Discovery of dimethyl pent-4-ynoic acid derivatives, as potent and orally bioavailable DGAT1 inhibitors that suppress body weight in diet-induced mouse obesity model

Article abstract of DOI:10.1016/j.bmcl.2018.04.051

Diacylglycerol acyltransferase (DGAT) is expressed abundantly in intestine, liver, and adipose tissues. DGAT1 is the crucial and rate-limiting enzyme that mediates the final step in triacylglycerol (TAG) resynthesis during dietary fat absorption. However, too much triacylglycerol (TAG) reserve will lead to genetic obesity (Hubert et al., 2000). DGAT1 knockout mice could survive and displayed a reduction in the postprandial rise of plasma TG, and increased sensitivity of insulin and leptin. Here we report the discovery and characterization of a novel selective DGAT1 inhibitor 29 to potentially treat obesity. Compound 29 showed lipid lowering effect in mouse lipid tolerance test (LTT) and also reduced body weight in DIO mice without observable liver damage.

Full text of DOI:10.1016/j.bmcl.2018.04.051

Accepted Manuscript
Discovery of dimethyl pent-4-ynoic acid derivatives, as potent and orally bio-
available DGAT1 inhibitors that suppress body weight in diet-induced mouse
obesity model
Tao Yu, Chengde Wu, NengYang Shih, Qi Li, Chichung Chan, He Pan, Dan
Yao, Yan Pan, Wei Liang, Liang Shen, Hui Zhao, Jian Li, Shuhui Chen
PII:
S0960-894X(18)30363-9
https://doi.org/10.1016/j.bmcl.2018.04.051
BMCL 25798
DOI:
Reference:
Bioorganic & Medicinal Chemistry Letters
To appear in:
Received Date:
Revised Date:
Accepted Date:
27 December 2017
16 April 2018
19 April 2018
Please cite this article as: Yu, T., Wu, C., Shih, N., Li, Q., Chan, C., Pan, H., Yao, D., Pan, Y., Liang, W., Shen, L.,
Zhao, H., Li, J., Chen, S., Discovery of dimethyl pent-4-ynoic acid derivatives, as potent and orally bioavailable
DGAT1 inhibitors that suppress body weight in diet-induced mouse obesity model, Bioorganic & Medicinal
Chemistry Letters (2018), doi: https://doi.org/10.1016/j.bmcl.2018.04.051
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Bioorganic & Medicinal Chemistry Letters
Discovery of dimethyl pent-4-ynoic acid derivatives, as potent and orally
bioavailable DGAT1 inhibitors that suppress body weight in diet-induced mouse
obesity model
Tao Yu*, Chengde Wu, NengYang Shih, Qi Li, Chichung Chan, He Pan, Dan Yao, Yan Pan, Wei
Liang, Liang Shen, Hui Zhao, Jian Li, Shuhui Chen
WuXi AppTec (Shanghai) Co., Ltd., 288 FuTe Zhong Road, Shanghai 200131, People’s Republic of China
ARTICLE INFO
ABSTRACT
Article history:
Received
Revised
Accepted
Available online
Diacylglycerol acyltransferase (DGAT) is expressed abundantly in intestine, liver, and
adipose tissues. DGAT1 is the crucial and rate-limiting enzyme that mediates the final step in
triacylglycerol (TAG) resynthesis during dietary fat absorption. However, too much
triacylglycerol (TAG) reserve will lead to genetic obesity.1 DGAT1 knockout mice could
survive and displayed a reduction in the postprandial rise of plasma TG, and increased
sensitivity of insulin and leptin. Here we report the discovery and characterization of a novel
selective DGAT1 inhibitor 29 to potentially treat obesity. Compound 29 showed lipid
lowering effect in mouse lipid tolerance test (LTT) and also reduced body weight in DIO
mice without observable liver damage.
Keywords:
DGAT1
Obesity
LTT
2009 Elsevier Ltd. All rights reserved.
DIO
Diacylglycerol acyltransferase (DGAT) is a microsomal
enzyme that plays a central role in the metabolism of cellular
glycerolipids. DGAT catalyzes the final step in triacylglycerol
(TAG) biosynthesis by converting diacylgycerol and fatty
treatment of FCS, HCV, NAFLD.3-5 Other compounds in
clinical or discovery stage include 2 (PF-04620110),5
3
(AZD-7687),7 4 (A-922500),8 compound 59 and compound
610 as shown in Figure 1.
acyl-coenzyme
A into triacylglycerol. DGAT plays a
fundamental role in the metabolism of cellular diacylglycerol
and is important in higher eukaryotes for physiologic
processes involving triacylglycerol metabolism such as
intestinal absorption, lipoprotein assembly, adipose tissue
formation, and lactation. Triacylglycerol (TAG) is the
essential material for mammal to maintain normal
physiological function. However, too much triacylglycerol
(TAG) reserve will lead to genetic obesity.1 While DGAT-2 is
essential for survival in mice2, Dgat-1-/- mice had normal basal
levels of plasma glucose and insulin. When subjected to a
glucose load, Dgat-1-/- mice tended to have lower glucose and
insulin levels than wild-type mice, suggesting improved
glucose metabolism in DGAT deficiency. Consequently,
DGAT-1 represents an attractive target for the treatment of
obesity.
In the past decade, Several research groups have
disclosed potent and selective DGAT1 inhibitors from several
distinct chemical series, including the most advanced
compound 1 (LCQ-908) which is in phase 3 clinical study for
Figure 1. Selected examples of DGAT1 inhibitors from literature
Based on the extensive work on DGAT1 inhibitors of
many
pharmaceutical
companies,
a
well-defined
pharmacophore has emerged for high activity. Most reported
E-mail address: yu_tao_001391@wuxiapptec.com.

