2-Oxoamide inhibitors of cytosolic group IVA phospholipase A2with reduced lipophilicity

Article abstract of DOI:10.1016/j.bmc.2016.07.057

Cytosolic GIVA phospholipase A₂(GIVA cPLA₂) initiates the eicosanoid pathway of inflammation and thus inhibitors of this enzyme constitute novel potential agents for the treatment of inflammatory diseases. Traditionally, GIVA cPLA

Full text of DOI:10.1016/j.bmc.2016.07.057

Accepted Manuscript
2-Oxoamide inhibitors of cytosolic group IVA phospholipase A2 with reduced
lipophilicity
Georgia Antonopoulou, Victoria Magrioti, Maroula G. Kokotou, Aikaterini
Nikolaou, Efrosini Barbayianni, Varnavas D. Mouchlis, Edward A. Dennis,
George Kokotos
PII:
S0968-0896(16)30581-8
DOI:
http://dx.doi.org/10.1016/j.bmc.2016.07.057
BMC 13170
Reference:
Bioorganic & Medicinal Chemistry
To appear in:
Received Date:
Revised Date:
Accepted Date:
27 February 2016
25 July 2016
26 July 2016
Please cite this article as: Antonopoulou, G., Magrioti, V., Kokotou, M.G., Nikolaou, A., Barbayianni, E., Mouchlis,
V.D., Dennis, E.A., Kokotos, G., 2-Oxoamide inhibitors of cytosolic group IVA phospholipase A2 with reduced
lipophilicity, Bioorganic & Medicinal Chemistry (2016), doi: http://dx.doi.org/10.1016/j.bmc.2016.07.057
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers
we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and
review of the resulting proof before it is published in its final form. Please note that during the production process
errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Graphical Abstract
Leave this area blank for abstract info.
2-Oxoamide inhibitors of cytosolic group IVA
phospholipase A2 with reduced lipophilicity
Georgia Antonopouloua,d, Victoria Magriotia, Maroula G. Kokotoua, Aikaterini Nikolaoua, Efrosini
Barbayiannia, Varnavas D. Mouchlisb,c, Edward A. Dennisb,c,*, George Kokotosa,*
aDepartment of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771,
Greece
bDepartment of Chemistry and Biochemistry, School of Medicine, MC 0601, University of California, San
Diego, La Jolla, CA 92093-0601, USA
cDepartment of Pharmacology, School of Medicine, MC 0601, University of California, San Diego, La Jolla, CA
92093-0601, USA
dInstitute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, Athens,
Greece

Bioorganic & Medicinal Chemistry
2-Oxoamide inhibitors of cytosolic group IVA phospholipase A2 with reduced
lipophilicity
Georgia Antonopouloua,d, Victoria Magriotia, Maroula G. Kokotoua, Aikaterini Nikolaoua, Efrosini
Barbayiannia, Varnavas D. Mouchlisb,c, Edward A. Dennisb,c,*, George Kokotosa,*
aDepartment of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, Athens 15771, Greece
bDepartment of Chemistry and Biochemistry, School of Medicine, MC 0601, University of California, San Diego, La Jolla, CA 92093-0601, USA
cDepartment of Pharmacology, School of Medicine, MC 0601, University of California, San Diego, La Jolla, CA 92093-0601, USA
dInstitute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, Athens, Greece
ARTICLE INFO
ABSTRACT
Article history:
Received
Received in revised form
Accepted
Cytosolic GIVA phospholipase A2 (GIVA cPLA2) initiates the eicosanoid pathway of
inflammation and thus inhibitors of this enzyme constitute novel potential agents for the
treatment of inflammatory diseases. Traditionally, GIVA cPLA2 inhibitors have suffered
systemically from high lipophilicity. We have developed a variety of long chain 2-oxoamides as
inhibitors of GIVA PLA2. Among them, AX048 was found to produce a potent analgesic effect.
We have now reduced the lipophilicity of AX048 by replacing the long aliphatic chain with a
chain containing an ether linked aromatic ring with in vitro inhibitory activities similar to
AX048.
Available online
Keywords:
GIVA cPLA2
Inhibitors
Lipophilicity
2-Oxoamides
Phospholipase A2
2009 Elsevier Ltd. All rights reserved.
1. Introduction
Among them, ecopladib7 (2, Fig 1) showed oral efficacy in
Cytosolic Group IVA phospholipase A2 (GIVA cPLA2) is an
enzyme which plays a central role in inflammatory diseases.1,2 It
catalyzes the hydrolysis of the ester bond at the sn-2 position of
glycerophospholipids releasing free fatty acids, including
arachidonic acid, and lysophospholipids. Arachidonic acid
initiates the cascade of bioactive eicosanoids, while
lysophospholipids may be converted to other bioactive lipids
such as platelet activating factor (PAF) or lyso-phosphatidic acid
(LPA). Therefore, inhibitors of PLA2 may regulate the
production of a large number of inflammatory mediators and
their discovery has attracted widespread interest in finding new
medicinal agents for the treatment of inflammatory diseases.
inflammation models and advanced to phase I clinical trials,
while giripladib (3, Fig 1) showed oral efficacy in vivo and was
advanced into a phase II clinical trial for osteoarthritis. However,
the trials were terminated because of standard gastrointestinal
issues. Another important class of inhibitors, pyrrolidine-based
compounds, was developed by Shionogi. Pyrrophenone (4, Fig 1)
is a potent inhibitor, which strongly inhibited arachidonic acid
release, prostaglandin E2, as well as thromboxane B2 and
leukotriene B4 formation in human whole blood.11,12 The
structurally related inhibitor, pyrroxyphene13 (5, Fig 1) displayed
anti-arthritic and anti-bone destructive action in a murine arthritis
model.14 A great number of 1,3-disubstituted propan-2-ones have
been synthesized and tested, for example compound 6.15-22 We
have developed various long chain 2-oxoamides as inhibitors of
GIVA PLA2.23-27 One of them, namely AX048 (7, Fig 1),28 was
found to be systemically bioavailable producing a potent
analgesic effect. In vivo, intrathecal (30 µg) and systemic (0.2–3
mg/kg i.p.) administration of AX048 blocked carrageenan
hyperalgesia and after systemic delivery in a model of spinally
mediated hyperalgesia induced by substance P.
A great variety of synthetic GIVA cPLA2 inhibitors have been
reported in the literature and they have been summarized in
recent review articles.2-4 The first inhibitor of GIVA cPLA2
reported was the arachidonoyl trifluoromethyl ketone (1, Fig 1).5
Wyeth has reported a series of indole-based inhibitors.6-10
* Corresponding authors. Tel.: +1 858 534 3055; fax: +1 858 534 7390 (E.A.D.);
tel.: +30 210 727 4462; fax: +30 210 727 4761 (G.K.).
E-mail addresses: edennis@ucsd.edu (E.A. Dennis), gkokotos@chem.uoa.gr
Usually, GIVA cPLA2 inhibitors suffer from high
lipophilicity, which has as a consequence poor aqueous solubility
and poor bioavailability. In the past, efforts to lower the
(G. Kokotos).

lipophilicity of GVIA cPLA2 inhibitors have been
Our goal in this study was to design inhibitors which retained the
potency of AX48, but with reduced lipophilicity.
29-31
accomplished.22,
As an example, Lehr and coworkers
developed 1,3-disubstituted propan-2-ones with reduced
lipophilicity.22 The aim of the present work is to develop 2-
oxoamides with reduced lipophilicity focusing on the inhibitor
AX048 which demonstrates analgesic effect.28 In an effort to
identify more “drug-like” inhibitors, several new 2-oxoamides
were designed and synthesized and their in vitro activities are
presented here.
The lipophilicity of the inhibitors is measured by the ClogP
value. In Figure 1, the ClogP values of several common GIVA
cPLA2 inhibitors, calculated by ChemOffice Ultra 11.00. are
presented. It is quite clear that these inhibitors present a common
drawback: high lipophilicity. The ClogP values for these
inhibitors range from 6.55 to 10.75.
Inhibitors with such high values are not expected to present
favorable ADME properties according to Lipinski’s rule of five.34
The main lipophilic part of the oxoamide inhibitor AX048 is the
long aliphatic chain. To decrease the lipophilicity, we envisaged
the replacement of it by chains incorporating an aromatic ring
along with one or two ether oxygens. These ether oxygens can be
placed either near or at remote distance from the activated
carbonyl, which interacts with the active site serine. Another
option is the introduction of polar functionalities such as a
sulfonamide or carboxylic group, at the end of the hydrophobic
chain which may reduce the lipophilicity.
2. Results and discussion
2.1. Design of inhibitors with reduced lipophilicity
The mechanistic details of GIVA cPLA2 abstraction of its
phospholipid substrate from the lipid-water interface at the
membrane surface have recently been described.32, Synthetic
33
lipophilic inhibitors of this enzyme are likely to partition into
membranes prior to interacting with the enzyme and good
inhibitors have all possessed substantial lipophilicity. When the
lipophilicity of an inhibitor decreases, the inhibitory potency may
decrease, but bioavailability may increase.
Figure 1. ClogP values for GIVA cPLA2 inhibitors.

The compounds shown in Figure 2 were designed specifically
to reduce lipophilicity without compromising inhibitory potency.
Scheme 2. Reagents and conditions: (a) NaOCl, TEMPO, NaBr, NaHCO3,
EtOAc/PhCH3/H2O 3:3:0.5, -5 oC; (b) i. NaHSO3, CH2Cl2, H2O; ii. KCN,
H2O; (c) conc. HCl; (d) KOH, EtOH/H2O.
Ethyl γ-amino butyrate (22) and ethyl 5-aminopentanoate (23)
were coupled with 2-hydroxy acids 21a-e and the products either
oxidized to 2-oxoamides 25a-c containing an ester group, or first
hydrolyzed and subsequently oxidized to 2-oxoamides 27a-d
containing a free carboxyl group (Scheme 3). 2-Oxoamide
derivative 28, containing a terminal free carboxyl group, was
obtained by oxidative conversion of the phenyl group of
compound 24e to carboxyl using NaIO4-RuCl3.38,39 At the same
time, the hydroxyamide functionality was also oxidized to an
oxoamide (Scheme 3).
Figure 2. Replacements of the long aliphatic chain of 2-oxoamides designed
in this work.
2.2. Synthesis of inhibitors
For the synthesis of the designed 2-oxoamides, a variety of 2-
hydroxy acids were synthesized as shown in Schemes 1 and 2.
First, the known esters 835 and 936, and esters 12 and 14,
synthesized as depicted in Scheme 1, were reduced to alcohols
15a-d. Amino alcohol 18, protected by the tosyl group, was
prepared by the reduction of acid 16 using the mixed
anhydride/NaBH4 method37 (Scheme 1). Alcohols 15a-d and 18
were oxidized to aldehydes and subsequently converted to
cyanohydrins 19a-e (Scheme 2). 2-Hydroxy acids 21a-e were
obtained by conversion to hydroxyamides and hydrolysis under
basic conditions.
Scheme 3. Reagents and conditions: (a) 21a-e, Et3N, WSCI, HOBt, CH2Cl2;
(b) Dess-Martin periodinane, CH2Cl2; (c) NaOH 1N, dioxane/H2O 9:1; (d)
NaIO4, RuCl3.H2O, CH3CN/CCl4/H2O 1:1:2.
Compound 21d was also coupled wih tert-butyl 4-
aminobutanoate (30). Oxidation of compound 31, followed by
treatment with trifluoroacetic acid afforded the target compound
33 (Scheme 4).
Scheme 4. Reagents and conditions: (a) 21d, Et3N, WSCI, HOBt, CH2Cl2;
(b) Dess-Martin periodinane, CH2Cl2; (c) 50% TFA/CH2Cl2.
2.3. In vitro inhibition of GIVA cPLA2, GVIA iPLA2 and GV
sPLA2
All synthesized inhibitors were tested for inhibition of
human GIVA cPLA2, GVIA iPLA2 and GV sPLA2 using
previously described mixed micelle-based assays.24-26 The
inhibition results are presented in Table 1, either as percent
inhibition or as XI(50) values. At first, the percent of inhibition
for each PLA2 enzyme at 0.091 mole fraction of each inhibitor
was determined. Then, the XI(50) values were measured for
compounds that displayed greater than 85% inhibition. The
XI(50) is the mole fraction of the inhibitor in the total substrate
interface required to inhibit the enzyme by 50%. The ClogP
values of all synthesized inhibitors are also summarized in Table
1.
Scheme 1. Reagents and conditions: (a) Br-P+Ph3(CH2)9COOCH3, NaH,
THF, reflux; (b) H2, 10% Pd/C, EtOH; (c) K2CO3, ethyl 4-bromobutyrate,
acetone, reflux; (d) DIBALH, Et2O or LiAlH4, THF, reflux; (e) TsCl, NMM,
THF; (f) i. NMM, ClCO2Et, THF; ii. NaBH4, MeOH.

