br s, H-12),
3.40—3.80 (8H, m, piperazine-H), 6.96 (1H, d, Jꢁ15.6 Hz, H-8ꢄ), 7.51 (1H,
d, Jꢁ15.6 Hz, H-7ꢄ), 7.48 (1H, d, Jꢁ15.3 Hz, H-8ꢆ), 8.24—8.28 (4H, m, H-
(500 MHz, DMSO-d6) d: 0.67 (3H, s), 0.76 (3H, s), 0.78 (3H, s), 0.89 (9H, 3ꢄ, 5ꢄ, 3ꢆ, 5ꢆ), 7.81 (2H, d, Jꢁ8.7 Hz, H-2ꢄ, 6ꢄ), 8.01 (2H, t, Jꢁ8.7 Hz, H-2ꢆ,
s), 1.13 (3H, s) (7ꢂCH3), 2.99 (1H, br d, Jꢁ11.7 Hz, H-18), 3.59 (1H, m, H-
3), 5.12 (1H, br s, H-12), 3.40—3.80 (8H, m, piperazine-H), 6.61 (1H, d,
Jꢁ15.6 Hz, H-8ꢄ), 7.34 (1H, d, Jꢁ15.6 Hz, H-7ꢄ), 7.49 (2H, d, Jꢁ8.7 Hz, H-
6ꢆ); 13C-NMR (125 MHz, DMSO-d6) d: 174.2 (C-28), 164.0 (C-7ꢆ), 163.7
(C-7ꢄ), 147.5 (C-4ꢆ), 147.3 (C-4ꢄ), 144.6 (C-13), 141.7 (C-1ꢄ), 141.6 (C-1ꢆ),
138.9 (C-5ꢄ), 136.0 (C-5ꢆ), 128.9 (C-2ꢄ), 128.3 (C-2ꢆ), 127.0 (C-6ꢆ), 124.0
2ꢄ, 6ꢄ), 6.97 (2H, d, Jꢁ8.7 Hz, H-3ꢄ, 5ꢄ), 6.61 (1H, d, Jꢁ15.6 Hz, H-8ꢆ), 7.34 (C-3ꢆ), 123.8 (C-3ꢄ), 122.7 (C-6ꢄ), 120.6 (C-12), 56.0 (C-3), 55.4 (C-5), 47.0
(1H, d, Jꢁ15.6 Hz, H-7ꢄ), 7.49 (2H, d, Jꢁ8.7 Hz, H-2ꢄ, 6ꢄ), 6.97 (2H, d,
Jꢁ8.7 Hz, H-3ꢄ, 5ꢄ), 3.78, 3.79 (3H, s, –OCH3); 13C-NMR (125 MHz,
DMSO-d6) d: 174.2 (C-28), 164.9 (C-7ꢆ), 164.7 (C-7ꢄ), 160.3 (C-4ꢆ), 160.0
(C-4ꢄ), 144.6 (C-13), 141.4 (C-5ꢄ), 137.9 (C-5ꢆ), 129.5 (C-2ꢄ), 129.4 (C-1ꢄ),
(C-9ꢄ), 46.6 (C-17), 46.6 (C-8ꢄ), 45.9 (C-19), 45.0 (C-9), 41.7 (C-14), 41.4
(C-18), 40.0 (C-8), 38.6 (C-1), 37.7 (C-4), 36.5 (C-10), 33.3 (C-21), 32.7
(C-29), 32.2 (C-7), 30.0 (C-22), 29.1 (C-20), 28.3 (C-23), 28.0 (C-15), 27.2
(C-2), 25.6 (C-27), 24.8 (C-16), 23.8 (C-30), 22.8 (C-11), 18.0 (C-6), 16.7
128.8 (C-1ꢆ), 128.8 (C-2ꢆ), 127.7 (C-6ꢆ), 120.3 (C-12), 115.4 (C-6ꢄ), 114.3 (C-26), 16.4 (C-24), 15.0 (C-25); IR (cmꢅ1): 3431, 2943, 1618, 1520, 1343;
(C-3ꢆ), 114.1 (C-3ꢄ), 55.8 (C-3), 55.6 (C-5), 55.2 (4ꢄ-OCH3), 55.1 (4ꢆ- ESI-MS: 874 [MꢃH]ꢃ; Anal. (%) Calcd for C52H67N5O7, C 71.45, H 7.73,
OCH3), 47.1 (C-9ꢄ), 46.7 (C-17), 46.7 (C-8ꢄ), 46.0 (C-19), 45.0 (C-9), 43.0
(C-14), 41.4 (C-18), 38.8 (C-4), 38.7 (C-8), 37.7 (C-1), 36.5 (C-10), 33.4
(C-21), 32.7 (C-29), 32.3 (C-7), 30.0 (C-22), 29.2 (C-20), 28.4 (C-23), 28.0
(C-15), 27.3 (C-2), 25.6 (C-27), 24.9 (C-16), 23.8 (C-30), 23.2 (C-11), 18.1
N 8.01. Found: C 71.74, H 7.72, N 8.03.
