Design and synthesis of small molecule glycerol 3-phosphate acyltransferase inhibitors

Article abstract of DOI:10.1021/jm900251a

The incidence of obesity and other diseases associated with an increased triacylglycerol mass is growing rapidly, particularly in the United States. Glycerol 3-phosphate acyltransferase (GPAT) catalyzes the ratelimiting step of glycerolipid biosynthesis, the acylation of glycerol 3-phosphate with saturated long-chain acyl-CoAs. In an effort to produce small molecule inhibitors of this enzyme, a series of benzoic and phosphonic acids was designed and synthesized. In vitro testing of this series has led to the identification of several compounds, in particular 2-(nonylsulfonamido)benzoic acid (15g), possessing moderate GPAT inhibitory activity in an intact mitochondrial assay.

Full text of DOI:10.1021/jm900251a

J. Med. Chem. 2009, 52, 3317–3327
3317
Design and Synthesis of Small Molecule Glycerol 3-Phosphate Acyltransferase Inhibitors
Edward A. Wydysh, Susan M. Medghalchi, Aravinda Vadlamudi, and Craig A. Townsend*
Department of Chemistry, The Johns Hopkins UniVersity, Remsen Hall, 3400 North Charles Street, Baltimore, Maryland 21218
ReceiVed February 27, 2009
The incidence of obesity and other diseases associated with an increased triacylglycerol mass is growing
rapidly, particularly in the United States. Glycerol 3-phosphate acyltransferase (GPAT) catalyzes the rate-
limiting step of glycerolipid biosynthesis, the acylation of glycerol 3-phosphate with saturated long-chain
acyl-CoAs. In an effort to produce small molecule inhibitors of this enzyme, a series of benzoic and
phosphonic acids was designed and synthesized. In vitro testing of this series has led to the identification
of several compounds, in particular 2-(nonylsulfonamido)benzoic acid (15g), possessing moderate GPAT
inhibitory activity in an intact mitochondrial assay.
Introduction
mtGPAT2).12,13 mtGPAT1 displays a strong preference for
incorporating palmitoyl-CoA (16:0), thereby primarily producing
saturated phospholipids, whereas the other three enzymes are
not selective.13,14 For recombinant mouse mtGPAT1, activity
is 2-fold greater with palmitoyl-CoA than with various unsatur-
ated chains 18 and 20 carbons in length,15 and in rat liver,
kidney, and heart, mtGPAT1 incorporates palmitoyl CoA 3-10
times more effectively than other long-chain saturated or
unsaturated acyl-CoAs.14,16-18 Of the four isoforms, only
mtGPAT1 is affected by changes in diet or exercise. When
excess calories are available from a high-carbohydrate diet,
mtGPAT1 mRNA expression increases, resulting in greater
mtGPAT1 activity.19-21 Mice that remain stationary for 10 hours
following a prolonged exercise regimen experience an increase
in mtGPAT1 activity compared to mice that did not exercise at
all, resulting in a significant overshoot of triacylglycerol (TAG)
synthesis.22
mtGPAT1-deficient mice exhibit lower hepatic TAG levels
and secrete less very low density lipoprotein (VLDL) than
control mice.23 In contrast, rat hepatocytes with 2.7-fold
increased mtGPAT1 activity demonstrated a significant increase
in de novo synthesis of diacylglycerol.24 Overexpression of
mtGPAT1 in vivo, as expected from the previous result, causes
the levels of accumulated TAG and diacylglycerol (DAG) in
mouse liver to rise dramatically to 12-fold and 7-fold that of
normal levels.25 In addition to producing a certain amount of
TAG dependent on the amount of active enzyme present,
mtGPAT1 activity is essential for controlling the partitioning
of fatty-acyl CoAs to ꢀ-oxidation or glycerolipid synthesis.
Both mtGPAT1 and carnitine palmitoyltransferase-1 (CPT-
1), the enzyme that catalyzes the rate-limiting step of ꢀ-oxida-
tion, are located on the outer mitochondrial membrane.26 This
suggests that there is a competition between these enzymes for
fatty acyl-CoA substrates. AMP-activated protein kinase (AMPK),
which inactivates acetyl-CoA carboxylase (ACC) by phospho-
rylation, appears to acutely regulate both of these enzymes.
Inactivation of ACC by AMPK prevents the buildup of malonyl-
CoA, an allosteric suppressor of CPT-1, resulting in an increase
in ꢀ-oxidation.27 AMPK inhibits mtGPAT1 as well, thereby
decreasing the amount of TAG produced.28 The relationship
between these two processes has been demonstrated in vivo.
Feeding mtGPAT1-knockout mice a high-fat, high-sugar diet
to induce obesity resulted in an increase in oxidation as the
long-chain acyl-CoA substrates were partitioned away from the
TAG synthetic pathway toward CPT-1 and ꢀ-oxidation.29
Obesity is currently estimated by the World Health Organiza-
tion to affect at least 400 million adults worldwide. In the U.S.
alone, approximately two-thirds of adults are overweight or
obese.1 Various diseases are associated with obesity, including
type 2 diabetes, hypertension, cardiovascular diseases, nonal-
coholic fatty liver disease, and certain types of cancer. Even
though there is a growing need for antiobesity therapeutics, there
are only two drugs approved for long-term use in the U.S.
Orlistat functions by blocking the absorption of fat from the
diet,2 and sibutramine affects the central nervous system,
reducing energy intake and increasing energy use.3 Unfortu-
nately, each of these drugs displays limited efficacy and
produces undesirable side effects. Antiobesity drugs currently
in development utilize a wide variety of mechanisms, involving
both central and peripheral targets. Alteration of lipid metabo-
lism, by decreasing the de novo synthesis of triglycerides while
increasing oxidation of stored fats, is a peripheral mechanism.
This approach, based on weight loss effects observed with the
compounds C75,4 cerulenin,5 and hGH(177-191),6 may be highly
valuable in developing antiobesity drugs.a
The mitochondrial isoform of glycerol-3-phosphate acyltrans-
ferase-1 (mtGPAT) catalyzes the esterification of long-chain
acyl-CoAs with sn-glycerol-3-phosphate to produce lysophos-
phatidic acid (LPA). This reaction constitutes the first committed
and rate-limiting step of glycerolipid biosynthesis.7,8 The
purported mechanism of this reaction is similar to that of a serine
protease, with the primary hydroxyl group of glycerol-3-
phosphate taking the place of serine in the catalytic triad.9 Next,
LPA is esterified further to produce phosphatidic acid, a
precursor of various lipids, including triacylglycerol (TAG), the
main component of animal fat. In addition to obesity, high TAG
levels in the bloodstream have been linked to several diseases,
notably atherosclerosis and pancreatitis.10,11
There are four known isoforms of GPAT, two microsomal
isoforms located in the endoplasmic reticulum (GPAT3 and
GPAT4) and two located in mitochondria (mtGPAT1 and
* To whom correspondence should be addressed. Phone: (410) 516-7444.
Fax: (410) 261-1233. E-mail: ctownsend@jhu.edu.
a Abbreviations: GPAT, glycerol 3-phosphate acyltransferase; DIO, diet-
induced obese; mtGPAT, mitochondrial glycerol 3-phosphate acyltrans-
ferase; LPA, lysophosphatidic acid; TAG, triacylglycerol; VLDL, very low
density lipoprotein, DAG, diacylglycerol; CPT-1, carnitine palmitoyltrans-
ferase-1; AMPK, AMP-activated protein kinase; ACC, acetyl-CoA car-
boxylase; FAS, fatty acid synthase.
10.1021/jm900251a CCC: $40.75
2009 American Chemical Society
Published on Web 04/23/2009

3318 Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10
Wydysh et al.
Scheme 1a
Figure 1. Comparison of the proposed GPAT transition state (A) to
the basic inhibitor design (B).
mtGPAT1 overexpression in rat hepatocytes produced an 80%
reduction in fatty acid oxidation coupled to an increase in
phospholipid biosynthesis.24 Overexpression in vivo resulted in
a decrease in ꢀ-oxidation as well.25
The evidence suggesting that a drop in mtGPAT1 activity
leads to a decrease in TAG levels as well as an increase in the
amount of ꢀ-oxidation suggests that inhibition of this enzyme
with a small molecule could be an effective treatment for
obesity, diabetes, and other health problems associated with
increased TAG synthesis. As there are no such studies of small
molecule mtGPAT1 inhibitors described in the literature, we
set out to design, synthesize, and test a GPAT inhibitor as a
potential weight loss strategy.
a Reaction conditions: (a) NBS, hν, CH3CN; (b) NaN3, EtOH, reflux;
(d) C9H19SO2Cl or C5H11SO2Cl, pyridine, CH2Cl2, 0 °C to rt; (e) K+O-t-
Bu, Et2O, H2O, 0 °C to rt.
Scheme 2a
Chemistry. The fundamental design of the compounds
comprised structures with a negative charge at physiological
pH to mimic the phosphate group of glycerol-3-phosphate and
a long saturated chain to mimic the chain of palmitoyl-CoA,
the substrate for which mtGPAT1 demonstrates a strong
preference.14 A sulfonamide linker was chosen to represent a
stable mimic of the presumed intermediate or transition state
of the acylation reaction catalyzed by GPAT (Figure 1).
The putative glycerol-3-phosphate binding pocket, as deter-
mined in GPAT isolated from squash chloroplasts, consists of
several conserved positively charged amino acids, namely His-
139, Lys-193, His-194, Arg-235, and Arg-237 in the squash
enzyme.9 This conserved pocket is believed to closely interact
with the phosphate of glycerol-3-phosphate and could play an
integral role in binding a carboxylate or phosphonate in an
inhibitor. The conserved catalytic histidine, which is thought
to deprotonate the primary hydroxyl group involved in the
acylation reaction, could interact favorably with the relatively
acidic sulfonamide hydrogen (Figure 1). Furthermore, the
saturated chain of the alkyl sulfonamide would serve as a
palmitoyl-CoA C16 mimic, ideally occupying the hydrophobic
palmitoyl-CoA binding site extending from the glycerol-3-
phosphate binding site in the classical view of a bisubstrate
analogue.
