Design and synthesis of new tetrahydroquinolines derivatives as CETP inhibitors

Article abstract of DOI:10.1016/j.bmcl.2012.04.042

This letter describes the discovery and SAR optimization of tetrazoyl tetrahydroquinoline derivatives as potent CETP inhibitors. Compound 6m exhibited robust HDL-c increase in hCETP/hApoA1 double transgenic model and favorable pharmacokinetic properties.

Full text of DOI:10.1016/j.bmcl.2012.04.042

Bioorganic & Medicinal Chemistry Letters 22 (2012) 3671–3675
Contents lists available at SciVerse ScienceDirect
Bioorganic & Medicinal Chemistry Letters
journal homepage: www.elsevier.com/locate/bmcl
Design and synthesis of new tetrahydroquinolines derivatives as CETP inhibitors
Ana Escribano a, , Ana I. Mateo a, Eva M. Martin de la Nava a, Daniel R. Mayhugh b, Sandra L. Cockerham b,
⇑
Thomas P. Beyer b, Robert J. Schmidt b, Guoqing Cao b, , Youyan Zhang b, Timothy M. Jones b,
Anthony G. Borel b, Stephanie A. Sweetana b, Ellen A. Cannady b, Nathan B. Mantlo b
a Centro de Investigación Lilly, Avda. de la Industria, 30, 28108 Alcobendas, Madrid, Spain
b ELi Lilly and Co. Lilly Research Laboratories, Indianapolis, IN 46285, USA
a r t i c l e i n f o
a b s t r a c t
Article history:
This letter describes the discovery and SAR optimization of tetrazoyl tetrahydroquinoline derivatives as
potent CETP inhibitors. Compound 6m exhibited robust HDL-c increase in hCETP/hApoA1 double trans-
genic model and favorable pharmacokinetic properties.
Received 30 January 2012
Revised 4 April 2012
Accepted 7 April 2012
Available online 13 April 2012
Ó 2012 Elsevier Ltd. All rights reserved.
Keywords:
CETP inhibitor
HDL-c
Tetrahydroquinolines
Plasma cholesteryl ester transfer protein (CETP) is a hydrophobic
glycoprotein that is secreted mainly from the liver and that circu-
lates in plasma, bound mainly to HDL.1 It facilitates the transfer
of cholesteryl esters from the atheroprotective high density lipo-
protein (HDL) to the proatherogenic low density lipoprotein choles-
terol (LDL) and very low density lipoprotein cholesterol (VLDL),
leading to lower levels of HDL but raising the levels of proathero-
genic LDL and VLDL. Epidemiologic data supports an inverse
relation between HDL-c and coronary heart disease.2 Therefore,
there has been a great interest in developing CETP inhibitors3 to in-
crease HDL-c plasma levels. Many studies in animals support the
hypothesis that inhibition of CETP activity is beneficial. For exam-
ple, the inhibition of CETP can reduce the progression of atheroscle-
rosis in rabbits.4 In humans, subjects with heterozygous CETP
deficiency and an HDL cholesterol level >60 mg/ml have a reduced
risk of coronary heart disease.5 Also clinical trials have confirmed
that pharmacological inhibition of CETP produces an increment of
serum HDL levels in humans.6 However, the efficacy of CETP inhib-
itors on reducing cardiovascular events remains uncertain. The
phase III trials in patients treated with torcetrapib (1) were discon-
tinued, following an excess of deaths and cardiac adverse effects.6a,7
Most likely, these undesirable effects arise from some compound-
specific and off-target effects, including increases in blood pressure,
sodium, bicarbonate and aldosterone levels, as well as a decrease in
potassium levels.8 These untoward effects have not been observed
with anacetrapib (2), dalcetrapib (3) or evacetrapib (4).9 (Fig. 1)
Our research program is based on identifying orally active CETP
inhibitors. Along with other groups,10 we focused our attention on
exploring the tetrahydroquinoline scaffold. This communication
describes structure–activity relationship studies of tetrazoyl deriv-
atives 6. Subsequent optimization was undertaken, leading to the
discovery of several analogues that significantly raised HDL-c in a
double transgenic mouse model expressing human CETP and apo-
lipoprotein AI (apo AI) assay.
We began by investigating the best replacement of the methylc-
arbamate at the nitrogen at C-4 in compound 1. As with our
previous approach toward the 1,5-tetrahydronaphthyridine ser-
ies,11 we explored different heterocycles. The synthesis of tetrazoyl
6, pyrazole 7 and isoxazole 8 derivatives is outlined in Scheme 1.
