A nitrilase-mediated entry to 4-carboxymethyl-β-lactams from chemically prepared 4-(cyanomethyl)azetidin-2-ones

Article abstract of DOI:10.1039/c6ra08213k

(3R,4S)-3-Alkoxy/aryloxy-4-(cyanomethyl)azetidin-2-ones were efficiently prepared from readily available 1,2:5,6-di-O-isopropylidene-d-mannitol by means of a classical organic synthesis approach via 4-hydroxymethyl-β-lactams as key intermediates. The corresponding 4-carboxymethyl-β-lactams were subsequently obtained after selective hydrolysis of the nitrile functionality by means of a nitrilase enzyme without affecting the sensitive four-membered ring system, hence overcoming the difficulties associated with the chemical hydrolysis approach. Thus, the implementation of a biocatalytic step allows a convenient synthetic route to new 4-carboxymethyl-β-lactams as versatile building blocks for further elaboration.

Full text of DOI:10.1039/c6ra08213k

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A nitrilase-mediated entry to 4-carboxymethyl-b-
lactams from chemically prepared 4-(cyanomethyl)
azetidin-2-ones†
Cite this: RSC Adv., 2016, 6, 54573
a
a
a
a
a
Lena Decuyper, Nicola Piens, Jens Mincke, Jeroen Bomon, Bert De Schrijver,
a
b
b
a
Karen Mollet, Karel De Winter, Tom Desmet and Matthias D'hooghe*
(
3R,4S)-3-Alkoxy/aryloxy-4-(cyanomethyl)azetidin-2-ones were efficiently prepared from readily available
,2:5,6-di-O-isopropylidene-D-mannitol by means of classical organic synthesis approach via
-hydroxymethyl-b-lactams as key intermediates. The corresponding 4-carboxymethyl-b-lactams were
1
a
4
subsequently obtained after selective hydrolysis of the nitrile functionality by means of a nitrilase enzyme
without affecting the sensitive four-membered ring system, hence overcoming the difficulties associated
with the chemical hydrolysis approach. Thus, the implementation of a biocatalytic step allows
a convenient synthetic route to new 4-carboxymethyl-b-lactams as versatile building blocks for further
elaboration.
Received 30th March 2016
Accepted 23rd May 2016
DOI: 10.1039/c6ra08213k
www.rsc.org/advances
Furthermore, functionalized polyalkoxypiperidines, or simply
iminosugars, can be synthesized starting from 3-alkoxy-4-cya-
Since the accidental discovery of penicillin by A. Fleming in nomethyl-b-lactams. These sugar analogues exhibit inter-
Introduction
18
1
1
928, b-lactam antibiotics belong to one of the most important esting biological properties, such as the selective inhibition of
2
–5
classes of antimicrobial compounds. Apart from their cele- glycosidases and glycoprotein-processing enzymes, which
brated antibacterial activities and other medical applications, makes them convenient for the treatment of diabetes, cancer
6,7
19–22
e.g. in the treatment of malaria, cancer and HIV, b-lactams are and viral infections, including HIV.
also considered to be very interesting building blocks for
A second class of b-lactams attracting a lot of attention in
further transformations due to their strained ring structure both a chemical as well as a biological setting concerns the
containing a reactive amide bond, a concept known as the carboxyl-containing b-lactams, which are considered to be
8
–11
‘
b-lactam synthon method’.
be deployed in the synthesis of a broad range of new nitrogen agents and other biologically active compounds.
compounds with potential bioactivity, which has become example, 4-(1-carboxyethyl)-b-lactams, the synthesis of which
In this way, these scaffolds can valuable building blocks for the preparation of antimicrobial
23–29
For
30,31
a major incentive for the research and development of several has been performed by multiple methods to date,
are
1
2–14
new classes of b-lactams.
One of those classes, the family of 4-(cyanomethyl)azetidin-2- antibiotics.
important intermediates in the preparation of carbapenem
32,33
1-Benzyloxy-4-(2-carboxyethyl)azetidin-2-one on
ones, contains important synthons for the controlled synthesis the other hand, has been reported to act as an intermediate in
of a variety of new compounds including functionalized g-lac- the synthesis of carbacephems, a class of broad-spectrum
34,35
tams, succinimide derivatives and diamino-b-lactams in opti- antibiotics, closely related to the cephalosporins.
