One-pot synthesis of spirooxindole derivatives catalyzed by lipase in the presence of water

Article abstract of DOI:10.1002/adsc.201000523

A facile one-pot synthesis route to spirooxindole derivatives was developed by combining the three types of catalytic activities of lipase from porcine pancreas (PPL) in the presence of water, i.e., the Knoevengel condensation, Michael addition and cyclization. PPL showed excellent catalytic activity and have a good adaptability to different substrates in the reaction. All the reactions go smoothly and provide spirooxindole derivatives with high yield under the mild conditions. This lipase-catalyzed multistep conversion method has provided a new strategy to synthesize spirooxindole derivatives and expanded the application of biocatalysts.

Full text of DOI:10.1002/adsc.201000523

FULL PAPERS
DOI: 10.1002/adsc.201000523
One-Pot Synthesis of Spirooxindole Derivatives Catalyzed by
Lipase in the Presence of Water
a
a
a
a
b
She-Jie Chai, Yi-Feng Lai, Jiang-Cheng Xu, Hui Zheng, Qing Zhu,
a,
and Peng-Fei Zhang *
College of Material, Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou 310036, Peopleꢀs
a
Republic of China
Fax : (+86)-571-2886-2867; e-mail: zpf100@163.com
College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310036, Peopleꢀs
Republic of China
b
Received: July 3, 2010; Revised: December 26, 2010; Published online: February 16, 2011
Supporting information for this article is available on the WWW under
http://dx.doi.org/10.1002/adsc.201000523.
Abstract: A facile one-pot synthesis route to spiroox- under the mild conditions. This lipase-catalyzed mul-
indole derivatives was developed by combining the tistep conversion method has provided a new strat-
three types of catalytic activities of lipase from por- egy to synthesize spirooxindole derivatives and ex-
cine pancreas (PPL) in the presence of water, i.e., panded the application of biocatalysts.
the Knoevengel condensation, Michael addition and
cyclization. PPL showed excellent catalytic activity
and have a good adaptability to different substrates Keywords: enzymatic reactions; lipase catalysis; mul-
in the reaction. All the reactions go smoothly and tistep conversions; one-pot synthesis; spirooxindole
provide spirooxindole derivatives with high yield derivatives
Introduction
oxindole] derivatives in the presence of a chiral phos-
[
8]
phoric acid. Much attention has been forced on en-
Spirooxindoles are commonly occurring heterocyclic vironmentally friendly biosynthesis in this field.
ring systems and are found in many natural products We have been interested in the study of enzymatic
and pharmaceuticals. A range of compounds carry- reactions and especially the enzyme-catalyzed synthe-
[
1]
[
9]
ing the indole system exhibit antibacterial and anti- sis of hetero-yclic compounds recently. Several en-
[2]
fungal activities. The significant biological activity zymes have fully been exhibited great advantages and
and recent synthetic advances of these natural prod- potential in organic transformations such as aldol re-
ucts encouraged the development of biologically action, Michael addition, Diels–Alder reaction, Knoe-
[
10–14]
promising analogues that would be more efficacious venagel reaction, and Mannich reaction.
How-
ever, natural enzymes that are capable of catalyzing
privileged spirooxindole skeletons have high potential multiple reactions are very scarce, and only a few
[
3]
and selective than the original natural products. The
ACHTUNGTRENNUNG
[
4]
for the development of some medicinal agents.
In recent years, numerous efficient transformations ported.
have been developed for the construction of these (PPL)-catalyzed one-pot multiple reaction for synthe-
single-enzyme multistep conversions have been re-
[
15]
Here we report the unprecedented lipase
[
5]
heterocyclic skeletons.
Carreira and co-workers sizing spirooxindole derivatives in the presence of
have developed a reliable methodology to access the water.
pyrrolidinyl-spirooxindole structure starting from
[
6]
imines and spirocyclopropyl oxindoles. Williams ac-
cessed both enantiomers of the target molecule and Results and Discussion
prepared analogues of the natural products in the syn-
[
7]
thesis of spirotryprostatin B. Gong and co-workers In initial research, we tested the reaction of isatin 1a,
described an enantioselective organocatalytic ap- malononitrile 2a, and ethyl acetoacetate 3a as model
proach for the rapid synthesis of spiro[pyrrolidin-3,3’- substrates with various additives in the presence of
Adv. Synth. Catal. 2011, 353, 371 – 375
ꢁ 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
371

She-Jie Chai et al.