Commercially available 4-(trifluoromethyl)aniline was con-
verted to (+/ꢀ)-13 by reaction with the appropriate aldehyde fol-
lowed by treatment with vinyl acetamide in the presence of
p-toluenesulfonic acid. Subsequent reaction of (+/ꢀ)-13 with the
required chloroformate followed by acetamide hydrolysis, gave
rise to 4-amino derivatives (+/ꢀ)-14. The enantioselective synthe-
sis of (2R,4S)-14 was performed by coupling (R)-3-aminopentane-
nitrile with 1-chloro-4-(trifluoromethyl)benzene, nitrile followed
by hydrolysis, then treatment with benzyl chloroformate in the
presence of lithium tert-butoxide. Subsequent reduction of the
imide (2R,4S)-15 and final diastereoselective cyclization,12 pro-
vided the tetrahydroquinoline (2R,4S)-16. Acylation of the tetrahy-
droquinoline nitrogen with isopropyl chloroformate and benzyl
carbamate cleavage afforded (2R,4S)-14. Intermediates 14 were
⇑
Corresponding author. Tel.: +34 91 663 3410; fax: +34 91 663 3411.
E-mail address: escribano@lilly.com (A. Escribano).
Present address: Hengrui Pharmaceutical, 279 Wenjing Road, Shanghai 200245,
China.
0960-894X/$ - see front matter Ó 2012 Elsevier Ltd. All rights reserved.
http://dx.doi.org/10.1016/j.bmcl.2012.04.042

3672
A. Escribano et al. / Bioorg. Med. Chem. Lett. 22 (2012) 3671–3675
O
CF3
CF3
O
N
N
CF
O
3
CF3
O
CF3
N
O
O
O
CF3
F
Torcetrapib (1)
MK-0859
Anacetrapib (2)
N
CF3
N
R
N
CF3
N
N
O
4
CF3
CO2H
N
3
CF3
N
N
N
2
CF3
N1 R2
S
N
N
N
O
O
O
JTT-705
Dalcetrapib (3)
LY2484595
Evacetrapib (4)
(6)
Figure 1. CETP inhibitors.
O
O
O
O
HN
OBn
g
NH2
N
NH
CF
3
CF3
N
OBn
f
CF
CF3
3
h
CF3
CF3
c,d
a, b
N
R2
R2
H
R2
N
H
Cl
N
H
R2
NH2
O
O
(2R, 4S)-15
(2R, 4S)-16
(+/-)-13
(+/-)-14
or
(2R, 4S)-14
e
N
N
N
CF3
N
R
N
HN
N
HN
CF3
CF3
k
N
N
N
N
CF3
N
N
X
CF3
CF3
N
CF3
N
j
CF3
R2
l, m
CF3
CF3
R2
CF3
R2
CF3
R2
O
O
N
O
O
O
O
O
O
7 X= N
8 X= O
(+/-)-17
or
6 b-t
9, 10, 11 ,12
6 a
(2R, 4S)-17
Scheme 1. Reagents and conditions: (a) benzotriazole, R2CHO, toluene; (b) vinyl acetamide, pTsOHꢁH2O, toluene, RT ꢀ70 °C; (c) R1OCOCl, Py, 0 °C-rt; (d) 5 N HCl, 100 °C; (e)
(3,5-bis-CF3)PhCHO, NaBH(OAc)3, AcOH, DCE, rt; (f) (i) (R)-3-aminopentanenitrile methanesulfonic acid salt, CH2Cl2, CsCO3, 2-dicyclohexylphosphino-20-(N,N-dimethyl-
amino)biphenyl, phenylboronic acid, palladium acetate, toluene, 80 °C, (ii) conc H2SO4, toluene, 35 °C, (iii) benzyl chloroformate, 1 M lithium t-butoxide in THF, Et2O, ꢀ10–
0 °C; (g) sodium borohydride, EtOH, MgC12 , H2O; (h) (i) iPrOCOCl, Py, 0 °C-rt, (ii) H2, 10% Pd/C, 1 atm, EtOAc; (j) (i) CNBr, THF, iPr2NEt, rt, (ii) NaN3, Et3N, toluene, 110 °C; (k) R-
OH, PPh3, or X-R, K2CO3, DMF, acetone, rt or X-R , Et3N, acetonitrile, rt; (l) Diketene, THF, DMAP, rt; (m) X@N, NH2NH2, EtOH, P2O5, 90 °C or X@O, NH2OH, NaOAc, MeOH.
derivatized to the N-benzyl amino derivatives 17 by reductive ami-
nation with bis(trifluoromethyl)benzaldehyde. Reaction of (2R,4S)-
17 with diketene and subsequent cyclization with hydrazine or
hydroxylamine gave pyrazole 7 and isoxazole 8, respectively.