Further-
cally pure form, all being promising compounds in terms of more, optically pure (R)-1-benzyloxy-4-(2-carboxyethyl)azetidin-
15
medicinal and synthetic applications. Besides, the synthesis of 2-one can be used as a precursor for the synthesis of (1S,6R)-
multiple antibiotics, with the carbapenem antibiotic thiena- 2-oxa-7-azabicyclo[4.2.0]octane-3,8-dione, a 3,4-fused bicyclic
mycine as one of the most prominent examples, can be dedi- b-lactam, which has been employed as precursor in the
1
6,17
cated to the use of 4-(cyanomethyl)azetidin-2-one substrates.
synthetic route toward new b-lactam antibiotics or b-lactamase
inhibitors. Besides their use for further synthetic trans-
formations, some carboxyl-containing azetidin-2-ones are also
36
a
SynBioC Research Group, Department of Sustainable Organic Chemistry and characterized by their intrinsic biological activities. This struc-
Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653,
tural moiety can for example be found in macrocyclic b-lactam-
B-9000 Ghent, Belgium. E-mail: matthias.dhooghe@UGent.be
b
37,38
fused enediynes.
Natural enediyne antibiotics are prodrugs,
Department of Biochemical and Microbial Technology, Faculty of Bioscience
endowed with potent cytotoxic and anticancer activities, due to
their capability of cleaving single- and double-stranded
Engineering, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
†
Electronic supplementary information (ESI) available. See DOI:
0.1039/c6ra08213k
37–39
DNA.
Moreover, the di- and tri-organotin carboxylates
1
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3
derived from silyl-protected 4-(1-carboxyethyl)-3-(1-hydroxyethyl) compounds 6a–c ranged between 5.0 and 5.5 Hz (CDCl ), indi-
40
44,46
azetidin-2-one are known for their in vitro antitumor activity.
cating a cis-relationship according to literature values.
Next,
In the framework of the biological relevance of both classes b-lactams 6a–c were easily converted into the corresponding
of compounds, as well as our synthetic interest in their 4-hydroxymethyl-b-lactam key intermediates 7a–c in 82–96%
straightforward development, optically pure 4-carboxymethyl-b- yield via a three-step approach, including (i) p-toluenesulphonic
lactams are prepared via hydrolysis of the corresponding nitrile acid-mediated hydrolysis in a THF/water mixture (1/1) under
42,44,45,47
derivatives in this work. The latter are small scaffolds, consist- reux conditions for 4–6 hours,
(ii) subsequent oxidation
ing of a cyclic amide with a high ring tension in combination using sodium periodate in the presence of sodium bicarbonate
with a reactive cyano group, turning these compounds into and stirring in dichloromethane for 2–16 hours at room
43–45,47
attractive synthons from an organic synthesis point of view. The temperature,
and (iii) selective reduction by means of two
two main objectives of this work thus comprise (i) the design of molar equiv. of sodium borohydride in methanol under reux
44,45
an efficient synthetic route toward 4-cyanomethyl-b-lactams for 1–2 hours.
and (ii) their straightforward conversion into the corresponding In the following steps, modications in the hydroxymethyl
-carboxymethyl-b-lactams without affecting the sensitive four- side chain attached to the 4-position of novel b-lactams 7a–c
4
membered ring system.