of Et3N conditions afforded 23 analogs. The desired
compounds 25-41 were obtained from 23 analogs by
amination and subsequent hydrolysis.
DGAT1 inhibitors contain an H-bond donor/acceptor pair in
or with aromatic system, a central phenyl ring, a linker, and a
right hand side carboxylic acid. The spacer is typically
aromatic or aliphatic ring system which ensures right distance
and optimal orientation. 11,12
We sought to explore the possibility of employing
substituted acetylene novel space. The structure of alkyne is
more rigid and straight, along with the adjacent quaternary
carbon will be likely to help maintain the spatial distance and
optimal orientation between the two pharmacophores.
Furthermore, replacing cyclohexane or phenyl ring with
alkyne can decrease MW and LogP value. Alkyne group was
used in many drugs such as Ponatinib (cancer), Apatinib
(cancer), erlotinib (cancer), pralatrexate (cancer), Efavirenz
(HIV), rasagiline (Parkinsons disease), bosentan (PAH),
Regadenoson (Coronary artery disease), linagliptin (diabetes).
Herein we describe the identification of a promising candidate
5-(4-(4-amino-5-oxo-7,8-dihydropyrimido[5,4f][1,4]oxazepin
-6(5H)-yl)-2,6-dimethylphenyl)-3,3-dimethylpent-4-ynoic
acid (29), an effective compound in LTT (Lipid tolerance
test)13 and DIO (diet induced obesity)10 model. Meanwhile,
the extensive structure-activity relationship (SAR) of this
series was revealed here.
Target compounds 7a-7k were synthesized as shown in
Scheme 1. Commercially available 1-bromo-4-nitrobenzene 8,
4-iodobenzoic acid 10 or benzene halide 12, 14, 16 were used
as starting materials for desired compounds. The key
intermediates 9, 11, 13 were synthesized from starting
materials 8, 10, 12 by Sonogashira coupling reaction with
alkyne which were prepared by the reported procedure by
literature.14 The intermediate 9 was hydrogenation followed
by reacted with corresponding isocyanate or Boc2O to
afforded compound 7a, 7b, 7c (route A). Condensation
reaction carried out from intermediate 11 to afford compound
7d (route B). The intermediate 13 was reacted with
bis(pinacolato)diboron and then treated with different
bromide by Suzuki coupling reaction to obtain compound 7e,
7f, 7g (route C). Compound 7h, 7j were prepared by route D.
4-iodobenzoyl chloride as starting material was reacted with
isopropylmagnesium chloride in the presence of Fe(acac)3 to
afford 1-(4-iodophenyl)-2-methylpropan-1-one, which was
treated with Br2 followed by cyclization to afford the
intermediate 15. Compound 7h was obtained from
intermediate 15 by Sonogashira coupling reaction and
subsequent hydrolysis. Compound 7j was obtained from
compound 7h with NaBH4 treatment. Compound 7k was
synthesized in similar manner according to published
procedures.11 The synthetic route is described in route E of
Scheme 1.
Scheme 1. Reagents and conditions: (a) (i) diethyl 2-(2-methylbut-3-yn-
2-yl)malonate, CuI, Pd(PPh3)Cl2, TEA, DCM, reflux, 18 h, 31%; (ii)
NaOH, MeOH/H2O, 60 oC, 18 h, 88 %; (iii) 180 oC, H2O, sealtube,59%;
(b) (i) NiCl2.6H2O, NaBH4,MeOH, rt, 2 h, 91%; (ii) corresponding
isocyanate CHCl3, 1 h or Boc2O, TEA, MeOH, 2.5%-21%; (c) (i) ethyl
3,3-dimethylpent-4-ynoate, CuI, PPh3, Pd(PPh3)Cl2, DIEA,THF, reflux,18
h, 33%; (d) (i)pyridin-2-amine, HATU, DIEA, DCM, rt, 18 h,25%; (ii)
LiOH, MeOH, H2O, rt, 2 h, 21%; (e) ethyl 3,3-dimethylpent-4-ynoate,
CuI, PPh3, Pd(PPh3)Cl2, DIEA, DMF, 80 oC, 18 h, 70%; (f) (i)
bis(pinacolato)diboron, Pd(dppf)2Cl2, KOAc, dioxane, 80 oC, 18 h, 79%,
(ii) RBr, Pd(dppf)Cl2, K2CO3, dioxane/H2O, 100 oC, 12 h, (iii) LiOH.H2O,
THF/H2O, rt, 10 h; (g) (i) Isopropylmagnesium chloride, Fe(acac)3, THF,
rt, (ii) Br2/CHCl3, rt, 2 h, (iii) 5,6-diaminopyrimidin-4-ol, 1N HCl,
ethanol/H2O, reflux, 12 h; (h) (i) ethyl 3,3-dimethylpent-4-ynoate, CuI,
PPh3, Pd(PPh3)Cl2, DIEA, DMF, 80 oC, 18 h, (ii) LiOH.H2O, THF/H2O,
rt, 10 h; (j) NaBH4 MeOH; (k) (i) AD-mix-α, acetone/H2O, rt, 3 h, 74%
(ii) TBSCl, imidazole, DCM, 0 oC, 2 h, 79%; (iii) 2-Diazo-malonic acid
dimethyl ester, Rh2(OAc)4, toluene, 80 oC, 4 h, 66%; (iv) ethyl 3,3-
dimethylpent-4-ynoate, CuI, PPh3, Pd(PPh3)Cl2, DIEA, DMF, 80 oC, 5 h,
52%; (l) (i) Formimidoylamino-acetic acid , MeONa, MeOH, rt, 2 h,
95%; (ii) POCl3, toluene, reflux, 18 h, 18%; (iii) BocNH2, Pd2(dba)3,
xantphos, Cs2CO3, DMF, 90 oC, 18 h, 26%; (iv) TFA, rt, 3 h, 90%; (v)
LiOH.H2O, dioxane/H2O, rt, 18 h;
Compound 7m, 25-41 ware synthesized according to
published procedures15 or in a similar manner as shown in
Scheme 2. The synthesis of these compounds were initiated
from commercially available substituted benzene halide,
which reacted with ethyl 3,3-dimethylpent-4-ynoate14 in
presence of Pd(dppf)Cl2/CuI at reflux and further reacted with
2-((tert-butyldimethylsilyl)oxy)ethanamine in presence of x-
phos/Pd2(dba)3 utilizing Buchwald conditions. 21 analogs
were obtained form 20 analogs with 4,6-dichloropyrimidine-
5-carbonyl chloride by acylation reactions. Further, de-
protection using HCl/ethanol and cyclization in the presence
Scheme 2. Reagents and conditions: (a) ethyl 3,3-dimethylpent-4-ynoate,
CuI, Pd(PPh3)Cl2, Diisopropyl-amine, DMF, refluxed, 18 h, 92%; (b) 2-
((tert-butyldimethylsilyl)oxy)ethanamine, Cs2CO3, x-phos, Pd2(dba)3,
toluene, 100 oC, 18 h; (c) 4,6-dichloropyrimidine-5-carbonyl chloride,
TEA, DCM, rt, 4 h, 49%;(d) 3% HCl/EtOH, rt, 2 h, 85%; (e) TEA,
CH3CN, 80 oC, 18 h, 95%; (f) 0.5 M NH3/dioxane, rt, 18 h,79%; (g)
LiOH.H2O, THF, H2O , rt, 24 h, 10%;