Treatment of 17 with cyanogen bromide in the presence of potas-
sium tert-butoxide, followed by condensation with sodium azide in
basic media produced the tetrazole 6a. Deprotonation of 6a with
potassium carbonate followed by reaction with the corresponding
alkyl halide, allowed the preparation of the alkyltetrazoles 6h–k
and 6o–q. Alternatively, treatment of 6a with the appropriate alco-
hol under Mitsunobu conditions gave rise to the tetrahydroquino-
lines 6b–g, 6l–m, 6r–t, 9, 10, 11 and 12.
continue the optimization with the iso-propyl carbamate at that po-
sition. Improvement of the CETP inhibition was achieved by replac-
ing the acetyl (5a–b) or carbamate (1) moieties on the nitrogen at C-
4 with 2-methyltetrazole (6b), while the unsubstituted tetrazole
was detrimental for activity (6a). Other five membered heterocy-
cles such as 3-methyl pyrazole (7) or 3-methylisoxazole (8) were
also tolerated.
Since the 2-methyl tetrazole markedly increased the potency,
we decided to explore the nature of the substitution at the
tetrazole moiety (Table 2). We first found that longer and branched
alkyl chains (6c–h) led to less potent compounds. Then, in order to
reduce the lipophilicity and improve solubility of the scaffold, we
introduced different polar groups onto the alkyl chain substitution
on the tetrazole ring. We observed that cyano (6i, 6j), hydroxy (6l,
6r) or amino (6m, 6s) groups were well tolerated, independent of
the chain length. Introduction of a carboxylic acid (6n) onto the
We next studied the replacement of the carbamate moiety at the
exocyclic nitrogen of the tetrahydroquinoline core (Table 1). We
first observed that the iso-propyl carbamate at N-1 improved the
potency of the acetyl derivatives (5a vs 5b). We decided then to

A. Escribano et al. / Bioorg. Med. Chem. Lett. 22 (2012) 3671–3675
3673
Table 1
Table 3
SAR study at exocyclic nitrogen
Influence of substitution at C-2 in combination with tetrazole substitution
CF3
N
N
CF3
R
O
N
R
N
N
N
N
N
4
3
CF3
CF3
CF3
2
CF3
R2
1
O
R1
O
O
a
Compound
R
R1
Et
CETP IC50 (nM)
Compoundb
R
R2
Me
Propyl
iso-Propyl
CETP IC50 (nM)
a
O
9b
10b
11b
Me
Me
Me
48
55
47
1
39
195b
57b
O
O
O
5a
5b
Et
12b
9r
Me
42
36
37
Me
iPr
OH
11r
iso-Propyl
N
OH
N
6a
6b
iPr
iPr
2310
13
NH2
9m
Me
47
40
N
N
N
NH2
NH2
11m
iso-Propyl
N
N
N
12m
54
a
7
8
iPr
iPr
26
24
Human CETP plasma IC50
All racemic.
.
N
N
b
O
N
a
Human plasma CETP13 IC50
Racemic.
.
b
propyl (10b), iso-propyl (11b, 11r, 11m) and cyclopropyl (12b,
12m) substituents are well tolerated, with the appropriate substi-
tution on the tetrazole ring.
alkyl chain was detrimental for activity, however potency was
recovered with the corresponding methyl ester (6o) and the pri-
mary amide (6p). Dimethyl substituted amide (6q) or amine (6t)
reduced potency when compared with the unsubstituted ana-
logues. We also attempted to determine the effect of substitution
at position C-2 of the tetrahydroquinoline core. The results are
summarized in Table 3, and showed that methyl (9b, 9r, 9m),
Finally we investigated alkylamino moieties as tetrazole ring
substituents (Table 4). Constrained analogues such as piperidine
9w were tolerated, but azetidine 9y had reduced potency. Amine
substitution also, gave a decrease in activity (9u, 9v, 9x).