FULL PAPERS
Scheme 1. Model reaction.
water. Compounds 1a, 2a, and 3a (0.5 mmol each) after 12 h (entry 1, Table 1) without any additives. In
were added to a solution (0.5 mL water, 3 mL EtOH) contrast, we found that several enzymes displayed ob-
containing 30 mg lipase from porcine pancreas (PPL) servable activities for this reaction, whereby, PPL dis-
at 308C for 3 h. A single product was obtained in played an especially significant role in catalytic activi-
92% isolated yield (Scheme 1), and the results are ty (entries 6, 7, and 11, Table 1). When the reactions
shown in Table 1. were incubated with denatured PPL, or some similar
A series of commercially available hydrolytic en- amino acid, no product was observed (entries 2–5, 10,
zymes have been investigated in order to find the and 12, Table 1). AL-AK showed moderate catalytic
most suitable enzyme for the envisaged one-pot syn- activity for this reaction (entry 11, Table 1). All the
thesis of spirooxindole derivatives (Table 1). It was results suggest that the tertiary structure and the spe-
found that only a trace of product was formed even cific spatial conformation of PPL are responsible for
the one-pot synthesis of spirooxindole derivatives re-
[
a]
action. So PPL was chosen as the catalyst for this re-
action.
Table 1. Optimization of the reaction conditions.
Entry
Catalyst
Amount
mg]
Temp.
[8C]
Time
[h]
Yield
[b]
To optimize the reaction conditions, such as tem-
perature, concentration of catalyst, and reaction time,
some further experiments were performed. The re-
sults are shown in Table 1. It was found that with the
temperature ranging from 208C to 508C, the best
yield of the desired product was obtained at 408C
(entries 11 and 16–18, Table 1). Therefore, 308C is the
most suitable temperature for this reaction. When the
amount of the PPL was increased from 10 mg to
[
[%]
1
2
3
4
5
6
7
8
9
no enzyme
–
30
30
30
30
30
30
30
30
30
30
30
30
30
30
30
20
40
50
30
30
30
12
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
3
1
2
4
trace
trace
trace
trace
trace
82
84
trace
44
trace
92
trace
58
78
94
[c]
CYS
30
30
30
30
30
30
30
30
30
30
30
10
20
40
30
30
30
30
30
30
[
c]
ARG
[
c]
LYS
[
c]
ASN
[c]
AL-M[
c]
AL-A
[
c]
AYL
AL-AK
20 mg, 30 mg, 40 mg, the corresponding yields were
[
c]
[
c]
58% to 78%, 92%, and 94%, respectively (entries 11
and 13–15, Table 1). The outcomes display that 30 mg
PPL is sufficient to push this reaction forward. Larger
amounts of the catalyst did not improve the yields.
Beside, it can be easily seen from the Table 1 that this
reaction was complete after 3 h (entries 11 and 19–21,
Table 1).
The reaction medium has been recognized to be
one of the most important factors influencing the en-
zymatic reaction. We screened the reaction in various
organic solvents in the presence of water and the re-
sults are shown in Table 2. It can be obsserved that
10
11
12
13
14
15
16
17
18
19
20
21
CAL
[
c]
PPL[
d]
PPL
PPL
PPL
PPL
PPL
PPL
PPL
PPL
PPL
PPL
57
91
93
43
81
93
[
a]
Reaction conditions: isatin (0.5 mmol), malononitrile ethanol was the most efficient medium to promote
0.50 mmol), ethyl acetoacetate (0.5 mmol), enzyme,
(
this reaction, and the spirooxindole product was ob-
tained in yield of 92%. Other solvents, such as n-
hexane, CH Cl , CHCl , and acetone did not promote
EtOH (3 mL), water (0.5 mL), 308C.
Isolated yields.
[
[
b]
c]
2
2
3
CYS: cysteine; ARG: arginine; LYS: lysine; ASN: aspar-
agine; AL-M: Amano lipase M from Mucor javanicus;
AL-A: Amano lipase A from Aspergillus niger; AYL:
lipase AY30; AL-AK: Amano lipase AK from Pseudo-
monas fluorescens; CAL: lipase acrylic resin from Candi-
da antarctica; PPL: lipase from porcine pancreas.
PPL predenatured with urea at 1008C for 10 h.
the product formation (entries 1–4 and 9) and other
polar solvents (entries 6–8) led to moderate yields.
The best yield of this reaction was obtained in ethanol
as a solvent, which maybe attribute to the protin
nature of the solvent and that it accelerates the reac-
tion compared to other solvents.