Table 1. Inhibition of PLA2 by 2-oxoamidesa
GIVA cPLA2
GVIA iPLA2
GV sPLA2
Number
Structure
ClogPb
7.61
% Inhibition
XI(50)
% Inhibition
XI(50)
% Inhibition
0.022 ±
0.009
0.027 ±
0.009
AX04828
AX00628
25b
0.024 ±
0.015
6.63
7.39
N.D.
0.014 ±
0.003
49.3 ± 2.0
>85
94.7 ± 0.5
40.6 ± 5.9
33.8 ± 6.0
0.020 ±
0.006
0.013 ±
0.003
6.30
6.41
95.1 ± 0.6
25a
27b
0.023 ±
0.005
N.D.
>85
N.D.
0.016 ±
0.004
5.32
4.94
N.D.
N.D.
>85
N.D.
27a
32
63.6 ± 2.6
81.1 ± 1.0
0.013 ±
0.002
N.D.
N.D.
4.82
5.69
88.0 ± 0.9
59.3 ± 3.1
82.5 ± 1.4
N.D.
27d
25c
27c
4.71
4.61
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
28
aAverage percent inhibition and standard error (n = 3) are reported for each compound at 0.091 mol fraction. XI(50) values were determined for inhibitors with
greater than 85% inhibition. N.D. signifies compounds with less than 25% inhibition (or no detectable inhibition). bCalculated by ChemOffice Ultra 11.00.
Initially, the long aliphatic chain of AX048 was
replaced by chains containing an aromatic group along with an
ether group. Analog 25b exhibited very weak inhibitory activity
on GIVA cPLA2, but considerable activity on GVIA iPLA2.
However, analog 25a inhibited both the intracellular enzymes
GIVA cPLA2 and GVIA iPLA2 with XI(50) values of 0.020 and
0.013, respectively. In the case of 2-oxoamides containing an
ester group, the position of the O atom influences the activity
toward GVIA cPLA2. When the oxygen is at the δ-position from
the activated carbonyl group, inhibitor 25b only weakly inhibits
cPLA2, while when it is on the other side of the aromatic group
with a greater distance from the activated carbonyl, good
inhibition is observed. The 2-oxoamides 27b and 27a, that
contain a free carboxyl group, selectively inhibited GIVA cPLA2
without affecting GVIA iPLA2 activity. This is in agreement with
our previous observations that 2-oxoamides containing a free
carboxyl group selectively inhibit GIVA cPLA2.25,26,40 The
inhibitor containing the O atom nearer to the activated carbonyl
presented less inhibitory potency than the one containing the O
atom on the other side of the ring. Inhibitor 25a not only
possesses lower lipophilicity (ClogP 6.30) than that of AX048
(ClogP 7.61), but also exhibits the same inhibition of both GIVA
cPLA2 and GVIA iPLA2 as AX048. In addition, the
corresponding analog 27a presented even better potency toward
GIVA cPLA2 (XI(50) values of 0.016) with a significantly lower
lipophilicity (ClogP 5.32).
Compound 32, containing two ether oxygens, did not
present any significant inhibition of GIVA cPLA2. However,
increasing the distance between the oxoamide functionality and
the free carboxyl by one carbon atom led to increase of the
inhibitory potency on GIVA cPLA2. Compound 27d presents a
XI(50) value of 0.013 for GIVA cPLA2 and at the same time
reduced lipophilicity (ClogP 4.82). Thus, compounds 27a and
27d clearly presented higher inhibitory potency on GIVA cPLA2

in comparison to AX048 and its corresponding acid AX00628 and
considerably lower lipophilicity. In addition, both of them are
more potent inhibitors of GIVA cPLA2 than the widely known
and commercially available inhibitor AATFMK (XI(50) value of
0.036).21
room temperature. The organic solvent was evaporated under
reduced pressure, and H2O (5 mL) was added dropwise. The
product was extracted with Et2O (3 × 5 mL), and the combined
organic layers were washed with brine, dried over Na2SO4, and
concentrated under reduced pressure. The residue was purified by
column chromatography using petroleum ether (bp 40-60
In another approach to reduce the lipophilicity, a
sulfonamide group was introduced at the end of the long chain.
Both the ethyl ester 25c and the free acid 27c presented lower
lipophilicity (ClogP 5.69 and 4.71, respectively) than AX048.
However, the in vitro activities were dramatically decreased.
Only 25c presented a weak inhibition of GIVA cPLA2.
Additionally, a carboxylic acid group was introduced at the end
of the long chain, but this substitution resulted in a sizable
reduction in the lipophilicity (ClogP 4.61). Unfortunately, this
compound was inactive toward both GIVA cPLA2 and GVIA
iPLA2. Thus, although the introduction of the sulfonamide or the
carboxyl functionalities led to compounds with reduced
lipophilicities (25c, 27c, 28), these compounds displayed a
dramatic loss in the inhibitory activity.
1
°C)/EtOAc 95:5 as eluent. Yield 76%; white oil; H NMR (200
MHz, CDCl3): δ 7.34-7.14 (m, 5H, Ph), 6.38 (d, 1H, PhCH=CH,
J = 11.8 Hz), 5.70-5.57 (dt, 1H, PhCH=CH, J1 = 11.8 Hz, J2 =
7.0 Hz), 3.63 (s, 3H, OCH3), 2.35-2.20 (m, 4H, CH2CO, CH2),
1.75-1.55 (m, 2H, CH2), 1.40-1.35 (m, 2H, CH2), 1.34-1.10 (m,
10H, 5 × CH2); 13C NMR (50 MHz, CDCl3): δ 174.2, 137.7,
133.1, 128.7, 128.0, 126.3, 125.8, 51.3, 34.0, 33.0, 29.9, 29.3,
29.2, 29.1, 29.0, 28.5, 24.9. Anal. Calcd for C19H28O2: C, 79.12;
H, 9.78. Found: C, 79.01; H, 9.92.
4.2.2. Methyl 12-phenyldodecanoate (12)
To a solution of 11 (288 mg, 1.0 mmol) in EtOH (5 mL)
(through which N2 had been passed for 5 min), 10% Pd/C
catalyst (11 mg) was added. The reaction mixture was stirred
under H2 atmosphere overnight at room temperature. The catalyst
was removed by filtration through a pad of Celite, and the
organic solvent was evaporated under reduced pressure. The
residue was purified by column chromatography using petroleum
3. Conclusion
Lipophilicity is a very important parameter in the case of
GIVA cPLA2 inhibitors because this enzyme exhibits its catalytic
action at the lipid-water interface. Thus, a potential PLA2
inhibitor has to possess substantial lipophilicity, which usually
leads to unfavorable ADME properties. Efforts to reduce the
lipophilicity are usually accompanied by reduced inhibitory
activity. We achieved a reduction in the lipophilicity of the in
vivo active 2-oxoamide inhibitor AX048 by replacing the long
aliphatic chain with a chain containing an aromatic ring along
with one or two ether oxygens. These new derivatives (25a, 27a
and 27d) possess in vitro inhibitory activities against GIVA
cPLA2 and GVIA iPLA2 similar to AX048. Thus, we achieved a
reduction in the lipophilicity without compromising inhibitory
potency.
1
ether (bp 40-60 °C)/EtOAc as eluent. Yield 81%; oil; H NMR
(200 MHz, CDCl3): δ 7.39-7.20 (m, 5H, Ph), 3.74 (s, 3H, OCH3),
2.69 (t, 2H, PhCH2, J = 7.2 Hz), 2.38 (t, 2H, CH2CO, J = 7.4 Hz),
1.78-1.60 (m, 4H, 2 × CH2), 1.42-1.15 (m, 14H, 7 x CH2) 13C
NMR (50 MHz, CDCl3): δ 174.0, 142.7, 128.2, 128.1, 125.4,
51.2, 35.9, 34.0, 31.4, 29.5, 29.4, 29.3, 29.2, 29.1, 29.0, 24.8.
Anal. Calcd for C19H30O2: C, 78.57; H, 10.41. Found: C, 78.22;
H, 10.58.
4.2.3. Ethyl 4-(4-(hexyloxy)phenoxy)butanoate (14)
To a stirred solution of 13 (194 mg, 1.0 mmol) in acetone (8
mL), K2CO3 (414 mg, 3 mmol) and ethyl 4-bromobutyrate (0.2
mL, 1.5 mmol) were added and the reaction mixture was refluxed
overnight. The organic solvent was evaporated under reduced
pressure and the residue was treated with H2O to remove
potassium carbonate and extracted with CH2Cl2 (3 × 5 mL). The
organic solvent was evaporated under reduced pressure and the
residue was purified by column chromatography using petroleum
ether (bp 40-60 °C)/EtOAc 8/2 as eluent. Yield 100%; colourless
oil; 1Η NMR (200 MHz, CDCl3): δ 6.90-6.70 (m, 4H, arom), 4.09
(q, 2H, OCH2CH3, J = 6.0 Hz), 3.90 (t, 2H, OCH2, J = 6.0 Hz),
3.84 (t, 2H, OCH2, J = 6.0 Hz), 3.42 (t, 2H, CH2COO, J = 6.0
Hz), 2.60-2.30 (m, 4H, 2 x CH2), 2.20-1.90 (m, 4H, 2 x CH2),
1.71 (quintet, 2H, CH2, J = 6.0 Hz), 1.22 (t, 3H, OCH2CH3, J =
6.0 Hz), 0.86 (t, 3H, CH3, J = 6.0 Hz); 13C NMR (50 MHz,
CDCl3): δ 173.1, 153.2, 152.7, 115.1, 68.4, 67.1, 60.2, 32.3, 30.7,
29.2, 27.6, 25.6, 24.6, 14.1, 13.9. Anal. Calcd for C18H28O4: C,
70.10; H, 9.15. Found: C, 69.98; H, 9.30.
4. Experimental section
4.1. General
Melting points were determined on a Buchi 530 apparatus
and are uncorrected. NMR spectra were recorded on a Varian
1
Mercury spectrometer. H and 13C NMR spectra were recorded at
200 MHz and 50 MHz respectively in CDCl3 or as specified.
Chemical shifts are given in ppm, and peak multiplicities are
described as follows: s, singlet, d, doublet, t, triplet and m,
multiplet. Electron spray ionization (ESI) mass spectra were
recorded on a Finnigan, Surveyor MSQ Plus spectrometer. TLC
plates (Silica Gel 60 F254) and Silica Gel 60 (70-230 or 230-400
mesh) for column chromatography were purchased from Merck.
Spots were visualized with UV light and/or phosphomolybdic
acid and/or ninhydrin, both in EtOH. Dichloromethane was dried
by standard procedures and stored over molecular sieves. All
other solvents and chemicals were reagent grade and used
without further purification.
4.2.4. General method for the reduction of esters to alcohols
To a stirred solution of the ester 8, 9 or 12 (1.0 mmol) in dry
Et2O (10 mL), a solution of 1.0 M DIBALH in hexane (2.5 mL,
2.5 mmol) was added dropwise under N2 atmosphere at room
temperature. The mixture was stirred for 2 h after the addition
was complete, and then H2O (5 mL) was added dropwise. The
entire mixture was stirred for 30 more min, and then filtered
through a pad of Celite. The filtrate was evaporated under
reduced pressure and the residue was purified by column
chromatography using petroleum ether (bp 40-60 °C)/EtOAc as
eluent.
The synthesis of compounds 8,35 936 has been described
previously.
4.2. Chemistry
4.2.1. (E)-Methyl 12-phenyldodec-11-enoate (11)
To a stirred solution of Br-P+Ph3(CH2)9COOCH3 (579 mg,
1.1 mmol) in dry THF (4 mL) under N2 atmosphere, NaH (53
mg, 2.2 mmol) was added, followed by a solution of
benzaldehyde (106 mg, 1.0 mmol) in dry THF (0.3 mL). The
reaction mixture was stirred under N2 atmosphere overnight at