Based on these in vitro SAR studies, we selected compounds 6j,
6l, 6m and 6r to test in our double transgenic mouse assay. Thus
the animals were given a 30 mpk oral dose and blood was taken
Table 2
SAR study at tetrazole substitution
N
N
CF3
N
R
N
N
N
CF3
CF3
O
O
6a-t
a
a
a
Compound
R
CETP IC50 (nM)
Compound
R
CETP IC50 (nM)
Compound
R
CETP IC50 (nM)
6b
6c
Me
13
74
6i
6j
23
15
6o
6p
44
49
COOMe
CONH2
CN
CN
Propyl
Cl
N
6d
Butyl
187
6k
58
6q
2350
O
OH
6e
6f
iso-Propyl
tert-Butyl
56
6l
16
29
6r
15
56
OH
NH2
>50000
6mb
6sb
NH2
N
6g
6h
iso-Butyl
20000
61
6nc
3790
6t
162
COOH
a
b
c
Human plasma CETP activity.
Obtained from the corresponding isoindoline 1,3-dione by treatment with hydrazine.
Obtained from the corresponding ester 6o via saponification.

3674
A. Escribano et al. / Bioorg. Med. Chem. Lett. 22 (2012) 3671–3675
Table 4
dual heterozygous mouse model, with favorable pharmacokinetic
profiles.
SAR on the alkylamino substituent
N
N
CF3
N
R
N
N
N
Acknowledgment
CF3
CF3
The authors gratefully acknowledge the Analytical Technologies
group, at Lilly for the analytical work.
O
O
Supplementary data
a
Compoundb
R
CETP IC50 (nM)
NH2
9m
9u
47
Supplementary data associated with this article can be found, in
the online version, at http://dx.doi.org/10.1016/j.bmcl.2012.04.042.
151
N
9v
218
78
N
References and notes
N
9w
1. (a) Tall, A. R. J. Lipid Res. 1993, 34, 1255; (b) McCarthy, P. A. Med. Res. Rev. 1993,
13, 139.
2. (a) Chapman, M. J.; Assmann, G.; Fruchart, J.-C.; Shepherd, J.; Sirtori, C.
European Consensus Panel Curr. Med. Res. Opin. 2004, 20, 1253. And references
cited therein; (b) Assmann, G.; Shulte, H.; Von Eckardstein, A.; Huang, Y.
Atherosclerosis 1996, 124, S11; (c) Linsel-Nitschke, P.; Tall, A. R. Nat. Rev. Drug
Discov. 2005, 4, 193 [Erratum: Nat. Rev. Drug Disc., 2005, 4, 698].
N
9x
9y
10100
327
N
a
3. (a) Kallashi, F.; Dooseop, K.; Kowalchick, J.; Park, Y. J.; Hunt, J. A.; Ali, A.; Smith,
C. J.; Hammond, M. L.; Pivnichny, J. V.; Tong, X.; Xu, S. S.; Anderson, M. S.; Chen,
Y.; Eveland, S. S.; Guo, Q.; Hyland, S. A.; Milot, D. P.; Cumiskey, A.-M.; Latham,
M.; Peterson, L. B.; Rosa, R.; Sparrow, C. P.; Wright, S. D.; Sinclair, P. J. Bioorg.
Med. Chem. Lett. 2011, 21, 558; (b) Vakalopoulos, A.; Schmeck, C.; Thutewohl,
M.; Li, V.; Bischoff, H.; Lustig, K.; Weber, O.; Paulsen, H.; Elias, H. Bioorg. Med.
Chem. Lett. 2011, 21, 488; (c) Lu, Z.; Napolitano, J. B.; Theberge, A.; Ali, A.;
Hammond, M. L.; Tan, E.; Tong, X.; Xu, S. S.; Latham, M. J.; Peterson, L. B.;
Anderson, M. S.; Eveland, S. S.; Guo, Q.; Hyland, S. A.; Milot, D. P.; Chen, Y.;
Sparrow, C. P.; Wright, S. M.; Sinclair, P. J. Bioorg. Med. Chem. Lett. 2010, 20,
7469; (d) Hunt, J. A.; Gonzalez, S.; Kallashi, F.; Hammond, M. L.; Pivnichny, J. V.;
Tong, X.; Xu, S. S.; Guo, Q.; Hyland, S. A.; Milot, D. P.; Sparrow, C. P.; Wright, S.
D.; Sinclair, P. J. Bioorg. Med. Chem. Lett. 2010, 20, 1019; (e) Rano, T.; Sieber-
McMaster, E.; Pelton, P. D.; Yang, M.; Demarest, K. T.; Kuo, G.-H. Bioorg. Med.