Compounds were evaluated for their activity in hDGAT1
enzyme assay.16 Firstly, these compounds were tested under
single concentration. Those compounds with over 50%
inhibition activity against hDGAT1 enzyme were further
evaluated in multiple concentrations to generate IC50 value. A
variety of literatures documented left hand side
pharmacophoric groups were combined with the pentynoic
acid through a phenyl group (Table 1). Compounds 7a-7d, 7f,
7g are all inactive, while compounds 7j, 7k have modest
activity (5.5 uM and 1.9 uM respectively). Compounds 7e,
7h, 7m are more potent with IC50 of 281-468 nM. We decided
to optimized 7m because 1) It's the most active in this series;
2) It's relatively easier to make than 7h; 3) It has lower clogP
We first evaluate pharmacokinetic properties of 7m in
SD rat (Table 5). It is orally bioavailable (42%) with oral
exposure of 4105 ng.h/mL when dosed at 10 mg/kg and a
moderate clearance of 14.8 mL/min/kg. Overall, it was
explored as a lead compound.
We next sought to improve potency by substituting the
phenyl ring of linker moiety. Compounds with different
substituents at phenyl ring were designed, synthesized and
evaluated (Table 2). Small 2-substituents such as Me (25), F
(27), Cl (28), CF3 (34) all improve DGAT1 inhibitory activity.
Increasing the size of 2-substituent such as MeO (32) can
decrease activity. The 3-position at phenyl ring does not
tolerate any substitution. Compounds 26 (Me) and 30 (F) both
lost much activity. In terms of disubstitution, 3,5-subsituted
33 are deleterious to activity while 2,6-substitued improve
activity. Accordingly, compounds 29 (2,6-diMe) 35 (2-Cl-6-
Me), 36 (2-Et-6-Me), 37 (2,6-diEt), 39 (2,6-diCl) and 40 (2-F-
6-Me) are all quite active (hDGAT1 IC50: 14-35 nM). Also it
appears electron donating groups hurt activity comparing 32
(2-MeO) vs 31 (2-OCF3), and 41 (2-MeO-6-Me) vs 36 (2-Et-
value vs 7e.
Table 1 Enzyme Inhibitory Potencies for Desired Compounds
6-Me).
Table 2. SAR around the linker moiety substituent
Com
pds
%Inhibition %Inhibition
Human_DGAT1
IC50, nM
R
@50uM
@2uM
7a
7b
7c
10
3
NT
NT
NT
9
-10
21
%Inhibition hDGAT1 mDGAT1
12
Compds
R
@50uM
IC50, nM IC50, nM
7m
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
H
91
281
55
282
52
7d
7e
7f
26
NT
-1
NT
468
NT
2-methyl
104
64
3-methyl
1241
74
3762
58
NT
NT
2-Fluoro
99
2-Chloro
100
94
26
Inactive
2,6-dimethyl
3-Fluoro
106
21
12
Inactive
NT
NT
44
NT
92
7g
Inactive
NT
NT
2-trifluoromethoxy
2-methoxy
NT
387
NT
30
728
NT
24
3,5-dimethyl
2-trifluoromethyl
2-Chloro-6-methyl
2-ethyl-6-methyl
2,6-diethyl
Inactive
NT
7h
7j
86
80
NT
NT
NT
69
429
5502
1929
281
101
25
14
101
21
12
103
15
12
7k
7m
NT
91
2-ethyl
107
210
14
682
10
2,6-dichloro
2-Fluoro-6-methyl
2-methoxy-6-methyl
117
121
35
11
NT
120
96
NT: NOT TESTED
NT: NOT TESTED