The spatial relationship between the acyl-CoA and glycerol-
3-phosphate in the mammalian GPAT active site is not known,
however, so different linkers between the two moieties had to
be examined. It was thought the most efficient way to do this
would be to synthesize benzoic acids and phosphonic acids with
saturated alkyl sulfonamides at each position on the aromatic
ring. The distances between the sulfonamide and the carboxylate
or phosphonate could also be altered by placing each group one
or several methylene units from the ring. The most efficient
synthetic pathway for the production of the benzoic acids was
the coupling of a primary amine already present on a benzoic
acid methyl ester to the alkyl sulfonyl chloride. Saponification
of the ester to liberate the carboxylic acid was typically the final
a Reaction conditions: (a) NH3, MeOH, reflux; (b) NaH, RSO2Cl, DMF,
0 °C to rt; (c) NaOH, THF/H2O, 0 °C to rt.
step in the synthetic sequence. In the case of the phosphonic
acids, the phosphonates were installed through an Arbuzov
reaction on a primary bromide or through aryl halide coupling
reactions catalyzed by tetrakis(triphenylphosphine)pal-
ladium(0).30 The protected amine already present was then
deprotected, coupled to the sulfonyl chloride, and the ethyl
phosphonate was deprotected to yield the phosphonic acid. The
compounds produced from these several routes allowed for the
determination of a preliminary SAR from the GPAT inhibition
assay.
The first series of compounds was derived from the variously
substituted methyl methylbenzoates (Scheme 1). The meta- and
para-amines were made by following a literature protocol.31
Following radical bromination of the methyl group with NBS
in CH3CN, the bromide was displaced by refluxing with NaN3
in EtOH. Under Staudinger conditions, the azide was reduced
to the free amine 3, which could then be coupled to 1-pentane-
or 1-nonanesulfonyl chloride, prepared as described.32 Finally,
the methyl ester 4 was converted to the carboxylate product 5
by reaction with potassium t-butoxide in Et2O with water
present.
The ortho-substituted carboxylates required a different ap-
proach than the meta- and para-compounds (Scheme 2).
Indolinone 6, formed in a reaction between the ortho-bromide
and ammonia gas in MeOH,33 was coupled to the alkane
sulfonyl chlorides with NaH in DMF, and the resulting γ-lactam
bond was readily cleaved with NaOH in THF/H2O to produce
carboxylic acids 5e and 5f.

Synthesis and ActiVity of GPAT Inhibitors
Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10 3319
Scheme 5a
Scheme 3a
a Reaction conditions: (a) RSO2Cl, pyridine, CH2Cl2, 0 °C to rt; (b)
K+O-t-Bu, Et2O, H2O, 0 °C to rt.
Scheme 6a
a Reaction conditions: (a) NBS, hν, CH3CN; (b) P(OEt)3, reflux; (c)
H2SO4, EtOH, reflux; (d) C9H19SO2Cl or C5H11SO2Cl, pyridine, CH3CN, 0
°C to rt; (e) TMSBr, CH2Cl2, rt.
Scheme 4a
a Reaction conditions: (a) diethyl phosphite, Et3N, Pd(PPh3)4, EtOH,
reflux; (b) H2SO4, EtOH, reflux; (c) C8H17SO2Cl, Et3N, CH2Cl2, 0 °C to rt;
(d) TMSBr, CH2Cl2, rt.
phosphonic acid moiety was revealed by treatment with TMSBr
in CH2Cl2 followed by methanolysis.
Compounds 15a-i were synthesized by coupling the com-
mercially available starting aniline with a variety of sulfonyl
chlorides (Scheme 4). The resulting sulfonamides 14a-i were
then converted to the final products by hydrolysis with potassium
t-butoxide and water in ether. Aromatic sulfonyl chlorides were
used as well as the saturated C9 chain in an attempt to mimic
the CoA portion of the acyl-CoA substrate, as opposed to the
alkyl chain.
Compounds 17a-f were designed to probe the effect of
linkers of different length in the aryl sulfonamide portion of
the molecule. These were produced in the same manner as
15a-i, starting with the commercially available aniline and
coupling to either benzylsulfonyl chloride or phenylethylsulfonyl
chloride with pyridine in methylene chloride to yield sulfona-
mides 16a-f (Scheme 5). The methyl esters were then converted
to the carboxylic acids 17a-f with potassium t-butoxide and
water in ether.
The synthesis of aryl phosphonic acids 21a-c is shown in
Scheme 6. Aryl bromide 18 underwent palladium-catalyzed aryl
halide coupling with diethyl phosphite to install the phosphonate
functionality.30 The aniline was then deprotected by refluxing
a Reaction conditions: (a) RSO2Cl, pyridine, CH2Cl2, 0 °C to rt; (b)
K+O-t-Bu, Et2O, H2O, 0 °C to rt.
The synthesis of the alkyl phosphonates 13a-f commenced
with the protection of the starting toluidines as the bis-acylated
aniline 8 (Scheme 3).34 Free-radical bromination with NBS in
CH3CN afforded benzyl bromide 9, which was converted to
phosphonate 10 through Arbuzov reaction with triethyl phos-
phite. The aniline was unmasked by exposure to a refluxing
acidic solution of EtOH. Following coupling of the amine with
the alkane sulfonyl chloride to produce sulfonamide 12, the

3320 Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10
Wydysh et al.
Scheme 7a
Table 1. In Vitro Anti-mtGPAT1 Activity of Sulfonamides 5a-f and
13a-f
compd
X
Y
n
IC50 (µM) ( SD
5a
5b
5c
5d
5e
5f
13a
13b
13c
13d
13e
13f
p-CO2H
p-CO2H
m-CO2H
m-CO2H
o-CO2H
o-CO2H
p-CH2PO3H2
p-CH2PO3H2
m-CH2PO3H2
m-CH2PO3H2
o-CH2PO3H2
o-CH2PO3H2
C5H11
C9H19
C5H11
C9H19
C5H11
C9H19
C5H11
C9H19
C5H11
C9H19
C5H11
C9H19
1
1
1
1
1
1
0
0
0
0
0
0
252 ( 6.0
129 ( 18.5
310 ( 6.0
83.5 ( 4.7
217 ( 47.3
66.5 ( 3.2
148 ( 29.8
81.3 ( 14.3
141 ( 28.0
62.8 ( 1.9
129 ( 26.2
81.1 ( 16.4
a Reaction conditions: (a) RSO2Cl, pyridine, CH2Cl2, 0 °C to rt; (b)
K+O-t-Bu, Et2O, H2O, 0 °C to rt.
Table 2. In Vitro Anti-mtGPAT1 Activity of Sulfonamides 15a-i and
17a-f
in acidic ethanol, and the free amine was coupled with
commercially available octanesulfonyl chloride to produce 20.
The final compound was then obtained by deprotecting the
diethyl phosphonate with TMSBr.
Compounds 24a-c, based on 15g, were designed as probes
to examine the effect of installing different length alkylsulfona-
mides on the ortho-substituted analogues (Scheme 7). It was
believed that the compound with the saturated C16-chain (24c)
would exhibit significantly greater inhibitory activity than 15g,
as the enzyme demonstrates a marked preference for palmitoyl-
CoA over other long-chain acyl-CoAs.14 Compounds 24d-f
were designed to examine the role of an electronegative group
at the 4-position of the benzene ring, which could possibly
mimic the electron density of the secondary alcohol on glycerol-
3-phosphate. All of these compounds, 24a-f were produced
with the same reaction sequence used to produce 15a-f and
17a-f.
compd
X
Y
IC50 (µM) ( SD
15a
15b
15c
15d
15e
15f
15g
15h
15i
17a
17b
17c
17d
17e
17f
p-CO2H
p-CO2H
p-CO2H
m-CO2H
m-CO2H
m-CO2H
o-CO2H
o-CO2H
o-CO2H
p-CO2H
p-CO2H
m-CO2H
m-CO2H
o-CO2H
o-CO2H
C9H19
Ph
4-ClPh
C9H19
Ph
4-ClPh
C9H19
Ph
4-ClPh
CH2Ph
C2H4Ph
CH2Ph
C2H4Ph
CH2Ph
C2H4Ph
88.9 ( 13.1
151 ( 19.1
108 ( 4.2
73.9 ( 8.9
138 ( 27.4
75.7 ( 3.8
24.7 ( 2.1
146 ( 9.4
107 ( 8.0
221 ( 39.7
206 ( 42.2
178 ( 30.7
164 ( 14.3
140 ( 4.1
152 ( 14.7
Results and Discussion
All benzoic acids and phosphonic acids produced were then
evaluated for their ability to inhibit the acylation of glycerol-
3-phosphate in vitro. The acylation reaction between 14C-labeled
glycerol-3-phosphate and palmitoyl-CoA, initiated by adding
mtGPAT, was measured in the presence of varying concentra-
tions of the inhibitor by scintillation counting.35 Each reaction
was performed in triplicate, and the IC50 values were then
calculated based on the amount of inhibitor needed to produce
50% inhibition compared to the DMSO vehicle control. Results
are summarized in Tables 1-3.
Data obtained from benzoic acids 5a-f indicate that in all
cases, regardless of the position of the carboxylate with respect
to the sulfonamide, the longer C9 alkyl chain resulted in greater
inhibition than the C5 saturated chain. The most effective
orientation between the acid and sulfonamide appeared to be
ortho-substitution, as 5f (IC50 ) 66.5 µM) is a better inhibitor
than either 5b (IC50 ) 129 µM) or 5d (IC50 ) 83.5 µM). The
assay data from phosphonic acids 13a-f also indicated that the
longer C9 alkyl chain is more effective. In this series of
compounds, however, there is no significant difference in
activity between the different orientations of the phosphonic
acid and the alkyl sulfonamide moiety. The most active
compound of this class was 13d (IC50 ) 62.8 µM), the meta-
substituted phosphonic acid, though not by much over 13b
(IC50 ) 81.3 µM) and 13f (IC50 ) 81.1 µM).