Chem. Lett. 2009, 19, 2456; (f) Kuo, G.-H.; Rano, T.; Pelton, P.; Demarest, K. T.;
Gibbs, A. C.; Murray, W. V.; Damiano, B. P.; Connelly, M. A. J. Med. Chem. 2009,
52, 1768; (g) Hunt, J. A.; Lu, Z. Curr. Top. Med. Chem. 2009, 9, 419. and references
therein; (h) Harikrishnan, L. S.; Kamau, M. G.; Herpin, T. F.; Morton, G. C.; Liu,
Y.; Cooper, C. B.; Salvati, M. E.; Qiao, J. X.; Wang, T. C.; Adan, L. P.; Taylor, D. S.;
Chen, A. Y. A.; Yin, X.; Seethala, R.; Peterson, T. L.; Nirschl, D. S.; Miller, A. V.;
Weigelt, C. A.; Appiah, K. K.; O’Connell, J. C.; Lawrence, R. M. Bioorg. Med. Chem.
Lett. 2008, 18, 2640; (i) Eary, C. T.; Jones, Z. S.; Groneberg, R. D.; Burgess, L. E.;
Mareska, D. A.; Drew, M. D.; Blake, J. F.; Laird, E. R.; Balachari, D.; O’Sullivan, M.;
Allen, A.; Marsh, V. Bioorg. Med. Chem. Lett. 2007, 17, 2608; (j) Shinkai, H. Expert
Opin. Ther. Patents 2009, 19, 1229. And references cited therein.
Human CETP plasma IC50
All racemic.
.
b
Table 5
Evaluation at 30 mg/Kg oral dose in hCETP/hAPO-A1 tg micea
Compound
%CETP inhibitionb
8 h
%HDL-c increasec
4 h
24 h
8 h
24 h
6j
6l
6m
6r
102
101
100
107
105
108
107
110
80
92
80
87
226
153
194
150
97
224
109
171
a
Formulation: corn oil (79.5%), oleic acid (20%), labrafil (0.5%) Species: male CETP
and ApoA1 heterozygote mice used for this experiment. Mice were orally dosed
with reference CETP compound and blood was taken from the mice at different time
point. Serum was aspirated off and tested for CETP activity.
b
Ex vivo CETP inhibition.
In vivo serum HDLc.
c
4. Barter, P. J.; Brewer, H. B., Jr.; Chapman, M. J.; Hennekens, C. H.; Tall, A. R.
Arterioscler. Thromb. Vasc. Biol. 2003, 23, 160.
5. Zhong, S.; Sharp, D. S.; Grove, J. S.; Bruce, C.; Yano, K.; Curb, J. D.; Tall, A. R. J.
Clin. Invest. 1996, 97, 2917.
Table 6
Pharmacokinetic profile of 6m
6. (a) Barter, P. J.; Caulfield, M.; Eriksson, M.; Grundy, S. M.; Kastelein, J. J. P.;
Komajda, M.; Lopez-Sendon, J.; Mosca, L.; Tardif, J.-C.; Waters, D. D.; Shear, C.
L.; Revkin, J. H.; Buhr, K. A.; Fisher, M. R.; Tall, A. R.; Brewer, B. N. Engl. J. Med.
2007, 357, 2109; (b) Bloomfield, D.; Carlson, G. L.; Sapre, A.; Tribble, D.;
McKenney, J. M.; Littejohn, T. W., III; Sisk, C. M.; Mitchel, Y.; Pasternak, R. C. Am.
Heart J. 2009, 157, 352; (c) De Grooth, G. J.; Kuivenhoven, J. A.; Stalenhoef, A. F.
H.; De Graaf, J.; Zwinderman, A. H.; Posma, J. L.; VanTol, A.; Kastelein, J. J. P.
Circulation 2002, 105, 2159.
Compound
Species
CL (mL/min/Kg)
Vdss (L/Kg)
t1/2 (h)
%F
6m
6m
Rat
Dog
8
2.5
3
2.5
6.1
6
7
15
Formulation: intravenous formulation: 20% solutol microemulsion/80% deionized
H2O.
Oral formulation: corn oil/oleic acid/labrafil 79.5:20:0.5.
Species: male sprague dawley cannulated rats.
Female beagle dogs dose: 1 mg/kg and 3 mg/kg.
Time course 0–72 h.
