Effect of 6-Benzoyl-benzothiazol-2-one scaffold on the pharmacological profile of α-alkoxyphenylpropionic acid derived PPAR agonists

Article abstract of DOI:10.1080/14756366.2020.1713771

A series of nitrogen heterocycles containing α–ethoxyphenylpropionic acid derivatives were designed as dual PPARα/γ agonist ligands for the treatment of type 2 diabetes (T2D) and its complications. 6-Benzoyl-benzothiazol-2-one was the most tolerant of the

Full text of DOI:10.1080/14756366.2020.1713771

Journal of Enzyme Inhibition and Medicinal Chemistry
ISSN: 1475-6366 (Print) 1475-6374 (Online) Journal homepage: https://www.tandfonline.com/loi/ienz20
Effect of 6-Benzoyl-benzothiazol-2-one
scaffold on the pharmacological profile of α-
alkoxyphenylpropionic acid derived PPAR agonists
Aurélie Hurtevent, Morgan Le Naour, Veronique Leclerc, Pascal Carato,
Patricia Melnyk, Nathalie Hennuyer, Bart Staels, Monique Beucher-Gaudin,
Daniel-Henri Caignard, Catherine Dacquet & Nicolas Lebegue
To cite this article: Aurélie Hurtevent, Morgan Le Naour, Veronique Leclerc, Pascal Carato,
Patricia Melnyk, Nathalie Hennuyer, Bart Staels, Monique Beucher-Gaudin, Daniel-Henri Caignard,
Catherine Dacquet & Nicolas Lebegue (2020) Effect of 6-Benzoyl-benzothiazol-2-one scaffold on
the pharmacological profile of α-alkoxyphenylpropionic acid derived PPAR agonists, Journal of
Enzyme Inhibition and Medicinal Chemistry, 35:1, 524-538, DOI: 10.1080/14756366.2020.1713771
To link to this article: https://doi.org/10.1080/14756366.2020.1713771
© 2020 The Author(s). Published by Informa
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JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY
2020, VOL. 35, NO. 1, 524–538
https://doi.org/10.1080/14756366.2020.1713771
ARTICLE
Effect of 6-Benzoyl-benzothiazol-2-one scaffold on the pharmacological profile of
a-alkoxyphenylpropionic acid derived PPAR agonists
a
a
a
b
a
c
ꢀ
Aurelie Hurtevent , Morgan Le Naour , Veronique Leclerc , Pascal Carato , Patricia Melnyk , Nathalie Hennuyer ,
Bart Staelsc, Monique Beucher-Gaudind, Daniel-Henri Caignarde, Catherine Dacquetd and Nicolas Lebeguea
aUniv. Lille, Inserm, CHU Lille, UMR-S 1172 - JPArc - Centre de Recherche Jean-Pierre AUBERT Neurosciences et Cancer, Lille, France;
b
c
ꢀ
ꢀ
Universite de Poitiers, CIC INSERM 1402, UFR de Medecine et de Pharmacie, Poitiers, France; Univ. Lille, Inserm, CHU Lille, Institut Pasteur de
d
^
ꢀ
ꢀ
Lille, U1011- EGID, Lille, France; Pole d’innovation Therapeutique Maladies Metaboliques, Institut de Recherches Servier, Suresnes, France;
e
^
ꢀ
Pole d’Expertise Chimie Therapeutique, Institut de Recherches Servier, Croissy-sur seine, France
ABSTRACT
ARTICLE HISTORY
Received 21 October 2019
Revised 22 November 2019
Accepted 5 January 2020
A series of nitrogen heterocycles containing a–ethoxyphenylpropionic acid derivatives were designed as
dual PPARa/c agonist ligands for the treatment of type 2 diabetes (T2D) and its complications. 6-Benzoyl-
benzothiazol-2-one was the most tolerant of the tested heterocycles in which incorporation of O-methyl
oxime ether and trifluoroethoxy group followed by enantiomeric resolution led to the (S)-stereoisomer
44b displaying the best in vitro pharmacological profile. Compound 44 b acted as a very potent full
PPARc agonist and a weak partial agonist on the PPARa receptor subtype. Compound 44 b showed high
efficacy in an ob/ob mice model with significant decreases in serum triglyceride, glucose and insulin levels
but mostly with limited body-weight gain and could be considered as a selective PPARc modula-
tor (SPPARcM).
KEYWORDS
Type 2 diabetes; PPAR;
SPPARcM; benzothiazol-2-
one; body weight gain
1. Introduction
found that many of them were full dual PPARa/c agonists with
higher selectivity for the PPARc receptor15. Oxime ether introduc-
tion and enantiomeric resolution within this series of compounds
allowed adjustment of the PPARa/c potency ratio leading to best
equally balanced PPARa/c ligands. Unfortunately, despite high effi-
cacy in an ob/ob mice model of T2D and dyslipidemia, similar to
rosiglitazone and tesaglitazar, these compounds exhibited a disap-
proving benefit–risk ratio as they displayed a significant increase
in body weight gain.
Herein we investigated the impact of the indole core replace-
ment by various nitrogen heterocycles as benzothiazol-2-one, ben-
zothia- or benzoxazin-3-one and 1,3-dihydro-2H-indol-2-one on
PPARc binding affinity and PPARa/c transactivation assays
(Figure 1). The best heterocycle derivative was then selected to
further chemical modulations as introduction of oxime and tri-
fluoroethoxy groups as well as synthesis of optically pure enan-
tiomers which were subjected to in vivo studies to assess their
anti-hyperlipidemic, anti-hyperglycemic, and body weight effects
in experimental animal models.
Type 2 diabetes (T2D), is a metabolic disorder characterised by
hyperglycaemia caused not only by impaired insulin secretion
from the pancreas but also by the increased insulin resistance of
peripheral tissues1,2. The peroxisome proliferator-activated recep-
tors (PPARa, PPARb/d and PPARc) are gene-specific transcription
factors whose activation by small lipophilic derived ligands leads
to significant improvement in insulin resistance, hyperglycaemia3,
endothelial function4, markers of inflammation5 and cholesterol
metabolism6. However, clinical use of PPAR ligands as thiazolidine-
diones or glitazars has been restricted by their side effect profile,
namely, fluid retention, congestive heart failure (CHF), adipogenic
weight gain, kidney impairment and a decrease in bone mineral
density associated with fractures7–11
. Recently, INT131 was
designed as a selective PPARc modulator (SPPARcM) to maintain
the benefits of the PPARc full agonists while reducing or deleting
their undesirable side effects12,13. This selective PPARc modulator
(SPPARcM) and others14 had partial agonist activity and showed
increased insulin sensitivity and robust glucose-lowering activity
with a reduction of the adverse effects observed with PPARc full
agonists, whatever the animal model of diabetes. These results
illustrated that anti-diabetic effects of PPAR ligands can be
decoupled from unwanted side effects as oedema or weight gain.
As a part of our programme, we were interested in developing
new SPPARcM ligands with full PPARc agonist activities as well as
moderating the adverse side effects as fluid retention or body-
2. Materials and methods
2.1. Chemistry
2.1.1. General
All reagents and solvents were purchased and used without fur-
€
ther purification. Melting points were determined on a BUCHI B-
weight gain. We have previously described a large series of 540 apparatus and are uncorrected. NMR spectra were recorded
a–ethoxyphenylpropionic acids bearing a benzoyl-indole core and on a Bruker Avance 300 spectrometer operating at 300 MHz (1H)
CONTACT Nicolas Lebegue
nicolas.lebegue@univ-lille.fr
Univ. Lille, Inserm, CHU Lille, UMR-S 1172 - JPArc - Centre de Recherche Jean-Pierre AUBERT
Neurosciences et Cancer, Lille, F-59000, France
ß 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited.

JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY
525
Figure 1. Design of a–alkoxyphenylpropionic acid derivatives bearing various central nitrogen heterocycles.
or 75 MHz (13C). Chemical shifts are in parts per million (ppm) and aqueous ammonium chloride solution (100 mL) and extracted
were referenced to the residual proton peaks in deuterated sol- twice with EtOAc (50 mL). The organic layers were dried over
vents. Mass spectra were recorded with an LCMS (Waters Alliance MgSO4, filtered and evaporated under reduced pressure. The resi-
Micromass ZQ 2000). LCMS analysis was performed using a Waters due was purified via flash column chromatography (cyclohexane/
XBridge C18 column (5 mm particle size column, dimensions EtOAc 6:4), yielding 10 as
a yellow solid (1.35 g, 82%);
C15H11F2NO2; MW¼ 275.26 g/mol; m.p. 161–163 ꢁC. 1H NMR
(300 MHz, CDCl3): d 5.82 (s, 1H); 6.85 (d, 1H, J ¼ 8.2 Hz); 7.30–7.37
(m, 5H); 7.44 (dd, 1H, J ¼ 1.6 Hz, 8.2 Hz); 7.57 (d, 1H, J ¼ 1.6 Hz);
8.63 (s, 1H); MS (ESIþ) m/z 276.1 [M þ H]þ.
50 mm ꢀ 4.6 mm). A gradient starting from 98% H2O/formate buf-
fer 5 mM (pH 3.8) and reaching 100% CH3CN/formate buffer 5 mM
(pH 3.8) within 4 min at a flow rate of 2 mL/min was used fol-
lowed by a return to the starting conditions within 1 min.
Elemental analyses were performed by UMR CNRS8181, and were
in agreement with the calculated values within 0.2%. Synthesis
of compounds 1–7 was performed according procedures well
described in the literature. Chiral HPLC method: Waters HPLC sys-
tem was equipped with a HPLC 600 pump and a 2996 photodiode
array detector. The HPLC column used was a Daicel Chiralpak AD
Column (250 ꢀ 4.6 mm). The eluents were: (A) IPA þ 0.1% TFA; (B)
n-hexane. The isocratic condition of elution was at a flow rate of 1
or 1.5 mL/min and at 20 ꢁC with a total run time of 40 min.
2.1.4. 5-Benzoyl-3,3-difluoro-1,3-dihydroindol-2-one (11)
Dess-Martin periodinane (1.1 g, 2.6 mmol, 1.3 eq) dissolved in DCM
(20 mL) was added to a solution of 10 (0.55 g, 2.0 mmol, 1.0 eq)
and the reaction mixture was stirred at room temperature for
2.5 h. The reaction mixture was quenched with a saturated aque-
ous ammonium chloride and sodium thiosulphate solution
(100 mL) and stirred until a clear solution was obtained. The solu-
tion was extracted twice with DCM, the organic layers were
washed with a saturated aqueous sodium chloride solution, dried
over MgSO4, filtered and evaporated under reduced pressure
yielding 11 as a yellow solid (0.504 g, 92%) which can be used
without further purification. C15H9F2NO2; MW¼ 273.24 g/mol; m.p.
154–156 ꢁC. 1H NMR (300 MHz, CDCl3): d 7.05 (d, 1H, J ¼ 8.2 Hz);
7.52 (m, 2H); 7.63 (m, 1H); 7.75 (m, 2H); 7.98–8.04 (m, 2H); 8.40 (s,
1H); MS (ESIþ) m/z 274.5 [M þ H]þ.
2.1.2. 5-Bromo-3,3-difluoro-1,3-dihydroindol-2-one (9)
DAST (5.33 mL, 40.7 mmol, 2.3 eq) was added to a solution of 5-
bromoisatine (8) (4 g, 17.7 mmol, 1.0 eq) in anhydrous DCM
(40 mL) and stirred at room temperature for 24 h under inert
atmosphere. The reaction mixture was quenched with CH3OH
(1 mL) then with water (50 mL) and extracted twice with DCM
(20 mL). The organic layers were dried over MgSO4, filtered and
evaporated under reduced pressure. The residue was purified via
flash column chromatography (cyclohexane/EtOAc 8:2), yielding
(9) as a yellow solid (3.82g, 88%); C8H4BrF2NO; MW ¼ 248.03g/mol;
2.1.5. Ethyl 2-diazo-2-(diethoxyphosphoryl)acetate (12)
The formation of benzenesulfonyl azide was accomplished accord-
ing to the published procedure16. In brief, benzenesulfonyl chlor-
ide (10 g, 56.6 mmol, 1.0 eq) in acetone (100 mL) and sodium
azide (5.52 g, 84.9 mmol, 1.5 eq) in water (20 mL) were combined
yielding 9.6 g of the desired reagent as a colourless liquid (93%);
1H NMR (CDCl3): d 7.63 (dd, 2H, J ¼ 7.2 and 8.3 Hz), 7.75 (dd, 1H,
J ¼ 7.2 Hz, J ¼ 1.5 Hz), 7.97 (dd, 2H, J ¼ 8.3 Hz, J ¼ 1.5 Hz). MS m/z
184 [M þ H]þ. Next stage was accomplished according to the pro-
cedure of Moody et al. [48]. Triethylphosphonoacetate (10.4 mL,
52.4 mmol, 1.0 eq) in dry THF (50 mL) was added dropwise to an
ice-cold suspension of 60% sodium hydride (3.14 g, 78.6 mmol, 1.5
m.p. 195–196 ꢁC. 1H NMR (300 MHz, CDCl3):
d 6.90 (d, 1H,
J ¼ 8.0 Hz); 7.57 (dd, 1H, J ¼ 2.0 Hz, 8.0 Hz); 7.67 (d, 1H, J ¼ 2.0 Hz);
8.12 (s, 1H); MS (ESIþ) m/z 247.6 [M þ H79Br]þ; 249.8 [M þ H81Br]þ.
2.1.3.
3,3-Difluoro-5-(hydroxyphenylmethyl)-1,3-dihydroindol-2-
one (10)
n-Butyllithium (15 mL, 1.6 M in hexane, 24 mmol, 4.0 eq) was
added at 0 ꢁC to a solution of i-PrMgCl (6 mL, 2 M in THF, 12 mmol,
2.0 eq) and the reaction mixture was stirred for 30 min. A solution
of 9 (1.5 g, 6 mmol, 1.0 eq) in anhydrous THF (20 mL) was then eq) in dry THF (50 mL). The reaction mixture was stirred at 0 ꢁC for
added at ꢂ10 ꢁC and the reaction mixture was stirred also for 1 h after which time benzenesulfonyl azide (9.6 g, 52.4 mmol, 1.0
30 min. A solution of benzaldehyde (3.7 mL, 36 mmol, 6.0 eq) in eq) in dry THF (100 mL) was added, under a constant flow of N2.
anhydrous THF (20 mL) was added dropwise at ꢂ78 ꢁC and the The reaction mixture was further stirred for 16 h at 0 ꢁC then
reaction mixture was stirred for 2 h then rised to room tempera- quenched by the addition of 5% aqueous solution of sodium
ture. The reaction mixture was quenched with
a saturated bicarbonate (200 mL). Thereafter, the aqueous phase was extracted