4.2.4.1. 5-(4-(Hexyloxy)phenyl)pentan-1-ol (15a). Yield 72%;
oil; H NMR (200 MHz, CDCl3): δ 7.29 (d, 2H, arom, J = 8.8
7.25 (d, 2H, arom, J = 8.0 Hz), 5.08 (br s, 1H, NH), 2.94-2.63
(m, 2H, NHCH2), 2.37 (s, 3H, CH3), 2.29 (t, 2H, CH2COOH, J=
7.4 Hz), 1.62-0.95 (m, 16H, 8 x CH2); 13C NMR (50 MHz,
CDCl3): δ 179.3, 143.2, 136.8, 129.6, 127.0, 43.1, 33.9, 29.3,
29.2, 29.1, 29.0, 28.9, 26.4, 24.6, 21.4. Anal. Calcd for
C18H29NO4S: C, 60.82; H, 8.22; N, 3.94. Found: C, 60.72; H,
8.39; N, 3.84.
1
Hz), 7.03 (d, 2H, arom, J = 8.8 Hz), 4.15 (t, 2H, CH2OPh, J = 6.6
Hz), 3.84 (t, 2H, CH2OH, J = 6.2 Hz), 2.78 (t, 2H, PhCH2, J = 7.4
Hz), 2.43 (bs, 1H, OH), 2.05-1.95 (m, 2H, CH2), 1.88-1.45 (m,
12H, 6 x CH2), 1.13 (t, 3H, CH3, J= 6.6 Hz); 13C NMR (50 MHz,
CDCl3): δ 157.2, 134.4, 129.1, 114.3, 68.0, 62.8, 34.9, 32.6, 31.6,
31.4, 29.3, 25.7, 25.3, 22.6, 14.0. Anal. Calcd for C17H28O2: C,
77.22; H, 10.67. Found: C, 77.06; H, 10.85.
4.2.7. N-(11-Hydroxyundecyl)-4-methylbenzenesulfonamide
(18)
4.2.4.2. 4-(4-Octylphenoxy)butan-1-ol (15b). Yield 84%; white
To a stirred solution of 17 (355 mg,1.0 mmol) in dry THF (5
mL) at -10 °C, NMM (0.11 mL, 1.0 mmol) was added, followed
by ClCOOEt (0.096 mL, 1.0 mmol). After 10 min, NaBH4 (0.11
g, 3.0 mmol) was added in one portion. MeOH (10 mL) was then
added dropwise to the mixture over a period of 10 min at 0 °C.
The solution was stirred for an additional 10 min and the organic
solvents were evaporated under reduced pressure. The residue
was neutralized with 1M aqueous KHSO4 and the product was
extracted with EtOAc (3 × 10 mL). The organic phase was
washed with 1M aqueous KHSO4 (5 mL), H2O (10 mL), 5%
aqueous NaHCO3 (5 mL), and H2O (10 mL), dried over Na2SO4,
and the solvent was evaporated under reduced pressure. The
residue was purified by column chromatography using
CHCl3/MeOH 95:5 as eluent. Yield 45%; white solid; mp 63-
65oC; 1H NMR (200 MHz, CDCl3): δ 7.72 (d, 2H, arom, J = 8.0
Hz), 7.22 (d, 2H, arom, J = 8.0 Hz), 4.68 (t, 1H, NH, J = 6.4 Hz),
3.60 (t, 2H, CH2OH, J= 6.6 Hz), 2.98-2.80 (m, 2H, NHCH2),
2.61 (bs, 1H, OH), 2.40 (s, 3H, CH3), 1.62-1.10 (m, 18H, 9 x
CH2); 13C NMR (50 MHz, CDCl3): δ 143.2, 137.8, 129.6, 127.0,
63.0, 43.1, 32.7, 29.5, 29.3, 29.0, 26.4, 25.6, 21.5. Anal. Calcd
for C18H31NO3S: C, 63.31; H, 9.15; N, 4.10. Found: C, 63.21; H,
9.22; N, 4.01.
o
solid; mp 42-44 C; 1H NMR (200 MHz, CDCl3): δ 7.09 (d, 2H,
arom, J = 8.8 Hz), 6.82 (d, 2H, arom, J = 8.8 Hz), 3.99 (t, 2H,
CH2OPh, J = 5.8 Hz), 3.73 (t, 2H, CH2OH, J = 5.8 Hz), 2.55 (t,
2H, PhCH2, J = 7.4 Hz), 2.38 (bs, 1H, OH), 1.98-1.20 (m, 16H, 8
x CH2), 0.89 (t, 3H, CH3, J= 6.2 Hz); 13C NMR (50 MHz,
CDCl3): δ 156.8, 135.2, 129.2, 114.3, 67.7, 62.6, 35.0, 31.9, 31.7,
29.5, 29.4, 29.2, 25.9, 22.6, 14.1. Anal. Calcd for C18H30O2: C,
77.65; H, 10.86. Found: C, 77.36; H, 10.98.
4.2.4.3. 12-Phenyldodecan-1-ol (15c). Yield 99%; white solid;
o
1
mp 42-44 C; H NMR (200 MHz, CDCl3): δ 7.39-7.21 (m, 5H,
Ph), 3.71 (t, 2H, CH2OH, J = 6.6 Hz), 2.68 (t, 2H, PhCH2, J= 7.4
Hz), 2.56 (bs, 1H, OH), 1.70-1.58 (m, 4H, 2 × CH2), 1.45-1.24
(m, 16H, 8 x CH2); 13C NMR (50 MHz, CDCl3): δ 142.9, 128.4,
128.2, 125.5, 63.1, 36.0, 32.8, 31.5, 29.6, 29.5, 29.4, 29.3, 25.7.
Anal. Calcd for C18H30O: C, 82.38; H, 11.52. Found: C, 82.16; H,
11.79.
4.2.5. 4-(4-(Hexyloxy)phenoxy)butan-1-ol (15d).
To a stirred solution of the ester 14 (308 mg, 1.0 mmol) in dry
THF (3.3 mL) a solution of 1.0 M LiAlH4 in THF (1.1 mL, 1.1
mmol) was added dropwise under N2 atmosphere and the mixture
was refluxed for 4 h. After cooling to room temperature, HCl 1N
(4.4 mL, 4.4 mmol) was added dropwise and the mixture was
stirred for 1 h. The solvent was evaporated under reduced
pressure and AcOEt and H2O were added. The aqueous layer was
separated and washed with EtOAc. The combined organic layers
were washed with brine and dried over anhydrous Na2SO4. The
solvent was evaporated under reduced pressure and the residue
was purified by column chromatography using petroleum ether
(bp 40-60 °C)/EtOAc 6/4 as eluent. Yield 65%; white solid; mp
4.2.8. General method for the synthesis of cyanohydrins 19a-e
To a solution of the alcohol 15a-d or 18 (1.0 mmol) in a
mixture of toluene (3 mL) and EtOAc (3 mL), a solution of NaBr
(0.11 g, 1.1 mmol) in water (0.5 mL) was added followed by
AcNH-TEMPO (2.2 mg, 0.01 mmol). To the resulting biphasic
system, which was cooled at 0 oC, an aqueous solution of 0.35 M
NaOCl (3.1 mL, 1.1 mmol) containing NaHCO3 (0.25 g, 3 mmol)
was added dropwise under vigorous stirring, at 0 oC over a period
of 1 h. After the mixture had been stirred for a further 15 min at 0
oC, EtOAc (10 mL) and H2O (10 mL) were added. The aqueous
layer was separated and washed with EtOAc (2 × 10 mL). The
combined organic layers were washed consecutively with 5%
aqueous citric acid (10 mL) containing KI (0.04 g), 10% aqueous
Na2S2O3 (10 mL), and brine and dried over Na2SO4. The solvents
were evaporated under reduced pressure and the residue was used
without any further purification.
o
1
49-51 C; Η NMR (200 MHz, CDCl3): δ 6.80-6.60 (m, 4H,
arom), 3.79 (t, , 2H, OCH2, J = 6.0 Hz), 3.75 (t, 2H, OCH2, J =
6.0 Hz), 3.54 (t, 2H, CH2OH, J = 6.0 Hz), 3.06 (bs, 1H, OH),
1.80-1.40 (m, 6H, 3 x CH2), 1.40-1.10 (m, 6H, 3 x CH2), 0.78 (t,
3H, CH3, J = 6.0 Hz); 13C NMR (50 MHz, CDCl3): δ 152.9,
152.6, 115.0, 68.2, 68.0, 61.8, 31.3, 29.0, 25.6, 25.4, 22.3, 20.6,
13.8. Anal. Calcd for C16H26O3: C, 72.14; H, 9.84. Found: C,
72.02; H, 9.98.
To a stirred solution of the aldehyde (1 mmol) in CH2Cl2
(1.25 mL), a solution of NaHSO3 (156 mg, 1.5 mmol) in water
(0.25 mL) was added and the mixture was vigorously stirred for
30 min at room temperature. The organic solvent was evaporated
under reduced pressure, water was added and the mixture was
4.2.6. 11-(4-Methylphenylsulfonamido)undecanoic acid (17)
To a solution of 11-amino-undecanoic acid (16) (201 mg, 1.0
mmol) in dry THF (1 mL), N-methylmorpholine was added (0.1
mL, 1.0 mmol) followed by a solution of tosyl chloride (191 mg,
1.0 mmol) in dry THF (1 mL), dropwise over 15 minutes. The
reaction mixture was then stirred for 3 h. The organic solvent was
evaporated under reduced pressure, H2O (5 mL) was added, and
the pH was adjusted to 2 with 6N HCl. The product was
extracted with CHCl3 (3 × 5 mL), and the combined organic
layers were washed with brine, dried over Na2SO4, and
concentrated under reduced pressure. The residue was purified by
column chromatography using CHCl3/MeOH 95:5 as eluent.
Yield 30%; white solid; mp 78-80oC; 1H NMR (200 MHz,
CDCl3): δ 9.60 (br s, 1H, COOH), 7.70 (d, 2H, arom, J = 8.0 Hz),
o
cooled at 0 C. Then, a solution of KCN (98 mg, 1.5 mmol) in
water (0.25 mL) was added dropwise over a period of 3.5 h and
the mixture was left under stirring overnight at room temperature.
The aqueous suspension was extracted with CH2Cl2 (2 × 5 mL).
The combined organic layers were washed with brine and dried
over Na2SO4. The solvent was evaporated under reduced pressure
and the residue was purified by column chromatography using
petroleum ether (bp 40-60 °C)/EtOAc as eluent.
4.2.8.1 6-(4-(Hexyloxy)phenyl)-2-hydroxyhexanenitrile (19a).
1
Yield 80%; oil; H NMR (200 MHz, CDCl3): δ 7.09 (d, 2H,
arom, J = 8.8 Hz), 6.84 (d, 2H, arom, J = 8.8 Hz), 4.44 (t, 1H,