Table 3. In Vitro Anti-mtGPAT1 Activity of Sulfonamides 21a-c and
24a-f
compd
X
Y
Z
IC50 (µM) ( SD
21a
21b
21c
24a
24b
24c
24d
24e
24f
p-PO3H2
m-PO3H2
o-PO3H2
CO2H
C8H17
C8H17
C8H17
CH3
C14H29
C16H33
C9H19
C8H17
C8H17
H
H
H
H
H
H
Cl
OH
F
95.3 ( 10.9
72.4 ( 15.5
73.6 ( 7.1
132 ( 21.2
17.4 ( 1.2
18.3 ( 1.9
31.8 ( 1.9
116 ( 12.4
89.0 ( 7.8
CO2H
CO2H
CO2H
CO2H
CO2H
Compounds 15b, 15c, 15e, 15f, 15 h, 15i, and 17a-f were
designed to examine the possibility of an appropriately substi-
tuted benzene ring serving as a mimic for the coenzyme A
portion of the fatty acyl-CoA natural substrate. The distance
between the benzene ring and the sulfonamide sulfur does not

Synthesis and ActiVity of GPAT Inhibitors
Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10 3321
General Procedure for 4a-d. To a stirring solution of the
appropriate amine 3a-c (1.2 mmol) in CH2Cl2 (4 mL) at 0 °C, the
sulfonyl chloride (1.3 mmol) was added dropwise, followed by Et3N
(1.3 mmol). The reaction mixture was allowed to warm to room
temperature, where it was stirred for 2-3 h. Saturated NH4Cl
solution was added to quench the reaction, and the mixture was
extracted with 3 × 10 mL CH2Cl2. The combined organic layers
were dried over MgSO4, concentrated in vacuo, and the products
were purified by flash chromatography (20% EtOAc in hexanes).
appear to have a significant effect on the inhibitory activity of
these compounds, as there is effectively no difference between
one methylene and two methylene linkers. It is apparent,
however, that the ortho-substituted compounds containing these
linker methylenes (17e-f) are slightly more effective than the
other substituted benzoic acids (17a-d). For the meta- and para-
compounds, inhibitory activity is greater when the benzene ring
is directly attached to the sulfur, although the ortho-compounds
are all similar. The addition of a para-chloride on the benzene
ring does lead to increases in activity for the para- (15c), meta-
(15f), and ortho-compounds (15i). Compounds 15a, 15d, and
15g were easily obtainable targets, which allowed for examina-
tion of the effect of the methylene linker between the benzene
ring and the sulfonamide in 5a-f. For every substitution, these
compounds were the most effective GPAT inhibitors, with the
ortho-compound (15g) demonstrating the greatest activity
(IC50 ) 24.7 µM). On the basis of these results, the long alkyl
chain is likely a more effective fatty-acyl CoA recognition
element for the enzyme than a simple benzene ring.
In view of the increased inhibitory activity of 15g, two other
compound series were prepared. The first, 21a-c, probes the
effectiveness of an aryl phosphonic acid in place of the benzoic
acid moiety. In vitro, the ortho-substituted acid (21c) is less
active than 15g, and substitution of the phosphonic acid moiety
does not appear to significantly affect activity (Table 3). The
other compounds produced (24a-f) indicate the importance of
chain length of the alkyl sulfonamide as well as the effect of
adding heteroatoms para- to the sulfonamide. It appears that
the longer chain is very important to the activity of these
compounds, as a C1-chain (24a) results in significantly less in
vitro activity than the C9 chain. Compounds 24b and 24c were
produced to determine if the naturally favored C16 chain is
preferred in these compounds over other chain lengths, including
the C14 chain. In this case, there is no observed preference for
the C16 compound over other long chains, in contrast to that
observed with the natural acyl-CoA substrates.14
1
Methyl 4-(Pentylsulfonamidomethyl)benzoate 4a. H NMR
(CDCl3) δ 8.02 (d, J ) 8.1 Hz, 2H), 7.42 (d, J ) 8.1 Hz, 2H),
4.85 (br s, 1H), 4.35 (s, 2H), 3.92 (s, 3H), 2.93 (t, J ) 8.4 Hz,
2H), 1.76 (m, 2H), 1.30 (m, 4H), 0.89 (t, J ) 6.9 Hz, 3H). 13C
NMR (CDCl3) δ 166.6, 142.1, 130.0, 129.8, 127.6, 53.4, 52.1, 46.7,
30.2, 23.2, 22.1, 13.6.
Methyl 4-(Nonylsulfonamidomethyl)benzoate 4b. 1H NMR
(DMSO-d6) δ 7.93 (d, J ) 8.0 Hz, 2H), 7.71 (t, J ) 6.4 Hz, 1H),
7.49 (d, J ) 8.0 Hz, 2H), 4.22 (d, J ) 6.4 Hz, 2H), 3.84 (s, 3H),
2.90 (t, J ) 8.0 Hz, 2H), 1.56 (m, 2H), 1.23 (m, 12H), 0.85 (t, J
) 6.4 Hz, 3H). 13C NMR (DMSO-d6) δ 165.9, 144.2, 129.1, 128.4,
127.7, 52.0, 51.5, 45.4, 31.2, 28.6, 28.5, 28.4, 27.4, 23.0, 22.0, 13.8.
1
Methyl 3-(Pentylsulfonamidomethyl)benzoate 4c. H NMR
(CDCl3) δ 8.01 (s, 1H), 7.98 (d, J ) 7.6 Hz, 1H), 7.57 (d, J ) 8.0
Hz, 1H), 7.44 (t, J ) 7.8 Hz, 1H), 4.81 (t, J ) 6.0 Hz, 1H), 4.35
(d, J ) 6.0 Hz, 2H), 3.92 (s, 3H), 2.92 (t, J ) 8.0 Hz, 2H), 1.76
(m, 2H), 1.28 (m, 4H), 0.88 (t, J ) 7.2 Hz, 3H). 13C NMR (CDCl3)
δ 166.6, 137.5, 132.3, 130.7, 129.1, 128.9, 128.8, 53.4, 52.2, 46.7,
30.2, 23.2, 22.1, 13.6.
Methyl 3-(Nonylsulfonamidomethyl)benzoate 4d. 1H NMR
(CDCl3) δ 8.01 (s, 1H), 7.98 (d, J ) 7.6 Hz, 1H), 7.57 (d, J ) 7.6
Hz, 1H), 7.44 (t, J ) 7.6 Hz, 1H), 4.80 (t, J ) 6.0 Hz, 1H), 4.35
(d, J ) 6.0 Hz, 2H), 3.92 (s, 3H), 2.93 (t, J ) 8.0 Hz, 2H), 1.75
(m, 2H), 1.25 (m, 12H), 0.88 (t, J ) 6.4 Hz, 3H). 13C NMR (CDCl3)
δ 166.6, 137.5, 132.3, 130.7, 129.1, 128.9, 128.8, 53.4, 52.2, 46.7,
31.7, 29.2, 29.1, 29.0, 28.1, 23.5, 22.6, 14.0.
General Procedure for 5a-d. To a stirring suspension of
potassium t-butoxide (5.88 mmol) in Et2O (15 mL) cooled to 0 °C
was added water (1.4 mmol) via syringe. The slurry was stirred
for 5 min, and 4a-d (0.67 mmol) was added. The mixture was
stirred at room temperature until starting material disappeared by
TLC analysis (20% EtOAc in hexanes). Ice water was added until
two clear layers formed. The aqueous layer was separated and
acidified with 1 M HCl. The product was then extracted with Et2O
(3 × 20 mL) and evaporated in vacuo to afford 5a-d.
Conclusions
The first preliminary structure-activity relationship of mam-
malian GPAT inhibition has been constructed, utilizing in vitro
assay data from several simple sulfonamide-containing benzoic
acids and phosphonic acids. It appears that a medium- to long-
chain alkyl sulfonamide is necessary for inhibitory activity, but
there is not a significant preference for the naturally favored
palmitoyl chain (C16) over other shorter saturated chains.
Replacement of the benzoic acid of 15g with an aryl phosphonic
acid moiety results in decreased inhibitory activity, as does the
presence of chloride, fluoride, or a hydroxyl group at the
5-position of the benzene ring. The best inhibitor obtained from
this study, which possesses modest inhibitory activity in vitro,
has been evaluated in relevant biological systems, with the
results to be reported in the near future.
4-(Pentylsulfonamidomethyl)benzoic Acid 5a. mp ) 188-189
°C. 1H NMR (MeOD) δ 8.02 (d, J ) 8.3 Hz, 2H), 7.50 (d, J ) 8.3
Hz, 2H), 4.31 (s, 2H), 2.95 (t, J ) 8.1 Hz, 2H), 1.73 (m, 2H), 1.33
(m, 4H), 0.91 (t, J ) 6.9 Hz, 3H). 13C NMR (MeOD) δ 169.5,
145.0, 131.1, 131.0, 128.8, 53.6, 47.2, 31.4, 24.3, 23.2, 14.0. HRMS
(FAB) calcd for C13H20NO4S [M + H]+, 286.11131; found,
286.1111. Anal. (C13H19NO4S) C, H, N.
4-(Nonylsulfonamidomethyl)benzoic Acid 5b. mp ) 178-180
°C. 1H NMR (MeOD) δ 8.03 (d, J ) 8.3 Hz, 2H), 7.51 (d, J ) 8.3
Hz, 2H), 4.32 (s, 2H), 2.94 (t, J ) 7.8 Hz, 2H), 1.71 (m, 2H), 1.30
(m, 12H), 0.92 (t, J ) 6.9 Hz, 3H). 13C NMR (DMSO-d6) δ 167.0,
143.6, 129.5, 129.3, 127.5, 51.5, 45.4, 31.2, 28.6, 28.5, 28.4, 27.4,
23.0, 22.0, 13.9. HRMS (FAB) calcd for C17H28NO4S [M + H]+,
342.17391; found, 342.17447. Anal. (C17H27NO4S·1/4(H2O)) C, H,
N.