were performed in order to install the nitrile functionality. At
rst, the hydroxyl group was converted into a better leaving

group in order to create a more reactive compound, sensitive to
nucleophilic substitution reactions (Scheme 2). Two options
were thus explored. For the introduction of a mesyloxy group,
b-lactams 7a,b were treated with 1.5 equiv. of mesyl chloride
Results and discussion
In a rst section, the selective synthesis of cis-4-(cyanomethyl)
azetidin-2-ones 11a–c was performed. In that respect, (E)-N-
and 4 equiv. of triethylamine, providing mesylated b-lactams
[
(2,2-dimethyl-1,3-dioxolan-4-yl)methylidene]amines 4a,b were
prepared in 88–90% yield via condensation of primary amines
a,b with (R)-glyceraldehyde acetonide 2, obtained via
periodate-induced oxidative cleavage of commercially available
48
8
a,b in high yields. In an analogous manner, stirring of
4-hydroxymethyl-b-lactams 7a–c in the presence of tosyl chlo-
3
ride, triethylamine and DMAP under reux conditions for
nearly two days, afforded 4-tosyloxymethyl-b-lactams 9a–c in
1,2:5,6-di-O-isopropylidene-D-mannitol 1 in a quantitative way
60–67% yield. The expected nal step in this synthetic pathway
4
1,42
according to a literature procedure (Scheme 1).
The obtained
consisted of the nucleophilic substitution of both sulfonyloxy
leaving groups by a cyanide anion to give rise to 4-cyanomethyl-
b-lactams 11a–c. However, aer a thorough optimization study,
including variation of the number of equiv. of potassium
cyanide, the solvent, the temperature (incl. microwave condi-
tions), the reaction time., no substitution of either the mesy-
loxy or the tosyloxy group by cyanide could be achieved.
imines 4a,b were subsequently used as substrates in the Stau-
dinger synthesis of (3R,4S)-3-alkoxy/aryloxy-4-(2,2-dimethyl-1,3-
dioxolan-4-yl)-b-lactams 6a–c by using 1.3 equiv. of methoxy–,
benzyloxy– or phenoxyacetyl chloride 5a–c in the presence of an
42–45
excess of triethylamine as a base.
The optically pure b-lac-
tams 6a–c were prepared in 85–89% yield and with high dia-
stereomeric ratios of (90/10)–(95/5), favoring the expected
relative cis-conguration as conrmed by the H NMR (CDCl
spectra. Indeed, the vicinal coupling constants between the
Therefore, inspired by similar cases concerning 4-
1
3
)
49–51
(mesyloxymethyl)azetidin-2-ones described in the literature,
an alternative approach was studied consisting of the
protons on the 3- and 4-position of the b-lactam rings in
Scheme 1
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Scheme 2
preliminary conversion toward more reactive 4-iodomethyl-b- corresponding amides has been reported a few times, both in
52–54
49,56,57
49,58
lactams 10a–c as versatile intermediates,
as iodide is a chemical
and in an enzymatic way,
reports describing
considered to be a very good leaving group combined with the the conversion of the latter nitriles toward carboxylic acids are
expected decrease in steric hindrance during the substitution rather scarce. In one of these examples, 4-(cyanomethyl)
51
reactions as compared to sulfonyloxy leaving groups. Both 4- azetidin-2-one was chemically converted to the corresponding
mesyloxymethyl- and 4-tosyloxymethyl-b-lactams 8a,b and 9a–c methyl ester rst, aer which alkaline hydrolysis gave rise to the
55
were therefore converted into the corresponding iodides 10a–c acid. Similarly, a two-step chemical hydrolysis of silyl-
by means of an excess of sodium iodide in acetone under reux protected 4-cyano-3-(1-hydroxyethyl)azetidin-2-one via the
57
(
69–97%). Eventually, the premised new (3R,4S)-3-alkoxy/ary- intermediate amide has been studied. Otherwise, enzymatic
loxy-4-cyanomethyl-b-lactams 11a–c could be obtained selec- hydrolysis of nitriles is typically performed via two different
tively in 51–62% yield aer treatment with 2.5 equiv. of sodium pathways, leading to either amides or carboxylic acids,
51
cyanide in DMF. It must be mentioned that the KCN-mediated depending on the application of nitrile hydratases or nitrilases
59–62
direct displacement of 3-non-substituted 4-(tosyloxymethyl) (nitrilhydrolases), respectively.
If necessary, the amides
azetidin-2-ones has been performed only once before, using formed by nitrile hydratases can be further hydrolyzed toward
59–62
18-crown-6 as an additive, whereas sulfonyloxy displacements the acids using amidase enzymes.