CHOH, J = 7.0 Hz), 3.95 (t, 2H, CH2OPh, J= 6.6 Hz), 2.85 (bs,
1H, OH), 2.59 (t, 2H, PhCH2, J = 7.0 Hz), 1.92-1.74 (m, 4H, 2 ×
CH2), 1.71-1.43 (m, 6H, 3 x CH2), 1.40-1.31 (m, 4H, 2 x CH2),
0.92 (t, 3H, CH3, J = 7.0 Hz); 13C NMR (50 MHz, CDCl3): δ
157.3, 133.8, 129.2, 119.9, 114.5, 68.1, 61.2, 35.0, 34.6, 31.6,
30.9, 29.2, 25.7, 24.1, 22.6, 14.0. Anal. Calcd for C18H27NO2: C,
74.70; H, 9.40; N, 4.84. Found: C, 74.58; H, 9.56; N, 4.73.
8.4 Hz), 6.32 (br s, 1H, NH), 5.52 (br s, 1H, NH), 4.18-4.05 (m,
1H, CHOH), 3.93 (t, 2H, CH2OPh, J= 6.6 Hz), 2.57 (t, 2H, CH2,
J= 7.4 Hz), 2.40 (bs, 1H, OH), 2.25-1.98 (m, 2H, CH2), 1.93-1.10
(m, 12H, 6 x CH2), 0.91 (t, 3H, CH3, J= 6.6 Hz); 13C NMR (50
MHz, CDCl3): δ 174.2, 157.3, 133.9, 129.1, 114.6, 74.9, 68.0,
35.8, 35.0, 31.4, 30.8, 29.3, 25.6, 24.4, 22.6, 14.0. Anal. Calcd
for C18H29NO3: C, 70.32; H, 9.51; N, 4.56. Found: C, 70.26; H,
9.62; N, 4.47.
4.2.8.2. 2-Hydroxy-5-(4-octylphenoxy)pentanenitrile (19b).
o
1
Yield 96%; white solid; mp 50-52 C; H NMR (200 MHz,
CDCl3): δ 7.11 (d, 2H, arom, J = 8.4 Hz), 6.83 (d, 2H, arom, J =
8.4 Hz), 4.61 (br s, 1H, CHOH), 4.12-3.95 (m, 2H, PhOCH2),
3.46 (br s, 1H, OH), 2.55 (t, 2H, CH2Ph, J= 7.6 Hz), 2.15-1.95
(m, 4H, 2 x CH2), 1.65-1.50 (m, 2H, CH2), 1.38-1.19 (m, 10H, 5
x CH2), 0.90 (t, 3H, CH3, J = 6.2); 13C NMR (50 MHz, CDCl3): δ
156.2, 135.8, 129.3, 119.8, 114.3, 67.2, 61.0, 35.0, 32.6, 31.8,
31.7, 29.4, 29.2, 24.7, 22.7, 14.1. Anal. Calcd for C19H29NO2: C,
75.21; H, 9.63; N, 4.62. Found: C, 75.11; H, 9.78; N, 4.54.
4.2.9.2. 2-Hydroxy-5-(4-octylphenoxy)pentanamide (20b).
o
1
Yield 67%; white solid; mp 130-132 C; H NMR (200 MHz,
CDCl3): δ 7.05 (d, 2H, arom, J = 8.4 Hz), 6.80 (d, 2H, arom, J =
8.4 Hz), 6.31 (br, 1H, NH), 5.63 (br, 1H, NH), 4.15-4.05 (m, 1H,
CHOH), 3.97 (t, 2H, PhOCH2, J= 5.8 Hz), 2.52 (t, 2H, CH2Ph, J=
7.2 Hz), 2.38 (bs, 1H, OH), 2.04-1.77 (m, 4H, 2 x CH2), 1.78-
1.65 (m, 1H, CHH), 1.60-1.45 (m, 3H, 1 x CH2, CHH), 1.38-1.02
(m, 8H, 4 x CH2), 0.89 (t, 3H, CH3, J= 6.2 Hz); 13C NMR (50
MHz, CDCl3): δ 174.1, 156.4, 135.6, 129.2, 114.3, 75.0, 67.5,
35.8, 35.0, 32.0, 31.7, 31.4, 29.4, 29.3, 24.8, 22.0, 14.1. Anal.
Calcd for C19H31NO3: C, 70.99; H, 9.72; N, 4.36. Found: C,
70.87; H, 9.81; N, 4.28.
4.2.8.3. 2-Hydroxy-13-phenyltridecanenitrile (19c). Yield
o
1
90%; white solid; mp 36-38 C; H NMR (200 MHz, CDCl3): δ
7.40-7.21 (m, 5H, Ph), 4.52 (t, 1H, CHOH, J= 7.0 Hz), 2.89 (br s,
1H, OH), 2.68 (t, 2H, PhCH2, J= 7.4 Hz), 1.96-1.85 (m, 2H,
CH2), 1.78-1.60 (m, 2H, CH2), 1.60-1.45 (m, 2H, CH2), 1.45-1.10
(m, 14H, 7 x CH2); 13C NMR (50 MHz, CDCl3): δ 142.9, 128.4,
128.2, 125.5, 120.0, 61.3, 35.9, 35.1, 29.5, 29.4, 29.3, 29.2, 28.9,
24.5. Anal. Calcd for C19H29NO: C, 79.39; H, 10.17; N, 4.87.
Found: C, 79.28; H, 10.28; N, 4.75.
4.2.9.3. 2-Hydroxy-13-phenyltridecanamide (20c). Yield 73%;
white solid; mp 117-119 oC; 1H NMR (200 MHz, CDCl3): δ 7.27-
7.17 (m, 5H, Ph), 6.33 (br s, 1H, NH), 5.52 (br s, 1H, NH), 4.20-
4.02 (m, 1H, CHOH), 2.61 (t, 2H, PhCH2, J= 7.4 Hz), 2.46 (br s,
1H, OH), 1.95-1.78 (m, 1H, CHH), 1.75-1.50 (m, 3H, CHH,
CH2), 1.48-1.02 (m, 16H, 8 x CH2); 13C NMR (50 MHz, CDCl3):
δ 174.1, 142.9, 128.4, 128.3, 125.5, 75.0, 36.0, 34.8, 31.4, 29.5,
29.4, 29.2, 29.1, 28.0. Anal. Calcd for C19H31NO2: C, 74.71; H,
10.23; N, 4.59. Found: C, 74.63; H, 10.35; N, 4.48.
4.2.8.4.
5-(4-(Hexyloxy)phenoxy)-2-hydroxypentanenitrile
1
(19d). Yield 45%; colourless oil; Η NMR (200 MHz, CDCl3): δ
6.90-6.70 (m, 4H, arom), 4.55 (t, 1H, CHOH, J = 6.0 Hz), 3.94 (t,
2H, OCH2, J = 6.0 Hz), 3.89 (t, 2H, OCH2, J = 6.0 Hz), 2.10-1.90
(m, 4H, 2 x CH2), 1.74 (quintet, 2H, CH2, J = 6.0 Hz), 1.60-1.20
(m, 6H, 3 x CH2), 0.89 (t, 3H, CH3, J = 6.0 Hz); 13C NMR (50
MHz, CDCl3): δ 153.4, 152.3, 119.9, 115.4, 68.6, 67.7, 60.8,
32.3, 31.5, 29.2, 25.6, 24.6, 22.5, 14.0. Anal. Calcd for
C17H25NO3: C, 70.07; H, 8.65; N, 4.81. Found: C, 69.90; H, 8.85;
N, 4.92.
4.2.9.4.
5-(4-(Ηexyloxy)phenoxy)-2-hydroxypentanamide
o 1
(20d). Yield 65%; white solid; mp 146-148 C; Η NMR (200
MHz, CDCl3): δ 6.90-6.70 (m, 4H, arom), 6.58 (bs, 1H, NH),
5.48 (bs, 1H, NH), 4.30-4.10 (m, 1H, CHOH), 3.98 (t, 2H, OCH2,
J = 6.0 Hz), 3.89 (t, 2H, OCH2, J = 6.0 Hz), 2.10-1.50 (m, 6H, 3
x CH2), 1.50-1.20 (m, 6H, 3 x CH2), 0.89 (t, 3H, CH3, J = 6.0
Hz); 13C NMR (50 MHz, CDCl3): δ 172.6, 153.2, 152.6, 115.3,
71.1, 68.6, 68.3, 31.4, 31.1, 29.1, 25.5, 25.0, 22.4, 13.8. Anal.
Calcd for C17H27NO4: C, 65.99; H, 8.80; N, 4.53. Found: C,
65.79; H, 8.99; N, 4.68.
4.2.8.5.
N-(11-Cyano-11-hydroxyundecyl)-4-
methylbenzenesulfonamide (19e). Yield 73%; white solid; mp
77-79 C; 1H NMR (200 MHz, CDCl3): δ 7.72 (d, 2H, arom, J =
o
8.4 Hz), 7.28 (d, 2H, arom, J = 8.4 Hz), 4.73 (t, 1H, NH, J= 5.8
Hz), 4.45 (t, 1H, CHOH, J= 6.6 Hz), 2.88 (q, 2H, NHCH2, J= 6.6
Hz), 2.40 (s, 3H, CH3), 1.85-1.70 (m, 2H, CH2), 1.68 -1.05 (m,
16H, 8 x CH2); 13C NMR (50 MHz, CDCl3): δ 143.4, 136.8,
129.7, 127.0, 120.2, 61.2, 43.1, 35.1, 29.4, 29.1, 29.0, 28.8, 28.7,
26.3, 24.4, 21.5. Anal. Calcd for C19H30N2O3S: C, 62.26; H, 8.25;
N, 7.64. Found: C, 62.19; H, 8.34; N, 7.57.
4.2.9.5.
2-Hydroxy-12-(4-
methylphenylsulfonamido)dodecanamide (20e). Yield 50%;
white solid; mp 101-103 oC; 1H NMR (200 MHz, CDCl3): δ 7.75
(d, 2H, arom, J = 8.4 Hz), 7.30 (d, 2H, arom, J = 8.4 Hz), 6.47
(m, 1H, NHH), 5.81 (m, 1H, CONHH), 4.93 (m, 1H, SO2NH),
4.32-4.05 (m, 1H, CHOH), 3.00-2.82 (m, 2H, NHCH2), 2.49 (bs,
1H, OH), 2.43 (s, 3H, CH3), 2.00-1.58 (m, 4H, 2 x CH2), 1.55-
1.05 (m, 14H, 7 x CH2); 13C NMR (50 MHz, CDCl3): δ 174.2,
143.3, 136.7, 129.8, 127.0, 74.9, 43.1, 35.5, 29.5, 29.4, 29.2,
29.1, 28.0, 26.2, 24.3, 21.4. Anal. Calcd for C19H32N2O4S: C,
59.35; H, 8.39; N, 7.29;. Found: C, 59.27; H, 8.44; N, 7.21.
4.2.9. General method for the synthesis of 2-hydroxy-amides
20a-e
A solution of 2-hydroxy-nitrile 19a-e (1.0 mmol) in conc.
HCl (2.5 mL) was stirred overnight at room temperature. Then,
water was added and the aqueous solution was extracted with
CHCl3 (3 × 15 mL). The combined organic layers were washed
with brine and dried over Na2SO4. The organic solvent was
evaporated under reduced pressure and the resulting 2-hydroxy-
amide was precipitated using Et2O.
4.2.10. General method for the synthesis of 2-hydroxy-acids
21a-e
To a solution of 2-hydroxy-amide 20a-e (1.0 mmol) in a
mixture of EtOH/water (2:1, 10 mL), KOH (0.56 g, 10.0 mmol)
was added and the reaction mixture was refluxed for 4 h. After
cooling, EtOH was removed under reduced pressure, water was
added and the aqueous solution was acidified with conc. H2SO4
until pH 1, followed by extraction with Et2O (3 × 5 mL). The
combined organic layers were washed with brine and dried over
Na2SO4. The organic solvent was evaporated under reduced
4.2.9.1. 6-(4-(Hexyloxy)phenyl)-2-hydroxyhexanamide (20a).
o
1
Yield 80%; white solid; mp 131-133 C; H NMR (200 MHz,
CDCl3): δ 7.07 (d, 2H, arom, J = 8.4 Hz), 6.82 (d, 2H, arom, J =