7. Nissen, S. E.; Tardif, J.-C.; Nicholls, S. J.; Revkin, J. H.; Shear, C. L.; Duggan, W. T.;
Ruzyllo, W.; Bachinsky, W. B.; Lasala, G. P.; Tuzcu, E. M. N. Engl. J. Med. 2007,
356, 1304.
8. De Haam, W.; Vries-van, De; Der Weij, J.; Van der Hoorn, J. W. A.; Gautier, T.;
Van der Hoogt, C. C.; Westerterp, M.; Romijn, J. A.; Jukema, J. W.; Havekes, L.
M.; Princenm, H. M. G.; Rensen, P. C. N. Circulation 2008, 117, 2515.
9. (a) Vergeer, M.; Stroes, E. S. Am. J. Cardiol. 2009, 104, 32E; (b) Cannon, C. P.;
Dansky, H. M.; Davidson, M.; Gotto, A. M., Jr; Brinton, E. A.; Gould, A. L.;
Stepanavage, M.; Liu, S. X.; Shah, S.; Rubino, J.; Gibbons, P.; Hermanowoski-
Vosatka, A.; Binkowitz, B.; Mitchel, Y.; Barter, P. Am. Heart J. 2009, 158, 513; (c)
Stein, E. A.; Stroes, E. S. G.; Steiner, G.; Buckley, B. M.; Capponi, A. M.; Burgess,
T.; Niesor, E. J.; Kallend, D.; Kastelein, J. J. P. Am. J. Cardiol. 2009, 104, 82; d Cao,
G.; Beyer, T. P.; Zhang, Y.; Schmidt, R. J.; Chen, Y. Q.; Cockerham, S. L.;
Zimmerman, K. M.; Karathanasis, S. K.; Cannady, E. A.; Fields, T.; Mantlo, N. B. J.
Lipids Res., in press.
10. a Deninno, M. P.; Magnus-Aryitey, G. T.; Ruggeri, R. B.; Wester, R. T. Patent
WO2000017164, 2000.; b Deninno, M. P.; Mularski, C. J.; Ruggeri, R. B.; Wester,
R. T. Patent WO2000017166, 2000.; c Allen, D. J. M.; Appleton, T. A.; Brostrom,
L. R.; Tickner, D. L. Patent WO2001040190, 2001.; d Kubota, H.; Sugahara, M.;
Furukawa, M.; Takano, M.; Motomura, D. Patent WO2005095409, 2005.; e
Groneberg, R. D.; Eary, C. T. Patent US20060270675, 2006.; f Ruggeri, R. B.;
at different time points as shown in Table 5. All compounds
showed demonstrated ex vivo CETP inhibition and a robust HDL-
c elevation at 8 and 24 h.
Compound 6m was selected for rat and dog pharmacokinetic
studies (Table 6), due to its relatively higher in vitro kinetic solubil-
ity among the analogues tested in simulated intestinal fluid (data
available in Supplementary data). 6m exhibited an acceptable
pharmacokinetic profile in dogs and rats, with a t1/2 of 6 h, rela-
tively low clearance and Vdss and moderate bioavailability.
In summary we have identified a series of substituted tetrazoyl
tetrahydroquinolines as potent CETP inhibitors that have demon-
strated the ability to significantly raise HDL-c in the hCETP/hApoA1

A. Escribano et al. / Bioorg. Med. Chem. Lett. 22 (2012) 3671–3675
3675
Magnus-Aryitey, G.; Shanker, R. M.; Lorenz, D. A.; Garr, C. D. Patent
US2006063803.
11. Fernandez, M.-C.; Escribano, A.; Mateo, A. I.; Parthasarathy, S.; Martin de la
Nava, E. M.; Wang, X.; Cockerham, S. L.; Beyer, P. B.; Schmidt, R. J.; Cao, G.;
Zhang, Y.; Jones, T. M.; Borel, A.; Sweetana, S. A.; Cannady, E. A.; Stephenson, G.;
Frank, S.; Mantlo, N. B. Submitted.
13. Plasma CETP assay: a donor particle containing a fluorescent cholesterol ester
analog was prepared similarly to what was described by Bisgaier et al. (Bisgaier
et al. J. Lipid Res., 1993, 34, 1625). The donor particle (3%) was incubated with
human plasma (96%) and test compound in DMSO (1%), VLDL as an acceptor
particle. CETP inhibitory activity was recorded as reductions in fluorescent
intensity with increasing compound concentrations. IC50 values were
determined by non-linear regression.
12. Damon, D. B.; Dugger, R. W.; Scott, R. W. WO02/088069, 2002.