[
d]
372
asc.wiley-vch.de
ꢁ 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Adv. Synth. Catal. 2011, 353, 371 – 375

One-Pot Synthesis of Spirooxindole Derivatives Catalyzed by Lipase in the Presence of Water
Table 2. PPL-catalyzed the reaction of isatin (1a), malononi-
[a]
trile (2a), and ethyl acetoacetate (3a) in different solvents.
[b]
Entry
Solvent
Time [h]
Yield [%]
1
2
3
4
5
6
7
8
9
n-hexane
3
3
3
3
3
3
3
3
3
trace
trace
trace
trace
92
16
23
31
trace
CH Cl
2
2
CHCl3
acetone
ethanol
THF
CH CN
3
DMF
water
[
a]
Reaction conditions: isatin (0.5 mmol), malononitrile
0.5 mmol), ethyl acetoacetate (0.5 mmol), PPL (30 mg),
solvent (3 mL), and water (0.5 mL), shaken at 160 rpm at
08C.
(
3
[
b]
Isolated yields.
In previous studies of enzymatic promiscuity, water
has been considered as an important factor in enzy-
matic activity leading to an acceleration of the
[
16]
enzyme-catalyzed reaction. Therefore, we designed
some experiments to optimize the percentage of
water in water/ethanol binary mixtures for this reac-
tion. The effect of the water concentration on the
considered lipase-catalyzed one-pot synthesis of spi-
rooxindoles reaction is illustrated in Figure 1. As ap-
parent, when the water content was between 10–20%,
we got the desired product with the highest yields of
Figure 2. The structures of the different substrates.
more than 90%. However, once the water content clined sharply due to the insolubility of the substrates.
surpassed 30%, the yield of spirooxindole product de- A 23% yield of spirooxindole product was obtained
when using the pure solvent. All these results indicat-
ed obviously that water was essential in this promiscu-
ous biocatalysis reaction.
With the optimal conditions in hand, we have em-
ployed various different isatins, 1,3-dicarbonyl com-
pounds, and malononitrile or cyanoacetic ester as sub-
strates in order to investigate the generality for the
scope of this new catalystic method (Figure 2). The
results are summarized in Table 3. Gratifyingly, it was
found that nearly all of the corresponding products
were obtained in good yields. However, the reaction
with cyanoacetic ester offered a lower yield than that
with malononitrile, which is probably due to the
lower reactivity of cyanoacetic ester. Although many
substrates and conditions were applied in this reaction
to measure the enantioselectivity, there is no obvious
optical activity and we will undertake related further
research to improve it.
The experiments clearly showed an increased reac-
tion rate when the synthesis of spirooxindole reaction
Figure 1. Influence of water on the PPL-catalyzed one-pot
synthesis of spirooxindoles. Reaction conditions: isatin
was catalyzed by the PPL as compared to other en-
(
(
(
0.5 mmol), malononitrile (0.5 mmol), ethyl acetoacetate
0.5 mmol), PPL (30 mg), ethanol (3 mL), and water
0.5 mL), was shaken at 160 rpm at 308C for 3 h; deionized
[11]
zymes. Based on the mechanism of lipase-catalyzed
carbon-carbon formation which has been widely ac-
water from 0% to 100% [water/ethanol, v/v]; product yield cepted, we propose a tentative mechanism for the
was determined by HPLC.
synthesis of spirooxindole derivative 4 as shown in
Adv. Synth. Catal. 2011, 353, 371 – 375
ꢁ 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
asc.wiley-vch.de
373

She-Jie Chai et al.
FULL PAPERS
Table 3. Synthesis of different spirooxindole derivatives 4 Scheme 2. Firstly, 1a and 2a form 7 quickly by Knoe-
catalyzed by PPL.
venagel condensation, while the 1,3-dicarbonyl com-
pound is pre-activated by the lipase. After the trans-
fer of a proton, intermediate 7 is convered to 8. Sec-
ondly, intermediate 6, which is also pre-activated by
the lipase, is attacked by 8, which leads to a new CÀC
bond formation via Michael addition, and then 10 is
obtained. Thirdly, after enolization and addition to
the cyano group, the intermediate 12 is formed, and
the desired product 4 is obtained via isomerization.