o
pressure and the residue was purified by recrystallization using
CHCl3/petroleum ether (bp 40-60 °C).
stirred for 1 h at 0 C and overnight at room temperature. The
solvent was evaporated under reduced pressure and EtOAc (20
mL) was added. The organic layer was washed consecutively
with brine, 1 N HCl, brine, 5% NaHCO3, and brine, dried over
Na2SO4 and evaporated under reduced pressure. The residue was
purified by column chromatography using CH2Cl2/MeOH 99:1 as
eluent.
4.2.10.1. 6-(4-(Hexyloxy)phenyl)-2-hydroxyhexanoic acid
o
(21a). Yield 96%; white solid; mp 94-96 C; 1H NMR (200
MHz, CDCl3): δ 7.08 (d, 2H, arom, J = 8.4 Hz), 6.83 (d, 2H,
arom, J = 8.4 Hz), 4.91 (bs, 1H, OH), 4.28 (dd, 1H, CHOH, J1 =
7.2 Hz, J2 = 4.0 Hz), 3.94 (t, 2H, CH2OPh, J = 6.6 Hz), 2.58 (t,
2H, PhCH2, J = 7.4 Hz), 1.98-1.25 (m, 14H, 7 x CH2), 0.92 (t,
3H, CH3, J = 6.6 Hz); 13C NMR (50 MHz, CDCl3): δ 179.8,
157.2, 134.2, 129.2, 114.4, 70.2, 68.1, 34.8, 34.0, 31.6, 31.3,
29.3, 25.7, 24.4, 22.6, 14.0. Anal. Calcd for C18H28O4: C, 70.10;
H, 9.15. Found: C, 70.01; H, 9.26.
4.2.11.1.
Ethyl
4-(6-(4-(hexyloxy)phenyl)-2-
hydroxyhexanamido)butanoate (24a). Yield 70%; white solid;
mp 71-73 C; 1H NMR (200 MHz, CDCl3): δ 7.05 (d, 2H, arom,
o
J = 8.8 Hz), 6.86 (t, 1H, NHCO, J = 8.7 Hz), 6.79 (d, 2H, arom, J
= 8.8 Hz), 4.12 (q, 2H, OCH2CH3, J = 7.2 Hz), 4.04-4.01 (m, 1H,
CHOH), 3.91 (t, 2H, CH2OPh, J = 6.6 Hz), 3.50 (br s, 1H, OH),
3.29 (q, 2H, NHCH2, J = 6.6 Hz), 2.54 (t, 2H, PhCH2, J = 7.4
Hz), 2.33 (t, 2H, CH2COOEt, J = 7.4 Hz), 1.89-1.51 (m, 8H, , 4 x
CH2), 1.50-1.26 (m, 8H, 4 x CH2), 1.25 (t, 3H, CH3, J = 7.2 Hz),
0.90 (t, 3H, CH3, J = 6.6 Hz); 13C NMR (50 MHz, CDCl3): δ
174.3, 173.2, 157.1, 134.2, 129.1, 114.3, 71.9, 67.9, 60.5, 38.4,
34.8, 34.6, 31.6, 31.5, 31.3, 29.2, 25.6, 24.6, 24.5, 22.6, 14.1,
13.9. Anal. Calcd for C24H39NO5: C, 68.38; H, 9.32; N, 3.32.
Found: C, 68.26; H, 9.41; N, 3.25.
4.2.10.2. 2-Hydroxy-5-(4-octylphenoxy)pentanoic acid (21b).
o
1
Yield 92%; white solid; mp 102-104 C; H NMR (200 MHz,
CDCl3): δ 7.10 (d, 2H, arom, J = 8.0 Hz), 6.82 (d, 2H, arom, J =
8.4 Hz), 4.48 (bs, 1H, OH), 4.36 (t, 1H, CHOH, J = 6.6 Hz), 4.00
(t, 2H, PhOCH2, J = 5.6 Hz), 2.55 (t, 2H, CH2Ph, J = 7.4 Hz),
2.14-1.86 (m, 4H, 2 x CH2), 1.71-1.58 (m, 2H, CH2), 1.38-1.15
(m, 10H, 5 x CH2), 0.90 (t, 3H, CH3, J = 7.0 Hz); 13C NMR (50
MHz, CDCl3): δ 179.0, 156.6, 135.4, 129.2, 114.3, 70.0, 67.5,
35.0, 31.9, 31.7, 31.0, 29.5, 29.3, 24.9, 22.6, 14.1. Anal. Calcd
for C19H30O4: C, 70.77; H, 9.38. Found: C, 70.69; H, 9.45.
4.2.11.2.
Ethyl
4-(2-hydroxy-5-(4-
octylphenoxy)pentanamido)butanoate (24b). Yield 81%; white
o
4.2.10.3. 2-Hydroxy-13-phenyltridecanoic acid (21c). Yield
solid; mp 78-80 C; 1H NMR (200 MHz, CDCl3): δ 7.07 (d, 2H,
o
1
98%; white solid; mp 62-64 C; H NMR (200 MHz, CDCl3): δ
7.93-7.21 (m, 5H, Ph), 5.80 (br s, 1H, OH), 4.35 (dd, 1H, CHOH,
J1 = 7.2 Hz, J2 = 4.0 Hz), 2.68 (t, 2H, PhCH2, J= 7.4 Hz), 1.95-
1.79 (m, 2H, CH2CHOH), 1.79-1.55 (m, 2H, CH2), 1.50-1.15 (m,
16H, 8 x CH2); 13C NMR (50 MHz, CDCl3): δ 179.7, 142.9,
128.4, 128.2, 125.5, 70.3, 36.0, 34.2, 31.5, 29.5, 29.4, 29.3, 29.2,
24.7. Anal. Calcd for C19H30O3: C, 74.47; H, 9.87. Found: C,
74.39; H, 9.93.
arom, J = 8.6 Hz), 6.98 (t, 1H, NHCO, J = 5.8 Hz), 6.80 (d, 2H,
arom, J = 8.6 Hz), 4.18-4.06 (m, 3H, CHOH, OCH2CH3), 3.96 (t,
2H, PhOCH2, J = 6.0 Hz), 3.52 (bs, 1H, OH), 3.30 (q, 2H,
CONHCH2, J = 7.0 Hz), 2.52 (t, 2H, CH2Ph, J = 7.4 Hz), 2.34 (t,
2H, CH2COOEt, J = 7.4 Hz), 2.18-1.72 (m, 6H, 3 x CH2), 1.65-
1.47 (m, 2H, CH2), 1.38-1.17 (m, 13H, 5 x CH2, CH3), 0.87 (t,
3H, CH3); 13C NMR (50 MHz, CDCl3): δ 174.0, 173.2, 156.4,
135.4, 129.2, 114.2, 71.7, 67.9, 60.5, 38.4, 34.9, 31.8, 31.6, 31.5,
29.4, 29.2, 25.1, 24.7, 22.6, 14.1, 14.0. Anal. Calcd for
C25H41NO5: C, 68.93; H, 9.49; N, 3.22. Found: C, 68.85; H, 9.56;
N, 3.15.
4.2.10.4. 5-(4-(Hexyloxy)phenoxy)-2-hydroxypentanoic acid
o
1
(21d). Yield 100%; white solid; mp 102-104 C; Η NMR (200
MHz, CDCl3): δ 6.90-6.60 (m, 4H, arom), 4.92 (bs, 1H, OH),
4.30-4.00 (m, 1H, CHOH), 3.85 (t, 2H, OCH2, J = 6.0 Hz), 3.80
(t, 2H, OCH2, J = 6.0 Hz), 2.00-1.50 (m, 6H, 3 x CH2), 1.50-1.10
(m, 6H, 3 x CH2), 0.80 (t, 3H, CH3, J = 6.0 Hz); 13C NMR (50
MHz, CDCl3): δ 176.8, 153.1, 152.7, 115.2, 69.8, 68.5, 68.0,
31.4, 30.6, 29.1, 25.5, 24.8, 22.4, 13.8. Anal. Calcd for C17H26O5:
C, 65.78; H, 8.44. Found: C, 65.52; H, 8.66.
4.2.11.3.
Ethyl
4-(2-hydroxy-12-(4-
(24c).
1
methylphenylsulfonamido)dodecanamido)butanoate
o
Yield 59%; white solid; mp 57-59 C; H NMR (200 MHz,
CDCl3): δ 7.69 (d, 2H, arom, J = 8.0 Hz), 7.25 (d, 2H, arom, J =
8.6 Hz), 6.74 (m, 1H, NHCO), 4.70 (m, 1H, SO2NH), 4.13-4.03
(m, 3H, CHOH, CH2CH3), 3.42 (bs, 1H, OH), 3.27 (q, 2H,
CONHCH2, J = 7.0 Hz), 2.90-2.78 (m, 2H, SO2NHCH2), 2.37 (s,
3H, CH3Ph), 2.30 (t, 2H, CH2COOEt, J = 7.4 Hz), 1.87-1.63 (m,
3H, CH2, CHH), 1.59-1.42 (m, 1H, CHH), 1.40-1.02 (m, 19H, 8
x CH2, CH3); 13C NMR (50 MHz, CDCl3): δ 174.2, 173.4, 143.2,
137.0, 129.6, 127.0, 72.0, 60.6, 43.2, 38.5, 34.8, 31.7, 29.4, 29.1,
28.8, 26.3, 24.8, 24.6, 21.5, 14.1. Anal. Calcd for C25H42N2O6S:
C, 60.21; H, 8.49; N, 5.62. Found: C, 60.13; H, 8.57; N, 5.71.
4.2.10.5.
2-Hydroxy-12-(4-
methylphenylsulfonamido)dodecanoic acid (21e). Yield 82%;
white solid; mp 83-85 oC; 1H NMR (200 MHz, CDCl3): δ 7.70 (d,
2H, arom, J = 8.0 Hz), 7.25 (d, 2H, arom, J = 8.0 Hz), 5.15 (br s,
2H, NH, OH), 4.21 (dd, 1H, CHOH, J1 = 6.6 Hz, J2 = 5.2 Hz),
2.90-2.78 (m, 2H, NHCH2), 2.37 (s, 3H, CH3), 1.80-1.53 (m, 2H,
CH2), 1.44-1.35 (m, 4H, 2 x CH2),1.30-1.15 (m, 12H, 6 x CH2);
13C NMR (50 MHz, CDCl3): δ 178.7, 143.3, 136.7, 129.6, 127.0,
70.2, 43.1, 34.0, 29.5, 29.3, 29.2, 29.0, 28.9, 26.3, 24.5, 21.4.
Anal. Calcd for C19H31NO5S: C, 59.19; H, 8.10; N, 3.63. Found:
C, 59.06; H, 8.21; N, 3.48.
4.2.11.4.
Ethyl
5-(5-(4-(hexyloxy)phenoxy)-2-
hydroxypentanamido)pentanoate (24d). Yield 58%; white
solid; mp 89-91 oC; 1Η NMR (200 MHz, CDCl3): δ 6.90-6.80 (m,
4H, arom), 6.75 (t, 1H, NH, J = 6.0 Hz), 4.30-4.10 (m, 1H,
CHOH), 4.11 (q, 2H, OCH2CH3, J = 6.0 Hz), 3.96 (t, 2H, OCH2,
J = 6.0 Hz), 3.88 (t, 2H, OCH2, J = 6.0 Hz), 3.28 (q, 2H, NHCH2,
J = 6.0 Hz), 2.31 (t, 2H, CH2COO, J = 6.0 Hz), 2.20-1.50 (m,
10H, 5 x CH2), 1.50-1.30 (m, 6H, 3 x CH2), 1.23 (t, 3H, CH3, J =
6.0 Hz), 0.89 (t, 3H, CH3, J = 6.0 Hz); 13C NMR (50 MHz,
CDCl3): δ 173.5, 170.5, 153.7, 152.2, 115.5, 115.4, 71.9, 68.8,
68.6, 60.4, 38.6, 33.7, 32.2, 31.6, 29.3, 29.0, 25.7, 25.3, 22.6,
22.1, 14.2, 14.0. Anal. Calcd for C24H39NO6: C, 65.88; H, 8.98;
N, 3.20. Found: C, 65.62; H, 9.11; N, 3.32.
4.2.11 General method for the coupling of 2-hydroxy-acids
To a stirred solution of the 2-hydroxy-acid 21a-e (1.0 mmol)
and the amine (1.0 mmol) in CH2Cl2 (10 mL), Et3N (0.3 mL, 2.2
mmol in case of hydrochloride salt of the amine or 0.15 mL, 1.1
mmol in case of free amine) and subsequently 1-(3-
dimethylaminopropyl)-3-ethyl
carbodiimide
hydrochloride
(WSCI) (0.21 g, 1.1 mmol) and 1-hydroxybenzotriazole (HOBt)
(0.14 g, 1.0 mmol) were added at 0 oC. The reaction mixture was