Experimental Section
3-(Pentylsulfonamidomethyl)benzoic Acid 5c. mp ) 160-161
1
General Methods. 1H and 13C NMR spectra were measured on
a Bruker 300 or 400 MHz NMR spectrometer. Melting points were
determined on a Thomas-Hoover capillary melting point apparatus
and are uncorrected. Column chromatography was carried out on
silica gel 60 (Merck, 230-400 mesh ASTM). All solvents used
for reactions were distilled prior to use (Et2O and THF over Na/
benzophenone, CH2Cl2 and CH3CN over CaH). High resolution
mass spectra were obtained at the Mass Spectrometry Laboratory,
The Johns Hopkins University, Baltimore, MD. Elemental analyses
(C, H, N) were performed by Atlantic Microlab, Norcross, GA and
were within 0.4% of calculated values.
°C. H NMR (MeOD) δ 8.08 (s, 1H), 7.97 (d, J ) 7.8 Hz, 1H),
7.63 (d, J ) 7.8 Hz, 1H), 7.48 (t, J ) 7.8 Hz, 1H), 4.31 (s, 2H),
2.92 (t, J ) 8.1 Hz, 2H), 1.72 (m, 2H), 1.33 (m, 4H), 0.91 (t, J )
6.9 Hz, 3H). 13C NMR (MeOD) δ 169.5, 140.2, 133.5, 132.3, 130.1,
129.8, 129.7, 53.6, 47.1, 31.4, 24.3, 23.1, 14.0. HRMS (FAB) calcd
for C13H18NO3S [M - OH]+, 268.10074; found, 268.09988. Anal.
(C13H19NO4S) C, H, N.
3-(Nonylsulfonamidomethyl)benzoic Acid 5d. mp ) 150-151
1
°C. H NMR (MeOD) δ 8.08 (s, 1H), 7.97 (d, J ) 7.6 Hz, 1H),
7.63 (d, J ) 7.6 Hz, 1H), 7.48 (t, J ) 7.6 Hz, 1H), 4.31 (s, 2H),
2.91 (t, J ) 8.0 Hz, 2H), 1.70 (m, 2H), 1.28 (m, 12H), 0.92 (t, J

3322 Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10
Wydysh et al.
) 7.2 Hz). 13C NMR (MeOD) δ 169.5, 140.2, 133.5, 132.3, 130.1,
129.9, 129.7, 53.7, 47.2, 32.9, 30.4, 30.3, 30.1, 29.2, 24.6, 23.6,
14.4. HRMS (FAB) calcd for C17H28NO4S [M + H]+, 342.17391;
found, 342.17333. Anal. (C17H27NO4S) C, H, N.
for 18 h with a reflux condenser heated to 50 °C. Reaction progress
was monitored by TLC (30% EtOAc in hexanes). The reaction
mixture was then cooled, and P(OEt)3 was removed in vacuo. The
product was then purified by flash chromatography (2% MeOH in
CHCl3).
General Procedure for 7a-b. Compound 6 (1.5 mmol) was
added to DMF (8 mL), and the solution was cooled to 0 °C. NaH
(1.65 mmol) was added, followed by the sulfonyl chloride (1.8
mmol), and the mixture was stirred and allowed to warm to room
temperature. Reaction progress was monitored by TLC (25% MeOH
in CHCl3). When complete, saturated ammonium chloride solution
was added (80 mL), the product was extracted with EtOAc (3 ×
20 mL), dried over MgSO4, and evaporated in vacuo. The product
was purified by flash chromatography (2% MeOH in CHCl3).
2-(Pentylsulfonyl)isoindolin-1-one 7a. 1H NMR (DMSO-d6) δ
7.81 (t, J ) 7.5 Hz, 1H), 7.76 (d, J ) 7.5 Hz, 1H), 7.68 (d, J ) 7.5
Hz, 1H), 7.59 (t, J ) 7.5 Hz, 1H), 4.94 (s, 2H), 3.60 (t, J ) 7.8
Diethyl N,N-4-diacetylanilinephosphonate 10a. 1H NMR
(CDCl3) δ 7.39 (dd, J ) 8.4, 2.4 Hz, 2H), 7.07 (d, J ) 8.4 Hz,
2H), 4.02 (m, 4H), 3.17 (d, J ) 21.6 Hz, 2H), 2.25 (s, 6H), 1.22
(t, J ) 6.8 Hz, 6H). 13C NMR (CDCl3) δ 172.7, 138.1 (d, J ) 3.6
Hz), 132.7 (d, J ) 6.5 Hz), 131.1 (d, 6.5 Hz), 128.7 (d, 3.3 Hz),
62.1 (d, 6.6 Hz), 33.4 (d, J ) 137.7 Hz), 27.7, 16.2 (d, J ) 5.9
Hz).
Diethyl N,N-3-diacetylanilinephosphonate 10b. 1H NMR
(CDCl3) δ 7.30 (t, J ) 7.6 Hz, 1H), 7.24 (d, J ) 7.6 Hz, 1H), 7.03
(s, 1H), 6.94 (d, J ) 8.4 Hz, 1H), 3.91 (m, 4H), 3.06 (d, J ) 21.6
Hz, 2H), 2.16 (s, 6H), 1.13 (t, J ) 6.8 Hz, 6H). 13C NMR (CDCl3)
δ 172.4, 139.1 (d, J ) 3.1 Hz), 133.4 (d, J ) 8.8 Hz), 129.8 (d, J
) 3.6 Hz), 129.8 (d, J ) 3.7 Hz), 129.4 (d, J ) 3.0 Hz), 126.8 (d,
J ) 3.6 Hz), 61.8 (d, J ) 6.9 Hz), 33.0 (d, J ) 137.4 Hz), 26.4,
16.0 (d, J ) 5.9 Hz).
Hz, 2H), 1.72 (m, 2H), 1.32 (m, 4H), 0.83 (t, J ) 7.2 Hz, 3H). 13
C
NMR (CDCl3) δ 167.0, 141.2, 133.9, 129.8, 128.8, 124.9, 123.3,
53.2, 49.6, 30.0, 22.4, 21.9, 13.5.
2-(Nonylsulfonyl)isoindolin-1-one 7b. 1H NMR (DMSO-d6) δ
7.82 (t, J ) 7.5 Hz, 1H), 7.77 (d, J ) 7.5 Hz, 1H), 7.69 (d, J ) 7.5
Hz, 1H), 7.59 (t, J ) 7.5 Hz), 4.94 (s, 2H), 3.60 (t, J ) 8.1 Hz,
2H), 1.71 (m, 2H), 1.36 (m, 2H), 1.21 (m, 10H), 0.83 (t, J ) 6.3
Hz, 3H). 13C NMR (CDCl3) δ 167.1, 141.2, 134.0, 130.0, 128.9,
125.1, 123.4, 53.3, 49.6, 31.7, 29.1, 29.0, 28.9, 28.0, 22.9, 22.5,
14.0.
Diethyl N,N-2-Diacetylanilinephosphonate 10c. 1H NMR
(CDCl3) δ 7.60 (d, J ) 7.6 Hz, 1H), 7.35 (m, 2H), 7.09 (d, J ) 7.6
Hz, 1H), 4.07 (m, 4H), 2.95 (d, J ) 22.0 Hz, 2H), 2.31 (s, 6H),
1.27 (t, J ) 7.2 Hz, 6H). 13C NMR (CDCl3) δ 172.9, 138.3 (d, J
) 8.7 Hz), 131.6 (d, J ) 5.1 Hz), 130.5 (d, J ) 7.4 Hz), 129.4 (d,
J ) 2.3 Hz), 129.1 (d, J ) 3.0 Hz), 128.3 (d, J ) 3.0 Hz), 62.1 (d,
J ) 6.7 Hz), 28.7 (d, J ) 140.3 Hz), 26.9, 16.2 (d, J ) 5.8 Hz).
General Procedure for 11a-c. Concentrated H2SO4 (3 mL) was
added to a stirring solution of 10a-c (9.7 mmol) in EtOH (60 mL).
The solution was heated to reflux for 18 h. Reaction progress was
monitored by TLC (5% MeOH in CHCl3). The solution was diluted
with water (100 mL), washed with EtOAc (30 mL), and the aqueous
phase was brought to pH 9 with saturated NaHCO3 solution. The
product was extracted with EtOAc (3 × 30 mL), the combined
organic layers were dried over MgSO4, and solvent was removed
in vacuo.
General Procedure for 5e-f. 7a-b (0.66 mmol) was dissolved
in THF (3 mL), and the solution was cooled to 0 °C. One M NaOH
(1 mL, 10 equiv) was then added, and the solution was stirred and
warmed to room temperature. Reaction progress was monitored by
TLC (1:1 EtOAc:hexanes). When starting material had completely
reacted, saturated NaHCO3 (30 mL) was added and the solution
was washed with EtOAc. The aqueous phase was acidified to pH
3 with 1 M HCl, and product was extracted with EtOAc, dried
over MgSO4, and evaporated in vacuo.
2-(Pentylsulfonamidomethyl)benzoic Acid 5e. mp ) 100 °C.
1H NMR (DMSO-d6) δ 13.0 (s, 1H), 7.87 (d, J ) 8.1 Hz, 1H),
7.60 (m, 2H), 7.39 (m, 2H), 4.51 (d, J ) 6.3 Hz, 2H), 2.92 (t, J )
7.8 Hz, 2H), 1.61 (m, 2H), 1.25 (m, 4H), 0.84 (t, J ) 6.9 Hz, 3H).
13C NMR (MeOD) δ 170.3, 140.8, 133.6, 132.3, 131.3, 130.7,
128.8, 53.6, 46.5, 31.3, 24.3, 23.1, 14.0. HRMS (FAB) calcd for
C13H20NO4S [M + H]+, 286.11131; found, 286.11103. Anal.