526
A. HURTEVENT ET AL.
with EtOAc which was washed with water and brine. The organic separated by filtration and the solvent evaporated under reduced
extract was then dried over MgSO4, filtered off and concentrated pressure. The crude product was purified via flash column chro-
in vacuo. The residue was purified via flash column chromatog- matography (cyclohexane/EtOAc 7:3).
raphy (cyclohexane/EtOAc 5:5), yielding 12 as a pale yellow liquid
1
(11.4 g, 87%); H NMR (CDCl3): d 1.19 (t, 3H, J ¼ 7.2 Hz), 1.36 (t, 6H,
J ¼ 7.2 Hz), 4.18–4.23 (m, 6H). MS m/z 251.1 [M þ H]þ.
2.1.11.
ate (17a)
Ethyl
3-[4–(2-chloroethoxy)-phenyl]-2-ethoxy-propion-
Colourless liquid; 93% yield; C15H21ClO4; MW¼ 300.8 g/mol; 1H
NMR (300 MHz, CDCl3): d 1.17 (t, 3H, J ¼ 7.1 Hz), 1.24 (t, 3H,
J ¼ 7.1 Hz), 2.97 (d, 2H, J ¼ 5.6 Hz), 3.33 (m, 1H), 3.59 (m, 1H), 3.81
(t, 2H, J ¼ 5.9 Hz), 3.98 (t, 1H, J ¼ 5.6 Hz), 4.12–4.25 (m, 4H), 6.85 (d,
2H, J ¼ 8.6 Hz), 7.17 (d, 2H, J ¼ 8.6 Hz); MS (ESIþ) m/z 300.1
[M þ H35Cl]þ, 302.2 [M þ H37Cl]þ.
2.1.6. General procedure for synthesis of alkoxy phosphonoace-
tates (13a,b)
This conversion was performed according to the method of Haigh
et al.17. A mixture of diazo ester 12 (10 g, 40 mmol), ethanol
(23.6 mL, 400 mmol) or 2-trifluoroethanol (28.7 mL, 400 mmol) and
Rh(II) acetate dimer (176.8 mg, 0.4 mmol) in toluene (60 mL) was
heated with stirring at reflux for 4 h. The solution was concen-
trated in vacuo, hydrolysed and extracted 3 times with EtOAc. The
combined organic extracts were washed with water, brine, dried
over MgSO4, filtered off and concentrated under reduced pressure.
The resulting colourless liquid was used in the next step without
further purification.
2.1.12. Ethyl 3-[4–(2-chloroethoxy)-phenyl]-2,2,2-trifluoroethoxy-
propionate (17 b)
Colourless liquid; 97% yield; C15H18ClF3O4; MW¼ 354.8 g/mol; 1H
NMR (300 MHz, CDCl3): d 1.25 (t, 3H, J ¼ 7.1 Hz), 3.02 (m, 2H), 3.69
(m, 1H), 3.80 (t, 2H, J ¼ 5.9 Hz), 3.99 (m, 1H), 4.18 (m, 5H), 6.84 (d,
2H, J ¼ 8.8 Hz), 7.16 (d, 2H, J ¼ 8.8 Hz); MS (ESIþ) m/z 354.2
[M þ H35Cl]þ, 356.2 [M þ H37Cl]þ.
2.1.7. Ethyl 2-ethoxy-2-(diethylphosphono)acetate (13a)
Colourless liquid; 80% yield; C10H21O6P; MW¼ 268.2 g/mol; 1H
NMR (300 MHz, CDCl3): d 1.24–1.35 (m, 12H), 3.55 (m, 1H), 3.70 (m,
1H), 4.23–4.28 (m, 6H), 4.35 (s, 1H). MS (ESIþ) m/z 269.2 [M þ H]þ.
2.1.13. General procedure for synthesis of propionic acid (18a,b)
Lithium hydroxide (0.49 g, 20.4 mmol, 3.0 eq) was added to a solu-
tion of 17a (2 g, 6.6 mmol, 1.0 eq) or 17 b (2.36 g, 6.6 mmol, 1.0
eq) dissolved in a 1: 1 mixture of THF (30 mL) and water (30 mL),
and the mixture was then stirred at room temperature for 20 h.
Thereafter the whole was concentrated in vacuo, and the concen-
trate subjected to vigorous stirring at 0 ꢁC as the solution pH was
adjusted to 1 with additions of aliquots of 1 M HCl. The resulting
precipitate was filtered, washed with water, pentane and dried
under reduced pressure.
2.1.8. Ethyl 2,2,2-trifluoroethoxy-2-(diethylphosphono)acetate (13 b)
Colourless liquid; 80% yield; C10H18F3O6P; MW¼ 322.1 g/mol; 1H
NMR (300 MHz, CDCl3): d 1.24–1.35 (m, 9H), 3.90 (m, 1H), 4.11 (m,
1H), 4.21–4.28 (m, 6H), 4.51 (s, 1H). MS (ESIþ) m/z 323.2 [M þ H]þ.
2.1.9. 4–(2-Chloroethoxy)benzaldehyde (15)
A mixture of 4-hydroxybenzaldehyde (14) (10 g, 80 mmol), potas-
sium carbonate (22 g, 160 mmol) and 1-bromo-2-chloroethane
(30 mL, 320 mmol) was refluxed in CH3CN (80 mL) for 15 h. The
reaction mixture was filtered and the filtrate evaporated under
reduced pressure. The residue was purified via flash column chro-
matography (cyclohexane/EtOAc 7:3), yielding 15 as a white pow-
der (13.6 g, 92%); C9H9ClO2; MW¼ 184.6 g/mol; mp 29–32 ꢁC. 1H
NMR (300 MHz, CDCl3): d 3.86 (t, 2H, J ¼ 6.1 Hz), 4.32 (t, 2H,
J ¼ 6.1 Hz), 7.03 (d, 2H, J ¼ 8.9 Hz), 7.86 (d, 2H, J ¼ 8.9 Hz), 9.90 (s,
1H). MS (ESIþ) m/z 185 [M þ H35Cl]þ, 187 [M þ H37Cl]þ.
2.1.14. 3-[4–(2-Chloroethoxy)-phenyl]-2-ethoxy-propionic acid (18a)
White solid; 85%; C13H17ClO4; MW ¼ 272.72 g/mol; mp 49–51 ꢁC;
1H NMR (DMSO-d6): d 1.04 (t, 3H, J ¼ 7.0 Hz), 2.83 (m, 2H), 3.29 (m,
1H), 3.52 (m, 1H), 3.92 (t, 2H, J ¼ 5.5 Hz), 4.03 (m, 1H), 4.21 (t, 2H,
J ¼ 5.5 Hz), 6.87 (d, 2H, J ¼ 8.5 Hz), 7.14 (d, 2H, J ¼ 8.5 Hz); MS
(ESIþ) m/z 273.2 [M þ H35Cl]þ, 275.3 [M þ H37Cl]þ.
2.1.15. 3-[4–(2-Chloroethoxy)-phenyl]-2,2,2-trifluoroethoxy-propionic
acid (18 b)
White solid; 91%; C13H14ClF3O4; MW¼ 326.72 g/mol; mp 70–72 ꢁC;
1H NMR (CDCl3): d 3.03 (dd, 1H, J ¼ 8.05 Hz, 14.4 Hz), 3.16 (dd, 1H,
J ¼ 4 Hz, 14.4 Hz); 3.71 (m, 1H), 3.81 (t, 2H, J ¼ 5.85 Hz), 4.01 (m,
1H), 4.22 (m, 3H), 6.87 (d, 2H, J ¼ 8.7 Hz), 7.19 (d, 2H, J ¼ 8.7 Hz),
9.85 (s, 1H); MS (ESIþ) m/z 327.3 [M þ H35Cl]þ, 329.4 [M þ H37Cl]þ.
2.1.10. General procedure for synthesis of propionate (17a,b)
Phosphonoacetate 13a (5 g, 18.6 mmol) or 13 b (6 g, 18.6 mmol) in
THF (50 mL) was added dropwise to a suspension of 60% sodium
hydride (0.93 g, 23.2 mmol, 1.5 eq) in anhydrous THF (100 mL) at
0 ꢁC under a constant flow of N2 and the reaction mixture was
stirred at 0 ꢁC for 1 h. Benzaldehyde 15 (2.85 g, 15.5 mmol) was
then added in dry THF (50 mL). Post stirring for a further 4 h at
2.1.16. General procedure for synthesis of diastereoisomers (19a,b
room temperature, the solution was concentrated in vacuo and and 20a,b)
the residue dissolved in EtOAc for washing with water and brine.
Combined organic extracts were dried over MgSO4, filtered off
and concentrated in vacuo leading a residue that was purified by
To a solution of 18a (3.4 g, 12.5 mmol, 1.0 eq) or 18 b (4.09 g,
12.5 mmol, 1.0 eq) in DCM (150 mL) at 0 ꢁC; EDCI (2.87 g,
15.0 mmol, 1.2 eq), (S)-(-)-2-phenylgycinol (1.74 g, 12.5 mmol, 1.0
flash column (cyclohexane/EtOAc 8:2) to yield 16a,b (66–92% eq), and HOBT (2.0 g, 15.0 mmol, 1.2 eq) were added. Finally, trie-
yield) as mixtures of two isomers (ratio Z: E ¼ 60: 40) which were thylamine (2.1 mL, 15.0 mmol, 1.2 eq) was added dropwise at 0 ꢁC.
not separated and directly used in the next catalytic hydrogen- The reaction mixture was then stirred for 12 h at ambient tem-
ation step. A solution of 16a,b (13.2 mmol) in ethanol (150 mL) perature, quenched with saturated aqueous ammonium chloride
was stirred with 10% Pd/C catalyst at room temperature under solution, and diluted with DCM. The organic layer was washed
an atmospheric pressure of hydrogen for 20 h. The catalyst is with water, dried over MgSO4, filtered, concentrated in vacuo and

JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY
527
the resulting residue was purified via flash column chromatog- 1H), 3.52 (m, 1H), 3.92 (t, 2H, J ¼ 5.5 Hz), 4.03 (m, 1H), 4.21 (t, 2H,
raphy (petroleum ether/EtOAc 45:55).
J ¼ 5.5 Hz), 6.87 (d, 2H, J ¼ 8.5 Hz), 7.14 (d, 2H, J ¼ 8.5 Hz); MS
(ESIþ) m/z 273.2 [M þ H35Cl]þ, 275.3 [M þ H37Cl]þ. Chiral HPLC
method: flow rate¼ 1.0 mL/min, eluents ¼ A/B 5:95, tr¼ 16.62 min.
2.1.17. 2-(S)-3-[4–(2-Chloroethoxy)-phenyl]-2-ethoxy-N-((S)-2-hydroxy-
1-phenylethyl) propanamide (19a)
Off-white solid; 37%; C21H26ClNO4; MW¼ 391.88 g/mol; mp
2.1.23. 2-(S)- 3-[4–(2-Chloroethoxy)-phenyl]- 2,2,2-trifluoroethoxy-
1
135–137 ꢁC; H NMR (CDCl3): d 1.21 (t, 3H, J ¼ 7.0 Hz), 2.51 (m, 1H);
propionic acid (21b)
White solid; 84%; C13H14ClF3O4; MW¼ 326.72 g/mol; mp 70–72 ꢁC;
1H NMR (CDCl3): d 3.03 (dd, 1H, J ¼ 8.05 Hz, 14.4 Hz), 3.16 (dd, 1H,
J ¼ 4 Hz, 14.4 Hz); 3.71 (m, 1H), 3.81 (t, 2H, J ¼ 5.85 Hz), 4.01 (m,
1H), 4.22 (m, 3H), 6.87 (d, 2H, J ¼ 8.7 Hz), 7.19 (d, 2H, J ¼ 8.7 Hz),
9.85 (s, 1H); MS (ESIþ) m/z 327.3 [M þ H35Cl]þ, 329.4 [M þ H37Cl]þ.
Chiral HPLC method: flow rate¼ 1.0 mL/min, eluents ¼ A/B 5:95,
tr¼ 14.85 min.
2.91 (dd, 1H, J ¼ 6.75 Hz, 14.3 Hz), 3.09 (dd, 1H, J ¼ 3.75 Hz,
14.3 Hz), 3.58 (m, 2H), 3.85 (m, 4H), 4.02 (dd, 1H, J ¼ 3.75 Hz,
6.75 Hz), 4.19 (t, 2H, J ¼ 5.8 Hz), 5.01 (m, 1H), 6.78 (d, 2H,
J ¼ 8.7 Hz), 7.07 (dd, 2H, J ¼ 2.0 Hz, 7.6 Hz), 7.13 (m, 3H), 7.33 (m,
3H); MS (ESIþ) m/z 392.3 [M þ H35Cl]þ, 394.3 [M þ H37Cl]þ.
2.1.18. 2-(S)-3-[4–(2-Chloroethoxy)-phenyl]-2,2,2-trifluoroethoxy-N-
((S)-2-hydroxy-1-phenylethyl) propanamide (19 b)
Off-white solid; 37%; C21H23ClF3NO4; MW¼ 445.86 g/mol; mp
139–140 ꢁC; 1H NMR (CDCl3): d 2.21 (t, 1H, J ¼ 6.85 Hz), 2.94 (dd,
1H, J ¼ 7.25 Hz, 14.55 Hz), 3.16 (dd, 1H, J ¼ 3.45 Hz, 14.55 Hz),
3.75–3.88 (m, 6H), 4.14–4.22 (m, 3H), 5.03 (m, 1H), 6.79 (d, 2H,
J ¼ 8.55 Hz), 7.00 (d, 1H, J ¼ 7.25 Hz), 7.07–7.13 (m, 4H), 7.33 (m,
3H); MS (ESIþ) m/z 447.1 [M þ H35Cl]þ, 449.0 [M þ H37Cl]þ.
2.1.24. 2-(R)- 3-[4–(2-Chloroethoxy)-phenyl]-2-ethoxypropionic
acid (22a)
White solid; 78%; C13H17ClO4; MW ¼ 272.72 g/mol; mp 49–51 ꢁC;
1H NMR (DMSO-d6): d 1.04 (t, 3H, J ¼ 7.0 Hz), 2.83 (m, 2H), 3.29 (m,
1H), 3.52 (m, 1H), 3.92 (t, 2H, J ¼ 5.5 Hz), 4.03 (m, 1H), 4.21 (t, 2H,
J ¼ 5.5 Hz), 6.87 (d, 2H, J ¼ 8.5 Hz), 7.14 (d, 2H, J ¼ 8.5 Hz); MS
(ESIþ) m/z 273.2 [M þ H35Cl]þ, 275.3 [M þ H37Cl]þ. Chiral HPLC
method: flow rate¼ 1.0 mL/min, eluents ¼ A/B 5:95, tr¼ 12.48 min.
2.1.19. 2-(R)-3-[4–(2-Chloroethoxy)-phenyl]-2-ethoxy-N-((S)-2-hydroxy-
1-phenylethyl) propanamide (20a)
Off-white solid; 33%; C21H26ClNO4; MW ¼ 391.88 g/mol; mp
1
2.1.25. 2-(R)- 3-[4–(2-Chloroethoxy)-phenyl]- 2,2,2-trifluoroethoxy-
propionic acid (22 b)
127–128 ꢁC; H NMR (CDCl3): d 1.16 (t, 3H, J ¼ 7.0 Hz), 2.48 (dd, 1H,
J ¼ 5.25 Hz, 7.5 Hz); 2.96 (dd, 1H, J ¼ 6.4 Hz, 14.3 Hz), 3.15 (dd, 1H,
J ¼ 4.0 Hz, 14.3 Hz), 3.52 (m, 2H), 3.71 (m, 2H), 3.83 (t, 2H,
J ¼ 5.8 Hz), 4.0 (dd, 1H, J ¼ 4.0 Hz, 6.4 Hz), 4.24 (t, 2H, J ¼ 5.8 Hz),
4.99 (m, 1H), 6.88 (d, 2H, J ¼ 8.7 Hz), 7.03 (d, 2H, J ¼ 7.3 Hz), 7.20
(m, 3H), 7.34 (m, 3H); MS (ESIþ) m/z 392.3 [M þ H35Cl]þ,
394.3 [M þ H37Cl]þ.
White solid; 68%; C13H14ClF3O4; MW ¼ 326.72 g/mol; mp 70–72 ꢁC;
1H NMR (CDCl3): d 3.03 (dd, 1H, J ¼ 8.05 Hz, 14.4 Hz), 3.16 (dd, 1H,
J ¼ 4 Hz, 14.4 Hz); 3.71 (m, 1H), 3.81 (t, 2H, J ¼ 5.85 Hz), 4.01 (m,
1H), 4.22 (m, 3H), 6.87 (d, 2H, J ¼ 8.7 Hz), 7.19 (d, 2H, J ¼ 8.7 Hz),
9.85 (s, 1H); MS (ESIþ) m/z 327.3 [M þ H35Cl]þ, 329.4 [M þ H37Cl]þ.
Chiral HPLC method: flow rate¼ 1.0 mL/min, eluents ¼ A/B 5:95,
tr¼ 12.63 min.
2.1.20. 2-(R)-3-[4–(2-Chloroethoxy)-phenyl]-2,2,2-trifluoroethoxy-N-
((S)-2-hydroxy-1-phenylethyl) propanamide (20 b)
Off-white solid; 37%; C21H23ClF3NO4; MW¼ 445.86 g/mol; mp 2.1.26. General procedure for synthesis of N-alkylated benzoyl het-
126–127 ꢁC; 1H NMR (CDCl3): d 2.11 (t, 1H, J ¼ 6.35 Hz), 3.02 (dd,
erocycles (23–30)
1H, J ¼ 6.75 Hz, 14.2 Hz), 3.21 (dd, 1H, J ¼ 3.7 Hz, 14.2 Hz), 3.66–3.75
To a solution of benzoyl heterocycle derivative 1–7 or 11 (0.5 g,
(m, 3H), 3.78–3.85 (m, 3H), 4.13 (dd, 1H, J ¼ 3.7 Hz, 6.35 Hz), 4.23 (t,
2.17 mmol, 1.0 eq) in DMF (35 mL) was added potassium carbon-
ate (0.9 g, 6.5 mmol, 3 eq) and the mixture was stirred for 1 h at
100 ꢁC. A solution of 17a (0.77 g, 2.6 mmol, 1.2 eq) or 17 b (0.85 g,
2.6 mmol, 1.2 eq) in DMF (5 mL) was added dropwise and the mix-
ture was stirred at 120 ꢁC for 15 h. After cooling, the reaction mix-
2H, J ¼ 5.9 Hz), 5.01 (m, 1H), 6.89 (d, 2H, J ¼ 8.8 Hz), 6.93 (d, 1H,
J ¼ 7.35 Hz), 7.18–7.22 (m, 4H), 7.29–7.37 (m, 3H); MS (ESIþ) m/z
447.1 [M þ H35Cl]þ, 449.0 [M þ H37Cl]þ.
ture was filtered, hydrolysed and extracted twice with EtOAc. The
combined organic extracts were washed with water, dried over
MgSO4, filtered off and concentrated in vacuo. The crude product
was purified via flash column chromatography (cyclohexane/
EtOAc 7:3) to afford the corresponding N-alkylated heterocycle
derivatives.
2.1.21. General procedure for synthesis of optically pure propionic
acids (21a,b and 22a,b)
5M aqueous solution of H2SO4 (82 mL, 408 mmol, 100 eq) was
added to a solution of 19a or 20a (1.6 g, 4.08 mmol, 1 eq) or 19 b
or 20 b (1.8 g, 4.08 mmol, 1 eq) in a 1: 1 mixture of 1,4-dioxane
(80 mL) and water (80 mL). The reaction mixture was refluxed for
8 h, cooled to room temperature, diluted with EtOAc, and the
resulting organic layer was washed with H2O, dried over MgSO4,
2.1.27. Ethyl 3-f4-[2–(5-benzoyl-2-oxo-benzothiazol-3-yl)-ethoxy]-
filtered, concentrated in vacuo and the brown residue was purified
phenylg-2-ethoxypropionate (23)
by flash column chromatography (DCM/MeOH/NEt3 96:2:2).
Colourless gum; 58% yield; C29H29NO6S; MW¼ 519.62 g/mol; 1H
NMR (CDCl3): d 1.16 (t, 3H, J ¼ 7 Hz); 1.24 (t, 3H, J ¼ 7 Hz); 2.93 (d,
2H, J ¼ 6.1 Hz); 3.35 (m, 1H); 3.59 (m, 1H); 3.95 (t, 1H, J ¼ 6.1 Hz);
2.1.22. 2-(S)- 3-[4–(2-Chloroethoxy)-phenyl]-2-ethoxypropionic
4.16 (q, 2H, J ¼ 7 Hz); 4.29 (t, 2H, J ¼ 5 Hz); 4.42 (t, 2H, J ¼ 5 Hz);
acid (21a)
1
White solid; 81%; C13H17ClO4; MW¼ 272.72 g/mol; mp 49–51 ꢁC; H
6.74 (d, 2H, J ¼ 8.5 Hz); 7.12–7.16 (m, 4H); 7.25 (d, 1H, J ¼ 7.9 Hz);
NMR (DMSO-d6): d 1.04 (t, 3H, J ¼ 7.0 Hz), 2.83 (m, 2H), 3.29 (m, 7.52 (d, 2H, J ¼ 7.6 Hz); 7.60 (dd, 1H, J ¼ 1.5 Hz, 7.9 Hz); 7.83 (dd,