Only two reports,
by cyanide in 3-substituted b-lactams have not been reported however, describe the biocatalytic conversion of b-lactam-
55
49,58
so far.
containing nitriles.
In these studies, catalyzed by Rhodo-
In the next stage, the selective hydrolysis of the nitrile coccus erythropolis AJ270 cells containing nitrile hydratases and
function within the synthesized (3R,4S)-3-alkoxy/aryloxy-4-cya- amidases, the rst set of enantiomers of racemic 3-non-
nomethyl-b-lactams 11a–c was studied. Whereas the hydrolysis substituted 4-cyano- and 4-cyanomethyl-b-lactams was con-
of nitriles containing
a
b-lactam moiety toward the verted toward the amides, while the others were fully hydrolyzed
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toward the carboxylic acids, which can be attributed to the high
As the bottleneck of this reaction, i.e. the instability of the
enantioselectivity exhibited by the amidases, in contrast to the reactive four-membered ring under the above-mentioned
63
lack of this stereocontrol in the case of nitrile hydratases. In conditions, required more mild – but still effective – proce-
neither of these studies, however, the carboxylic acids were dures, we reverted to biocatalytic protocols for the hydrolysis of
isolated. Instead, the corresponding methyl esters were formed nitriles to carboxylic acids using isolated nitrilase enzymes as
by means of diazomethane immediately aer the biocatalytic the hydrolyzing tools, as already applied successfully in
64,65
transformations. In other words, the selective and one-step previous work.
The repertoire of classical organic synthesis
hydrolysis of nitriles containing a b-lactam moiety toward the can indeed be signicantly enriched by including biochemical
corresponding carboxylic acids, representing valuable building methods, and the interface between organic chemistry and
blocks in organic and medicinal chemistry, has not been biocatalysis is offering new strategies and perspectives as valu-
described in the literature before and thus remains a challenge able alternatives. This can be attributed to the enantio–, stereo–
to be addressed.
and regioselective, efficient and environmentally friendly
The chemical hydrolysis of 4-cyanomethyl-b-lactams 11a–c catalysis applied by enzymes under mild reaction conditions,
was explored rst (Scheme 3). To that end, (3R,4S)-1-butyl-4- which ts perfectly in the framework of the integration of bio-
cyanomethyl-3-phenoxyazetidin-2-one 11c as a representative catalysis into the organic chemistry sector as an answer to the
66,67
example was dissolved in water, aer which HCl and HOAc were increasing demand for sustainable processes.
added (Method A). Unfortunately, no traces of the correspond-
ing carboxylic acid 12c could be observed aer multiple in
To that end, 4-oxoazetidin-2-yl nitriles 11a–c were dissolved
mixture of methanol and K PO –dithiothreitol–
a
a
3
4
attempts, as either no reaction occurred at low temperatures, or ethylenediaminetetra-acetic acid-based buffer (5/95), aer
reux conditions gave rise to complex mixtures resulting from which various nitrilases were added. The resulting reaction
ꢀ
decomposition of the reactants. Subsequently, KOH-induced mixtures were incubated at 30 C and 200 rpm (Scheme 4). Aer
alkaline hydrolysis was studied applying various reaction an extensive cluster screening, investigating 30 different nitri-
68
conditions (Method B), though leading to the same conclu- lases at a small reaction scale using various solvents and
sions. These observations point to the precarious combination enzyme and substrate concentrations, nitrilase-P1-121 seemed
of a cyano group and a sensitive four-membered azaheterocycle, to be the only enzyme catalyzing the conversion of 4-cyano-
making a classical one-step acid- or base-catalyzed nitrile methyl-b-lactams 11a–c quantitatively toward novel (3R,4S)-3-
hydrolysis critical.