Calcd for C23H37NO5: C, 67.78; H, 9.15; N, 3.44. Found: C,
67.65; H, 9.26; N, 3.36.
4.2.11.5.
Ethyl
4-(2-hydroxy-13-
phenyltridecanamido)butanoate (24e). Yield 87%; white solid;
o
1
mp 67-69 C; H NMR (200 MHz, CDCl3): δ 7.39-7.20 (m, 5H,
Ph), 6.86 (t, 1H, NHCO, J = 5.8 Hz), 4.27-4.05 (m, 3H, CHOH,
OCH2CH3), 3.40 (q, 2H, NHCH2, J = 6.6 Hz), 3.22 (d, 1H, OH, J
= 4.8 Hz), 2.68 (t, 2H, PhCH2, J = 7.2 Hz), 2.43 (t, 2H,
CH2COOEt, J = 7.2 Hz), 2.00-1.81 (m, 4H, NHCH2CH2,
CH2CHOH), 1.78-1.58 (m, 4H, 2 x CH2), 1.,56-1.15 (m, 17H, 7x
CH2, CH3); 13C NMR (50 MHz, CDCl3): δ 174.2, 173.3, 142.9,
128.3, 128.1, 125.5, 72.1, 60.6, 38.4, 35.9, 34.9, 31.7, 31.5, 29.5,
29.4, 29.3, 29.2, 25.0, 24.6, 14.1. Anal. Calcd for C25H41NO4: C,
71.56; H, 9.85; N, 3.34. Found: C, 71.44; H, 9.97; N, 3.26.
4.2.12.3.
4-(2-Hydroxy-12-(4-
acid
methylphenylsulfonamido)dodecanamido)butanoic
(26c). Yield 92%; white solid; mp 58-60 oC; 1H NMR (200 MHz,
CDCl3): δ 7.77 (d, 2H, arom, J = 8.0 Hz), 7.41 (d, 2H, arom, J =
8.0 Hz), 6.98 (bs, 1H, NHCO), 4.70 (bs, 1H, SO2NH), 4.04 (dd,
1H, CHOH, J1 = 4.0 Hz, J2 = 7.0 Hz), 3.81 (bs, 1H, OH), 3.31 (t,
2H, CONHCH2, J = 7.0 Hz), 2.86 (t, 2H, SO2NHCH2, J = 7.0
Hz), 2.47 (s, 3H, CH3), 2.38 (t, 2H, CH2COOH, J = 7.4 Hz),
1.92-1.74 (m, 4H, 2 x CH2), 1.71-1.57 (m, 2H, SO2NHCH2CH2),
1.45-1.15 (m, 14H, 7 x CH2); 13C NMR (50 MHz, CDCl3): δ
177.5, 176.9, 144.5, 139.0, 130.7, 128.0, 72.8, 44.0, 39.3, 35.7,
32.1, 30.5, 30.2, 27.6, 26.0, 25.9, 21.5. Anal. Calcd for
C23H38N2O6S: C, 58.70; H, 8.14; N, 5.95. Found: C, 58.63; H,
8.27; N, 5.84.
4.2.11.6.
tert-Butyl
4-(5-(4-(hexyloxy)phenoxy)-2-
hydroxypentanamido)butanoate (30). Yield 72%; yellowish
1
low mp solid; Η NMR (200 MHz, CDCl3): δ 7.01 (t, 1H, NH, J
= 6.0 Hz), 6.90-6.60 (m, 4H, arom), 4.34 (br s, 1H, OH), 4.20-
4.00 (m, 1H, CHOH), 3.89 (t, 2H, OCH2, J = 6.0 Hz), 3.84 (t, 2H,
OCH2, J = 6.0 Hz), 3.25 (q, 2H, NHCH2, J = 6.0 Hz), 2.22 (t, 2H,
CH2COO, J = 6.0 Hz), 2.10-1.60 (m, 8H, 4 x CH2), 1.40 (s, 9H,
(C(CH3)3)), 1.30-1.10 (m, 6H, 3 x CH2), 0.86 (t, 3H, CH3, J = 6.0
Hz); 13C NMR (50 MHz, CDCl3): δ 174.1, 172.6, 153.3, 152.4,
115.3, 115.2, 80.5, 71.6, 68.5, 38.3, 32.7, 31.7, 31.5, 29.2, 27.9,
25.6, 25.1, 24.7, 22.5, 13.9. Anal. Calcd for C25H41NO6: C, 66.49;
H, 9.15; N, 3.10. Found: C, 66.28; H, 9.33; N, 3.24.
4.2.12.4.
5-(5-(4-(Hexyloxy)phenoxy)-2-
hydroxypentanamido)pentanoic acid (26d). Yield 100%; white
o
1
solid; mp 68-70 C; Η NMR (200 MHz, CDCl3 + drops of
CD3OD): δ 7.03 (t, 1H, NH, J = 6.0 Hz), 6.90-6.60 (m, 4H,
arom), 4.20-4.00 (m, 1H, CHOH), 3.92 (t, 2H, OCH2, J = 6.0
Hz), 3.87 (t, 2H, OCH2, J = 6.0 Hz), 3.25 (q, 2H, NHCH2, J = 6.0
Hz), 2.31 (t, 2H, CH2COOΗ, J = 6.0 Hz), 2.10-1.50 (m, 10H, 5 x
CH2), 1.50-1.10 (m, 6H, 3 x CH2), 0.87 (t, 3H, CH3, J = 6.0 Hz);
13C NMR (50 MHz, CDCl3 + drops of CD3OD): δ 176.5, 174.5,
153.4, 152.5, 115.4, 115.3, 71.6, 68.6, 38.4, 33.3, 33.0, 31.5,
29.3, 28.7, 25.7, 25.2, 22.6, 21.8, 14.0. Anal. Calcd for
C22H35NO6: C, 64.52; H, 8.61; N, 3.42. Found: C, 64.29; H, 8.83;
N, 3.55.
4.2.12 General method for the saponification
To a stirred solution of the 2-hydroxyamide ester 24a-d (1.0
mmol) in a mixture of dioxane/H2O (9:1, 10 mL) 1 N NaOH (1.1
mL, 1.1 mmol) was added, and the mixture was stirred for 12 h at
room temperature. The organic solvent was evaporated under
reduced pressure, and H2O (5 mL) was added. The aqueous layer
was washed with EtOAc, acidified with 1 N HCl, and extracted
with EtOAc (3 × 6 mL). The combined organic layers were
washed with brine, dried over Na2SO4, and evaporated under
reduced pressure. The residue was purified by column
chromatography using CHCl3/MeOH 9:1 as eluent or
recrystallized from MeOH/Et2O.
4.2.13 General method for the oxidation of 2-hydroxyamides
To a solution of the 2-hydroxyamides 24a-c, 26a-d or 30 (1
mmol) in dry CH2Cl2 (10 mL) Dess-Martin periodinane (0.64 g,
1.5 mmol) was added and the mixture was stirred for 1 h at room
temperature. The organic solvent was evaporated under reduce
pressure and Et2O (30 mL) was added. The organic phase was
washed with saturated aqueous NaHCO3 (20 mL) containing
Na2S2O3 (1.5 g, 9.5 mmol), H2O (20 mL), dried over Na2SO4, and
the organic solvent was evaporated under reduced pressure. The
residue was purified by column chromatography using petroleum
ether (bp 40-60 °C)/EtOAc as eluent. In the case of 26a-d, after
reaction completion the organic solvent was evaporated and the
residue was purified by column chromatography.
4.2.12.1.
4-(6-(4-(Hexyloxy)phenyl)-2-
hydroxyhexanamido)butanoic acid (26a). Yield 86%; white
solid; 1H NMR (200 MHz, CDCl3): δ 7.18-7.10 (m, 1H, NHCO),
7.05 (d, 2H, arom, J = 8.4 Hz), 6.80 (d, 2H, arom, J = 8.4 Hz),
4.18-4.05 (m, 1H, CHOH), 3.92 (t, 2H, CH2OPh, J = 6.2Hz),
3.47 (bs, 1H, OH), 3.42-3.17 (m, 2H, CONHCH2), 2.54 (t, 2H,
PhCH2, J = 7.4 Hz), 2.36 (t, 2H, CH2COOH, J = 6.6 Hz), 1.85-
1.20 (m, 16H, 8 x CH2), 0.91 (t, 3H, CH3, J = 6.6 Hz); 13C NMR
(50 MHz, CDCl3): δ 177.2, 175.4, 157.2, 134.3, 129.2, 114.3,
72.0, 68.0, 38.4, 34.8, 34.4, 31.6, 31.3, 29.3, 25.7, 24.7, 24.5,
22.6, 14.0. Anal. Calcd for C22H35NO5: C, 67.15; H, 8.96; N,
3.56. Found: C, 67.01; H, 9.10; N, 3.47.
4.2.13.1.
Ethyl
4-(6-(4-(hexyloxy)phenyl)-2-
oxohexanamido)butanoate (25a). Yield 88%; white solid; mp
o
1
56-58 C; H NMR (200 MHz, CDCl3): δ 7.40-70.35 (m, 1H,
NHCOCO), 7.29 (d, 2H, arom, J = 8.4 Hz), 7.03 (d, 2H, arom, J
= 8.4 Hz), 4.36 (q, 2H, OCH2CH3, J = 7.4 Hz), 4.14 (t, 2H,
CH2OPh, J = 6.6Hz), 3.57 (q, 2H, NHCH2, J = 7.0 Hz), 3.16 (t,
2H, CH2, J = 6.6 Hz), 2.79 (t, 2H, PhCH2, J = 8.0 Hz), 2.59 (t,
2H, CH2COOEt, J = 7.4 Hz), 2.18-1.19 (m, 4H, 2 x CH2), 1.87-
1.74 (m, 4H, 2 x CH2), 1.70-1.53 (m, 6H, 3 x CH2), 1.48 (t, 3H,
CH3, J = 7.4 Hz), 1.13 (t, 3H, CH3, J = 6.2 Hz); 13C NMR (50
MHz, CDCl3): δ 198.9, 172.9, 160.2, 157.2, 133.8, 129.1, 114.3,
67.9, 60.5, 38.6, 36.5, 34.6, 31.5, 30.9, 29.2, 25.7, 24.3, 22.6,
22.5, 14.1, 14.0. Anal. Calcd for C24H37NO5: C, 68.71; H, 8.89;
N, 3.34. Found: C, 68.64; H, 8.97; N, 3.45.
4.2.12.2.
4-(2-Hydroxy-5-(4-
octylphenoxy)pentanamido)butanoic acid (26b). Yield 97%;
o
white solid; mp 111-113 C; 1H NMR (200 MHz, CDCl3): δ
7.21-7.12 (m, 1H, NHCO), 7.08 (d, 2H, arom, J = 8.4 Hz), 6.84
(d, 2H, arom, J = 8.4 Hz), 4.11 (dd, 1H, CHOH, J1 = 3.4 Hz, J2 =
7.4 Hz), 4.00 (t, 2H, PhOCH2, J = 5.8 Hz), 3.56 (bs, 1H, OH),
3.32 (m, 2H, NHCH2, J = 7.0 Hz), 2.56 (t, 2H, CH2Ph, J = 7.4
Hz), 2.37 (t, 2H, CH2COOH, J = 7.4 Hz), 2.02-1.75 (m, 6H, 3 x
CH2), 1.65-1.45 (m, 2H, CH2), 1.42-1.21 (m, 10H, 5 x CH2), 0.93
(t, 3H, CH3, J = 6.2 Hz); 13C NMR (50 MHz, CDCl3): δ 177.2,
176.9, 158.5, 136.0, 130.2, 115.4, 72.6, 68.8, 39.3, 36.0, 33.0,
32.9, 32.4, 32.2, 30.6, 30.4, 30.3, 26.2, 25.9, 23.7, 14.4. Anal.
4.2.13.2.
Ethyl
4-(5-(4-octylphenoxy)-2-
oxopentanamido)butanoate (25b). Yield 60%; white solid; mp
49-51oC; H NMR (200 MHz, CDCl3): δ 7.22-7.15 (br s 1H,
1
NHCOCO), 7.06 (d, 2H, arom, J = 8.8 Hz), 6.77 (d, 2H, arom, J
= 8.4 Hz), 4.14 (q, 2H, OCH2CH3, J = 7.4 Hz), 3.97 (t, 2H,