We next evaluated the cell-based activity17 and
selectivity against hDGAT2 of 29 vs literature reference
compound 2 (Table 3). Compound 29 had good selectivity
against hDGAT2 and also exhibited good translation from
enzyme to inhibition of triacylglycerol synthesis in the
HEK293 cell assay. When assayed for its selectivity toward
human DGAT1 over DGAT2, it showed over 1500-fold
selectivity. When assayed for mouse DGAT1 inhibition, it
showed comparable potency to human DGAT1.
standard procedures, and the analysis of remaining was
disclosed in Table 4, compound 29 were found to be
metabolically stable in two species. Compound 29 was further
evaluated for the inhibition of clinically relevant CYP
isoforms (1A2, 2C9, 2C19, 2D6, 3A4) and no significant
inhibition was observed.
In anticipation of advancing 29 to preclinical in vivo
efficacy studies, pharmacokinetic profiling was performed in
the rat and mouse. Compound 29 has a low clearance and
moderate volume of distribution in the rat at 4.76 mL/min/kg
and 1.12 L/kg, respectively. High oral bioavailability (70%)
and a moderate half-life of 3.8 h were observed in the rat with
an oral dose of 10 mg/kg of 29 in 0.5% CMC-Na vehicle
(Table 5). Both plasma clearance and volume of distribution
in the mouse are in the moderate range at 39.3 mL/min/kg and
2.44 L/kg, respectively (Table 6). Compound 29 exhibited
rapid absorption in these two species judging by Tmax of 0.5
h in oral pharmacokinetic studies.
Table 3. Enzyme and Cellular Inhibitory Potencies for Selected
Compounds16,17
Compound
hDGAT1
IC50, nM
hDGAT2
IC50, nM
mDGAT1
IC50, nM
HEK293
EC50,nM
26
29
2
28
32
>50,000
>50,000
12
38
20
Compound 29 was found to have moderate plasma
protein binding of 86%. The in vitro metabolic stability of 29
was assessed in human and mouse liver microsomes using
Table 4. ADME properties of 29
In vitro liver
CYP inhibition
Microsomal stability
Mouse
Human
Sol.
pH=7.4
(uM)
PPB
%Bound
Human
Compd
no.
1A2, 2C9, 2C19,
2D6, 3A4
IC50(uM)
CLint
(mL/min/
kg)
CLint
(mL/min/
kg)
Remaining
(T=60 min)
Remaining
(T=60 min)
27.6, >100, 29.7,
27.2, 45.5
29
110
86.1
<38
97.9%
<9.5
97.6%
Table 5. SD Rat Pharmacokinetic properties of selected compoundsa
Compd
no.
IV(0.5mg/kg)
PO(10mg/kg)
Tmax(h) AUC(ng.h/mL)
4105
20956
Cl(mL/min/kg)
Vdss(L/Kg)
1.06
Cmax(ng/mL)
2165
F%
42
70
7mb
29c
14.8
4.76
0.5
0.5
1.12
8700
a Male Sprague-Dawley Rat Fasted
b IV formulation was 10%DMSO/70% PEG400 in water, PO formulation was 6.7% solutol/43.3% water/50% HPMC
c IV formulation was DMSO:PEG400:Water=10:40:50, PO formulation was 0.5%CMC-Na, clear solution
Table 6. Mouse Pharmacokinetic properties of 29a
Compd
no.
IV(0.5mg/kg)b
PO(10mg/kg)b
Cl(mL/min/kg)
39.3
Vdss(L/Kg)
2.44
Cmax(ng/mL)
521
Tmax(h)
0.5
AUC(ng.h/mL)
1250
F%
31
29
a Male CD-1 Mouse Fasted
b IV formulation was DMA PEG400 in 20 % HP-beta-CD(1:4:5), POformulation was 20%HP-beta-CD