alkoxy/aryloxy-4-carboxymethyl-b-lactams 12a–c, as conrmed
Scheme 3
Scheme 4
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Table 1 Conversion, yields and purification efficiencies of the hydrolysis of 4-cyanomethyl-b-lactams 11a–c toward 4-carboxymethyl-b-lac-
tams 12a–c
Conversion aer 4 weeks of
incubation (%)
Yield Method
A (%)
Purication
efficiency (%)
Yield
Method B (%)
Purication
efficiency (%)
1
2
a
b
c
Compound
R
R
11a
11b
11c
iPr
iPr
nBu
Me
Bn
Ph
60
93
70
16
—
12
27
—
17
43
74
—
72
80
—
a
b
Conversion rate determined via LC-MS analysis. Method A: removal of inactivated enzymes and buffer salts, followed by preparative HPLC of the
c
crude reaction mixture. Method B: removal of inactivated enzymes and buffer salts, followed by NaCl-mediated extraction, acidication of the
aqueous phase and another extraction with ethyl acetate.
1
by H NMR, IR and MS analysis. However, these reactions pro- covalent interactions, the catalytic cysteine thiol group
ceeded very slowly, probably due to the rigid structure of nitriles (“Enz-SH”) is capable of forming a covalent bond with the nitrile
11 which might impede an optimal positioning into the cata- functional group in substrates 11, thus giving rise to thio-
lytic center of the enzyme. For this reason, relatively high imidates 13. Water then hydrolyzes these intermediates toward
À1
enzyme concentrations (up till 4 mg mL ) were used when thioesters 15, which are nally converted to the corresponding
scaling up these reactions, with the nitrilase added gradually to carboxylic acids 12 with concomitant expulsion of ammonia,
the reaction mixture during the course of the weeks. The latter aer which the enzymes are released in their active form to
59
approach yielded reasonably constant reaction rates, leading to enter a subsequent catalytic cycle.
varying conversions of the substrates (60% for 11a, 93% for 11b
and 70% for 11c aer 4 weeks, as determined via LC-MS anal-
ysis). It should however be mentioned that, when performing all
Conclusion
reactions at a higher enzyme concentration and a longer incu- In this work, chiral cis-3-alkoxy/aryloxy-4-(2,2-dimethyl-1,3-
bation time, complete conversion of the substrate should be dioxolan-4-yl)-b-lactams were employed successfully for the
achievable, as was observed at a smaller reaction scale. In our synthesis of cis-4-cyanomethyl-b-lactams in nine consecutive
case, however, we opted to make a compromise between reaction steps via 4-hydroxymethyl-b-lactams as key intermedi-
acceptable substrate conversions and a time-efficient reaction ates, starting from the commercially available and enantio-
protocol. Since no side products were formed during the merically pure 1,2:5,6-di-O-isopropylidene-D-mannitol. Next, the
hydrolysis, the conversion seemed completely selective toward obtained cis-4-cyanomethyl-b-lactams were converted into the
the carboxylic acids 12a–c. Finally, aer inactivation and intended corresponding 4-carboxymethyl-b-lactams using
removal of the enzymes and ltration of the buffer salts, the nitrilase-P1-121 as the most active enzyme without affecting the
isolation of the target compounds was performed using sensitive four-membered ring, providing a useful substitute for
preparative HPLC (Method A). However, 4-carboxymethyl-b- the in this case inadequate classical chemical hydrolysis
lactams 12a and 12c could only be obtained in 12 and 16% yield approach. In addition, a straightforward pH-based extraction
respectively, implying a purication efficiency of only 17–27% protocol was designed for the efficient isolation of the carbox-
taking the incomplete conversion rate into account (Table 1). ylic acids thus formed. In this way, the one-step selective
Therefore, an alternative procedure was investigated (Method B). hydrolysis of 3-alkoxy/aryloxy-4-cyanomethyl-b-lactams toward
Aer extraction of the NaCl-saturated crude reaction mixtures the corresponding carboxylic acids using isolated nitrilase
with ethyl acetate, thus removing unreacted starting materials, enzymes, has been described for the rst time, integrating
the aqueous phases were acidied to pH 4 by means of HCl, biocatalytical processes into organic synthesis as a positive
turning the carboxylate ions into the organic solvent-soluble evolution tting in the current trends of sustainability and
carboxylic acids 12a,b, which could be recuperated in 43 and responsible entrepreneurship. The thus obtained new 4-car-
7
4% yield, respectively. This elegant solution, based on a selec- boxymethyl-b-lactams can be considered as polyvalent and
tive extraction method of the reaction mixture, is characterized versatile building blocks for further deployment in organic
by high purication efficiencies of 72–80% (Table 1).
synthesis.