(C13H19NO4S) C, H, N.
2-(Nonylsulfonamidomethyl)benzoic Acid 5f. mp ) 79-82 °C.
1H NMR (CDCl3) δ 8.04 (d, J ) 7.2 Hz, 1H), 7.60 (m, 2H), 7.43
(t, J ) 6.8 Hz, 1H), 4.60 (s, 2H), 2.89 (t, J ) 8.0 Hz, 2H), 1.66
(m, 2H), 1.28 (m, 12H), 0.92 (t, J ) 7.2 Hz, 3H). 13C NMR
(DMSO-d6) δ 168.3, 139.7, 132.1, 130.4, 129.8, 129.0, 127.2, 51.7,
44.1, 31.3, 28.7, 28.6, 28.5, 27.6, 23.1, 22.1, 14.0. HRMS (FAB)
calcd for C17H28NO4S [M + H]+, 342.17391; found, 342.17478.
Anal. (C17H27NO4S) C, H, N.
Diethyl 4-Aminobenzylphosphonate 11a. 1H NMR (CDCl3) δ
6.91 (dd, J ) 8.0, 2.4 Hz, 2H), 6.47 (d, J ) 8.0 Hz, 2H), 3.86 (m,
4H), 3.73 (br s, 2H), 2.90 (d, J ) 21.2 Hz, 2H), 1.10 (t, J ) 7.2
Hz, 6H). 13C NMR (CDCl3) δ 145.3 (d, J ) 3.6 Hz), 129.9 (d, J
) 6.5 Hz), 119.7 (d, J ) 9.4 Hz), 114.6 (d, J ) 2.9 Hz), 61.5 (d,
J ) 6.6 Hz), 32.1 (d, J ) 138.1 Hz), 15.8 (d, J ) 5.9 Hz).
Diethyl 3-Aminobenzylphosphonate 11b. 1H NMR (CDCl3) δ
7.04 (t, J ) 8.0 Hz, 1H), 6.64 (m, 2H), 6.53 (d, J ) 7.2 Hz, 1H),
3.98 (m, 4H), 3.68 (br s, 2H), 3.03 (d, J ) 21.6 Hz, 2H), 1.22 (t,
J ) 7.2 Hz, 6H). 13C NMR (CDCl3) δ 146.5 (d, J ) 2.9 Hz), 132.3
(d, J ) 8.8 Hz), 129.2 (d, J ) 3.0 Hz), 119.8 (d, J ) 6.6 Hz),
116.3 (d, J ) 6.6 Hz), 113.6 (d, J ) 3.6 Hz), 62.0 (d, J ) 6.6 Hz),
33.5 (d, J ) 137.0 Hz), 16.2 (d, J ) 5.8 Hz).
Diethyl 2-Aminobenzylphosphonate 11c. 1H NMR (CDCl3) δ
7.03 (m, 2H), 6.73 (m, 2H), 4.30 (br s, 2H), 4.03 (m, 4H), 3.12 (d,
J ) 21.2 Hz, 2H), 1.24 (t, J ) 7.2 Hz, 6H). 13C NMR (CDCl3) δ
145.9 (d, J ) 4.6 Hz), 131.4 (d, J ) 6.5 Hz), 128.1 (d, J ) 3.6
Hz), 118.9 (d, J ) 2.9 Hz), 117.1 (d, J ) 9.7 Hz), 117.0 (d, J )
3.5 Hz), 62.3 (d, J ) 6.6 Hz), 30.5 (d, J ) 137.9 Hz), 16.2 (d, J
) 6.0 Hz).
General Procedure for 9a-c. 8a-c (31.3 mmol) was dissolved
in CH3CN (150 mL), and NBS (31.3 mmol) was added. The
solution was then heated to reflux with a 275 W Sunlamp. Reaction
progress was monitored by TLC (30% EtOAc in hexanes). The
solution was then cooled, evaporated in vacuo, and the mixture
was purified by flash chromatography (30% EtOAc in hexanes).
General Procedure for 12a-d. Sulfonyl chloride (4.9 mmol)
was added dropwise to a solution of 11a-b (3.3 mmol) in CH3CN
(13 mL) at 0 °C. Et3N (3.63 mmol) was added dropwise, and the
solution was stirred and allowed to warm to room temperature.
Reaction progress was monitored by TLC (10% MeOH in CHCl3).
When complete (about 2 h), the reaction was quenched by adding
saturated sodium bicarbonate solution. The product was extracted
with EtOAc (3 × 10 mL), and the combined organic extracts were
dried over MgSO4 and concentrated in vacuo. Flash chromatography
(2% MeOH in CHCl3) afforded the product.
1
N,N-(4-Bromophenyl)diacetylaniline 9a. H NMR (CDCl3) δ
7.47 (d, J ) 8.4 Hz, 2H), 7.11 (d, J ) 8.4 Hz, 2H), 4.48 (s, 2H),
2.27 (s, 6H). 13C NMR (CDCl3) δ 172.6, 139.1, 138.4, 130.3, 128.9,
32.0, 26.7.
1
N,N-(3-Bromophenyl)diacetylaniline 9b. H NMR (CDCl3) δ
7.44 (m, 2H), 7.20 (s, 1H), 7.08 (m, 1H), 4.48 (s, 2H), 2.28 (s,
6H). 13C NMR (CDCl3) δ 172.7, 139.7, 139.7, 130.1, 129.3, 128.6,
32.0, 26.8.
1
N,N-(2-Bromophenyl)diacetylaniline 9c. H NMR (CDCl3) δ
7.56 (d, J ) 6.8 Hz, 1H), 7.44 (m, 2H), 7.12 (d, J ) 6.8 Hz, 1H),
4.32 (s, 2H), 2.36 (s, 6H). 13C NMR (CDCl3) δ 172.5, 137.9, 135.0,
131.5, 129.9, 129.5, 129.4, 28.4, 26.7.
Diethyl 4-(Pentylsulfonamido)benzylphosphonate 12a. 1H
NMR (CDCl3) δ 8.42 (br s, 1H), 7.15 (m, 4H), 4.01 (m, 4H), 3.08
(d, J ) 21.2 Hz, 2H), 2.98 (t, J ) 8.0 Hz, 2H), 1.76 (m, 2H), 1.28
(m, 4H), 1.25 (t, J ) 6.8 Hz, 6H), 0.82 (t, J ) 7.2 Hz, 3H). 13C
NMR (CDCl3) δ 136.5 (d, J ) 3.6 Hz), 130.5 (d, 6.6 Hz), 127.2
General Procedure for 10a-c. 9a-c (22.2 mmol) was dissolved
in P(OEt)3 (25 mL, 6.6 equiv), and the solution was heated to reflux

Synthesis and ActiVity of GPAT Inhibitors
Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10 3323
(d, J ) 9.7 Hz), 120.4 (d, J ) 3.3 Hz), 62.2 (d, J ) 6.7 Hz), 51.1,
32.6 (d, J ) 138.1 Hz), 30.1, 22.8, 21.9, 16.1 (d, J ) 5.8 Hz),
13.5.
13C NMR (MeOD) δ 137.9 (d, J ) 3.7 Hz), 131.8 (d, J ) 6.3 Hz),
130.6 (d, J ) 9.6 Hz), 121.4 (d, J ) 2.9 Hz), 51.8, 35.1 (d, J )
134.6 Hz), 31.2, 24.2, 23.1, 14.0. HRMS (FAB) calcd for
C12H20NO5PS [M]+, 321.07998; found, 321.07934. Anal.
(C12H20NO5PS·0.6(H2O)) C, H, N.
4-(Nonylsulfonamido)benzylphosphonic Acid 13b. mp )
201-203 °C. 1H NMR (MeOD) δ 7.29 (dd, J ) 8.6, 2.4 Hz, 2H),
7.20 (d, J ) 8.6 Hz, 2H), 3.09 (d, J ) 21.2, 2H), 3.05 (t, J ) 8.0
Hz, 2H), 1.77 (m, 2H), 1.29 (m, 12H), 0.91 (t, J ) 7.2 Hz, 3H).
13C NMR (MeOD) δ 137.9 (d, J ) 3.3 Hz), 131.8 (d, J ) 6.5 Hz),
130.6 (d, J ) 9.3 Hz), 121.4 (d, J ) 3.0 Hz), 51.8, 35.1 (d, J )
134.5 Hz), 32.9, 30.3, 30.2, 30.1, 29.1, 24.5, 14.4. HRMS (FAB)
calcd for C16H29NO5PS [M + H]+, 378.15041; found, 378.14945.
Anal. (C16H28NO5PS) C, H, N.
Diethyl 4-(Nonylsulfonamido)benzylphosphonate 12b. 1H
NMR (CDCl3) δ 8.61 (br s, 1H), 7.12 (m, 4H), 3.99 (m, 4H), 3.06
(d, J ) 21.2 Hz, 2H), 2.96 (t, J ) 8.0 Hz, 2H), 1.71 (m, 2H), 1.27
(m, 12H), 1.18 (t, J ) 7.2 Hz, 6H), 0.79 (t, J ) 7.2 Hz, 3H). 13C
NMR (CDCl3) δ 136.5 (d, J ) 3.0 Hz), 130.4 (d, J ) 6.7 Hz),
127.0 (d, J ) 9.1 Hz), 120.2 (d, J ) 2.9 Hz), 62.1 (d, J ) 7.0 Hz),
51.0, 32.5 (d, J ) 137.8 Hz), 31.5, 28.9, 28.8, 28.7, 27.9, 23.0,
22.3, 16.0 (d, J ) 5.9 Hz), 13.7.