Encouraged by the in vitro potency and excellent PK profile of compound 29, we tested it for efficacy in lipid tolerance test
and obesity animal model.
Since DGAT1 is highly expressed in the small intestine and catalyzes the rate final committed step in triacylglycerol synthesis,
co-dosing of DGAT1 inhibitor with an oral bolus of lipid provides a rapid confirmation of proof of mechanism. Compound 29 was
evaluated in an acute lipid challenge model measuring plasma triacylglycerols after a corn oil bolus.18 CD-1 mice were treated with
vehicle, 0.3, 1 mg/kg of 29 30 min prior to corn oil dosing. Blood samples for triacylglycerol analyses were taken at pre-dose, 0.5,
1, 2, and 4 h post-lipid challenge. Doses of 0.3, 1 mg/kg (po) of 29 were found to completely suppress plasma triacylglycerols
excursion following a lipid challenge. Both doses produced a statistically significant (p < 0.001) reduction in plasma triacylglycerol
excursion at 2 h, almost close to baseline(Fig. 2).
Figure 2. mice lipid tolerance test with 29.
On the basis of this excellent potency and efficacy in an acute PD study, compound 29 was advanced to a chronic preclinical
model of obesity.
Figure 3 Percent change in body weight in DIO mice treated with 29.
To assess its activity in a model of diet-induced obesity mouse model, compound 29 was tested for effects on body weight loss
in DIO mice (Fig. 3).19 Compound 29 was orally dosed at 10 mg/kg twice a day. Treatment for 7 days resulted in a modest but
statistically significant reduction in body weight compared to start weight and in comparison with vehicle treated control mice on
the same diet. We also measured daily food intake. As shown in Fig 4, treatment of 29 caused significant decrease in cumulative
food intake (-11%) compared with vehicle control group, this data suggested that part of the effect of 29 on body weight may be due
to reduced food intake.