CH2OPh, J = 6.2 Hz), 3.34 (q, 2H, NHCH2, J = 6.6Hz), 3.12 (t,
2H, CH2COCO, J = 7.0 Hz), 2.53 (t, 2H, CH2Ph, J = 7.4 Hz),
2.36 (t, 2H, CH2COOEt, J = 7.2 Hz), 2.15-2.05 (m, 2H, CH2),
1.98-1.79 (m, 2H, CH2), 1.65-1.48 (m, 2H, CH2), 1.29-1.15 (m,
13H, 5 x CH2, CH3), 0.88 (t, 3H, CH3, J = 6.2 Hz); 13C NMR (50
MHz, CDCl3): δ 198.5, 172.9, 160.2, 156.6, 135.1, 129.1, 114.2,
66.5, 60.5, 38.7, 35.0, 33.5, 31.8, 31.7, 31.5, 29.4, 29.2, 24.3,
23.3, 22.6, 14.1, 14.0. Anal. Calcd for C25H39NO5: C, 69.25; H,
9.07; N, 3.23. Found: C, 69.11; H, 9.20; N, 3.17.
4.2.13.7.
5-(5-(4-(Hexyloxy)phenoxy)-2-
oxopentanamido)pentanoic acid (27d). Yield 76%; white solid;
mp 91-93 oC; 1Η NMR (200 MHz, DMSO): δ 8.61 (t, 1H, NH, J
= 6.0 Hz), 7.00-6.60 (m, 4H, arom), 3.88 (t, 2H, OCH2, J = 6.0
Hz), 3.86 (t, 2H, OCH2, J = 6.0 Hz), 3.09 (q, 2H, NHCH2, J = 6.0
Hz), 2.94 (t, 2H, CH2COCO, J = 6.0 Hz), 2.20 (t, 2H,
CH2COOH, J = 6.0 Hz), 1.92 (quintet, 2H, CH2, J = 6.0 Hz), 1.65
(quintet, 2H, CH2, J = 6.0 Hz), 1.50-1.40 (m, 4H, 2 x CH2), 1.40-
1.20 (m, 6H, 3 x CH2), 0.86 (t, 3H, CH3, J = 6.0 Hz); 13C NMR
(50 MHz, DMSO): δ 198.9, 176.5, 161.2, 152.8, 152.4, 115.4,
67.9, 67.1, 40.6, 33.7, 33.4, 31.1, 28.9, 28.3, 25.3, 23.1, 22.2,
22.0, 14.1. Anal. Calcd for C22H33NO6: C, 64.84; H, 8.16; N,
3.44. Found: C, 64.56; H, 8.35; N, 3.51.
4.2.13.3.
Ethyl
4-(12-(4-methylphenylsulfonamido)-2-
oxododecanamido)butanoate (25c). Yield 73%; white solid; mp
105-107oC; 1H NMR (200 MHz, CDCl3): δ 7.74 (d, 2H, arom, J
= 8.0 Hz), 7.29 (d, 2H, arom, J = 8.4 Hz), 7.21-7.12 (m, 1H,
COCONH), 4.74 (t, 1H, SO2NH, J = 5.8 Hz), 4.12 (q, 2H,
CH2CH3, J = 6.6 Hz), 3.34 (q, 2H, CONHCH2, J = 6.6 Hz), 2.95-
2.82 (m, 4H, SO2NHCH2, CH2COCO), 2.41 (S, 3H, CH3Ph), 2.34
(t, 2H, CH2, J = 7.2 Hz), 1.94-1.80 (m, 2H, CH2), 1.62-1.50 (m,
2H, CH2), 1.50-1.35 (m, 2H, CH2), 1.35-1.10 (m, 15H, 6 x CH2,
CH3); 13C NMR (50 MHz, CDCl3): δ 199.2, 172.9, 160.3, 143.2,
137.0, 129.6, 127.0, 60.5, 43.1, 38.6, 36.6, 31.5, 29.4, 29.2, 29.1,
28.9, 26.4, 24.3, 23.0, 21.4, 14.1. Anal. Calcd for C25H40N2O6S:
C, 60.46; H, 8.12; N, 5.64. Found: C, 60.32; H, 8.26; N, 5.52.
4.2.13.8.
tert-Butyl
4-(5-(4-(hexyloxy)phenoxy)-2-
oxopentanamido)butanoate (31). Yield 84%; yellowish solid;
mp 55-57 oC; 1Η NMR (200 MHz, CDCl3): δ 7.20 (t, 1H, NH, J =
6.0 Hz), 7.00-6.60 (m, 4H, arom), 3.89 (t, 2H, OCH2, J = 6.0 Hz),
3.84 (t, 2H, OCH2, J = 6.0 Hz), 3.28 (q, 2H, NHCH2, J = 6.0 Hz),
3.07 (t, 2H, CH2COCO, J = 6.0 Hz), 2.23 (t, 2H, CH2COO, J =
6.0 Hz), 2.03 (quintet, 2H, CH2, J = 6.0 Hz), 1.88 (quintet, 2H,
CH2, J = 6.0 Hz), 1.79 (quintet, 2H, CH2, J = 6.0 Hz), 1.70-1.60
(m, 2H, CH2), 1.40 (s, 9H, (C(CH3)3)), 1.30-1.10 (m, 4H, 2 x
CH2), 0.86 (t, 3H, CH3, J = 6.0 Hz); 13C NMR (50 MHz, CDCl3):
δ 198.4, 172.1, 160.1, 153.2, 152.5, 115.2, 80.4, 68.4, 67.0, 38.6,
33.5, 32.6, 31.4, 29.2, 27.9, 25.6, 24.3, 23.3, 22.5, 13.9. Anal.
Calcd for C25H39NO6: C, 66.79; H, 8.74; N, 3.12. Found: C,
66.60; H, 8.86; N, 3.22.
4.2.13.4.
4-(6-(4-(Hexyloxy)phenyl)-2-
oxohexanamido)butanoic acid (27a). Yield 44%; white solid;
o
1
mp 73-75 C; H NMR (200 MHz, CDCl3): δ 7.21-7.14 (m, 1H,
NHCOCO), 7.07 (d, 2H, arom, J = 8.4 Hz), 6.81 (d, 2H, arom, J
= 8.4 Hz), 3.93 (t, 2H, CH2OPh, J = 6.6 Hz), 3.38 (q, 2H,
CONHCH2, J = 6.6 Hz), 2.94 (t, 2H, CH2COCO, J = 6.6 Hz),
2.57 (t, 2H, PhCH2, J = 6.6 Hz), 2.42 (t, 2H, CH2COOH, , J = 7.4
Hz), 1.94-1.83 (m, 2H, CH2), 1.80-1.70 (m, 2H, CH2), 1.63-1.43
(m, 4H, 2 x CH2), 1.43-1.10 (m, 6H, 3 x CH2), 0.91 (t, 3H, CH3, J
= 6.2 Hz); 13C NMR (50 MHz, CDCl3): δ 198.9, 178.0, 160.4,
157.3, 133.9, 129.2, 114.4, 68.0, 38.6, 36.6, 34.6, 31.6, 31.1,
31.0, 29.3, 25.7, 24.2, 22.7, 22.6, 14.0. Anal. Calcd for
C22H33NO5: C, 67.49; H, 8.50; N, 3.58. Found: C, 67.35; H, 8.62;
N, 3.44.
4.2.14.
14-(4-Ethoxy-4-oxobutylamino)-13,14-
dioxotetradecanoic acid (28)
To a solution of 24e (1.0 mmol) in a mixture of
CCl4/MeCN/H2O (1:1:2, 30 ml), NaIO4 (6.2 g, 29.0 mmol) and
RuCl3.6H2O (12 mg, 0.045 mmol) were added and the mixture
was stirred overnight at room temperature. Dichloromethane (30
ml) was added and, after stirring for 10 min, the organic layer
was separated, dried over Na2SO4 and concentrated under
reduced pressure. The residue was purified by column
chromatography using petroleum ether (bp 40-60 °C)/EtOAc 1:1
as eluent. Yield 25%; white solid; mp 77-79 C; H NMR (200
MHz, CDCl3): δ 7.18-7.08 (m, 1H, NHCOCO), 4.20-4.09 (q, 2H,
OHCH2CH3, J = 6.8 Hz), 3.35 (q, 2H, NHCH2, J = 6.8 Hz), 2.91
(t, 2H, CH2COCO, J = 7.2 Hz), 2.39-2.31 (m, 4H, CH2COOEt,
CH2COOH), 2.00-1.80 (m, 2H, NHCH2CH2), 1.75-1.50 (m, 4H,
2 x CH2), 1.40-1.10 (m, 17H, 7 x CH2, CH3); 13C; NMR (50
MHz, CDCl3): δ 199.2, 179.1, 173.0, 160.3, 60.6, 38.7, 36.7,
33.9, 31.6, 29.7, 29.4, 29.3, 29.2, 29.1, 29.0, 24.6, 24.4, 23.1,
14.2. Anal. Calcd for C20H35NO6: C, 62.31; H, 9.15; N, 3.63.
Found: C, 62.25; H, 9.23; N, 3.57.
4.2.13.5. 4-(5-(4-Octylphenoxy)-2-oxopentanamido)butanoic
acid (27b). Yield 60%; white solid; mp 49-51 oC; 1H NMR (200
MHz, CDCl3): δ 7.32-7.20 (m, 1H, NHCOCO), 7.16 (d, 2H,
arom, J = 8.4 Hz), 6.87 (d, 2H, arom, J = 8.4 Hz), 4.07 (t, 2H,
PhOCH2, J = 7.5 Hz), 3.47 (q, 2H, NHCH2, J = 6.6 Hz), 3.22 (t,
2H, CH2COCO, J = 7.0 Hz), 2.62 (t, 2H, PhCH2, J = 7.4 Hz),
2.51 (t, 2H, CH2COOH, J = 7.0 Hz), 2.25-2.08 (m, 2H, CH2),
2.08-1.90 (m, 2H, CH2), 1.75-1.58 (m, 2H, CH2), 1.45-1.23 (m,
10 H, 5 x CH2), 0.98 (t, 3H, CH3, J = 7.0 Hz); 13C NMR (50
MHz, CDCl3): δ 198.5, 178.1, 160.3, 156.6, 135.3, 129.2, 114.2,
66.6, 38.6, 35.0, 33.6, 31.9, 31.7, 31.2, 29.5, 29.3, 24.2, 23.4,
22.6, 14.1. Anal. Calcd for C23H35NO5: C, 68.12; H, 8.70; N,
3.45. Found: C, 68.03; H, 8.85; N, 3.27.
o
1
4.2.15.
4-(5-(4-(Ηexyloxy)phenoxy)-2-
4.2.13.6.
4-(12-(4-Methylphenylsulfonamido)-2-
oxopentanamido)butanoic acid (32)
oxododecanamido)butanoic acid (27c). Yield 55%; white solid;
A solution of the tert-butyl ester derivative 31 (450 mg, 1 mmol)
in 50% TFA/CH2Cl2 (2 mL) was stirred for 1 h at room
temperature. The organic solvent was evaporated under reduced
pressure and the residue was purified by recrystallization
[EtOAc/petroleum ether (bp 40–60 oC)]. Yield 76%; white solid;
mp 109-111 oC; 1Η NMR (200 MHz, CDCl3): δ 7.16 (t, 1H, NH,
J = 6.0 Hz), 7.00-6.60 (m, 4H, arom), 3.93 (t, 2H, OCH2, J = 6.0
Hz), 3.88 (t, 2H, OCH2, J = 6.0 Hz), 3.36 (q, 2H, NHCH2, J = 6.0
Hz), 3.10 (t, 2H, CH2COCO, J = 6.0 Hz), 2.40 (t, 2H,
CH2COOH, J = 6.0 Hz), 2.08 (quintet, 2H, CH2, J = 6.0 Hz), 1.88
(quintet, 2H, CH2, J = 6.0 Hz), 1.73 (quintet, 2H, CH2, J = 6.0
Hz), 1.50-1.00 (m, 6H, 3 x CH2), 0.89 (t, 3H, CH3, J = 6.0 Hz);
o
1
mp 98-100 C; H NMR (200 MHz, CD3OD): δ 7.46 (d, 2H,
arom, J = 8.2 Hz), 7.11 (d, 2H, arom, J = 8.2 Hz), 3.12-2.95 (m,
2H, CONHCH2), 2.61-2.52 (m, 4H, SO2NHCH2, CH2COCO),
2.16 (s, 3H, CH3), 2.07 (t, 2H, CH2COOH, J = 7.2 Hz), 1.60-1.43
(m, 2H, CH2CH2COOH), 1.38-1.22 (m, 2H, SO2NHCH2CH2),
1.20-0.80 (m, 14H, 7 x CH2); 13C NMR (50 MHz, aceton-d6): δ
199.4, 174.0, 161.4, 143.2, 137.0, 130.0, 127.4, 43.5, 38.7, 36.9,
31.1, 30.6, 30.2, 29.8, 29.7, 29.5, 28.3, 26.8, 24.9, 23.5, 21.0.
Anal. Calcd for C23H36N2O6S: C, 58.95; H, 7.74; N, 5.98. Found:
C, 58.87; H, 7.82; N, 5.87.