Conclusions
[b]
Entry
Products 4
Yield [%]
mp [8C]
In conclusion, we herein report an unprecedented
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
[a,a,a]
[a,a,b]
[a,a,c]
[a,b,a]
[a,b,b]
[a,b,c]
[b,a,a]
[b,a,b]
[b,a,c]
[b,b,a]
[b,b,b]
[b,b,c]
[c,a,a]
[c,a,b]
[c,a,c]
[c,b,b]
[c,b,c]
[d,a,a]
[d,a,b]
[d,a,c]
92
93
94
87
85
88
93
95
95
85
83
86
93
95
93
88
82
91
94
95
260–262
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
277–278 lipase (PPL)-catalyzed one-pot reaction for the syn-
284–285 thesis of spirooxindole derivatives in the presence of
169–170 water. This reaction can be carried out under mild
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
280–283
269–271
263–265
288–290
conditions and covers a great range of substrates with
excellent yields of spirooxindole products. This novel
protocol provides an efficient, easy to separate, envi-
ronmental friendly synthetic route for synthesis of spi-
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
286–288
rooxindole derivatives, and further extends the appli-
213–215
0
1
2
3
4
5
6
7
8
9
0
cation of enzymes in pharmaceutical industry.
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
270–272
271–272
230–233
282–283
287–289
240–242
246–248
247–249
>300
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
Experimental Section
Materials and General Methods
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
Commercial reagents were used without further purification
unless otherwise indicated. All solvents were distilled prior
to use. Reactions were performed in oven-dried glassware.
Analytical TLC was performed on Merck precoated TLC
ACHTUNGTRENNUNG
A
C
H
T
U
N
G
T
R
E
N
N
U
N
G
>300
[
a]
Reaction conditions: isatins (1 mmol), malononitrile or
cyanoacetic ester (1 mmol), 1,3-dicarbonyl compounds
1 mmol), PPL (30 mg), solvent (5 mL), and water
1 mL), shaken at 160 rpm at 308C.
(
silica gel 60 F254) plates. Melting points were recorded on
an X4-Data microscopic melting point apparatus and are
uncorrected. IR spectra were recorded on a Nicolet 380 FT-
IR spectrophotometer using KBr discs. ESI-MS were ac-
(
(
[
b]
Isolated yields.
Scheme 2. Proposed mechanism.
374
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ꢁ 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Adv. Synth. Catal. 2011, 353, 371 – 375

One-Pot Synthesis of Spirooxindole Derivatives Catalyzed by Lipase in the Presence of Water
1
quired on a Bruker Esquire 3000 plus spectrometer. H and
[5] a) D. Hojo, K. Noguchi, M. Hirano, K. Tanaka, Angew.
13
C NMR spectra were recorded on a Bruker Avance 400
Chem. 2008, 120, 5904–5906; Angew. Chem. Int. Ed.
2008, 47, 5820–5822; b) R. Shintani, S. Y. Hayashi, M.
Murakami, M. Takeda, T. Hayashi, Org. Lett. 2009, 11,
3754–3756.
spectrometer at 400 MHz and 100 MHz in DMSO-d using
6
TMS as internal standard. A C18 column was used in the
HPLC experiments with MeOH/water=85:15 (v/v),
.8 mLmin and UV detection at 254 nm. All the com-
pounds were characterized (IR, H, C NMR and massd
spectroscopy). All enzymes were purchased from Acros,
Alfa, Aldrich and TCI and used directly: Amano lipase M
from Mucor javanicus (EC, 3.1.1.3), Amano lipase A from
Aspergillus niger (EC 3.1.1.3), lipase AY30 (EC 3.1.1.3),
Amano lipase AK from Pseudomonas fluorescens
À1
0
[6] a) C. Meyers, E. M. Carreira, Angew. Chem. 2003, 115,
1
13
7
18–720; b) C. Marti, E. M. Carreira, J. Am. Chem.
Soc. 2005, 127, 11505–11515; c) G. Wuitschik, M.
Rogers-Evans, A. Buckl, M. Bernasconi, M. Marki, T.
Godel, H. Fischer, B. Wagner, I. Parrilla, F. Schuler, J.
Schneider, A. Alker, W. B. Schweizer, K. Muller, E. M.
Carreira, Angew. Chem. 2008, 120, 4588–4591; Angew.
Chem. Int. Ed. 2008, 47, 4512–4515.
(
(
EC 3.1.1.3), lipase acrylic resin from Candida antarctica
EC 3.1.1.3), lipase from porcine pancreas (EC 3.1.1.3).
[
7] a) P. R. Sebahar, R. M. Williams, J. Am. Chem. Soc.
2
000, 122, 5666–5667; b) T. Onishi, P. R. Sebahar,
General Procedure for Synthesis of Spirooxindole
Derivatives
R. M. Williams, Org. Lett. 2003, 5, 3135–3137.
8] X. H. Chen, Q. Wei, S. W. Luo, H. Xiao, L. Z. Gong, J.