528
A. HURTEVENT ET AL.
1H, J ¼ 1.2 Hz, 8.2 Hz); 7.90 (d, 1H, J ¼ 1.5 Hz); MS (ESIþ) m/z 2.1.33. Ethyl 3-f4-[2–(7-benzoyl-3-oxo-benzo[1, 4]oxazin-4-yl)-
520.3 [M þ H]þ.
ethoxy]-phenylg-2-ethoxypropionate (28)
Colourless gum; 69% yield; C30H31NO7; MW ¼ 517.58 g/mol; 1H
NMR (CDCl3): d 1.16 (t, 3H, J ¼ 6.85 Hz); 1.24 (t, 3H, J ¼ 7.2 Hz); 2.94
(m, 2H); 3.34 (m, 1H); 3.60 (m, 1H); 3.95 (dd, 1H, J ¼ 6 Hz, 7.3 Hz);
4.17 (q, 2H, J ¼ 7.2 Hz); 4.28 (t, 2H, J ¼ 5.05 Hz); 4.37 (t, 2H,
J ¼ 5.05 Hz); 4.68 (s, 2H); 6.79 (d, 2H, J ¼ 8.7 Hz); 7.15 (d, 2H,
J ¼ 8.7 Hz); 7.45 (d, 1H, J ¼ 8.4 Hz); 7.47–7.53 (m, 3H); 7.57 (dd, 1H,
J ¼ 1.9 Hz, 8.4 Hz); 7.61 (t, 1H, J ¼ 7.2 Hz); 7.79 (dd, 2H, J ¼ 1.45 Hz,
8.4 Hz). MS (ESIþ) m/z 518.4 [M þ H]þ.
2.1.28. Ethyl 3-f4-[2–(6-benzoyl-2-oxo-benzothiazol-3-yl)-ethoxy]-
phenylg-2-ethoxypropionate (24a)
Colourless gum; 61% yield; C29H29NO6S; MW¼ 519.62 g/mol; 1H
NMR (CDCl3): d 1.15 (t, 3H, J ¼ 7.05 Hz); 1.24 (t, 3H, J ¼ 7.05 Hz);
2.93 (d, 2H, J ¼ 6.15 Hz); 3.33 (m, 1H); 3.59 (m, 1H); 3.94 (t, 1H,
J ¼ 6.5 Hz); 4.16 (q, 2H, J ¼ 7.05 Hz); 4.30 (t, 2H, J ¼ 5.05 Hz); 4.40 (t,
2H, J ¼ 5.05 Hz); 6.74 (d, 2H, J ¼ 9 Hz); 7.14 (d, 2H, J ¼ 9 Hz); 7.42 (d,
1H, J ¼ 8.45 Hz); 7.51 (t, 2H, J ¼ 8 Hz); 7.62 (t, 1H, J ¼ 7.5 Hz); 7.79
(d, 2H, J ¼ 8 Hz); 7.87 (dd, 1H, J ¼ 1.65 Hz, 8.45 Hz); 7.93 (d, 1H,
J ¼ 1.65 Hz). MS (ESIþ) m/z 520.3 [M þ H]þ.
2.1.34.
Ethyl
3-f4-[2–(5-benzoyl-2-oxo-2,3-dihydroindol-1-
yl)ethoxy]phenylg-2-ethoxypropionate (29)
Colourless gum; 68% yield; C30H31NO6; MW¼ 501.57 g/mol; 1H
NMR (CDCl3): d 1.15 (t, 3H, J ¼ 7 Hz); 1.25 (t, 3H, J ¼ 7.3 Hz); 2.64 (s,
2H); 2.93 (m, 2H); 3.44 (m, 1H); 3.59 (m, 1H); 3.94 (m, 1H);
4.12–4.23 (m, 4H); 4.28 (t, 2H, J ¼ 7 Hz); 6.73 (d, 2H, J ¼ 8.8 Hz); 7.14
(d, 2H, J ¼ 8.8 Hz); 7.30 (d, 1H, J ¼ 8.5 Hz); 7.52 (m, 2H); 7.60 (m,
1H); 7.78 (m, 2H); 8.01 (d, 1H, J ¼ 1.4 Hz); 8.28 (dd, 1H, J ¼ 1.4 Hz,
8.5 Hz). MS (ESIþ) m/z 502.4 [M þ H]þ.
2.1.29. Ethyl 3-f4-[2–(6-benzoyl-2-oxo-benzothiazol-3-yl)-ethoxy]-
phenylg-2–(2,2,2-trifluoroethoxy)propionate (24 b)
Colourless gum; 64% yield; C29H26F3NO6S; MW¼ 573.58 g/mol; 1H
NMR (CDCl3): d 1.25 (t, 3H, J ¼ 7.1 Hz); 3.01 (m, 2H); 3.67 (m, 1H);
4.00 (m, 1H), 4.11–4.22 (m, 3H), 4.30 (t, 2H, J ¼ 4.55 Hz); 4.40 (t, 2H,
J ¼ 4.55 Hz); 6.75 (d, 2H, J ¼ 8.8 Hz); 7.13 (d, 2H, J ¼ 8.8 Hz); 7.41 (d,
1H, J ¼ 8.55 Hz); 7.51 (t, 2H, J ¼ 7.6 Hz); 7.62 (t, 1H, J ¼ 7.6 Hz); 7.79
(d, 2H, J ¼ 8.2 Hz); 7.87 (dd, 1H, J ¼ 1.75 Hz, 8.55 Hz); 7.93 (d, 1H,
J ¼ 1.75 Hz). MS (ESIþ) m/z 574.3 [M þ H]þ.
2.1.35. Ethyl 3-f4-[2–(5-benzoyl-3,3-difluoro-2-oxo-2,3-dihydroin-
dol-1-yl)ethoxy]phenylg-2-ethoxypropionate (30)
Colourless gum; 62% yield; C30H29F2NO6; MW¼ 537.57 g/mol; 1H
NMR (CDCl3): d 1.15 (t, 3H, J ¼ 7 Hz); 1.25 (t, 3H, J ¼ 7.3 Hz); 2.93
(m, 2H); 3.32 (m, 1H); 3.59 (m, 1H); 3.94 (m, 1H); 4.12–4.23 (m, 4H);
4.28 (t, 2H, J ¼ 7 Hz); 6.73 (d, 2H, J ¼ 8.8 Hz); 7.14 (d, 2H, J ¼ 8.8 Hz);
7.30 (d, 1H, J ¼ 8.5 Hz); 7.52 (m, 2H); 7.60 (m, 1H); 7.78 (m, 2H);
8.01 (d, 1H, J ¼ 1.4 Hz); 8.08 (dd, 1H, J ¼ 1.4 Hz, 8.5 Hz). MS (ESIþ)
m/z 538.3 [M þ H]þ.
2.1.30. Ethyl 3-f4-[2–(6-benzoyl-3-oxo-benzo[1, 4]thiazin-4-yl)-
ethoxy]-phenylg-2-ethoxypropionate (25)
Colourless gum; 48% yield; C30H31NO6S; MW¼ 533.65 g/mol; 1H
NMR (CDCl3): d 1.16 (t, 3H, J ¼ 7 Hz); 1.25 (t, 3H, J ¼ 7.2 Hz); 2.93 (d,
2H, J ¼ 6.2 Hz); 3.33 (m, 1H); 3.48 (s, 2H); 3.61 (m, 1H); 3.95 (t, 1H,
J ¼ 6.2 Hz); 4.18 (q, 2H, J ¼ 7.2 Hz); 4.29 (t, 2H, J ¼ 4.8 Hz); 4.36 (t,
2H, J ¼ 4.8 Hz); 6.68 (d, 2H, J ¼ 8.3 Hz); 7.11 (d, 2H, J ¼ 8.3 Hz); 7.19
(m, 2H); 7.51 (dd, 2H, J ¼ 7.5 Hz, 8.3 Hz); 7.62 (dd, 1H, J ¼ 1.5 Hz,
7.5 Hz); 7.84 (dd, 2H, J ¼ 1.5 Hz, 8.3 Hz); 8.25 (d, 1H, J ¼ 1.8 Hz). MS
(ESIþ) m/z 534.3 [M þ H]þ.
2.1.36. General procedure for synthesis of carboxylic acids (31–38)
A solution of ester 23–30 (0.5 mmol, 1.0 eq) and lithium hydroxide
(36 mg, 1.5 mmol, 3.0 eq) in THF/H2O (3:2, 15 mL) is stirred at
room temperature for 10 h. After removal of the solvent in vacuo,
1 N HCl aqueous solution (10 mL) is added and the resulting pre-
cipitate is filtered and purified by flash column chromatography
(DCM/MeOH 9:1) to yield the corresponding carboxylic acid.
2.1.31. Ethyl 3-f4-[2–(7-benzoyl-3-oxo-benzo[1, 4]thiazin-4-yl)-
ethoxy]-phenylg-2-ethoxypropionate (26)
Colourless gum; 78% yield; C30H31NO6S; MW¼ 533.65 g/mol; 1H
NMR (CDCl3): d 1.16 (t, 3H, J ¼ 7.1 Hz); 1.24 (t, 3H, J ¼ 7.1 Hz); 2.95
(d, 2H, J ¼ 5.7 Hz); 3.34 (m, 1H); 3.46 (s, 2H); 3.61 (m, 1H); 3.96 (t,
1H, J ¼ 5.7 Hz); 4.17 (q, 2H, J ¼ 7.1 Hz); 4.32 (t, 2H, J ¼ 4.6 Hz); 4.39
(t, 2H, J ¼ 4.6 Hz); 6.81 (d, 2H, J ¼ 8.6 Hz); 7.16 (d, 2H, J ¼ 8.6 Hz);
7.50 (m, 2H); 7.63 (dd, 1H, J ¼ 1.4 Hz, 7.1 Hz); 7.69 (d, 1H,
J ¼ 8.7 Hz); 7.76 (dd, 1H, J ¼ 1.7 Hz, 8.7 Hz); 7.80 (dd, 2H, J ¼ 1.3 Hz,
7 Hz); 7.86 (d, 1H, J ¼ 1.7 Hz). MS (ESIþ) m/z 534.3 [M þ H]þ.
2.1.37. 3-f4-[2–(5-benzoyl-2-oxo-benzothiazol-3-yl)-ethoxy]-phenylg-
2-ethoxypropionic acid (31)
Pale yellow solid; 82% yield; C27H25NO6S; MW ¼ 491.57 g/mol;
1
m.p. 49–51 ꢁC. H NMR (CDCl3): d 1.18 (t, 3H, J ¼ 7 Hz); 3.06 (d, 2H,
J ¼ 6.4 Hz); 3.53 (m, 2H); 4.11 (t, 1H, J ¼ 6.4 Hz); 4.31 (t, 2H,
J ¼ 5 Hz); 4.42 (t, 2H, J ¼ 5 Hz); 6.76 (d, 2H, J ¼ 8.8 Hz); 7.10–7.13 (m,
4H); 7.23–7.26 (m, 4H); 7.83 (dd, 1H, J ¼ 1.5 Hz, 7 Hz); 7.88 (d, 1H,
J ¼ 1.5 Hz); 13 C NMR (75 MHz, CDCl3): d 15.0, 37.6, 42.8, 65.5, 66.9,
79.6, 112.6, 114.3, 121.9, 125.4, 128.4, 129.9, 130.0, 130.6, 132.6,
134.6, 135.8, 137.4, 137.9, 156.9, 169.8, 173.7, 195.7. tR,LCMS
¼
2.1.32. Ethyl 3-f4-[2–(6-benzoyl-3-oxo-benzo[1, 4]oxazin-4-yl)-
ethoxy]-phenylg-2-ethoxypropionate (27)
2.44 min; MS (ESIþ) m/z 492.3 [M þ H]þ. Anal. Calcd (%) for
C27H25NO6S: C, 65.97; H, 5.13; N, 2.85; found C, 65.63; H, 5.31;
N, 2.64.
Colourless gum; 73% yield; C30H31NO7; MW¼ 517.58 g/mol; 1H
NMR (CDCl3): d 1.16 (t, 3H, J ¼ 7.1 Hz); 1.24 (t, 3H, J ¼ 7.2 Hz); 2.95
(d, 2H, J ¼ 5.3 Hz); 3.34 (m, 1H); 3.60 (m, 1H); 3.95 (t, 1H,
J ¼ 5.3 Hz); 4.15 (q, 2H, J ¼ 5.2 Hz); 4.26 (t, 2H, J ¼ 5.2 Hz); 4.37 (t, 2.1.38. 3-f4-[2–(6-benzoyl-2-oxo-benzothiazol-3-yl)-ethoxy]-phenylg-
2H, J ¼ 5.2 Hz); 4.72 (s, 2H); 6.75 (d, 2H, J ¼ 9.1 Hz); 7.06 (d, 1H,
2-ethoxypropionic acid (32a)
J ¼ 8.1 Hz); 7.13 (d, 2H, J ¼ 9.1 Hz); 7.27 (dd, 1H, J ¼ 1.9 Hz, 8.1 Hz);
7.48 (m, 2H); 7.60 (m, 1H); 7.81 (m, 2H); 8.03 (d, 1H, J ¼ 1.9 Hz). MS
(ESIþ) m/z 518.4 [M þ H]þ.
Off-white solid; 79% yield; C27H25NO6S; MW¼ 491.57 g/mol; m.p.
57–59 ꢁC. 1H NMR (CDCl3): d 1.16 (t, 3H, J ¼ 6.95 Hz); 2.93 (dd, 1H,
J ¼ 7.55 Hz, 14.05 Hz); 3.04 (dd, 1H, J ¼ 4.4 Hz, 14.05 Hz); 3.41 (m,

JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY
529
1H); 3.60 (m, 1H); 4.02 (dd, 1H, J ¼ 4.4 Hz, 7.65 Hz); 4.30 (t, 2H, 2.1.42. 3-f4-[2–(6-benzoyl-3-oxo-benzo[1, 4]oxazin-4-yl)-ethoxy]-
J ¼ 5.45 Hz); 4.40 (t, 2H, J ¼ 5.45 Hz); 6.74 (d, 2H, J ¼ 8.5 Hz); 7.13 (d,
2H, J ¼ 8.5 Hz); 7.41 (d, 1H, J ¼ 8.6 Hz); 7.51 (t, 2H, J ¼ 7.8 Hz); 7.62
(t, 1H, J ¼ 7.5 Hz); 7.78 (d, 2H, J ¼ 8 Hz); 7.86 (dd, 1H, J ¼ 1.8 Hz,
phenylg-2-ethoxypropionic acid (35)
Off-white solid; 76% yield; C28H27NO7; MW ¼ 489.53 g/mol; m.p.
47–49 ꢁC. 1H NMR (CDCl3): d 1.17 (t, 3H, J ¼ 7.5 Hz); 2.94 (m, 1H);
8.5 Hz); 7.92 (d, 1H, J ¼ 1.8 Hz). 13 C NMR (75 MHz, CDCl3): d 15.0, 3.04 (m, 1H); 3.45 (m, 1H); 3.58 (m, 1H); 4.02 (dd, 1H, J ¼ 4.25 Hz,
7.4 Hz); 4.26 (t, 2H, J ¼ 5 Hz); 4.36 (t, 2H, J ¼ 5 Hz); 4.70 (s, 2H); 6.75
37.7, 42.9, 65.5, 66.7, 79.6, 111.1, 114.2, 122.6, 124.8, 128.4, 129.0,
(d, 2H, J ¼ 8.65 Hz); 7.04 (d, 1H, J ¼ 8.2 Hz); 7.12 (d, 2H, J ¼ 8.65 Hz);
129.5, 129.8, 130.6, 132.4, 132.6, 137.6, 140.9, 156.8, 170.4, 175.1,
195.1153. tR,LCMS ¼ 2.45 min; MS (ESIþ) m/z 492.3 [M þ H]þ. Anal.
Calcd (%) for C27H25NO6S: C, 65.97; H, 5.13; N, 2.85; found C,
65.77; H, 5.31; N, 2.68.
7.45–7.52 (m, 3H); 7.59 (m, 1H); 7.79 (d, 2H, J ¼ 8.55 Hz); 8.00 (d,
1H, J ¼ 1.75 Hz); 13 C NMR (75 MHz, CDCl3): d 15.0, 29.7, 37.7, 42.0,
65.2, 67.6, 79.7, 114.2, 114.3, 116.4, 118.0, 127.4, 128.3, 129.8,
129.8, 130.5, 130.6, 132.4, 137.6, 148.9, 157.1, 164.0, 173.9, 195.1.
tR,LCMS ¼ 2.30 min; MS (ESIþ) m/z 490.3 [M þ H]þ. Anal. Calcd (%)
for C28H27NO7: C, 68.70; H, 5.56; N, 2.86; found C, 68.53; H, 5.31;
N, 2.63.
2.1.39.
3-f4-[2–(6-benzoyl-2-oxo-benzothiazol-3-yl)-ethoxy]-phe-
nylg-2–(2,2,2-trifluoro)ethoxy-propionic acid (32 b)
Off-white solid; 74% yield; C27H22F3NO6S; MW ¼ 545.52 g/mol;
m.p. 60–62 ꢁC. 1H NMR (CDCl3):
d
2.99 (dd, 1H, J ¼ 7.8 Hz,
2.1.43. 3-f4-[2–(7-benzoyl-3-oxo-benzo[1, 4]oxazin-4-yl)-ethoxy]-
phenylg-2-ethoxypropionic acid (36)
14.65 Hz); 3.11 (dd, 1H, J ¼ 4.25 Hz, 14.65 Hz), 3.71 (m, 1H); 4.00 (m,
1H); 4.20 (dd, 1H, J ¼ 4.25 Hz, 7.8 Hz); 4.31 (t, 2H, J ¼ 5.1 Hz); 4.40 (t,
2H, J ¼ 5.1 Hz); 6.74 (d, 2H, J ¼ 8.65 Hz); 7.13 (d, 2H, J ¼ 8.65 Hz);
7.38 (d, 1H, J ¼ 8.55 Hz); 7.51 (t, 2H, J ¼ 7.45 Hz); 7.62 (t, 1H,
J ¼ 7.45 Hz); 7.78 (d, 2H, J ¼ 7.45 Hz); 7.85 (dd, 1H, J ¼ 1.7 Hz,
8.55 Hz); 7.92 (d, 1H, J ¼ 1.7 Hz); 13 C NMR (75 MHz, CDCl3): d 37.7,
Off-white solid; 76% yield; C28H27NO7; MW ¼ 489.51 g/mol; m.p.
36–38 ꢁC. 1H NMR (CDCl3): d 1.17 (t, 3H, J ¼ 7 Hz); 2.95 (dd, 1H,
J ¼ 7.75 Hz, 14.25 Hz); 3.06 (dd, 1H, J ¼ 4.5 Hz, 14.25 Hz); 3.43 (m,
1H), 3.62 (m, 1H), 4.03 (dd, 1H, J ¼ 4.5 Hz, 7.75 Hz); 4.29 (t, 2H,
J ¼ 4.9 Hz); 4.38 (t, 2H, J ¼ 4.9 Hz); 4.68 (s, 2H); 6.79 (d, 2H,
42.9, 65.4, 68.05 (q, JC-F ¼ 34.8 Hz), 77.2, 80.7, 111.0, 114.2, 122.6, J ¼ 8.65 Hz); 7.16 (d, 2H, J ¼ 8.65 Hz); 7.44 (d, 1H, J ¼ 8.4 Hz);
7.48–7.53 (m, 3H); 7.57 (dd, 1H, J ¼ 1.9 Hz, 8.4 Hz); 7.61 (t, 1H,
124.9, 128.4, 128.6, 129.0, 129.9, 130.6, 132.5, 132.6, 137.5, 140.9,
J ¼ 7.6 Hz); 7.90 (dd, 2H, J ¼ 1.6 Hz, 8.4 Hz); 13 C NMR (75 MHz,
CDCl3): d 15.0, 37.8, 42.0, 65.0, 66.7, 67.5, 79.6, 114.2, 114.4,
115.6,118.8, 125.4, 128.3, 129.8, 130.6, 132.4, 132.9, 133.3, 137.4,
144.8, 157.0, 164.7, 175.4, 195.0. tR,LCMS ¼ 2.34 min; MS (ESIþ) m/z
490.3 [M þ H]þ. Anal. Calcd (%) for C28H27NO7: C, 68.70; H, 5.56; N,
2.86; found C, 68.54; H, 5.63; N, 2.57.
157.0, 170.5, 173.9, 195.3. tR,LCMS ¼ 2.50 min; MS (ESIþ) m/z 546.3
[M þ H]þ. Anal. Calcd (%) for C27H22F3NO6S: C, 59.45; H, 4.06; N,
2.57; found C, 59.56; H, 3.98; N, 2.49.
2.1.40. 3-f4-[2–(6-benzoyl-3-oxo-benzo[1, 4]thiazin-4-yl)-ethoxy]-
phenylg-2-ethoxypropionic acid (33)
Pale yellow solid; 78% yield; C28H27NO6S; MW¼ 505.59 g/mol; m.p.
52–54 ꢁC. 1H NMR (CDCl3): d 1.16 (t, 3H, J ¼ 7 Hz); 2.92 (dd, 1H,
J ¼ 7.5 Hz, 14.2 Hz); 3.06 (dd, 1H, J ¼ 4.25 Hz, 14.2 Hz); 3.45 (m, 3H);
3.58 (m, 1H); 4.03 (dd, 1H, J ¼ 4.25 Hz, 7.5 Hz); 4.28 (t, 2H,
J ¼ 4.6 Hz); 4.35 (t, 2H, J ¼ 4.6 Hz); 6.69 (d, 2H, J ¼ 8.7 Hz); 7.11 (d,
2H, J ¼ 8.7 Hz); 7.46–7.52 (m, 4H); 7.61 (t, 1H, J ¼ 7.7 Hz); 7.82 (d,
2H, J ¼ 7.3 Hz); 8.22 (d, 1H, J ¼ 1.5 Hz); 13 C NMR (75 MHz, CDCl3): d
15.0, 31.4, 37.7, 46.8, 65.6, 66.8, 79.7, 114.3, 120.7, 125.4, 127.7,
128.4, 129.1, 129.8, 129.9, 130.5, 132.7, 136.6, 137.3, 140.5, 157.1,
164.9, 174.0, 195.4. tR,LCMS ¼ 2.42 min; MS (ESIþ) m/z 506.3
[M þ H]þ. Anal. Calcd (%) for C28H27NO6S: C, 66.52; H, 5.38; N, 2.77;
found C, 66.88; H, 5.74; N, 2.51.
2.1.44. 3-f4-[2–(5-benzoyl-2-oxo-2,3-dihydroindol-1-yl)ethoxy]phenylg-
2-ethoxypropionic acid (37)
Pale yellow solid; 73% yield; C28H27NO6; MW ¼ 473.51 g/mol; m.p.
68–70 ꢁC. 1H NMR (CDCl3): d 1.18 (t, 3H, J ¼ 6.95 Hz); 2.63 (s, 2H);
2.95 (dd, 1H, J ¼ 7.05 Hz, 14.1 Hz); 3.07 (dd, 1H, J ¼ 4.3 Hz, 14.1 Hz);
3.48 (m, 1H); 3.59 (m, 1H); 4.05 (dd, 1H, J ¼ 4.03 Hz, 7.05 Hz); 4.20
(t, 2H, J ¼ 5.05 Hz); 4.28 (t, 2H, J ¼ 5.05 Hz); 6.75 (d, 2H, J ¼ 8.65 Hz);
7.14 (d, 2H, J ¼ 8.65 Hz); 7.33 (d, 1H, J ¼ 8.4 Hz); 7.52 (t, 2H,
J ¼ 7.65 Hz); 7.64 (t, 1H, J ¼ 7.2 Hz); 7.75 (d, 2H, J ¼ 7.95 Hz); 8.01 (d,
1H, J ¼ 1.8 Hz); 8.24 (dd, 1H, J ¼ 1.8 Hz, 8.4 Hz); 13 C NMR (75 MHz,
CDCl3): d 15.1, 37.4, 40.5, 40.8, 65.72, 66.9, 79.5, 111.4, 114.2,
116.8, 127.2, 128.6, 129.4, 129.6, 130.7, 132.8, 136.9, 140.3, 154.4,
156.8, 158.5, 172.8, 182.2, 194.2. tR,LCMS ¼ 2.25 min; MS (ESIþ) m/z
474.3 [M þ H]þ. Anal. Calcd (%) for C28H27NO6: C, 71.02; H, 5.75; N,
2.96; found C, 71.19; H, 5.59; N, 2.90.
2.1.41. 3-f4-[2–(7-benzoyl-3-oxo-benzo[1, 4]thiazin-4-yl)-ethoxy]-
phenylg-2-ethoxypropionic acid (34)
Off-white solid; 79% yield; C28H27NO6S; MW ¼ 505.59 g/mol; m.p.
58–60 ꢁC. 1H NMR (CDCl3): d 1.18 (t, 3H, J ¼ 6.95 Hz); 2.95 (dd, 1H,
J ¼ 7.45 Hz, 14.5 Hz); 3.08 (dd, 1H, J ¼ 4.4 Hz, 14.5 Hz); 3.45 (m, 3H);
3.60 (m, 1H); 4.04 (dd, 1H, J ¼ 4.4 Hz, 7.45 Hz); 4.32 (t, 2H, J ¼ 5 Hz);
4.39 (t, 2H, J ¼ 5 Hz); 6.81 (d, 2H, J ¼ 8.6 Hz); 7.15 (d, 2H, J ¼ 8.6 Hz);
7.51 (t, 2H, J ¼ 7.75 Hz); 7.62 (t, 1H, J ¼ 7.45 Hz); 7.68 (d, 1H,
J ¼ 8.7 Hz); 7.74 (dd, 1H, J ¼ 2 Hz, 8.7 Hz); 7.79 (d, 2H, J ¼ 8.25 Hz);
7.85 (d, 1H, J ¼ 2 Hz); 13 C NMR (75 MHz, CDCl3): d 15.0, 31.3, 37.6,
46.3, 65.3; 66.8, 79.6, 114.3, 118.6, 124.0, 128.4, 129.2, 129.4, 129.8,
130.1, 130.6, 132.6, 132.7, 137.3, 143.4, 157.1, 165.1, 173.9, 194.8.
tR,LCMS ¼ 2.44 min; MS (ESIþ) m/z 506.3 [M þ H]þ. Anal. Calcd (%)
for C28H27NO6S: C, 66.52; H, 5.38; N, 2.77; found C, 66.53; H, 5.31;
N, 2.54.
2.1.45. 3-f4-[2–(5-benzoyl-3,3-difluoro-2-oxo-2,3-dihydroindol-1-yl)
ethoxy]phenylg-2-ethoxy-propionic acid (38)
Pale yellow solid; 84% yield; C28H25F2NO6; MW ¼ 509.49 g/mol;
m.p. 78–79 ꢁC. 1H NMR (CDCl3): d 1.14 (t, 3H, J ¼ 6.95 Hz); 2.92 (dd,
1H, J ¼ 7.35 Hz, 14.05 Hz); 3.05 (dd, 1H, J ¼ 4.35 Hz, 14.05 Hz); 3.43
(m, 1H); 3.59 (m, 1H); 4.01 (dd, 1H, J ¼ 4.35 Hz, 7.35 Hz); 4.15 (t, 2H,
J ¼ 4.9 Hz); 4.24 (t, 2H, J ¼ 4.9 Hz); 6.73 (d, 2H, J ¼ 8.65 Hz); 7.13 (d,
2H, J ¼ 8.65 Hz); 7.29 (m, 1H); 7.52 (t, 2H, J ¼ 7.95 Hz); 7.63 (t, 1H,
J ¼ 7.3 Hz); 7.77 (d, 2H, J ¼ 6.9 Hz); 8.01 (d, 1H, J ¼ 1.8 Hz); 8.06 (dd,
1H, J ¼ 1.8 Hz, 8.55 Hz); 13 C NMR (75 MHz, CDCl3): d 15.0, 37.6,
40.6, 65.4, 66.7, 79.8, 110.0, 110.6, 114.2, 119.9, 126.6, 128.5, 129.7,
130.6, 132.7, 133.4, 136.2, 137.1, 147.4, 156.7, 165.7, 174.6, 194.4.
tR,LCMS ¼ 2.49 min; MS (ESIþ) m/z 510.3 [M þ H]þ. Anal. Calcd (%)