Diethyl 3-(Pentylsulfonamido)benzylphosphonate 12c. 1H
NMR (CDCl3) δ 8.27 (br s, 1H), 7.19 (m, 3H), 7.01 (d, J ) 6.8
Hz, 1H), 4.00 (m, 4H), 3.11 (d, J ) 21.6, 2H), 3.02 (t, J ) 8.0 Hz,
2H), 1.76 (m, 2H), 1.30 (m, 4H), 1.23 (t, J ) 7.2 Hz, 6H), 0.81, (t,
J ) 7.2 Hz, 3H). 13C NMR (CDCl3) δ 137.8 (d, J ) 2.9 Hz), 132.8
(d, J ) 9.2 Hz), 129.3 (d, J ) 2.9 Hz), 125.7 (d, J ) 6.6 Hz),
121.2 (d, J ) 6.6 Hz), 118.4 (d, J ) 3.5 Hz), 62.2 (d, J ) 6.7 Hz),
51.2, 33.3 (d, J ) 137.3 Hz), 30.1, 22.8, 21.9, 16.1 (d, J ) 5.9
Hz), 13.5.
3-(Pentylsulfonamido)benzylphosphonic Acid 13c. mp )
1
127-128 °C. H NMR (MeOD) δ 7.27 (t, J ) 8.0 Hz, 1H), 7.22
(s, 1H), 7.11 (m, 2H), 3.11 (d, J ) 21.6 Hz, 2H), 3.09 (t, J ) 7.8
Hz, 2H), 1.78 (m, 2H), 1.38 (m, 4H), 0.91 (t, J ) 6.4 Hz, 3H). 13
C
NMR (MeOD) δ 139.5 (d, J ) 3.3 Hz), 136.0 (d, J ) 9.3 Hz),
130.3 (d, J ) 3.4 Hz), 126.8 (d, J ) 5.9 Hz), 122.5 (d, J ) 6.5
Hz), 119.3 (d, J ) 3.4 Hz), 51.9, 35.8 (d, J ) 134.2 Hz), 31.2,
24.2, 23.1, 14.0. HRMS (FAB) calcd for C12H21NO5PS [M + H]+,
322.08781; found, 322.08830. Anal. (C12H20NO5PS) C, H, N.
3-(Nonylsulfonamido)benzylphosphonic Acid 13d. mp )
Diethyl 3-(Nonylsulfonamido)benzylphosphonate 12d. 1H
NMR (CDCl3) δ 8.17 (br s, 1H), 7.20 (m, 3H), 7.02 (d, J ) 7.2
Hz, 1H), 3.99 (m, 4H), 3.12 (d, J ) 21.6 Hz, 2H), 3.03 (t, J ) 8.0
Hz, 2H), 1.76 (m, 2H), 1.31 (m, 12H), 1.26 (t, J ) 6.0 Hz, 6H),
0.83 (t, J ) 7.2 Hz, 3H). 13C NMR (CDCl3) δ 137.8 (d, J ) 3.6
Hz), 132.8 (d, J ) 9.0 Hz), 129.4 (d, J ) 2.9 Hz), 125.7 (d, J )
6.7 Hz), 121.3 (d, 6.5 Hz), 118.5 (d, J ) 3.6 Hz), 62.3 (d, 6.9 Hz),
51.3, 33.3 (d, J ) 137.4 Hz), 31.6, 29.1, 29.0, 28.9, 28.0, 23.2,
22.4, 16.2 (d, J ) 5.9 Hz), 13.9.
General Procedure for 12e-f. 11c (1.36 mmol) was dissolved
in CH3CN (3.3 mL) and then pyridine (10.8 mmol) was added.
The solution was cooled to 0 °C, and sulfonyl chloride (1.63 mmol)
was added slowly by syringe. The solution was allowed to warm
to room temperature. Reaction progress was monitored by TLC
(5% MeOH in CHCl3). When complete, the reaction was quenched
by adding saturated NaHCO3 solution. The product was extracted
with EtOAc (3 × 5 mL), washed with 1 N HCl, and the combined
organic extracts were dried over MgSO4 and concentrated in vacuo.
The product was purified by flash chromatography (2% MeOH in
CHCl3).
1
149-150 °C. H NMR (MeOD) δ 7.27 (t, J ) 8.0 Hz, 1H), 7.22
(s, 1H), 7.11 (m, 2H), 3.11 (d, J ) 21.6 Hz, 2H), 3.08 (t, J ) 7.6
Hz, 2H), 1.77 (m, 2H), 1.33 (m, 12H), 0.91 (t, J ) 6.4 Hz, 3H).
13C NMR (MeOD) δ 139.5 (d, J ) 3.0 Hz), 130.3 (d, J ) 3.0 Hz),
126.8 (d, J ) 6.1 Hz), 122.5, (d, J ) 6.3 Hz), 119.3 (d, J ) 3.5
Hz), 51.9, 35.8 (d, J ) 134.0 Hz), 32.9, 30.3, 30.2, 30.1, 29.1,
24.5, 23.6, 14.3. HRMS (FAB) calcd for C16H29NO5PS [M + H]+,
378.15041; found, 378.14975. Anal. (C16H28NO5PS) C, H, N.
1
2-(Pentylsulfonamido)benzylphosphonic Acid 13e. H NMR
(DMSO-d6) δ 9.73 (s, 1H), 7.38 (d, J ) 8.0 Hz, 1H), 7.25 (m,
2H), 7.13 (t, J ) 7.6 Hz, 1H), 3.14 (t, J ) 8.0 Hz, 2H), 3.10 (d, J
) 20.8 Hz, 2H), 1.71 (m, 2H), 1.32 (m, 4H), 0.85 (t, J ) 7.2 Hz,
3H). 13C NMR (DMSO-d6) δ 136.2 (d, J ) 5.8 Hz), 131.6 (d, J )
6.4 Hz), 127.6 (d, J ) 10.0 Hz), 127.1 (d, J ) 3.4 Hz), 125.0 (d,
J ) 2.8 Hz), 123.7 (d, J ) 3.0 Hz), 52.3, 32.5 (d, J ) 130.3 Hz),
29.4, 22.7, 21.3, 13.3. HRMS (FAB) calcd for C12H20NO5PS [M
+ H]+, 322.08781; found, 322.08660. Anal. (C12H20NO5PS·1/
4(H2O)) C, H, N.
Diethyl 2-(Pentylsulfonamido)benzylphosphonate 12e. 1H
NMR (CDCl3) δ 8.71 (s, 1H), 7.40 (d, J ) 7.6 Hz), 7.22 (m, 1H),
7.12 (m, 2H), 3.97 (m, 4H), 3.21 (d, J ) 21.2 Hz, 2H), 3.11 (t, J
) 8.0 Hz, 2H), 1.86 (m, 2H), 1.37 (m, 4H), 1.19 (t, J ) 7.2 Hz,
6H), 0.85 (t, J ) 7.2 Hz, 3H). 13C NMR (CDCl3) δ 136.2 (d, J )
5.2 Hz), 131.5 (d, J ) 7.2 Hz), 128.2 (d, J ) 3.7 Hz), 125.8 (d, J
) 2.9 Hz), 125.5 (d, J ) 9.7 Hz), 124.6 (d, J ) 3.5 Hz), 62.6 (d,
J ) 6.9 Hz), 53.4, 30.9 (d, J ) 136.6 Hz), 30.1, 23.0, 21.9, 16.0
(d, J ) 5.9 Hz), 13.5.
2-(Nonylsulfonamido)benzylphosphonic Acid 13f. mp )
1
104-106 °C. H NMR (DMSO-d6) δ 9.80 (s, 1H), 7.37 (d, J )
8.0 Hz, 1H), 7.25 (m, 2H), 7.15 (t, J ) 7.6 Hz, 1H), 3.14 (t, J )
7.6 Hz, 2H), 3.09 (d, J ) 21.2 Hz, 2H), 1.68 (m, 2H), 1.35 (m,
2H), 1.22 (m, 8H), 0.85 (t, J ) 6.8 Hz). 13C NMR (DMSO-d6) δ
136.3 (d, J ) 5.7 Hz), 131.8 (d, J ) 6.5 Hz), 127.7 (d, J ) 8.7
Hz), 127.3 (d, J ) 3.3 Hz), 125.2 (d, J ) 2.6 Hz), 123.8 (d, J )
3.0 Hz), 52.3, 32.6 (d, J ) 130.5 Hz), 31.2, 28.6, 28.5, 28.4, 27.4,
23.2, 22.0, 13.9. HRMS (FAB) calcd for C16H28NO5PS [M + H]+,
378.15041; found, 378.15020. Anal. (C16H28NO5PS) C, H, N.
General Procedure for 14a-i. To a stirring solution of the
aniline starting material (3.3 mmol) in CH2Cl2 (12 mL) at 0 °C
was added pyridine (7.5 equiv). The sulfonyl chloride (1.2 equiv)
was then added slowly via syringe. The solution was stirred and
allowed to warm to room temperature. Reaction progress was
monitored by TLC (20% EtOAc in hexanes). When complete, the
reaction was poured into saturated NaHCO3 solution (45 mL),
extracted with CH2Cl2 (3 × 15 mL), and washed with 1 M HCl
(50 mL). The combined organic phases were concentrated in vacuo,
and recrystallization from EtOAc/hexanes afforded 14a-i.
Methyl 4-(Nonylsulfonamido)benzoate 14a. 1H NMR (DMSO-
d6) δ 10.33 (s, 1H), 7.90 (d, J ) 8.4 Hz, 2H), 7.29 (d, J ) 8.4 Hz,
2H), 3.80 (s, 3H), 3.17 (t, J ) 8.0 Hz, 2H), 1.63 (m, 2H), 1.15 (m,
12H), 0.81 (t, J ) 6.8 Hz, 3H). 13C NMR (DMSO-d6) δ 165.7,
143.1, 130.7, 123.8, 117.4, 51.8, 50.8, 31.1, 28.5, 28.5, 28.2, 27.0,
22.9, 22.0, 13.8.