Many efforts were devoted to the optimization of the enzy-
matic hydrolysis step in terms of reaction time and efficiency,
and the reaction conditions presented here should thus be
considered as an optimized procedure for this transformation.
Mechanistically, the formation of 4-carboxymethyl-b-lactams
Acknowledgements
The authors are indebted to the Research Foundation – Flan-
ders (FWO) and Ghent University – Belgium (BOF) for nancial
support.
12 can be explained as follows (Scheme 4). Nitrilase enzymes
consist of an essential amino acid sequence in their active site:
6
9,70
the Glu-Lys-Cys catalytic triade.
While glutamate and lysine
References and notes
are orienting the substrate in the correct position via non-
1
A. Fleming, Br. J. Exp. Pathol., 1929, 10, 226–236.
This journal is © The Royal Society of Chemistry 2016
RSC Adv., 2016, 6, 54573–54579 | 54577

View Article Online
RSC Advances
Paper
2
3
K. Bush, Curr. Opin. Pharmacol., 2012, 12, 527–534.
J. D. C. Yao and R. C. Moellering Jr, Manual of Clinical
Microbiology, 9th edn, 2007, vol. 1, pp. 1077–1113.
R. Jimenez, J. Duarte, A. Zarzuelo and M. Galisteo,
Antibiotics, 2005, 19–48.
M. A. Lopez-Ruz, M. Lopez-Gomez, J. Pasquau-Liano and
J. Jimenez-Alonso, Antibiotics, 2005, 83–142.
G. Veinberg, I. Potorocina and M. Vorona, Curr. Med. Chem.,
33 M. Sunagawa, A. Sasaki, H. Matsumura, K. Goda and
K. Tamoto, Chem. Pharm. Bull., 1994, 42, 1381–1387.
34 C. M. Gasparski, A. Ghosh and M. J. Miller, J. Org. Chem.,
1992, 57, 3546–3550.
35 M. A. Williams, M. J. Miller and N. P. Rath, J. Org. Chem.,
1991, 56, 1293–1296.
36 P. R. Guzzo, M. Teng and M. J. Miller, Tetrahedron, 1994, 50,
8275–8292.
37 A. Basak and S. Mandal, Tetrahedron Lett., 2002, 43, 4241–
4243.
4
5
6
7
2014, 21, 393–416.
P. D. Mehta, N. P. S. Sengar and A. K. Pathak, Eur. J. Med.
Chem., 2010, 45, 5541–5560.
38 L. Ban and G. Guanti, Eur. J. Org. Chem., 2002, 3745–3755.
8
9
I. Ojima and X. Qiu, J. Am. Chem. Soc., 1987, 109, 6537–6538. 39 K. C. Nicolaou and W. M. Dai, Angew. Chem., 1991, 103,
I. Ojima, E. S. Zuniga and J. D. Seitz, Top. Heterocycl. Chem.,
013, 30, 1–64.
0 B. Alcaide and P. Almendros, Curr. Med. Chem., 2004, 11,
921–1949.
1453–1481.
2
40 M. Gielen, H. Dalil, M. Biesemans, B. Mahieu, D. De Vos and
R. Willem, Appl. Organomet. Chem., 1999, 13, 515–520.
41 C. H. Sugisaki, Y. Ruland and M. Baltas, Eur. J. Org. Chem.,
2003, 672–688.
1
1
1
1 M. D'hooghe, S. Dekeukeleire, E. Leemans and N. De Kimpe,
Pure Appl. Chem., 2010, 82, 1749–1759.