530
A. HURTEVENT ET AL.
for C28H25F2NO6: C, 66.01; H, 4.95; N, 2.75; found C, 66.22; H, 5.01; 129.5, 129.8, 130.6, 132.4, 132.6, 137.6, 140.9, 156.8, 170.4, 175.1,
195.1153. tR,LCMS ¼ 2.45 min; MS (ESIþ) m/z 492.3 [M þ H]þ. Chiral
N, 2.69.
HPLC method: flow rate ¼ 1.5 mL/min, eluents ¼ A/B 2:8, tr
¼ 22.38 min.
2.1.46. General procedure for synthesis of optically pure carboxylic
acids (41a,b and 42a,b)
2.1.50.
(R)-3-f4-[2–(6-benzoyl-2-oxo-benzothiazol-3-yl)-ethoxy]-
A solution of 2 (0.5 g, 2 mmol, 1.0 eq) in HMPA (5 mL) was added
dropwise to a 60% NaH dispersion in mineral oil (0.12 g, 3 mmol,
1.5 eq) in HMPA (5 mL) at 0 ꢁC under N2, and the solution was
stirred for 30 min at room temperature. A solution of 21a or 22a
(0.66 g, 2.4 mmol, 1.2 eq) or 21 b or 22 b (0.78 g, 2.4 mmol, 1.2 eq)
in HMPA (5 mL) was then added, and the mixture was stirred at
room temperature for 12 h under N2. The reaction mixture was
hydrolysed with 1 M aqueous HCl solution, and the precipitate
was filtered off, dried and purified by flash column chromatog-
raphy (DCM/MeOH 95:5).
phenylg-2–(2,2,2-trifluoro)ethoxy-propionic acid (42 b)
Off-white solid; 74% yield; C27H22F3NO6S; MW¼ 545.52 g/mol; m.p.
1
60–62 ꢁC. H NMR (CDCl3): d 2.99 (dd, 1H, J ¼ 7.8 Hz, 14.65 Hz); 3.11
(dd, 1H, J ¼ 4.25 Hz, 14.65 Hz), 3.71 (m, 1H); 4.00 (m, 1H); 4.20 (dd,
1H, J ¼ 4.25 Hz, 7.8 Hz); 4.31 (t, 2H, J ¼ 5.1 Hz); 4.40 (t, 2H,
J ¼ 5.1 Hz); 6.74 (d, 2H, J ¼ 8.65 Hz); 7.13 (d, 2H, J ¼ 8.65 Hz); 7.38
(d, 1H, J ¼ 8.55 Hz); 7.51 (t, 2H, J ¼ 7.45 Hz); 7.62 (t, 1H, J ¼ 7.45 Hz);
7.78 (d, 2H, J ¼ 7.45 Hz); 7.85 (dd, 1H, J ¼ 1.7 Hz, 8.55 Hz); 7.92 (d,
1H, J ¼ 1.7 Hz); 13 C NMR (75 MHz, CDCl3): d 37.7, 42.9, 65.4, 68.05
(q, JC–F ¼ 34.8 Hz), 77.2, 80.7, 111.0, 114.2, 122.6, 124.9, 128.4,
128.6, 129.0, 129.9, 130.6, 132.5, 132.6, 137.5, 140.9, 157.0, 170.5,
173.9, 195.3. tR,LCMS ¼ 2.50 min; MS (ESIþ) m/z 546.3 [M þ H]þ.
Chiral HPLC method: flow rate ¼ 1.5 mL/min, eluents ¼ A/B 2:8, tr
¼ 17.10 min.
2.1.47.
(S)-3-f4-[2–(6-benzoyl-2-oxo-benzothiazol-3-yl)-ethoxy]-
phenylg-2-ethoxypropionic acid (41a)
Off-White solid; 79% yield; C27H25NO6S; MW¼ 491.57 g/mol; m.p.
57–59 ꢁC. 1H NMR (CDCl3): d 1.16 (t, 3H, J ¼ 6.95 Hz); 2.93 (dd, 1H,
J ¼ 7.55 Hz, 14.05 Hz); 3.04 (dd, 1H, J ¼ 4.4 Hz, 14.05 Hz); 3.41 (m,
1H); 3.60 (m, 1H); 4.02 (dd, 1H, J ¼ 4.4 Hz, 7.65 Hz); 4.30 (t, 2H,
J ¼ 5.45 Hz); 4.40 (t, 2H, J ¼ 5.45 Hz); 6.74 (d, 2H, J ¼ 8.5 Hz); 7.13 (d,
2H, J ¼ 8.5 Hz); 7.41 (d, 1H, J ¼ 8.6 Hz); 7.51 (t, 2H, J ¼ 7.8 Hz); 7.62
(t, 1H, J ¼ 7.5 Hz); 7.78 (d, 2H, J ¼ 8 Hz); 7.86 (dd, 1H, J ¼ 1.8 Hz,
8.5 Hz); 7.92 (d, 1H, J ¼ 1.8 Hz). 13 C NMR (75 MHz, CDCl3): d 15.0,
37.7, 42.9, 65.5, 66.7, 79.6, 111.1, 114.2, 122.6, 124.8, 128.4, 129.0,
129.5, 129.8, 130.6, 132.4, 132.6, 137.6, 140.9, 156.8, 170.4, 175.1,
195.1153. tR,LCMS ¼ 2.45 min; MS (ESIþ) m/z 492.3 [M þ H]þ. Chiral
HPLC method: flow rate¼ 1.5 mL/min, eluents ¼ A/B 2:8, tr
¼ 25.44 min.
2.1.51. General procedure for the synthesis of oxime 39a,b, 43a,
45a and O-methyl oxime ethers 40a,b, 44a,b, 46a,b
Hydroxylamine hydrochloride (0.69 g, 10 mmol, 4.0 eq) or O-meth-
ylhydroxylamine hydrochloride (0.83 g, 10 mmol, 4 equiv) was
added to a solution of 32a,b, 41a,b or 42a,b (2.5 mmol, 1.0 eq) in
pyridine (20 mL), and the mixture was stirred at 100 ꢁC for 4 h. The
reaction mixture was concentrated in vacuo, hydrolysed with 1 M
aqueous HCl solution, and extracted twice with DCM. The com-
bined organic extracts were dried over MgSO4, filtered off, evapo-
rated under reduced pressure, and the resulting residues were
purified by flash column chromatography (toluene/EtOAc 97:3).
2.1.48.
(S)-3-f4-[2–(6-benzoyl-2-oxo-benzothiazol-3-yl)-ethoxy]-
phenylg-2–(2,2,2-trifluoro)ethoxy-propionic acid (41 b)
2.1.52. 3-f4-[2–(6-[(E)-hydroxyimino-phenyl-methyl]-2-oxo-benzo-
thiazol-3-yl)-ethoxy]-phenylg-2-ethoxypropionic acid (39a)
Off-white solid; 76% yield; C27H22F3NO6S; MW¼ 545.52 g/mol; m.p.
1
60–62 ꢁC. H NMR (CDCl3): d 2.99 (dd, 1H, J ¼ 7.8 Hz, 14.65 Hz); 3.11
Off-white solid; 76% yield; C27H26N2O6S; MW¼ 506.57 g/mol; m.p.
84–85 ꢁC. 1H NMR (CDCl3): d 1.17 (t, 3H, J ¼ 6.9 Hz); 2.95 (dd, 1H,
J ¼ 7.5 Hz, 14.2 Hz); 3.06 (dd, 1H, J ¼ 4.5 Hz, 14.2 Hz); 3.43 (m, 1H);
3.61 (m, 1H); 4.04 (dd, 1H, J ¼ 4.5 Hz, 7.5 Hz); 4.28 (t, 2H, J ¼ 4.7 Hz);
4.35 (t, 2H, J ¼ 4.7 Hz); 6.76 (d, 2H, J ¼ 8.6 Hz); 7.14 (d, 2H,
J ¼ 8.6 Hz); 7.30 (d, 1H, J ¼ 8.45 Hz); 7.39–7.52 (m, 7H); 13 C NMR
(75 MHz, CDCl3): d 15.0, 37.8, 42.7, 65.5, 66.7, 79.7, 111.4, 114.2,
122.2, 122.7, 126.0, 128.4, 129.3, 129.4, 129.5, 130.6, 131.4, 132.1,
138.6, 156.9, 157.1, 170.3, 174.8. tR,LCMS ¼ 2.25 min; MS (ESIþ) m/z
507.3 [M þ H]þ. Anal. Calcd (%) for C27H26N2O6S: C, 64.02; H, 5.17;
N, 5.53; found C, 64.21; H, 5.21; N, 5.44.
(dd, 1H, J ¼ 4.25 Hz, 14.65 Hz), 3.71 (m, 1H); 4.00 (m, 1H); 4.20 (dd,
1H, J ¼ 4.25 Hz, 7.8 Hz); 4.31 (t, 2H, J ¼ 5.1 Hz); 4.40 (t, 2H,
J ¼ 5.1 Hz); 6.74 (d, 2H, J ¼ 8.65 Hz); 7.13 (d, 2H, J ¼ 8.65 Hz); 7.38
(d, 1H, J ¼ 8.55 Hz); 7.51 (t, 2H, J ¼ 7.45 Hz); 7.62 (t, 1H, J ¼ 7.45 Hz);
7.78 (d, 2H, J ¼ 7.45 Hz); 7.85 (dd, 1H, J ¼ 1.7 Hz, 8.55 Hz); 7.92 (d,
1H, J ¼ 1.7 Hz); 13 C NMR (75 MHz, CDCl3): d 37.7, 42.9, 65.4, 68.05
(q, JC–F ¼ 34.8 Hz), 77.2, 80.7, 111.0, 114.2, 122.6, 124.9, 128.4,
128.6, 129.0, 129.9, 130.6, 132.5, 132.6, 137.5, 140.9, 157.0, 170.5,
173.9, 195.3. tR,LCMS ¼ 2.50 min; MS (ESIþ) m/z 546.3 [M þ H]þ.
Chiral HPLC method: flow rate¼ 1.5 mL/min, eluents ¼ A/B 2:8, tr
¼ 22.36 min.
2.1.53. 3-f4-[2–(6-[(Z/E)-hydroxyimino-phenyl-methyl]-2-oxo-ben-
zothiazol-3-yl)-ethoxy]-phenylg-2–(2,2,2-trifluoro)ethoxypropionic
acid (39 b)
2.1.49.
(R)-3-f4-[2–(6-benzoyl-2-oxo-benzothiazol-3-yl)-ethoxy]-
phenylg-2-ethoxypropionic acid (42a)
Off-White solid; 72% yield; C27H25NO6S; MW¼ 491.57 g/mol; m.p.
57–59 ꢁC. 1H NMR (CDCl3): d 1.16 (t, 3H, J ¼ 6.95 Hz); 2.93 (dd, 1H,
J ¼ 7.55 Hz, 14.05 Hz); 3.04 (dd, 1H, J ¼ 4.4 Hz, 14.05 Hz); 3.41 (m,
1H); 3.60 (m, 1H); 4.02 (dd, 1H, J ¼ 4.4 Hz, 7.65 Hz); 4.30 (t, 2H,
J ¼ 5.45 Hz); 4.40 (t, 2H, J ¼ 5.45 Hz); 6.74 (d, 2H, J ¼ 8.5 Hz); 7.13 (d,
2H, J ¼ 8.5 Hz); 7.41 (d, 1H, J ¼ 8.6 Hz); 7.51 (t, 2H, J ¼ 7.8 Hz); 7.62
(t, 1H, J ¼ 7.5 Hz); 7.78 (d, 2H, J ¼ 8 Hz); 7.86 (dd, 1H, J ¼ 1.8 Hz,
8.5 Hz); 7.92 (d, 1H, J ¼ 1.8 Hz). 13 C NMR (75 MHz, CDCl3): d 15.0,
Off-white solid; 74% yield; C27H23F3N2O6S; MW ¼ 560.54 g/mol;
m.p. 55–56 ꢁC. 1H NMR (CDCl3): d 3.06 (m, 2H); 3.69 (m, 1H); 4.01
(m, 1H); 4.21 (m, 1H); 4.28–4.39 (m, 4H); 5.67 (br s, 1H); 6.75 (m,
2H); 7.15 (m, 2H); 7.35–7.62 (m, 7H); 7.77–7.92 (m, 1H); 13 C NMR
(75 MHz, CDCl3): d 37.9, 42.7, 65.4, 67.2, 67.7, 68.1, 68.4, 68.6, 80.9,
111.0, 111.4, 114.2, 114.3, 122.3, 122.5, 123.9, 124.9, 126.0, 128.2,
128.4, 128.5, 129.4, 129.8, 129.9, 130.6, 135.7, 137.5, 138.2, 138.7,
37.7, 42.9, 65.5, 66.7, 79.6, 111.1, 114.2, 122.6, 124.8, 128.4, 129.0, 140.9, 157.0, 170.3, 174.5. tR,LCMS ¼ 2.32 min; MS (ESIþ) m/z 561.3

JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY
531
[M þ H]þ. Anal. Calcd (%) for C27H23F3N2O6S: C, 57.85; H, 5.14; N, 174.1. tR,LCMS ¼ 2.7 min; MS (ESIþ) m/z 521.3 [M þ H]þ. Chiral HPLC
5.00; found C, 57.95; H, 5.03; N, 5.12.
method: flow rate¼ 1 mL/min, eluents ¼ A/B 2:8, tr ¼ 16.05 min.
2.1.54. 3-f4-[2–(6-[(E)-methoxyimino-phenyl-methyl]-2-oxo-benzo- 2.1.58. (S)-3-f4-[2–(6-[(E)-methoxyimino-phenyl-methyl]-2-oxo-ben-
thiazol-3-yl)-ethoxy]-phenylg-2-ethoxypropionic acid (40a)
Off-white solid; 73% yield; C28H28N2O6S; MW¼ 520.59 g/mol; m.p.
151–152 ꢁC. 1H NMR (CDCl3): d 1.18 (t, 3H, J ¼ 7 Hz); 2.94 (dd, 1H,
J ¼ 7.6 Hz, 14.4 Hz); 3.07 (dd, 1H, J ¼ 4.3 Hz, 14.4 Hz); 3.46 (m, 1H);
3.60 (m, 1H); 4.00 (s, 3H); 4.04 (dd, 1H, J ¼ 4.3 Hz, 7.6 Hz); 4.28 (t,
2H, J ¼ 5 Hz); 4.35 (t, 2H, J ¼ 5 Hz); 6.75 (d, 2H, J ¼ 8.8 Hz); 7.13 (d,
2H, J ¼ 8.8 Hz); 7.25 (d, 1H, J ¼ 8.6 Hz); 7.36 (m, 2H); 7.44–7.51 (m,
4H); 7.57 (d, 1H, J ¼ 1.7 Hz); 13C NMR (75 MHz, CDCl3): d 15.0, 37.6,
42.7, 62.5, 65.4, 66.9, 79.6, 111.1, 114.2, 121.8, 122.6, 126.1, 128.3,
129.1, 129.1, 129.2, 130.6, 131.8, 132.9, 138.3, 155.8, 157.0, 170.4,
174.1. tR,LCMS ¼ 2.7 min; MS (ESIþ) m/z 521.3 [M þ H]þ. Anal. Calcd
(%) for C28H28N2O6S: C, 64.60; H, 5.42; N, 5.38; found C, 64.71; H,
5.31; N, 5.46.
zothiazol-3-yl)-ethoxy]-phenylg-2–(2,2,2-trifluoro)ethoxypropionic
acid (44 b)
Off-white solid; 81% yield; C28H25F3N2O6S; MW¼ 574.56 g/mol;
m.p. 56–57 ꢁC. 1H NMR (CDCl3): d 3.01 (dd, 1H, J ¼ 7.65 Hz,
14.4 Hz); 3.13 (dd, 1H, J ¼ 4.15 Hz, 14.4 Hz); 3.73 (m, 1H), 4.00 (m,
4H), 4.22 (dd, 1H, J ¼ 4.15 Hz, 7.65 Hz); 4.30 (t, 2H, J ¼ 4.3 Hz); 4.35
(t, 2H, J ¼ 4.3 Hz); 6.75 (d, 2H, J ¼ 8.7 Hz); 7.13 (d, 2H, J ¼ 8.7 Hz);
7.24 (d, 1H, J ¼ 8.7 Hz); 7.37 (m, 2H); 7.44–7.51 (m, 4H); 7.57 (d, 1H,
J ¼ 1.7 Hz); 13 C NMR (75 MHz, CDCl3): d 37.8, 42.7, 62.5, 65.3, 68.0
(q, JC–F ¼ 34.45 Hz), 77.2, 80.8, 111.0, 114.3, 121.9, 122.6, 126.1,
128.0, 128.3, 128.3, 128.5, 129.1, 130.6, 131.7, 132.9, 138.3, 155.9,
157.1, 170.4, 173.9. tR,LCMS ¼ 2.67 min; MS (ESIþ) m/z 575.3
[M þ H]þ. Chiral HPLC method: flow rate¼ 1 mL/min, eluents ¼ A/B
15:85, tr ¼ 22.02 min.
2.1.55. 3-f4-[2–(6-[(E)-methoxyimino-phenyl-methyl]-2-oxo-benzo-
thiazol-3-yl)-ethoxy]-phenylg-2–(2,2,2-trifluoro)ethoxypropionic
acid (40 b)
2.1.59. (R)-3-f4-[2–(6-[(E)-hydroxyimino-phenyl-methyl]-2-oxo-ben-
zothiazol-3-yl)-ethoxy]-phenylg-2-ethoxypropionic acid (45a)
Off-white solid; 72% yield; C27H26N2O6S; MW¼ 506.57 g/mol; m.p.
84–85 ꢁC. 1H NMR (CDCl3): d 1.17 (t, 3H, J ¼ 6.9 Hz); 2.95 (dd, 1H,
J ¼ 7.5 Hz, 14.2 Hz); 3.06 (dd, 1H, J ¼ 4.5 Hz, 14.2 Hz); 3.43 (m, 1H);
3.61 (m, 1H); 4.04 (dd, 1H, J ¼ 4.5 Hz, 7.5 Hz); 4.28 (t, 2H, J ¼ 4.7 Hz);
4.35 (t, 2H, J ¼ 4.7 Hz); 6.76 (d, 2H, J ¼ 8.6 Hz); 7.14 (d, 2H,
J ¼ 8.6 Hz); 7.30 (d, 1H, J ¼ 8.45 Hz); 7.39–7.52 (m, 7H); 13 C NMR
(75 MHz, CDCl3): d 15.0, 37.8, 42.7, 65.5, 66.7, 79.7, 111.4, 114.2,
122.2, 122.7, 126.0, 128.4, 129.3, 129.4, 129.5, 130.6, 131.4, 132.1,
138.6, 156.9, 157.1, 170.3, 174.8. tR,LCMS ¼ 2.25 min; MS (ESIþ) m/z
507.3 [M þ H]þ. Chiral HPLC method: flow rate ¼ 1.5 mL/min,
eluents ¼ A/B 2:8, tr ¼ 29.42 min.
Off-white solid; 81% yield; C28H25F3N2O6S; MW ¼ 574.56 g/mol;
m.p. 56–57 ꢁC. 1H NMR (CDCl3): d 3.01 (dd, 1H, J ¼ 7.65 Hz,
14.4 Hz); 3.13 (dd, 1H, J ¼ 4.15 Hz, 14.4 Hz); 3.73 (m, 1H), 4.00 (m,
4H), 4.22 (dd, 1H, J ¼ 4.15 Hz, 7.65 Hz); 4.30 (t, 2H, J ¼ 4.3 Hz); 4.35
(t, 2H, J ¼ 4.3 Hz); 6.75 (d, 2H, J ¼ 8.7 Hz); 7.13 (d, 2H, J ¼ 8.7 Hz);
7.24 (d, 1H, J ¼ 8.7 Hz); 7.37 (m, 2H); 7.44–7.51 (m, 4H); 7.57 (d, 1H,
J ¼ 1.7 Hz); 13 C NMR (75 MHz, CDCl3): d 37.8, 42.7, 62.5, 65.3, 68.0
(q, JC–F ¼ 34.45 Hz), 77.2, 80.8, 111.0, 114.3, 121.9, 122.6, 126.1,
128.0, 128.3, 128.3, 128.5, 129.1, 130.6, 131.7, 132.9, 138.3, 155.9,
157.1, 170.4, 173.9. tR,LCMS ¼ 2.67 min; MS (ESIþ) m/z 575.3
[M þ H]þ. Anal. Calcd (%) for C28H25F3N2O6S: C, 58.53; H, 4.39; N,
4.88; found C, 58.69; H, 4.25; N, 4.78.
2.1.60. (R)-3-f4-[2–(6-[(E)-methoxyimino-phenyl-methyl]-2-oxo-ben-
zothiazol-3-yl)-ethoxy]-phenylg-2-ethoxypropionic acid (46a)
Off-white solid; 75% yield; C28H28N2O6S; MW¼ 520.59 g/mol; m.p.
151–152 ꢁC. 1H NMR (CDCl3): d 1.18 (t, 3H, J ¼ 7 Hz); 2.94 (dd, 1H,
J ¼ 7.6 Hz, 14.4 Hz); 3.07 (dd, 1H, J ¼ 4.3 Hz, 14.4 Hz); 3.46 (m, 1H);
3.60 (m, 1H); 4.00 (s, 3H); 4.04 (dd, 1H, J ¼ 4.3 Hz, 7.6 Hz); 4.28 (t,
2H, J ¼ 5 Hz); 4.35 (t, 2H, J ¼ 5 Hz); 6.75 (d, 2H, J ¼ 8.8 Hz); 7.13 (d,
2H, J ¼ 8.8 Hz); 7.25 (d, 1H, J ¼ 8.6 Hz); 7.36 (m, 2H); 7.44–7.51 (m,
4H); 7.57 (d, 1H, J ¼ 1.7 Hz); 13 C NMR (75 MHz, CDCl3): d 15.0, 37.6,
42.7, 62.5, 65.4, 66.9, 79.6, 111.1, 114.2, 121.8, 122.6, 126.1, 128.3,
129.1, 129.1, 129.2, 130.6, 131.8, 132.9, 138.3, 155.8, 157.0, 170.4,
174.1. tR,LCMS ¼ 2.7 min; MS (ESIþ) m/z 521.3 [M þ H]þ. Chiral HPLC
method: flow rate¼ 1 mL/min, eluents ¼ A/B 2:8, tr ¼ 13.51 min.
2.1.56. (S)-3-f4-[2–(6-[(E)-hydroxyimino-phenyl-methyl]-2-oxo-ben-
zothiazol-3-yl)-ethoxy]-phenylg-2-ethoxypropionic acid (43a)
Off-white solid; 78% yield; C27H26N2O6S; MW¼ 506.57 g/mol; m.p.
84–85 ꢁC. 1H NMR (CDCl3): d 1.17 (t, 3H, J ¼ 6.9 Hz); 2.95 (dd, 1H,
J ¼ 7.5 Hz, 14.2 Hz); 3.06 (dd, 1H, J ¼ 4.5 Hz, 14.2 Hz); 3.43 (m, 1H);
3.61 (m, 1H); 4.04 (dd, 1H, J ¼ 4.5 Hz, 7.5 Hz); 4.28 (t, 2H, J ¼ 4.7 Hz);
4.35 (t, 2H, J ¼ 4.7 Hz); 6.76 (d, 2H, J ¼ 8.6 Hz); 7.14 (d, 2H,
J ¼ 8.6 Hz); 7.30 (d, 1H, J ¼ 8.45 Hz); 7.39–7.52 (m, 7H); 13 C NMR
(75 MHz, CDCl3): d 15.0, 37.8, 42.7, 65.5, 66.7, 79.7, 111.4, 114.2,
122.2, 122.7, 126.0, 128.4, 129.3, 129.4, 129.5, 130.6, 131.4, 132.1,
138.6, 156.9, 157.1, 170.3, 174.8. tR,LCMS ¼ 2.25 min; MS (ESIþ) m/z
507.3 [M þ H]þ. Chiral HPLC method: flow rate ¼ 1.5 mL/min,
eluents ¼ A/B 2:8, tr ¼ 32.19 min.
2.1.61. (R)-3-f4-[2–(6-[(E)-methoxyimino-phenyl-methyl]-2-oxo-ben-
zothiazol-3-yl)-ethoxy]-phenylg-2–(2,2,2-trifluoro)ethoxypropionic
acid (46 b)
Off-white solid; 74% yield; C28H25F3N2O6S; MW¼ 574.56 g/mol;
2.1.57. (S)-3-f4-[2–(6-[(E)-methoxyimino-phenyl-methyl]-2-oxo-ben-
zothiazol-3-yl)-ethoxy]-phenylg-2-ethoxypropionic acid (44a)
Off-white solid; 79% yield; C28H28N2O6S; MW ¼ 520.59 g/mol; m.p.
151–152 ꢁC. 1H NMR (CDCl3): d 1.18 (t, 3H, J ¼ 7 Hz); 2.94 (dd, 1H, m.p. 56–57 ꢁC. 1H NMR (CDCl3): d 3.01 (dd, 1H, J ¼ 7.65 Hz,
J ¼ 7.6 Hz, 14.4 Hz); 3.07 (dd, 1H, J ¼ 4.3 Hz, 14.4 Hz); 3.46 (m, 1H); 14.4 Hz); 3.13 (dd, 1H, J ¼ 4.15 Hz, 14.4 Hz); 3.73 (m, 1H), 4.00 (m,
3.60 (m, 1H); 4.00 (s, 3H); 4.04 (dd, 1H, J ¼ 4.3 Hz, 7.6 Hz); 4.28 (t, 4H), 4.22 (dd, 1H, J ¼ 4.15 Hz, 7.65 Hz); 4.30 (t, 2H, J ¼ 4.3 Hz); 4.35
2H, J ¼ 5 Hz); 4.35 (t, 2H, J ¼ 5 Hz); 6.75 (d, 2H, J ¼ 8.8 Hz); 7.13 (d, (t, 2H, J ¼ 4.3 Hz); 6.75 (d, 2H, J ¼ 8.7 Hz); 7.13 (d, 2H, J ¼ 8.7 Hz);
2H, J ¼ 8.8 Hz); 7.25 (d, 1H, J ¼ 8.6 Hz); 7.36 (m, 2H); 7.44–7.51 (m, 7.24 (d, 1H, J ¼ 8.7 Hz); 7.37 (m, 2H); 7.44–7.51 (m, 4H); 7.57 (d, 1H,
4H); 7.57 (d, 1H, J ¼ 1.7 Hz); 13 C NMR (75 MHz, CDCl3): d 15.0, 37.6, J ¼ 1.7 Hz); 13 C NMR (75 MHz, CDCl3): d 37.8, 42.7, 62.5, 65.3, 68.0
42.7, 62.5, 65.4, 66.9, 79.6, 111.1, 114.2, 121.8, 122.6, 126.1, 128.3, (q, JC-F ¼ 34.45 Hz), 77.2, 80.8, 111.0, 114.3, 121.9, 122.6, 126.1,
129.1, 129.1, 129.2, 130.6, 131.8, 132.9, 138.3, 155.8, 157.0, 170.4, 128.0, 128.3, 128.3, 128.5, 129.1, 130.6, 131.7, 132.9, 138.3, 155.9,

532
A. HURTEVENT ET AL.
157.1, 170.4, 173.9. tR,LCMS ¼ 2.67 min; MS (ESIþ) m/z 575.3 respectively WY 14,643 and rosiglitazone (positive controls) were
[M þ H]þ. Chiral HPLC method: flow rate¼ 1 mL/min, eluents ¼ A/B considered full agonists. EC50 were estimated using Prism software
15:85, tr ¼ 15.61 min.
(GraphPad). All transfection experiments were performed at least
three times.
2.2. Biological assay methods
2.2.3. In vivo ob/ob mice
2.2.1. Membrane-bound PPARc binding assay
The glucose- and triglyceride-lowering activities of the compounds
prepared were then tested using 10–12-week-old male ob/ob
mice. The mice were housed in a temperature-controlled room
(21.0–24.0 ꢁC) at a relative humidity of 45–65%, and a 12 h light–-
dark cycle (light period 5:30–17:30). Mice had access to filtered
(0.22 mm) tap water ad libitum and irradiated pelleted laboratory
chow (transbreed, Special Diet Services, England) throughout the
study. Compounds were prepared as a suspension in 1% hydrox-
yethylcellulose (HEC) for oral administration (10 mLkgꢂ1). The
mice (n ¼ 8–12 per group) were dosed by gavage daily between
15:00 and 17:00 for 4 days. Randomisation was performed based
on glycaemia values. The body weight gain (DBW in grams) of the
animals was determined by measuring the difference between
body weight at the beginning and end of the study for each
mouse. At day 5 between 9:00 and 11:00 the mice were weighed,
and blood samples were collected into heparin-containing tubes
by retro-orbital puncture (500 mL per mouse). All procedures com-
plied with International European Ethical Standards (86/609-EEC),
Binding assays were performed in 96-well plates format, using a
classical filtration assay with a human full length PPARc construct
(GST-PPAR LBD (25 mg/mL)) expressed in bacteria with some modi-
fications regarding the conditions of the experiments. The mem-
brane-associated PPARc was used as the biological source as
previously described. Binding buffer consisted of 10 mM Tris/HCl,
pH 8.2, containing 50 mM KCl and 1 mM dithiothreitol. Membrane
preparations (5 mg/mL) were incubated for 180 min at 4 ꢁC in the
presence of [3H]rosiglitazone [BRL49653, Amersham] (4 nM) and
the tested compounds. Non-specific binding was defined using an
excess of unlabelled rosiglitazone (10 mM). Incubation was termi-
nated by the addition of ice cold 50 mM Tris/HCl buffer pH 7.4 fol-
lowed by rapid filtration under reduced pressure through
Whatman GF/C filter plates pre-soaked with ice-cold buffer, fol-
lowed by three successive washes with the same buffer.
Radioactivity was measured in a TopCount apparatus (Packard).
The receptor preparation used during these experiments pre-
sented a Bmax of 49 pmol/mg proteins and a Kd of 5.58 nM for
[3H]-rosiglitazone. The compounds were solubilised in pure DMSO
and diluted to the appropriate working concentrations (100 mM to
0.1 nM). For each compound tested, plots of ligand concentration
versus DPM of radioligand bound were constructed and apparent
Ki values were estimated from nonlinear least-squares fit of the
data assuming simple competitive binding. The details of this
assay have been reported18.
ꢀ
the French National Committee (decret 87/848) for the care and
use of laboratory animals and were approved by our institutional
ethical committee. Plasma samples were prepared by centrifuga-
tion (2000 g for 10 min), and stored at ꢂ20 ꢁC. For triglycerides
and insulin determination, the percent change in plasma level in
the treated group was calculated relative to the mean plasma
level in the vehicle-treated group. ANOVA, followed by Dunnett’s
comparison test (one-tailed) was used to estimate significant dif-
ferences between the plasma glycaemia, triglycerides, insulin, and
DBW values between the control group and the individual com-
pound-treated groups. The compound is considered active at the
specific dosage administered if the difference in plasma levels has
p < 0.05; all compounds with p > 0.05 were reported as inactive.
2.2.2. Gene reporter assays: cell culture and transfection
Cos-7 cells were transiently transfected with luciferase reporter
plasmid (pG5-TK-pGL3) in the presence of pGal4-hPPARa or pGal4-
hPPARc (these vectors express chimeric proteins containing the
Gal4 DNA-binding domain fused to the human PPARa or PPARc
ligand binding domain coding sequence) expression vector.
Plasmids pGal4-hPPARa and c pG5-TK-pGL3 were constructed as
described previously19. Cells were seeded in 60 mm dishes at a
density of 5.5 ꢀ 105 cells/dish in DMEM supplemented with 10%
FCS and incubated at 37 ꢁC for 24 h prior to transfection. Cells
were transfected in OptiMEM without FCS for 3 h at 37ꢁ, using
polyethylenimine (PEI), with reporter and expression plasmids, as
stated in figure’s legend. The plasmid pBluescript (Stratagene, La
Jolla, CA) was used as carrier DNA to set the final amount of DNA
to 5.5 mg/dish. The pCMV- ß-galactosidase expression plasmid was
cotransfected as a control for transfection efficiency. Transfection
was stopped by addition of DMEM supplemented with 10% FCS
and cells were then incubated at 37 ꢁC. After 16 h, cells were tryp-
sinised and seeded in 96-well plates at the density of 2 ꢀ 104
cells/well and incubated for 6 h in 10% FCS containing DMEM.
2.3. Molecular docking studies
The crystallographic data for PPARc co-crystallized with tesaglita-
zar were downloaded from the PDB data bank (http://www.rcsb.
org/-PDB code: 1I7I). The studied compounds were built using the
€
atomic partial charges calculated with the Gasteiger-Huckel
method and their geometry was optimised by the Powell method
available in the Maximin2 procedure to a gradient of 0.001 Kcal/
mol.Å using the Tripos force field21. UCSF Chimaera 1.1222
(https://www.cgl.ucsf.edu/chimaera),
a
visualisation tool for
molecular modelling and structural biology, was used to remove
molecules, ions, and water and to minimise the structure of pro-
teins and ligands, using the Gasteiger charges with 1000 steps of
minimisation. Both ligands and receptor were then converted to
pdbqt format. AutoDock Vina23 (http://vina.scripps.edu), an open-
Cells were then incubated for 24 h in DMEM containing 0.2% FCS source programme for molecular docking, was used to investigate
and increasing concentrations of the compound tested or vehicle ligand-protein affinity.
A
grid box was centred (x ¼ 17.949,
(DMSO). At the end of the experiment, cells were washed once y ¼ 19.682, and z ¼ 15.341) on the active site of PPARc LBD, to
with ice-cold PBS and the luciferase and the b–galactosidase cover the pocket with the main residues of receptor binding site.
assays were performed as described previously20. Cells were incu- The best conformation was chosen with the lowest docked
bated 24 h in the presence of indicated concentrations of com- energy, based on complete docking search (ten runs). The interac-
pound. Luciferase activity was measured and normalised to tions of PPARc LBD with the ligands, hydrogen bonds, bond
internal control b-galactosidase activity. Compounds which elicited lengths, Root Mean Square Difference (RMSD) were analysed using
on average at least 80% activation of PPARa or PPARc versus Chimaera software. The docking solutions of tesaglitazar into

JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY
533
Scheme 1. Synthesis of 5-benzoyl-3,3-difluoro-1,3-dihydro-2H-indol-2-one 11. Reagents and conditions: (a) DAST, DCM, r.t.; (b) i: i-PrMgCl, n-BuLi, dry THF, 0 ꢁC; ii: ben-
zaldehyde, ꢂ78 ꢁC; (c) Dess-Martin periodinane, DCM, r.t.
Scheme 2. Synthesis of optically pure a–alkoxyphenylpropionic acids 21, 22. Reagents and conditions: (a) ethanol or trifluoroethanol [Rh(OAc)2]2,toluene, reflux; (b)
1,2-bromo-chloroethane, K2CO3, CH3CN, reflux; (c) NaH, dry THF, 0 ꢁC to r.t.; (d) H2, Pd/C, ethanol, r.t.; (e) LiOH, THF/H2O, r.t.; (f) 1-ethyl-3–(3-dimethylaminopropyl)-car-
bodiimide hydrochloride, triethylamine, HOBT, (S)-(-)-2-phenylglycinol, DCM, 0 ꢁC to r.t.; (g) 5 M H2SO4, dioxane/H2O, reflux.
binding site using AutoDock Vina converged consistently towards of potassium carbonate in DMF at 90 ꢁC, and the desired acids
31–38 were obtained after lithium hydroxide mediated saponifica-
tion (Scheme 3). Synthesis of enantiomerically pure 41a,b and
42a,b is outlined in Scheme 4. Condensation of 2 with the optic-
ally pure carboxylic acids 21a,b and 22a,b was performed under
mild conditions, employing NaH in HMPA at room temperature, in
order to prevent partial racemisation. Finally, racemic or optically
pure aryl ketones 32, 41 and 42 were further functionalised into
the corresponding oxime derivatives 39, 40 and 43–46 by treat-
ment with hydroxylamine hydrochloride or O-methylhydroxyl-
amine hydrochloride in pyridine. Surprisingly, while introduction
of oxime and oxime ethers provided exclusively the E isomers
(compounds 39a, 40a,b, 43a, 44a,b, 45a, 46a,b), assigned by
NOE experiments, condensation of hydroxylamine hydrochloride
with the trifluoroethyl derivative 32b led to the formation of a
racemic mixture of E and Z isomers 39b.
a unique binding mode within a 1.56 Å RMSD in comparison with
the co-crystallized tesaglitazar and showed binding energy of
ꢂ8.2 kcal/mol for protein–ligand complex.
3. Results and discussion
3.1. Chemistry
5-benzoyl-benzothiazol-2-one (1)24 and 6-benzoyl-benzothiazol-2-
one (2)25, 6-benzoyl-benzothiazin-3-one (3) and 7-benzoyl-benzo-
thiazin-3-one (4)26, 6-benzoyl-benzoxazin-3-one (5)27, and 7-ben-
zoyl-benzoxazin-3-one (6)28 and finally 5-benzoyl-1,3-dihydro-2H-
indol-2-one (7)29 were synthesised according to well-described
procedures. 5-Bromoisatin (8) was easily converted to 5-bromo-
3,3-difluoro-1,3-dihydro-2H-indol-2-one (9) using diethylaminosul-
fur trifluoride (DAST) in DCM30. Bromo derivative 9 was then sub-
jected to a halogen–magnesium exchange reaction with in-situ
produced isopropyl magnesium di-n-butyl lithium ate complex
(iPrMgnBu2Li) at ꢂ10 ꢁC. Benzaldehyde was then added at ꢂ78 ꢁC
to provide the corresponding benzyl alcohol 10 as a racemic mix-
ture31. Finally, 5-benzoyl-3,3-difluoro-1,3-dihydro-2H-indol-2-one
(11) was obtained by oxidation of alcohol 10 with Dess-Martin
periodinane in DCM (Scheme 1)32.
We previously described the synthesis of the key a-alkoxy pro-
pionic acid ester racemates 17a,b33 and the resolution of the
optically pure enantiomers 21a and 22a15. Herein, we also per-
formed synthesis of the optically pure trifluoroethoxy derivatives
21 b and 22 b by chromatographic separation of diastereoisomeric
amides 19 b and 20 b resulting of the reaction of the acid 18 b
with chiral (S)-2-phenylglycinol (Scheme 2). The condensation
reaction between benzoyl heterocycles and racemic a-ethoxy pro-
3.2. In vitro evaluation: binding studies and
transactivation assays
Compounds 31–38 were characterised by determining the bind-
ing affinity to human PPARc using a competitive binding assay
with [3H]rosiglitazone, the appropriate radioligand for PPARc. The
binding profiles of compounds were compared to the profiles of
several references: rosiglitazone, a full PPARc agonist and muragli-
tazar, a dual PPARa/c agonist which was discontinued in clinical
trials for greater incidence of oedema, heart failure, renal dysfunc-
tion and weight gain (Table 1). Except 6-benzoyl-benzothiazinone
derivative 33, all the tested compounds displayed potent binding
affinities to PPARc with Ki values lower than 10 nM. The results are
in agreement with the structural frameworks of compounds
31–38 and reference compounds which, like most PPAR activators,
pionic acid esters 17a,b was classically carried out in the presence are conformed to a three-module structure, with a binder acidic

534
A. HURTEVENT ET AL.
Scheme 3. Synthesis of PPAR agonists 31–38. Reagents and conditions: (a) K2CO3, DMF, 120ꢁC; (b) LiOH, THF/H2O, r.t.
Scheme 4. Synthesis of optically pure and oxime derived PPAR agonists 39–46. Reagents and conditions: (a) K2CO3, 17a or 17 b, DMF, 120 ꢁC; (b) LiOH, THF/H2O, r.t;
(c) hydroxylamine hydrochloride or O-methylhydroxylamine hydrochloride, pyridine, reflux; (d) NaH, 21a,b or 22a,b, HMPA, r.t.
group, an ethoxyphenyl linker and an effector end bearing a large at 10 mM on the PPARa receptor subtype equivalent to the refer-
hydrophobic tail part1. Molecular mechanisms will be addressed in ence WY14,643. Benzothiazin-3-one analogues displayed more
the molecular docking studies in order to understand the large contrasted results with functional activity ranging from 37 nM to
shift of binding affinity induced by the replacement of an oxygen 219 nM on PPARc and from 2 mM to 10 mM on PPARa. While 7-ben-
atom by a sulphur atom in the 6-benzoyl substituted benzazinone zoyl derivative 34 acted as dual full PPARa/c agonist, its 6-benzoyl
series of compounds while no loss of affinity occurred with the 7- counterpart 33 should be considered as partial PPARc agon since
benzoyl derivatives.
it displayed lower potency (ꢄ 70%) on PPARc and was found
Functional activity of compounds 31–38 was measured in a totally inactive (potency ꢄ 20%) against PPARa. Functional activity
transient transfection assay using human pGAL4hPPARa and results obtained for compound 33 were in accordance with the
human pGAL4hPPARc. The results are given in Table 1. All the tar- binding studies. The oxygen atom replacement by a sulphur atom
get compounds were tested as racemic mixtures and were func- in the 6-benzoyl substituted series of compounds did not seem to
tionally inactive at 10 mM against human PPARd. The functional be well tolerated for PPARa/c activity in comparison with the
profiles of test compounds were compared to the same references steric bulk of 7-benzoyl substituted derivatives. In order to assess
as for binding studies for PPARc and to WY14,643, a full fibrate the impact of oxygen or sulphur contained heterocycles on PPAR
PPARa agonist. Benzothiazol-2-one derivatives 31 and 32a were functional activity, 5-benzoyl-1,3-dihydro-2H-indol-2-one 37 and
considered as dual full PPARa/c agonists with potency ꢃ 80%. 5- its 3,3-difluoro derivative 38 were designed and synthesised.
Benzoyl derivative 31 exhibited better a functional activity than Replacement of a C–H bond with fluorine may lead to special
its 6-benzoyl counterpart 32a and proved to interact better with beneficial effects which are linked with its small size, its high elec-
the PPARa ligand binding domain (LBD) (compounds 31 and 32a tronegativity and low polarizability and its lipophilicity34. These
have respective PPARa EC50 of 256 and 2400 nM). In the benzoxa- structural modifications led to a slight decrease in c functional
zin-3-one series, 6- and 7-benzoyl substituted derivatives 35 and efficiency (ꢄ 75%) while maintaining good PPARc potency (EC50
ꢄ
36 were equipotent with a very potent full PPARc agonist 40 nM), suggesting that compounds 37 and 38 could be consid-
pharmacologic profile (potency > 100%) and a full agonist profile ered as partial PPARc agonists. However, direct comparison

JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY
535
Table 1. In vitro profile of compounds 31–38 on PPARc affinity and PPARa/c Table 2. In vitro profile of compounds 32, 39–46 on PPARc affinity and PPARa/
transactivation. c transactivation.
hPPAR gene reporter
Ki
aGal4 aEC50 cGal4 cEC50
hPPAR gene reporter
Cmpd
X
R
Stereo (nM)b
(%)c
(nM)d
(%)c
(nM)d
Ki
aGal4
aEC50
cGal4
cEC50
32a
39a
39b
40a
40b
41a
42a
43a
44a
44b
45a
46a
O
NOH
NOH
CH3 Rac
CH3 Rac
CF3 Rac
4
2
165
4
1.3
0.5
70
0.5
0.7
3
100
129
29
159
56
166
0
153
154
59
2400
10,000
10,000
129
180
522
10,000
10,000
32
89
91
44
87
95
142
39
123
115
150
66
15
24
10
2
7
8
300
16
2
0.9
799
558
9
Cmpd
X
n
Posa
(nM)b
(%)c
(nM)d
(%)c
(nM)d
31
32a
33
34
35
36
37
38
S
S
S
S
O
O
0
0
1
1
1
1
0
0
5
6
6
7
6
7
5
5
8
4
220
4
3
1
6.5
4
8
2
/
81
100
19
116
97
80
100
89
256
2400
10000
2050
10,000
10,000
10,000
10,000
10,000
595
145
89
69
61
15
219
37
2
80
40
5
NOCH3 CH3 Rac
NOCH3 CF3 Rac
O
O
NOH
NOCH3 CH3
NOCH3 CF3
NOH
NOCH3 CH3
NOCH3 CF3
97
CH3
CH3
CH3
S
R
S
S
S
R
R
R
119
113
60
CH2
CF2
75
525
rosie
muraf
WY14643
28
84
100
100
128
N.A.
4
3
N.A.
CH3
210
30
10,000
1480
1665
10,000
595
86
33
8
2
/
124
117
28
84
100
87
10,000
46b
116
100
128
N.A.
rosie
muraf
WY14643
4
3
N.A.
aPos: position of the benzoyl substitution on the heterocycle.
bhPPARc binding affinity: Ki values were calculated according to the equation Ki
¼ IC50/(1 þ [L]/Kd), where IC50 is the concentration of test compound required
to inhibit 50% of the specific binding of the radioligand, [L] is the concentra-
tion of the radioligand used, and Kd is the dissociation constant for the radioli-
gand at the PPARc receptor.
10,000
aPos: position of the benzoyl substitution on the heterocycle.
bKi values were calculated according to the equation Ki ¼ IC50/(1 þ [L]/Kd),
where IC50 is the concentration of test compound required to inhibit 50% of
the specific binding of the radioligand, [L] is the concentration of the radioli-
gand used, and Kd is the dissociation constant for the radioligand at the
PPARc receptor.
cEfficiency: Emax was the maximal PPAR fold activation relative to maximum
activation obtained with WY14643 (10 mM) and rosiglitazone (1 lM) corre-
sponded to 100% in GAL4 chimeric hPPARa and hPPARc system.
dEC50 Concentration required to induce 50% maximum activity of
:
cPotency: Emax was the maximal PPAR fold activation relative to maximum acti-
vation obtained with WY14643 (10 mM) and rosiglitazone (1 lM) corresponded
to 100% in GAL4 chimeric hPPARa and hPPARc system.
tested compound.
eRosiglitazone.
fMuraglitazar.
dEC50 Concentration required to induce 50% maximum activity of
:
NA: not active.
tested compound.
eRosiglitazone.
fMuraglitazar.
NA: not active.
between compounds 37, 38 and 32a revealed that replacement
of the sulphur atom by a methylene derivative weakens the
ligand–PPARa interaction and likely decreases activity. We decided
to select and develop for further studies, compound 32a bearing
a benzothiazol-2-one which seems to be the most tolerant of the
tested heterocycles and for which acylation in position 6 was
chemically easier than its 5-benzoyl counterpart.
Resolution of the racemate 32a into its optical antipodes first
led to compound 41a, which corresponded to the (S)-enantiomer
and possessed very potent binding affinity to PPARc with Ki value
lower than 1 nM and acted as full dual PPARa/c agonist (Table 2).
In contrast, its (R)-configured counterpart 42a proved to interact
more weakly with the PPARc LBD with Ki value of 70 nM and was
found to be a selective partial PPARc agonist with no activity for
the PPARa subtype. These data were in accordance with previous
studies describing PPAR agonists containing (S)-ethoxypropanoic
acid which displayed higher activities than the (R)-stereoisomer
analogues at both PPARa and PPARc receptor subtypes35.
ether led to compounds 40a,b exhibiting better a functional activ-
ity than the carbonyl counterpart 32a and especially the non-sub-
stituted oximes 39a,b. Introduction of trifluoroethoxy group led to
compound 39 b displaying a selective partial PPARc agonist profile
and to compound 40b acting as dual PPARa/c agonist with partial
PPARa and full PPARc agonist activities. These results confirm that
the incorporation of substituents such as methyl oxime ether and
trifluoroethoxy group strengthens the ligand–PPARa interaction
and likely increases activity while maintaining good PPARc
potency. We have next evaluated optically pure stereoisomers of
racemates 39a and 40a,b for both binding and transactivation
studies. As previously reported, (S)-configured derivatives 43a,
44a,b proved to interact better with the PPARc LBD with binding
affinities 10- to 400-fold more potent than their (R)-counterparts
45a, 46a,b. They are also highly potent agonists of both human
PPARa and c in cellular assays except for non-substituted oxime
derivatives 43a and 45a which can be considered as selective
PPARc agonists.
Functionalization of the ketone tail portion of the acyl group
with O-methyl oxime ether or introduction of a trifluoroethoxy
group in previous PPAR agonist series developed in our laboratory
were found to respectively enhance PPARa and decrease PPARc
functional activity15,33,36. These chemical modulations were then
applied by oxime forming reactions on the benzoyl part of ethoxy
In the (S)-series of stereoisomers, introduction of an O-methyl
oxime ether considerably improved PPARa efficiency and potency
while replacement of ethoxy group by its trifluoro analogue led to
compound 44 b with lower functional activity, characterised by a
32a or trifluoroethoxy 32 b racemates in order to assess the partial PPARa agonist profile. These chemical modulations didn’t
impact of the nature of the substituents on PPAR transactivation affect the PPARc receptor subtype leading to compounds with
(Table 2). As previously reported, incorporation of O-methyl oxime very potent PPARc agonist profile.