13C NMR (50 MHz, CDCl3): δ 198.5, 178.0, 160.3, 153.4, 152.6,
115.4, 68.6, 67.2, 38.6, 33.6, 31.6, 31.1, 29.3, 25.7, 24.2, 23.4,
22.6, 14.0. Anal. Calcd for C21H31NO6: C, 64.10; H, 7.94; N,
3.56. Found: C, 63.91; H, 8.10; N, 3.70.
9. McKew, J. C.; Lee, K. L.; Shen, M. W. H.; Thakker, P.; Foley, M. A.;
Behnke, M. L.; Hu, B.; Sum, F. W.; Tam, S.; Hu, Y.; Chen, L.;
Kirincich, S. J.; Michalak, R.; Thomason, J.; Ipek, M.; Wu, K.; Wooder,
L.; Ramarao, M. K.; Murphy, E. A.; Goodwin, D. G.; Albert, L.; Xu, X.;
Donahue, F.; Ku, M. S.; Keith, J.; Nickerson-Nutter, C. L.; Abraham, W.
M.; Williams, C.; Hegen, M.; Clark, J. D. J. Med. Chem. 2008, 51, 3388.
10. Lee, K. L.; Behnke, M. L.; Foley, M. A.; Chen, L.; Wang, W.; Vargas,
R.; Nunez, J.; Tam, S.; Mollova, N.; Xu, X.; Shen, M. W. H.; Ramarao,
M. K.; Goodwin, D. G.; Nickerson-Nutter, C. L.; Abraham, W. M.;
Williams, C.; Clark, J. D.; McKew, J. C. Bioorg. Med. Chem. 2008, 16,
1345.
4.3. In vitro PLA2 assays
All synthesized inhibitors were tested for inhibition of human
GIVA cPLA2, GVIA iPLA2 and GV sPLA2 using previously
described mixed micelle-based assays.24-26 The buffer and
substrate conditions were optimized for each enzyme assay as
follows: (i) GIVA cPLA2 substrate mixed-micelles were
composed of 400 μM Triton X-100, 97 μM PAPC, 1.8 μM 14C-
labeled PAPC, and 3 μM PIP2 in 100 mM HEPES buffer, pH 7.5,
with 90 μM CaCl2, 2 mM DTT, and 0.1 mg/ml BSA; (ii) GVIA
iPLA2 substrate mixed-micelles were composed of 400 μM
Triton X-100, 98.3 μM PAPC, and 1.7 μM 14C-labeled PAPC in
buffer containing 100 mM HEPES, pH 7.5, 2 mM ATP, and 4
mM DTT; (iii) GV sPLA2 substrate mixed-micelles were
composed of 400 μM Triton X-100, 98.3 μM PAPC, and 1.7 μM
14C-labeled PAPC in buffer containing 50 mM Tris, pH 8.0, and
5 mM CaCl2.
Initial screening of compounds at 0.091 mole fraction
inhibitor in mixed-micelles was carried out. Compounds
displaying 25% or less inhibition of the assays were considered
to have no inhibitory affect (designated N.D.). We report average
percent inhibition for compounds displaying less than 85%
enzyme inhibition. If the percent inhibition was greater than
85%, we determined its XI(50) by plotting percent inhibition
versus inhibitor mole fraction. Inhibition curves were modeled in
Graphpad Prism 5.0 using nonlinear regression targeted at
symmetrical sigmoidal curves based on plots of % inhibition
versus log(inhibitor concentration), to calculate the reported
XI(50) and associated error values.
11. Seno, K.; Okuno, T.; Nishi, K.; Murakami, Y.; Yamada, K.; Nakamoto,
S.; Ono, T. Bioorg. Med. Chem. Lett. 2001, 11, 587.
12. Ono, T.; Yamada, K.; Chikazawa, Y.; Ueno, M.; Nakamoto, S.; Okuno,
T.; Seno, K. Biochem. J. 2002, 363, 727.
13. Seno, K.; Okuno, T.; Nishi, K.; Murakami, Y.; Watanabe, F.; Matsuura,
T.; Wada, M.; Fujii, Y.; Yamada, M.; Ogawa, T.; Okada, T.; Hashizume,
H.; Kii, M.; Hara, S.; Hagishita, S.; Nakamoto, S.; Yamada, K.;
Chikazawa, Y.; Ueno, M.; Teshirogi, I.; Ono, T.; Ohtani, M. J. Med.
Chem. 2000, 43, 1041.
14. Tai, N.; Kuwabara, K.; Kobayashi, M.; Yamada, K.; Ono, T.; Seno, K.;
Gahara, Y.; Ishizaki, J.; Hori, Y. Inflammation Res. 2010, 59, 53.
15. Connolly, S.; Bennion, C.; Botterell, S.; Croshaw, P. J.; Hallam, C.;
Hardy, K.; Hartopp, P.; Jackson, C. G.; King , S. J.; Lawrence, L.;
Mete, A.; Murray, D.; Robinson, D. H.; Smith, G. M.; Stein, L.;
Walters, I.; Wells, E.; Withnall, W. J. J. Med. Chem. 2002, 45, 1348.
16. Walters, I.; Bennion, C.; Connolly, S.; Croshaw, P. J.; Hardy, K.;
Hartopp, P.; Jackson, C. G.; King, S.J.; Lawrence, L.; Mete, A.;
Murray, D.; Robinson, D.H.; Stein, L.; Wells, E.; John Withnall, W.
Bioorg. Med. Chem. Lett. 2004, 14, 3645.
17. Ludwig, J.; Bovens, S.; Brauch, C.; Elfringhoff, A. S.; Lehr, M. J.Med.
Chem. 2006, 49, 2611.
18. Hess, M.; Schulze Elfringhoff, A.; Lehr, M. Bioorg. Med. Chem. 2007,
15, 2883.
19. Fritsche, A.; Elfringhoff, A. S.; Fabian, J.; Lehr, M. Bioorg. Med.
Chem. 2008, 16, 3489.
20. Bovens, S.; Kaptur, M.; Elfringhoff, A. S.; Lehr, M. Bioorg. Med.
Chem. Letters 2009, 19, 2107.
21. Forster, L.; Ludwig, J.; Kaptur, M.; Bovens, S.; Elfringhoff, A. S.;
Holtfrerich, A.; Lehr, M. Bioorg. Med. Chem .2010, 18, 945.
22. Drews, A.; Bovens, S.; Roebrock, K.; Sunderkotter, C.; Reinhardt, D.;
Schafers, M.; Van Der Velde, A.; Schulze Elfringhoff, A.; Fabian, J.;
Lehr, M. J. Med. Chem. 2010, 53, 5165.
Acknowledgments
23. Kokotos, G.; Kotsovolou, S.; Six, D. A.; Constantinou-Kokotou, V.;
Beltzner, C. C.; Dennis, E. A. J. Med. Chem. 2002, 45, 2891.
24. Kokotos, G.; Six, D. A.; Loukas, V.; Smith, T.; Constantinou-Kokotou,
V.; Hadjipavlou-Litina, D.; Kotsovolou, S.; Chiou, A.; Beltzner, C. C.;
Dennis, E. A. J. Med. Chem. 2004, 47, 3615.
25. Stephens, D.; Barbayianni, E.; Constantinou-Kokotou, V.; Peristeraki,
A.; Six, D. A.; Cooper, J.; Harkewicz, R.; Deems, R. A.; Dennis, E. A.;
Kokotos, G. J. Med. Chem. 2006, 49, 2821.
26. Six, D. A.; Barbayianni, E.; Loukas, V.; Constantinou-Kokotou, V.;
Hadjipavlou-Litina, D.; Stephens, D.; Wong, A. C.; Magrioti, V.;
Moutevelis-Minakakis, P.; Baker, S. F.; Dennis, E. A.; Kokotos, G. J.
Med. Chem. 2007, 50, 4222.
This research has been co-financed by the European
Union (European Regional Development Fund-ERDF) and Greek
national
funds
through
the
Operational
Program
“Competitiveness and Entrepreneurship” of the National
Strategic Reference Framework (NSRF) - Research Funding
Program: “Phospholipases A2 inhibitors: Developing a drug
pipeline for the treatment of inflammatory neurological
disorders” (G.K.) and in part by NIH grant RO1 20,501-40
(E.A.D.).
27. Barbayianni, E.; Stephens, D.; Grkovich, A.; Magrioti, V.; Hsu, Y. H.;
Dolatzas, P.; Kalogiannidis, D.; Dennis, E. A.; Kokotos, G. Bioorg.
Med. Chem. 2009, 17, 4833.
28. Yaksh, T. L.; Kokotos, G.; Svensson, C. I.; Stephens, D.; Kokotos, C.
G.; Fitzsimmons, B.; Hadjipavlou-Litina, D.; Hua, X. Y.; Dennis, E. A.
J. Pharmacol. Exp. Therap. 2006, 316, 466.
29. Walters, I.; Bennion, C.; Connolly, S.; Croshaw, P. J.; Hardy,
K.;Hartopp, P.; Jackson, C. G.; King, S. J.; Lawrence, L.; Mete, A.;
Murray, D.; Robinson, D. H.; Stein, L.; Wells, E.; Withnall, W. J.
Bioorg. Med. Chem. Lett. 2004, 14, 3645.
30. Chen, L.; Wang, W.; Lee, K. L.; Shen, M. W.; Murphy, E. A.; Zhang,
W.; Xu, X.; Tam, S.; Nickerson-Nutter, C.; Goodwin, D. G.; Clark, J.
D.; McKew, J. C. J. Med. Chem. 2009, 52, 1156.
31. Kirincich, S. J.; Xiang, J.; Green, N.; Tam, S.; Yang, H. Y.; Shim, J.;
Shen, M. W.; Clark, J. D.; McKew, J. C. Bioorg. Med. Chem. 2009, 17,
4383.
32. Mouchlis, V. D.; Bucher, D.; McCammon, J. A.; Dennis, E. A. PNAS
2015, 112, E516.
33. Mouchlis, V.D.; Dennis, E. A. Adv. Biol. Regul. 2016, 61, 17.
34. Lipinski, C.; Lombardo, F.; Dominy, B.; Feeney, P. Adv. Drug Deliv.
Rev. 1997, 23, 3.
35. Baskakis, C.; Magrioti, V.; Cotton, N.; Stephens, D.; Constantinou-
Kokotou, V.; Dennis, E. A.; Kokotos, G. J. Med. Chem. 2008, 51, 8027.
References
1. Leslie, C. C. J. Lipid Res. 2015, 56, 1386.
2. Dennis, E.A.; Cao, J.; Hsu, Y.-H.; Magrioti, V.; Kokotos, G. Chem. Rev.
2011, 111, 6130.
3. Magrioti, V.; Kokotos, G. Expert Opin. Ther. Pat. 2010, 20, 1.
4. Magrioti, V.; Kokotos, G. Expert Opin. Ther. Pat. 2013, 23, 1123.
5. Street, I. P.; Lin, H. K.; Laliberte, F.; Ghomashchi, F.; Wang, Z.; Perrier,
H.; Tremblay, N. M.; Huang, Z.; Weech, P. K.; Gelb, M. H. Biochemistry
1993, 32, 5935.
6. McKew, J. C.; Lovering, F.; Clark, J. D.; Bemis, J.; Xiang, Y.; Shen, M.;
Zhang, W.; Alvarez, J. C.; Joseph-McCarthy, D. Bioorg. Med. Chem.
Lett. 2003, 13, 4501.
7. McKew, J. C.; Foley, M. A.; Thakker, P.; Behnke, M. L.; Lovering, F.
E.; Sum, F. W.; Tam, S.; Wu, K.; Shen, M. W. H.; Zhang, W.; Gonzalez,
M.; Liu, S.; Mahadevan, A.; Sard, H.; Khor, S. P.; Clark, J. D. J. Med.
Chem. 2006, 49, 135.
8. Lee, K. L.; Foley, M. A.; Chen, L.; Behnke, M. L.; Lovering, F. E.;
Kirincich, S. J.; Wang, W.; Shim, J.; Tam, S.; Shen, M. W. H.; Khor, S.;
Xu, X.; Goodwin, D. G.; Ramarao, M. K.; Nickerson-Nutter, C.;
Donahue, F.; Ku, M. S.; Clark, J. D.; McKew, J. C. J. Med. Chem. 2007,
50, 1380.

36. Kokotos, G.; Hsu, Y. H.; Burke, J. E.; Baskakis, C.; Kokotos, C. G.;
Magrioti, V.; Dennis, E. A. J. Med. Chem. 2010, 53, 3602.
37. Kokotos, G. Synthesis 1990, 299.
38. Nunez, M. T.; Martin, V. S. J. Org. Chem. 1990, 55, 1928.
39. Moutevelis-Minakakis, P.; Sinanoglou, C.; Loukas, V.; Kokotos, G.
Synthesis 2005, 933.
40. Barbayianni, E.; Antonopoulou, G.; Kokotos, G. Pure Appl. Chem.
2012, 84, 1877.