Enzyme Assay The a-glucosidase inhibition assay was performed ac-
cording to the slightly modified method of Pierre et al.12) a-Glucosidase (EC
3.2.1.20) was purchased from Sigma Co. (No. G-5003, Lot. 081k7415). The
(C-6), 16.8 (C-26), 16.4 (C-24), 15.0 (C-25); IR (cmꢅ1): 3442, 2943, 1645, inhibition was measured spectro-photometrically at pH 6.8 and at 37 °C for
1603, 1512, 1254, 1173, 826; ESI-MS: 844 [MꢃH]ꢃ; Anal. (%) Calcd for
C54H73N3O5, C 76.83, H 8.72, N 4.98. Found: C 76.98, H 8.70, N 4.99.
10 min, using 0.01 M p-nitrophenyl a-D-glucopyranoside (PNPG) as a sub-
strate and 1 U/ml of enzyme, in 0.067 M KH2PO4–Na2HPO4 buffer. Oleano-
[3-(2ꢀ,3ꢀ-Dichloro)cinnamamidoolean-12-en-28-yl][4-(2ꢀ,3ꢀ- lic acid was used as positive controls. The increment in absorption at 410 nm
dichloro)cinnamamidopiperazin-1-yl]methanone (20) Following the due to the hydrolysis of PNPG by a-glucosidase was monitored continu-
procedure described for preparation of 5b, compound 20 were prepared ously with an auto multi-functional microplate reader (BIORAD680).
from 16 and 2,3-dichloro cinnamic acid as white solid (108.9 mg, 62.3%).
1H-NMR (500 MHz, DMSO-d6) d: 0.66 (3H, s), 0.77 (3H, s), 0.78 (3H, s),
0.89 (9H, s), 1.12 (3H, s) (7ꢂCH3), 2.98 (1H, br d, Jꢁ10.2 Hz, H-18), 3.76
(1H, m, H-3), 5.11 (1H, br s, H-12), 3.40—3.80 (8H, m, piperazine-H), 6.85
(1H, d, Jꢁ15.6 Hz, H-8ꢄ), 7.71 (1H, d, Jꢁ15.6 Hz, H-7ꢄ), 7.33 (1H, d,
Jꢁ15.3 Hz, H-8ꢆ), 7.82 (1H, d, Jꢁ15.3 Hz, H-7ꢆ), 7.98 (2H, d, Jꢁ7.8 Hz, H-
4ꢄ, 4ꢆ), 7.43 (2H, t, Jꢁ8.1 Hz, H-5ꢄ, 5ꢆ), 7.67 (1H, t, Jꢁ6.3 Hz, H-6ꢄ, 6ꢆ);
Acknowledgments This research work was supported by the National
Natural Science Foundation of China for Outstanding Young Scientists (No.
30525032), the National Natural Science Foundation of China (No.
81073009) and the National Key Scientific and Technological Special Pro-
jects (2009ZX09502-011).
13C-NMR (125 MHz, DMSO-d6) d: 174.1 (C-28), 163.9 (C-9ꢆ), 163.6 (C- References
9ꢄ), 144.6 (C-13), 136.4 (C-7ꢄ), 135.5 (C-1ꢄ), 135.3 (C-1ꢆ), 133.6 (C-3ꢄ),
132.4 (C-4ꢆ), 132.3 (C-7ꢆ), 131.1 (C-4ꢄ), 131.0 (C-3ꢆ), 130.9 (C-2ꢆ), 130.8
(C-2ꢄ), 128.4 (C-8ꢆ), 128.2 (C-5ꢄ), 128.2 (C-5ꢄꢄ), 127.1 (C-6ꢄ), 126.0 (C-8ꢄ),
126.0 (C-6ꢆ), 122.7 (C-12), 56.0 (C-3), 55.4 (C-5), 47.0 (C-11ꢄ), 46.6 (C-
17), 46.6 (C-10ꢄ), 45.8 (C-19), 44.9 (C-9), 43.0 (C-14), 41.3 (C-18), 40.0
(C-8), 38.6 (C-4), 37.8 (C-1), 36.5 (C-10), 33.3 (C-21), 32.7 (C-29), 32.2
(C-7), 30.0 (C-22), 29.1 (C-20), 28.4 (C-23), 28.0 (C-15), 27.3 (C-2), 25.6
(C-27), 24.7 (C-16), 23.8 (C-30), 22.8 (C-11), 18.0 (C-6), 16.7 (C-26), 16.3
(C-24), 15.0 (C-25); IR (cmꢅ1): 3440, 2945, 1650, 1613, 1453, 1409, 1183;
ESI-MS: 920 [MꢃH]ꢃ; Anal. (%) Calcd for C52H65Cl4N3O3, C 67.75, H
7.11, N 4.56. Found: C 67.88, H 7.10, N 4.55.
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