536
A. HURTEVENT ET AL.
Figure 2. Predicted binding mode of (A) (S)-34 (pink) and (S)-36 (cyan) and (C) (S)-33 (pink) and (S)-35 (cyan) enantiomers with PPARc LBD (PDB id 1I7I). Key amino
acid side chains are shown in white stick format and are labelled and hydrogen bonds are shown in red dotted lines. Overlapping and molecular surface maps of (B)
(S)-34 (pink) and (S)-36 (cyan) and (D) (S)-33 (pink) and (S)-35 (cyan) enantiomers with PPARc LBD (PDB id 1I7I). The protein and key amino acid side chains are
shown in white rounded ribbon and white stick format, respectively. The molecular surface maps are shown in grey.
3.3. Molecular docking studies
in terms of deformed torsional angles which are more pronounced
in the six-membered rings containing sulphur atoms relative to
those containing oxygen atoms.
Molecular modelling studies were conducted to understand the
large shift of binding affinity induced by the replacement of an
oxygen atom by a sulphur atom in the 6-benzoyl substituted ben-
zazinone series of compounds while no loss of affinity occurred
with the 7-benzoyl derivatives. Whereas compounds 33–36 were
synthesised and evaluated as racemic mixtures, only (S)-enantiom-
ers have been analysed in docking studies, since (S)-stereoisomers
displayed the best pharmacological profiles described in the litera-
ture. Crystal structure of PPARc (PDB id: 1I7I)37 co-crystallized with
tesaglitazar was downloaded from PDB database. The binding
poses of 7-benzoyl benzazinones 34 and 36 with the LBDs of
PPARc are shown in Figure 2(A). In addition to the classical hydro-
gen bondings with His323, His449 and Tyr473, it was apparent
that the benzoyl moiety and the benzoxazin-3-one or benzothia-
zin-3-one cores are buried in a binding cavity of PPARc LBD com-
posed of a cluster of hydrophobic residues (Leu255, Ile262, Ile281,
Val339, Ile341, Met348 and Leu353). In the 7-benzoyl series of
compounds, each sulphur 34 or oxygen 36 derivative is well
superimposed with each other in the PPARc LBD with the hetero-
cyclic cores deeply oriented in the hydrophobic pocket and the
benzoyl moieties directed towards the solvent (Figure 2(B)). In the
6-benzoyl series of compounds, benzoxazin-3-one 35 performed
the same type of interactions as its 7-benzoyl counterpart with
the heterocycle core in the hydrophobic cavity and the benzoyl
exposed to the solvent (Figure 2(C,D), cyan molecule). However,
the benzothiazin-3-one derivative 33 didn’t hinder at all the
hydrophobic pocket since the set of binding poses adjusts both
the phenyl part of benzoyl and the benzothiazinone sulphur atom
3.4. In vivo biological evaluation
The in vivo effect of test compounds was determined by measur-
ing glycaemia, triglyceridemia, insulinemia, and body weight using
ob/ob mice (Table 3). The ob/ob mice were obese, insulin resistant
with hypertriglyceridaemia and hyperglycaemia, and have been
used as a rodent model of obesity-induced insulin resistance. In
this model, mice were dosed orally with either synthesised com-
pounds or standard reference compounds (rosiglitazone and mur-
aglitazar) at 8.4 mMkgꢂ1 and 3 mgkgꢂ1 respectively for 4 days. As
a side effect index, body weight was also measured daily, and
body weight variation was calculated as a percentage of the dif-
ference in body weight between days 4 and 0. The results were
normalised to those obtained with rosiglitazone in the same
experiment, which was set to 100%. Benzoyl derivatives 32a, 41a
and 42a were not evaluated in vivo with regard to their low
absorption values with CaCO2 cells (< 25%), an in vitro model pre-
dicting membrane permeability38. In this model, oxime derivatives
displayed good percentages of absorption ranging from 65% to
100%, except compound 45a with only 31% in CaCo2 permeabil-
ity. Racemate 39a bearing an oxime function displayed in vivo
profile similar to reference compounds, but without promoting
body weight gain compared with rosiglitazone and muraglitazar.
Interestingly, incorporation of O-methyl oxime ether led to com-
pound 40a showing a slight improvement of the pharmacological
towards the solvent (Figure 2(C,D), pink molecule). The unex- activity in terms of reducing triglyceridemia, glycaemia and insuli-
pected PPARc binding affinity of compound 33 can be explained nemia. However, no improvement was obtained in terms of body

JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY
537
Table 3. In vivo efficacy of compounds 39a,b, 40a,b, 43a, 44a,b, 45a in ob/ob
trifluoroethoxy group followed by enantiomeric resolution led to
the (S)-stereoisomer 44 b. On the gene reporter assays, this com-
pound displayed a very potent full PPARc agonist pharmacologic
profile and a weak partial agonist profile on the PPARa receptor
subtype. This kind of pharmacological profile, common to numer-
ous PPARc ligands, suggested a potent insulin sensitivity and
robust glucose-lowering activity but certainly shadowed by the
risk for fluid retention and weight gain. However, after 4 days of
oral treatment with 44 b, ob/ob mice did not gain weight com-
pared with rosiglitazone as reference, while keeping high efficacy
on the decreasing blood parameters. Compound 44 b seems to
differentially induce specific PPAR receptor effects depending on
the cellular context with high anti-diabetic properties and low
potency in terms of effects on adipose generation, fluid retention
and weight-gain as characterised by SPPARMs. Complementary
studies will be performed to evaluate the effect of compound
44 b in term of osteoporosis and cardiac function to reinforce its
safety profile. In conclusion, 6-benzoyl-benzothiazol-2-one is a
scaffold that could be substituted to develop therapeutic agents
for diabetes and/or serve as a lead compound for further drug
design studies targeting PPAR-c and PPARa for effective manage-
ment of type 2 diabetes and dyslipidemia without inducing
weight gain.
mice animal models.
Change
Glyc
(%)a
Insd
Cmpd
TGb
DBWe
39a
39b
40a
40b
43a
44a
44b
45a
rosif
murag
ꢂ69
ꢂ30
ꢂ83
ꢂ54
ꢂ33
ꢂ79
ꢂ69
21
ꢂ49
ꢂ18
ꢂ58
ꢂ37
ꢂ55
ꢂ46
ꢂ36
ꢂ7
ꢂ34
ꢂ10
10
75
ꢂ76
ꢂ55
ꢂ29
ꢂ81
ꢂ89
51
188
ꢂ70
113
177
ꢂ17
328
100
206
ꢂ46
ꢂ57
ꢂ46
ꢂ73
ꢂ34
ꢂ46
aPercent change versus control for ob/ob mice at day 4.
bTriglycerides.
cGlycemia.
dInsulin.
eBody weight variation between day 0 and day 4 are expressed in% of rosiglita-
zone in the same study.
fRosiglitazone.
gMuraglitazar.
weight gain showing the same level as muraglitazar and suggest-
ing the same side effects. Introduction of a trifluoroethoxy group
led to less potent racemates 39 b and 40 b but with a sharp
decrease in body-weight gain compared with rosiglitazone. These
results are consistent with the results obtained in the PPARa and
c gene reporter assays. Indeed, incorporation of substituents such
as methyl oxime ether and trifluoroethoxy group are benefiting
for PPAR activity regulation and so for effective management of
dyslipidemia without inducing body weight gain. The same results
were observed with the (S)-derivative 44 b in which O-methyl
oxime ether allowed significant decreases in serum triglyceride,
glucose and insulin levels compared with its oxime counterpart
43a. The CF3 group incorporation, beyond keeping a good in vivo
efficacy, provided a robust reduction of body weight induced with
compound 44a, strengthening the beneficial pharmacological
effect of C-H bond replacement with fluorine. Compound 44 b
may be considered as a SPPARcM since this full PPARc agonist
retains the insulin-sensitizing and glucose-lowering actions while
mitigating or eliminating the undesirable side effects. Finally, only
the (R)-stereoisomer 45a was engaged in the in vivo experiments
and was found inactive as the whole of PPAR ligands described in
the literature1.
Acknowledgements
€
We are thankful to Gael Ostyn for proof-reading this paper.
Disclosure statement
No potential conflict of interest was reported by the authors.
References
1. Pirat C, Farce A, Lebegue N, et al. Targeting peroxisome pro-
liferator-activated receptors (PPARs): development of modu-
lators. J Med Chem 2012;55:4027–61.
2. Rogler G. Significance of anti-inflammatory effects of PPAR
agonists? Gut 2005;55:1067–9.
3. Tan CK, Zhuang Y, Wahli W. Synthetic and natural
Peroxisome Proliferator-Activated Receptor (PPAR) agonists
as candidates for the therapy of the metabolic syndrome.
Expert Opin Ther Targets 2017;21:333–48.
4. Conclusion
4. Ivanova EA, Parolari A, Myasoedova V, et al. Peroxisome pro-
liferator-activated receptor (PPAR) gamma in cardiovascular
disorders and cardiovascular surgery. J Cardiol 2015;66:
271–8.
5. Chung JH, Seo AY, Chung SW, et al. Molecular mechanism
of PPAR in the regulation of age-related inflammation.
Ageing Res Rev 2008;7:126–36.
6. Botta M, Audano M, Sahebkar A, et al. PPAR agonists and
metabolic syndrome: an established role? Int J Mol Sci 2018;
19:1197.
7. Hong F, Xu P, Zhai Y. The opportunities and challenges of
peroxisome proliferator-activated receptors ligands in clinical
drug discovery and development. Int J Mol Sci 2018;19:
2189.
Dual PPARa/c agonists that were developed to target hyperlipid-
aemia and hyperglycaemia in type 2 diabetes patients, caused car-
diac dysfunction or other adverse effects as fluid retention and
body-weight gain. Thus, there was significant interest in the
design of novel partial agonists and/or selective PPAR modulators
(SPPARMs) corresponding to a safer generation of PPAR ligands
that evoke fewer side effects while preserving insulin-sensitizing
potential. In this context we have reported the design of various
nitrogen heterocycles containing a-ethoxyphenylpropionic acid
chain 31–38 as PPAR agonists. Except 6-benzoyl-benzothiazinone
derivative 33, all the tested compounds displayed potent binding
affinities to PPARc with Ki values lower than 10 nM. Molecular
docking studies showed that the benzothiazin-3-one heterocycle
wasn’t able to correctly accommodate its 6-benzoyl substituent in
the hydrophobic pocket. 6-Benzoyl-benzothiazol-2-one which was
the most tolerant of the tested heterocycles was further investi-
gated to identify new PPAR ligands with the best in vitro pharma-
cological profiles. Incorporation of O-methyl oxime ether and
€
8. Yki-Jarvinen H. Thiazolidinediones. N Engl J Med 2004;351:
1106–18.
9. Lago RM, Singh PP, Nesto RW. Congestive heart failure and
cardiovascular death in patients with prediabetes and type

538
A. HURTEVENT ET AL.
2 diabetes given thiazolidinediones: a meta-analysis of rand-
Analogues by a Palladium Coupling Reaction. Synthesis
omised clinical trials. Lancet 2007;370:1129–36.
2011;24:480–4.
10. Bailey CJ. Learning from tesaglitazar. Diab Vasc Dis Res 25. Yous S, Poupaert JH, Lesieur I, et al. AlCl3-DMF reagent in
2007;4:161–2.
the Friedel-crafts reaction. Application to the acylation reac-
11. Zhang J, Liu X, Xie XB, et al. Multitargeted bioactive ligands
tion of 2(3H)-benzothiazolones. J Org Chem 1994;59:1574–6.
for PPARs discovered in the last decade. Chem Biol Drug 26. Carato P, Moussavi Z, Sabaouni A, et al. Synthesis of 6- and
Des 2016;88:635–63. 7-acyl-4H-benzothiazin-3-ones. Tetrahedron 2006;62:9054–8.
12. Motani A, Wang Z, Weiszmann J, et al. INT131: a selective 27. Hurtevent A, L’Helgoual’ch JM, Carato P, Lebegue N, Leclerc
modulator of PPARc. J Mol Biol 2009;386:1301–11.
13. Lee DH, Huang H, Choi K, et al. Selective PPARc modulator
V, Berthelot P, Dacquet C, Ktorza A, Caignard DH. Int Patent
PCT FR 06/000175; 2006.
INT131 normalizes insulin signaling defects and improves 28. Moussavi Z, Lesieur D, Lespagnol C, et al. 7-Acyl-2,3-dihydro-
bone mass in diet-induced obese mice. Am J Physiol
1,4-benzoxazin-3-ones and normolipemic properties. Eur J
Endocrinol Metab 2012;302:E552–60.
Med Chem 1989;24:54–60.
14. Zhang F, Lavan BE, Gregoire FM. Selective modulators of 29. Poupaert JH, Depreux P, McCurdy CR. Unsymmetrical diary-
PPAR-gamma activity: molecular aspects related to obesity
and side-effects. PPAR Res 2007;2007:32696.
lketones from electron-rich Heterocyclic arenes. Monatsh
Chem 2003;134:823–30.
15. Le Naour M, Leclerc V, Farce A, et al. Effect of oxime ether 30. Torres JC, Garden SJ, Pinto AC, et al. A synthesis of 3-fluo-
incorporation in acyl indole derivatives on PPAR subtype
selectivity. ChemMedChem 2012;7:2179–93.
16. Regitz M, Anschutz W, Liedhegener A. Reaktionen CH-aktiver
roindoles and 3,3-difluoroindolines by reduction of 3,3-
difluoro-2-oxindoles using a borane tetrahydrofuran com-
plex. Tetrahedron 1999;55:1881–92.
Verbindungen mit Aziden, XXIII Synthese von a-Diazo-phos- 31. Xu J, Jain N, Sui Z. Halogen–magnesium exchange of m-
€
phonsaureestern. Chem Ber 1968;101:3734–43.
and p-iodo or bromo-arenes bearing ortho-directing groups
17. Haigh D, Birrell HC, Cantello BCC, et al. Non-thiazolidine-
through ate complexes. Tetrahedron Lett 2004;45:6399–402.
dione antihyperglycaemic agents. Part 4: synthesis of ( )-, 32. Dess DB, Martin JC. A useful 12-I-5 triacetoxyperiodinane
(R)-(þ)- and (S)-(ꢂ)-enantiomers of 2-oxy-3-arylpropanoic
(the Dess-Martin periodinane) for the selective oxidation of
primary or secondary alcohols and a variety of related 12-I-5
species. J Am Chem Soc 1991;113:7277–87.
acids. Tetrahedron: Asymmetry 1999;10:1335–51.
18. Ferry G, Bruneau V, Beauverger P, et al. Binding of prosta-
glandins to human PPARc: tool assessment and new natural 33. Pirat C, Dacquet C, Leclerc V, et al. Anti-diabetic activity of
ligands. Eur J Pharmacol 2001;417:77–89.
fused PPARc-SIRT1 ligands with limited body-weight gain by
mimicking calorie restriction and decreasing SGK1 expres-
sion. Eur J Med Chem 2017;137:310–26.
19. Staels B, Koenig W, Habib A, et al. Activation of human aor-
tic smooth-muscle cells is inhibited by PPARa but not by
PPARc activators. Nature 1998;393:790–3.
34. Gillis EP, Eastman KJ, Hill MD, et al. Applications of fluorine
in medicinal chemistry. J Med Chem 2015;58:8315–59.
20. Kliewer SA, Umesono K, Noonan DJ, et al. Convergence of 9-
cis retinoic acid and peroxisome proliferator signalling path- 35. Kuhn B, Hilpert H, Benz J, et al. Structure-based design of
ways through heterodimer formation of their receptors.
Nature 1992;358:771–4.
indole propionic acids as novel PPARa/c co-agonists. Bioorg
Med Chem Lett 2006;16:4016–20.,
21. Clark M, Cramer IIR, van Opdenbosch N. Validation of the 36. Parmenon C, Guillard J, Caignard DH, et al. 4,4-Dimethyl-
general purpose tripos 5.2 force field. J Comput Chem 1989;
10:982–1012.
1,2,3,4-tetrahydroquinoline-based PPARa/c agonists. Part. II:
synthesis and pharmacological evaluation of oxime and
acidic head group structural variations. Bioorg Med Chem
Lett 2009;19:2683–7.
22. Pettersen EF, Goddard TD, Huang CC, Couch GS, et al. UCSF
Chimera? A visualization system for exploratory research
and analysis. J Comput Chem 2004;25:1605–12.
23. Trott O, Olson AJ. AutoDock Vina: improving the speed and
accuracy of docking with a new scoring function, efficient
optimization, and multithreading. J Comput Chem 2010;31:
455–61.
37. Cronet P, Petersen JF, Folmer R, et al. Structure of the
PPARa and -c ligand binding domain in complex with AZ
242; ligand selectivity and agonist activation in the PPAR
family. Structure 2001;9:699–701.
38. van Breemen RB, Li Y. Caco-2 cell permeability assays to
measure drug absorption. Exp Opin Drug Metab Toxicol
2005;1:175–85.
ꢀ
24. Pirat C, Ultre V, Lebegue N, et al. New Access to 5-
Substituted 1,3-Benzothiazol-2(3H)-ones and Their N-Methyl