42 K. Mollet, H. Goossens, N. Piens, S. Catak, M. Waroquier,
K. W. T ¨o rnroos, V. Van Speybroeck, M. D'hooghe and
N. De Kimpe, Chem.–Eur. J., 2013, 19, 3383–3396.
1
1
1
2 N. A. A. El-Kanzi, Heterocycl. Lett., 2013, 3, 81–109.
3 C. R. Pitts and T. Lectka, Chem. Rev., 2014, 114, 7930–7953.
4 M. T. Aranda, P. Perez-Faginas and R. G. Muniz, Adv. Org. 43 R. Grigg, M. Thornton-Pett, J. Xu and L.-H. Xu, Tetrahedron,
Synth., 2013, 6, 296–354. 1999, 55, 13841–13866.
5 B. Alcaide, P. Almendros, G. Cabrero and M. P. Ruiz, 44 W. Van Brabandt, M. Vanwalleghem, M. D'hooghe and N. De
Tetrahedron, 2012, 68, 10761–10768. Kimpe, J. Org. Chem., 2006, 71, 7083–7086.
6 J. Fetter, K. Lempert, M. Kajtar-Peredy, G. Simig and 45 S. Dekeukeleire, M. D'hooghe, M. Vanwalleghem, W. Van
G. Hornyak, J. Chem. Soc., Perkin Trans. 1, 1986, 1453–1458.
7 M. Shiozaki, N. Ishida, T. Hiraoka and H. Maruyama,
Tetrahedron, 1984, 40, 1795–1802.
8 B. Alcaide, P. Almendros, G. Cabrero and M. P. Ruiz, J. Org.
Chem., 2007, 72, 7980–7991.
9 R. J. Nash, A. Kato, C.-Y. Yu and G. W. J. Fleet, Future Med.
Chem., 2011, 3, 1513–1521.
1
1
1
1
1
Brabandt and N. De Kimpe, Tetrahedron, 2012, 68, 10827–
10834.
46 L. Jiao, Y. Liang and J. Xu, J. Am. Chem. Soc., 2006, 128, 6060–
6069.
47 B. Alcaide, M. F. Aly, C. Rodriguez and A. Rodriguez-Vicente,
J. Org. Chem., 2000, 65, 3453–3459.
48 F. Durrat, M. V. Sanchez, F. Couty, G. Evano and J. Marrot,
Eur. J. Org. Chem., 2008, 3286–3297.
20 Y. Nishimura, Curr. Top. Med. Chem., 2003, 3, 575–591.
2
1 P. Greimel, J. Spreitz, A. E. Stutz and T. M. Wrodnigg, Curr. 49 Y.-F. Ao, D.-H. Leng, D.-X. Wang, L. Zhao and M.-X. Wang,
Top. Med. Chem., 2003, 3, 513–523. Tetrahedron, 2014, 70, 4309–4316.
2 L. Somsak, V. Nagy, Z. Hadady, T. Docsa and P. Gergely, Curr. 50 J. Fetter, F. Bertha, T. Czuppon, M. Kajtar-Peredy and
Pharm. Des., 2003, 9, 1177–1189. K. Lempert, J. Chem. Res., Synop., 1995, 444–445.
3 C. A. Townsend, M. J. Bodner, R. M. Phelan and 51 G. Simig, G. Doleschall, G. Hornyak, J. Fetter, K. Lempert,
2
2
2
M. F. Freeman, WO2011072287A2, 2011.
J. Nyitrai, P. Huszthy, T. Gizur and M. Kajtar-Peredy,
4 M. J. Bodner, R. Li, R. M. Phelan, M. F. Freeman,
Tetrahedron, 1985, 41, 479–484.
K. A. Moshos, E. P. Lloyd and C. A. Townsend, 52 Y. Ito, Y. Kobayashi, T. Kawabata, M. Takase and
ChemBioChem, 2011, 12, 2159–2165. S. Terashima, Tetrahedron, 1989, 45, 5767–5790.
5 Y. Takahashi, H. Yamashita, S. Kobayashi and M. Ohno, 53 C. J. Ashcro, J. Brennan, C. E. Newall and S. M. Roberts,
Chem. Pharm. Bull., 1986, 34, 2732–2742. Tetrahedron Lett., 1984, 25, 877–880.