Diethyl 2-(Nonylsulfonamido)benzylphosphonate 12f. 1H NMR
(CDCl3) δ 8.71 (s, 1H), 7.44 (d, J ) 8.0 Hz, 1H), 7.28 (m, 1H),
7.17 (m, 2H), 4.01 (m, 4H), 3.25 (d, J ) 21.2 Hz, 2H), 3.17 (t, J
) 8.0 Hz, 2H), 1.91 (m, 2H), 1.40 (m, 2H), 1.25 (m, 16H), 0.89 (t,
J ) 7.2 Hz). 13C NMR (CDCl3) δ 136.4 (d, J ) 5.0 Hz), 131.7 (d,
J ) 6.7 Hz), 128.5 (d, J ) 3.7 Hz), 126.0 (d, J ) 2.8 Hz), 125.7
(d, J ) 10.1 Hz), 124.9 (d, J ) 3.1 Hz), 62.8 (d, J ) 6.7 Hz), 53.8,
31.7, 31.2 (d, J ) 136.4 Hz), 29.1, 29.1, 29.0, 28.2, 23.5, 22.5,
16.2 (d, J ) 5.8 Hz), 14.0.
General Procedure for 13a-f. TMSBr (8.6 mmol) was added
to a solution of 12a-f (0.277 mmol) in CH2Cl2 (2 mL), and the
solution was stirred at room temperature. After 24 h, the reaction
was quenched by adding MeOH (3 × 1.6 mL). The solution was
concentrated in vacuo and dissolved in saturated NaHCO3 solution
(10 mL). This solution was washed with Et2O (5 mL) and then
acidified with 1 N HCl. The product was extracted with Et2O (3 ×
5 mL), and the combined organic extracts were dried over MgSO4
and dried in vacuo.
4-(Pentylsulfonamido)benzylphosphonic Acid 13a. mp )
198-200 °C. 1H NMR (MeOD) δ 7.29 (dd, J ) 8.4, 2.4 Hz, 2H),
7.20 (d, J ) 8.4 Hz, 2H), 3.10 (d, J ) 21.6 Hz, 2H), 3.05 (t, J )
8.0 Hz, 2H), 1.78 (m, 2H), 1.34 (m, 4H), 0.90 (t, J ) 7.2 Hz, 3H).
Methyl 4-(Phenylsulfonamido)benzoate 14b. 1H NMR (CDCl3)
δ 7.91 (d, J ) 8.4 Hz, 2H), 7.85 (d, J ) 8.4 Hz, 2H), 7.56 (t, J )
7.2 Hz, 1H), 7.46 (t, J ) 8.0 Hz, 2H), 7.16 (d, J ) 8.4 Hz, 2H),

3324 Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10
Wydysh et al.
3.87 (s, 3H). 13C NMR (DMSO-d6) δ 165.6, 142.3, 139.2, 133.2,
130.5, 129.3, 126.6, 124.4, 118.2, 51.8.
1H), 7.64 (m, 1H), 7.44 (m, 2H), 3.07 (t, J ) 7.6 Hz, 2H), 1.65
(m, 2H), 1.21 (m, 12H), 0.83 (t, J ) 7.2 Hz, 3H). 13C NMR
(DMSO-d6) δ 166.8, 138.7, 131.8, 129.5, 124.3, 123.2, 119.7, 50.5,
31.1, 28.5, 28.5, 28.3, 27.1, 22.9, 22.0, 13.8. HRMS (FAB) calcd
for C16H26NO4S [M + H]+, 328.15826; found, 328.15640. Anal.
(C16H25NO4S) C, H, N.
3-(Phenylsulfonamido)benzoic Acid 15e. mp ) 203-204 °C.
1H NMR (DMSO-d6) δ 13.02 (br s, 1H), 10.51 (br s, 1H), 7.75 (d,
J ) 7.2 Hz, 2H), 7.68 (s, 1H), 7.56 (m, 4H), 7.34 (m, 2H). 13C
NMR (DMSO-d6) δ 166.6, 139.2, 137.9, 133.0, 131.7, 129.4, 129.3,
126.5, 124.8, 124.0, 120.5. HRMS (FAB) calcd for C13H11NO4S
[M]+, 277.04088; found, 277.04054. Anal. (C13H11NO4S·1/4(H2O))
C, H, N.
Methyl 4-(4-Chlorophenylsulfonamido)benzoate 14c. 1H NMR
(DMSO-d6) δ 10.94 (s, 1H), 7.83 (m, 4H), 7.63 (d, J ) 8.0 Hz,
2H), 7.23 (d, J ) 8.0 Hz, 2H), 3.77 (s, 3H). 13C NMR (DMSO-d6)
δ 165.5, 141.9, 138.1, 138.0, 130.6, 129.5, 128.5, 124.7, 118.4,
51.8.
Methyl 3-(Nonylsulfonamido)benzoate 14d. 1H NMR (DMSO-
d6) δ 10.05 (s, 1H), 7.83 (s, 1H), 7.65 (d, J ) 6.8 Hz, 1H), 7.46
(m, 2H), 3.84 (s, 3H), 3.08 (t, J ) 8.0 Hz, 2H), 1.63 (m, 2H), 1.63
(m, 2H), 1.15 (m, 12H), 0.81 (t, J ) 6.8 Hz, 3H). 13C NMR
(DMSO-d6) δ 165.7, 138.9, 130.6, 129.7, 124.1, 123.6, 119.4, 52.1,
50.6, 31.1, 28.5, 28.5, 28.3, 27.1, 22.9, 22.0, 13.8.
Methyl 3-(Phenylsulfonamido)benzoate 14e. 1H NMR (DMSO-
d6) δ 10.57 (s, 1H), 7.78 (d, J ) 8.0 Hz, 2H), 7.74 (s, 1H), 7.54
(m, 4H), 7.38 (m, 2H), 3.79 (s, 3H). 13C NMR (DMSO-d6) δ 165.6,
139.2, 138.1, 133.0, 130.5, 129.6, 129.3, 126.6, 124.6, 124.4, 120.3,
52.2.
3-(4-Chlorophenylsulfonamido)benzoic Acid 15f. mp )
1
242-243 °C. H NMR (MeOD) δ 7.76 (d, J ) 8.8 Hz, 4H), 7.52
(d, J ) 8.4 Hz, 2H), 7.34 (m, 2H). 13C NMR (MeOD) δ 168.9,
140.2, 139.5, 139.0, 133.0, 130.3, 130.3, 129.8, 127.0, 126.4, 123.1.
HRMS (FAB) calcd for C13H10ClNO4S [M]+, 311.00191; found,
311.00152. Anal. (C13H10ClNO4S) C, H, N.
Methyl 3-(4-Chlorophenylsulfonamido)benzoate 14f. 1H NMR
(DMSO-d6) δ 10.63 (s, 1H), 7.74 (m, 3H), 7.61 (m, 3H), 7.39 (m,
2H), 3.80 (s, 3H). 13C NMR (DMSO-d6) δ 165.5, 138.0, 138.0,
137.8, 130.6, 129.8, 129.5, 128.5, 124.9, 124.6, 120.5, 52.2.
Methyl 2-(Nonylsulfonamido)benzoate 14g. 1H NMR (DMSO-
d6) δ 10.15 (s, 1H), 7.96 (d, J ) 8.0 Hz, 1H), 7.62 (m, 2H), 7.20
(t, J ) 7.6 Hz, 1H), 3.88 (s, 3H), 3.27 (t, J ) 8.0 Hz, 2H), 1.62
(m, 2H), 1.16 (m, 12H), 0.83 (t, J ) 7.2 Hz, 3H). 13C NMR
(DMSO-d6) δ 167.8, 139.8, 134.7, 131.0, 123.0, 118.5, 116.1, 52.6,
51.2, 31.1, 28.4, 28.4, 28.2, 27.0, 22.8, 21.9, 13.8.
2-(Nonylsulfonamido)benzoic Acid 15g. mp ) 122-124 °C.
1H NMR (MeOD) δ 8.11 (d, J ) 8.0 Hz, 1H), 7.73 (d, J ) 8.4 Hz,
1H), 7.59 (t, J ) 7.6 Hz, 1H), 7.16 (t, J ) 7.6 Hz, 1H), 3.18 (t, J
) 8.0 Hz, 2H), 1.71 (m, 2H), 1.24 (m, 12H), 0.88 (t, J ) 7.2 Hz,
3H). 13C NMR (MeOD) δ 171.3, 142.4, 135.7, 133.1, 123.8, 118.8,
117.0, 52.3, 32.9, 30.2, 30.1, 29.9, 28.8, 24.4, 23.6, 14.4. HRMS
(FAB) calcd for C16H25NO4S [M]+, 327.15043; found, 327.15044.
Anal. (C16H25NO4S) C, H, N.
2-(Phenylsulfonamido)benzoic Acid 15h. mp ) 213-215 °C.
1H NMR (MeOD) δ 7.95 (d, J ) 8.0 Hz, 1H), 7.81 (d, J ) 8.0 Hz,
2H), 7.69 (d, J ) 8.4 Hz, 1H), 7.56 (t, J ) 7.6 Hz, 1H), 7.49 (m,
3H), 7.09 (t, J ) 7.6 Hz, 1H). 13C NMR (DMSO-d6) δ 169.7, 139.7,
138.5, 134.4, 133.5, 131.5, 129.4, 126.8, 123.3, 118.4, 116.7. HRMS
(FAB) calcd for C13H11NO4S [M]+, 277.04088; found, 277.04124.
Anal. (C13H11NO4S·1/4(H2O)) C, H, N.
2-(4-Chlorophenylsulfonamido)benzoic Acid 15i. mp )
202-203 °C. 1H NMR (DMSO-d6) δ 13.98 (br s, 1H), 11.12 (br s,
1H), 7.90 (d, J ) 8.0 Hz, 1H), 7.81 (d, J ) 8.8 Hz, 2H), 7.63 (d,
J ) 8.8 Hz, 2H), 7.54 (t, J ) 7.6 Hz, 1H), 7.48 (d, J ) 8.4 Hz,
1H), 7.14 (t, J ) 7.2 Hz, 1H). 13C NMR (MeOD) δ 171.1, 141.3,
140.6, 139.0, 135.4, 132.8, 130.3, 129.9, 124.7, 120.6, 118.3. HRMS
(FAB) calcd for C13H10ClNO4S [M]+, 311.00191; found, 311.00136.