Figure 4 Cumulative Food intake in DIO mice treated with 29.
In summary, a series of novel DGAT1 inhibitor derivatives were designed and synthesized, which demonstrated good in vitro
DGAT1 enzyme inhibition and cellular potency. One of the desired compounds 29 showed good ADME and PK properties. The
ability of this compound to deplete serum triacylglycerols following a corn oil bolus indicated an on-target mechanism of intestinal
DGAT1 inhibition. Furthermore, compound 29 exhibited superior efficacy in the reduction of body weight gain in obese mouse
model. Our results provided further evidence that small molecule DGAT1 inhibitors could have beneficial effects on metabolic
syndromes.
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16. hDGAT1 assay: Add 25 μl of 400 μM DG to a Flashplate. Shake gently to expand the DG to cover the bottom of each well.
Incubating at room temperature for 10 min. Add 50 μl of 0.4 mg/ml membrane (insect cell membrane over expressed hDGAT1)
to the each well of the assay plate. Add 1 μl of DMSO or serial diluted compounds. Shaking at 3000~4000 rpm at room
temperature for 10 min. Add 25 μl 4 μM [14C] oleoyl-CoA to each well of the assay plate and seal with a TopSeal-A. Shaking
at 3000~4000 rpm for 15min at 25 oC in incubator. Add 100 μl isopropanol to stop the reaction. Shaking at 3000~4000 rpm for