Am. Chem. Soc. 2009, 131, 13819–13825.
9] a) S. J. Chai, Y. F. Lai, H. Zheng, P. F. Zhang, Helv.
Chim. Acta 2010, 93, 2231–2236; b) Y. F. Lai, H.
Zheng, S. J. Chai, P. F. Zhang, X. Z. Chen, Green
Chem. 2010, 12, 1917–1918.
[
[
A suspension of isatin 1
anoacetic ester) 2[a-b] (1 mmol), 1,3-dicarbonyl compounds
[a-c] (1 mmol), and 30 mg PPL in 5 mL EtOH in the pres-
ence of water (1 mL) was shaken at 308C and 160 rpm for
h. After completion of the reaction as confirmed by TLC,
ACHTUNGTRENUNNG[ a-d] (1 mmol), malononitrile (or cy-
ACHTUNGTRENNUNG
3ACHTUNGTRENNUNG
3
[
[
10] a) C. Branneby, P. Carlqvist, A. Magnusson, K. Hult, T.
the precipitated product was filtered and washed with water
and cooled EtOH to afford the pure 4.
Brinck, P. Berglund, J. Am. Chem. Soc. 2003, 125, 874–
8
Yu, Green Chem. 2008, 10, 616–618.
75; b) C. Li, X. W. Feng, N. Wang, Y. J. Zhou, X. Q.
11] a) M. Svedendahl, K. Hult, P. Berglund, J. Am. Chem.
Soc. 2005, 127, 17988–17989; b) F. W. Lou, B. K. Liu,
Q. Wu, D. S. Lu, X. F. Lin, Adv. Synth. Catal. 2008, 350,
Acknowledgements
This work was supported by the National Natural Science
Foundation of China (No. 21076052) and National Scie nce
and Technology Ministry of China (No. 2007BAI34B05).
1
959–1962; c) O. Torre, I. Alfonso, V. Gotor, Chem.
Commun. 2004, 1724–1725.
[
12] S. Akai, K. Tanimoto, Y. Kita, Angew. Chem. 2004, 116,
1
431–1434; Angew. Chem. Int. Ed. 2004, 43, 1407–
1
410.
References
[13] X. W. Feng, C. Li, N. Wang, K. Li, W. W. Zhang, Z.
Wang. X. Q. Yu, Green Chem. 2009, 11, 1933–1936.
14] K. Li, T. He, C. Li, X. W. Feng, N. Wang, X. Q. Yu,
Green Chem. 2009, 11, 777–779.
15] a) S. Akai, K. Tanimoto, Y. Kita, Angew. Chem. 2004,
[1] a) C. C. Galliford, K. A. Scheidt, Angew. Chem. 2007,
[
[
1
8
2
19, 8902–8912; Angew. Chem. Int. Ed. 2007, 46, 8748–
758; b) K. Ding, Y. P. Lu, N. Coleska, J. Med. Chem.
006, 49, 3432–3435.
1
1
16, 1431–1434; Angew. Chem. Int. Ed. 2004, 43, 1407–
410; b) S. Akai, T. Naka, S. Omura, K. Tanimoto, M.
[
2] a) J. P. Nandy, M. Prakesch, S. Khadem, P. T. Reddy, U.
Sharma, P. Arya, Chem. Rev. 2009, 109, 1999–2060;
b) M. Pettersson, D. Knueppel, S. F. Martin. Org. Lett.
Imanishi, Y. Takebe, M. Matsugi, Y. Kita, Chem. Eur. J.
002, 8, 4255–4264.
2
2
007, 9, 4623–4626; c) S. Shangary et al., Proc. Natl.
[
16] a) J. Duwensee, S. Wenda, W. Ruth, U. Kragl, Org. Pro-
cess Res. Dev. 2010, 14, 48–57; b) P. Lozano, R. Piam-
tongkam, K. Kohns, T. D. Diego, M. Vaultier, J. L.
Iborra, Green Chem. 2007, 9, 780–784.
Acad. Sci. U.S.A. 2008, 105, 3933–3938.
[
[
3] C. Marti, E. M. Carreira, Eur. J. Org. Chem. 2003,
2
209–2219.
4] C. V. Galliford, J. A. Martenson, C. Stern, K. A.
Scheidt, Chem. Commun. 2007, 631–633.
Adv. Synth. Catal. 2011, 353, 371 – 375
ꢁ 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
asc.wiley-vch.de
375