6 T. Yoshioka, R. Miyata, T. Tsuchida, H. Tone and 54 S. Kishimoto, M. Sendai, M. Tomimoto, S. Hashiguchi,
2
2
2
2
R. Okamoto, EP421440A2, 1991.
T. Matsuo and M. Ochiai, Chem. Pharm. Bull., 1984, 32,
7 D. G. Melillo, T. Liu, K. Ryan, M. Sletzinger and I. Shinkai,
Tetrahedron Lett., 1981, 22, 913–916.
8 P. Galletti, C. E. A. Cocuzza, M. Pori, A. Quintavalla,
2646–2659.
55 N. Ikota, H. Shibata and K. Koga, Chem. Pharm. Bull., 1985,
33, 3299–3306.
R. Musumeci and D. Giacomini, ChemMedChem, 2011, 6, 56 J. Fetter, K. Lempert, T. Gizur, J. Nyitrai, M. Kajtar-Peredy,
1
919–1927.
G. Simig, G. Hornyak and G. Doleschall, J. Chem. Soc.,
Perkin Trans. 1, 1986, 221–227.
2
3
3
9 T. Hara, A. Yoshida and N. Matsui, JP10077263A, 1998.
0 A. H. Berks, Tetrahedron, 1996, 52, 331–375.
57 J. D. Buynak, WO2014070774A1, 2014.
1 T. Yamanaka, M. Seki, T. Kuroda, H. Ohmizu and T. Iwasaki, 58 D.-H. Leng, D.-X. Wang, Z.-T. Huang and M.-X. Wang, Org.
Tetrahedron Lett., 1996, 37, 4967–4968. Biomol. Chem., 2010, 8, 4736–4743.
2 D. H. Shih, F. Baker, L. Cama and B. G. Christensen, 59 A. Banerjee, R. Sharma and U. C. Banerjee, Appl. Microbiol.
Heterocycles, 1984, 21, 29–40. Biotechnol., 2002, 60, 33–44.
3
54578 | RSC Adv., 2016, 6, 54573–54579
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6
6
6
0 T. Sugai, T. Yamazaki, M. Yokoyama and H. Ohta, Biosci., 66 R. de Regil and G. Sandoval, Biomolecules, 2013, 3, 812–847.
Biotechnol., Biochem., 1997, 61, 1419–1427.
67 T. Schafer, T. W. Borchert, V. S. Nielsen, P. Skagerlind,
K. Gibson, K. Wenger, F. Hatzack, L. D. Nilsson,
S. Salmon, S. Pedersen, H. P. Heldt-Hansen, P. B. Poulsen,
H. Lund, K. M. Oxenboell, G. F. H. Wu, H. Pedersen and
H. Xu, Adv. Biochem. Eng./Biotechnol., 2007, 105, 59–131.
68 Two nitrilase screening kits were kindly donated by Codexis
and Prozomix, from which nitrilase NIT-P1-121 (Codexis)
was found to give the best results.
1 M. Winkler, L. Martinkova, A. C. Knall, S. Krahulec and
N. Klempier, Tetrahedron, 2005, 61, 4249–4260.
2 V. K. Nigam, A. K. Khandelwal, A. Agarwal, A. S. Vidyarti,
M. K. Mohan, R. K. Gothwal and P. Ghosh, Recent Adv.
Microbiol., 2013, 1, 461–477.
6
6
3 M.-X. Wang, Top. Organomet. Chem., 2011, 36, 105–122.
4 K. Vervisch, M. D'hooghe, F. P. J. T. Rutjes and N. De Kimpe,
Org. Lett., 2012, 14, 106–109.
69 L. Martinkova and V. Kren, Curr. Opin. Chem. Biol., 2010, 14,
130–137.
65 K. Mollet, L. Decuyper, S. Vander Meeren, N. Piens, K. De
Winter, T. Desmet and M. D'hooghe, Org. Biomol. Chem., 70 C. Brenner, Curr. Opin. Struct. Biol., 2002, 12, 775–782.
015, 13, 2716–2725.
2
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