o
5min at room temperature. Incubated at 4 C for 1 h. Count on a TopCount Scintillation Plate Reader. The same method was
used for mDGAT1 and hDGAT2 assay with membrane of insect cells over expressed mDGAT1 and hDGAT2, respectively.
17. Jenson Qi, Wensheng Lang, Edward Giardino , Gary W. Caldwell, Charles Smith, Lisa K. Minor, Andrew L. Darrow, Gustaaf
Willemsens, Katharina DeWaepenaert, Peter Roevens, Joannes T. M. Linders, Yin Liang, and Margery A. Connelly, Journal of
Lipid Research, 2010 51:3559
18. Male CD-1 mice were obtained from Beijing Vital River Laboratory Animal Technology Co., Ltd. All mice were weighted ~30
g at study initiation and were fed a standard rodent diet ad libitum and provided free access to water. Mice were grouped
randomly by body weight (n=7~8) and then fasted overnight for 16 h with free access to water. All the groups were bled by a
cut on the tail tip for baseline plasma triacylglycerol level. 30 min later, vehicle(0.5%MC+2%Tween 80), 0.3 mg/kg and 1
mg/kg of 29 were administrated orally 30 min prior to a corn oil challenge (6 ml/kg) via oral gavage. Blood samples were
collected from the tail tipat 0.5 h, 1 h, 2 h and 4 h after the corn oil challenge for triacylglycerol levels measurement. Blood
was collected in pre labeled tubes containing K2EDTA solution. After centrifugation at 7000 rpm for 10 minutes, plasma
samples were separated. Plasma triacylglycerol levels were estimated using commercially available triacylglycerol kits.
19. C57BL/6J mice (age 6 weeks) were obtained from Beijing Vital River Laboratory Animal Technology Co., Ltd. and housed
under conditions of 12 h lights on, 12 h lights off, with food and water available ad libitum. Mice were acclimated for 2 weeks
with normal diet. At the beginning of the study, mice were administered a high fat content diet (D12492i, 60 kcal% fat,5.2
kcal/g), obtained from Research Diets Inc. for approximately 14 weeks. Mice were weighed twice a week and individually
housed when body weight above 38 g. Mice with 40~50 g body weight were selected and randomly grouped by weight
(n=7~8). Before compound treatment, mice were conditioned to oral gavage and daily vehicle(0.5%MC+2%Tween 80)
administration for one week. Pharmacological treatments were administered twice a day at 09:00 and 16:30. PF04620110 (2)
and 29 were administered po by gavage, at 30 mg/kg b.i.d, and 10 mg/kg b.i.d, respectively. Food intake and body weight were
recorded every day. On day 7, mice were humanely euthanized under CO2-O2 anesthesia. Difference between groups were
analyzed by one way ANOVA followed by the Tukey’s multiple comparison test.

Highlights:
1) We have described a novel class of orally bioavailable DGAT1 inhibitors.
2) We introduced alkyne to replace cyclohexane ring as linker in drug design.
3) One of the desired compound 29 exhibited superior efficacy in DIO animal model.

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Disocvery of dimethyl pent-4-ynoic acid
derivatives, as potent and orally bioavailable
DGAT1 inhibitors that suppress body weight
in diet-induced mouse obesity model.
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Tao Yu, Chengde Wu, NengYang Shih, Qi Li, Chichung Chan, He Pan, Dan Yao, Yan Pan, Wei
Liang, Liang Shen, Hui Zhao, Jian Li, Shuhui Chen

20.
E-mail address: yu_tao_001391@wuxiapptec.com.