Anal. (C13H10ClNO4S) C, H, N.
Methyl 2-(Phenylsulfonamido)benzoate 14h. 1H NMR (CDCl3)
δ 10.67 (s, 1H), 7.87 (d, J ) 8.0 Hz, 1H), 7.82 (d, J ) 8.0 Hz,
2H), 7.67 (d, J ) 8.4 Hz, 1H), 7.40 (m, 4H), 7.00 (t, J ) 7.6 Hz,
1H), 3.82 (s, 3H). 13C NMR (CDCl3) δ 168.1, 140.0, 139.0, 134.3,
132.9, 131.0, 128.8, 126.9, 122.9, 118.9, 115.7, 52.3.
Methyl 2-(4-Chlorophenylsulfonamido)benzoate 14i. 1H NMR
(DMSO-d6) δ 10.41 (s, 1H), 7.83 (d, J ) 8.0 Hz, 1H), 7.77 (d, J
) 8.8 Hz, 2H), 7.63 (d, J ) 8.8 Hz, 2H), 7.57 (t, J ) 8.0 Hz, 1H),
7.43 (d, J ) 8.4 Hz, 1H), 7.21 (t, J ) 8.0 Hz, 1H), 3.79 (s, 3H).
13C NMR (DMSO-d6) δ 167.3, 138.3, 138.0, 137.5, 134.2, 130.9,
129.4, 128.8, 124.2, 120.5, 118.6, 52.5.
General Procedure for 15a-i. To a stirring suspension of
potassium t-butoxide (5.88 mmol) in Et2O (15 mL) cooled to 0
°C, was added water (1.4 mmol) via syringe. The slurry was stirred
for 5 min, and 14a-i (0.67 mmol) was added. The mixture was
stirred at room temperature until starting material disappeared by
TLC analysis (20% EtOAc in hexanes). Ice water was added until
two clear layers formed. The aqueous layer was separated and
acidified with 1 M HCl. The product was then extracted with Et2O
(3 × 20 mL) and evaporated in vacuo to afford 15a-i.
4-(Nonylsulfonamido)benzoic Acid 15a. mp ) 193-194 °C.
1H NMR (MeOD) δ 7.99 (d, J ) 8.2 Hz, 2H), 7.31 (d, J ) 8.2 Hz,
2H), 3.17 (t, J ) 8.0 Hz, 2H), 1.78 (m, 2H), 1.40 (m, 2H), 1.28
(m, 10H), 0.89 (t, J ) 7.2 Hz, 3H). 13C NMR (MeOD) δ 169.3,
144.3, 132.3, 126.7, 118.8, 52.4, 32.9, 30.2, 30.2, 30.0, 28.9, 24.4,
23.6, 14.3. HRMS (FAB) calcd for C16H25NO4S [M]+, 327.15043;
found, 327.14957. Anal. (C16H25NO4S·1/4(H2O)) C, H, N.
4-(Phenylsulfonamido)benzoic Acid 15b. mp ) 186-188 °C.
1H NMR (DMSO-d6) δ 12.72 (br s, 1H), 10.82 (br s, 1H), 7.80 (m,
4H), 7.61 (t, J ) 6.8 Hz, 1H), 7.56 (t, J ) 8.0 Hz, 2H), 7.20 (t, J
) 7.2 Hz, 2H). 13C NMR (DMSO-d6) δ 166.6, 141.9, 142.0, 133.2,
130.7, 129.4, 126.6, 125.6, 118.2. HRMS (FAB) calcd for
C13H11NO4S [M]+, 277.04088; found, 277.04077. Anal.
(C13H11NO4S) C, H, N.
General Procedure for 16a-f. To a stirring solution of the
aniline starting material (3.3 mmol) in CH2Cl2 (12 mL) at 0 °C
was added pyridine (7.5 equiv). Then sulfonyl chloride (1.2 equiv)
was then added slowly via syringe. The solution was stirred and
allowed to warm to room temperature. Reaction progress was
monitored by TLC (20% EtOAc in hexanes). When complete, the
reaction was poured into saturated NaHCO3 (45 mL), extracted with
CH2Cl2 (3 × 15 mL), and washed with 1 M HCl (50 mL). The
combined organic phases were concentrated in vacuo, and the
resulting solid was recrystallized from EtOAc/hexanes to afford
16a-f.
Methyl 4-(Phenylmethylsulfonamido)benzoate 16a. 1H NMR
(DMSO-d6) δ 10.37 (s, 1H), 7.90 (d, J ) 8.0 Hz, 2H), 7.33 (m,
3H), 7.24 (m, 4H), 4.58 (s, 2H), 3.82 (s, 3H). 13C NMR (DMSO-
d6) δ 165.7, 143.1, 130.9, 130.6, 129.2, 128.4, 128.3, 123.6, 117.2,
57.2, 51.8.
Methyl 4-(2-Phenylethylsulfonamido)benzoate 16b. 1H NMR
(CDCl3) δ 7.97 (d, J ) 7.4 Hz, 2H), 7.29 (m, 3H), 7.13 (d, J ) 7.4
Hz, 2H), 7.06 (d, J ) 6.8 Hz, 2H), 6.68 (s, 1H), 3.91 (s, 3H), 3.43
(t, J ) 8.0 Hz, 2H), 3.14 (t, J ) 8.0 Hz, 2H). 13C NMR (CDCl3)
δ 166.3, 140.9, 137.1, 131.2, 129.0, 128.3, 127.1, 126.1, 118.1,
53.0, 52.1, 29.8.
4-(4-Chlorophenylsulfonamido)benzoic Acid 15c. mp )
254-256 °C. 1H NMR (DMSO-d6) δ 12.76 (br s, 1H), 10.86 (br s,
1H), 7.81 (d, J ) 6.4 Hz, 4H), 7.65 (d, J ) 7.2 Hz, 2H), 7.18 (d,
J ) 6.8 Hz, 2H). 13C NMR (DMSO-d6) δ 166.6, 141.5, 138.1,
138.0, 130.7, 129.5, 128.5, 125.9, 118.4. HRMS (FAB) calcd for
C13H11ClNO4S [M + H]+, 312.00973; found, 312.00859. Anal.
(C13H10ClNO4S·1/4(H2O)) C, H, N.
Methyl 3-(Phenylmethylsulfonamido)benzoate 16c. 1H NMR
(DMSO-d6) δ 10.11 (s, 1H), 7.78 (s, 1H), 7.65 (d, J ) 6.8 Hz,
1H), 7.44 (m, 2H), 7.33 (m, 3H), 7.26 (m, 2H), 4.50 (s, 2H), 3.85
(s, 3H). 13C NMR (DMSO-d6) δ 165.8, 138.9, 130.8, 130.6, 129.6,
129.2, 128.3, 128.2, 123.8, 123.3, 119.1, 57.1, 52.2.
3-(Nonylsulfonamido)benzoic Acid 15d. mp ) 183-184 °C.
Methyl 3-(2-Phenylethylsulfonamido)benzoate 16d. 1H NMR
(CDCl3) δ 7.84 (d, J ) 7.6 Hz, 1H), 7.79 (s, 1H), 7.47 (d, J ) 8.0
1H NMR (DMSO-d6) δ 13.03 (br s, 1H), 9.98 (s, 1H), 7.81 (s,

Synthesis and ActiVity of GPAT Inhibitors
Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10 3325
Hz, 1H), 7.41 (t, J ) 7.6 Hz, 1H), 7.26 (m, 4H), 7.14 (d, J ) 7.6
Hz, 2H), 3.96 (s, 3H), 3.41 (t, J ) 7.6 Hz, 2H), 3.16 (t, J ) 7.6
Hz, 2H). 13C NMR (CDCl3) δ 166.4, 137.3, 137.1, 131.4, 129.7,
128.9, 128.3, 127.0, 126.0, 124.6, 121.2, 52.8, 52.4, 29.7.
Methyl 2-(Phenylmethylsulfonamido)benzoate 16e. 1H NMR
(CDCl3) δ 10.34 (s, 1H), 7.97 (d, J ) 7.6 Hz, 1H), 7.70 (d, J )
8.4 Hz, 1H), 7.46 (t, J ) 7.6 Hz, 1H), 7.25 (m, 3H), 7.14 (d, J )
7.2 Hz, 2H), 7.07 (t, J ) 7.6 Hz, 1H), 4.36 (s, 2H), 3.77 (s, 3H).
13C NMR (CDCl3) δ 167.6, 140.5, 134.4, 131.0, 130.2, 128.3, 128.3,
127.8, 122.4, 117.4, 114.9, 57.7, 52.0.
(0.04 mmol), Et3N (2.94 mmol), and EtOH (8 mL), and the solution
was heated to reflux overnight (16 h). The solution was then diluted
with 30 mL EtOAc, washed with 50 mL saturated NaHCO3
solution, 50 mL H2O, dried over MgSO4, and concentrated in vacuo.
The product was then purified by flash chromatography (EtOAc).
Diethyl 4-Acetamidophenylphosphonate 19a. Characterization
data are in agreement with literature values.36
Diethyl 3-Acetamidophenylphosphonate 19b. 1H NMR
(CDCl3) δ 9.91 (s, 1H), 8.29 (s, 1H), 7.89 (d, J ) 15.0 Hz, 1H),
7.37 (m, 2H), 4.02 (m, 4H), 2.17 (s, 3H), 1.26 (t, J ) 7.2 Hz, 6H).
13C NMR (CDCl3) δ 169.3, 139.5 (d, J ) 18.4 Hz), 129.2, (d, J )
16.1 Hz), 127.5 (d, J ) 185 Hz), 125.7 (d, J ) 8.6 Hz), 123.7 (d,
J ) 3.2 Hz), 122.7 (d, J ) 12.1 Hz), 62.2 (d, J ) 5.3 Hz), 24.0,
16.0 (d, J ) 6.5 Hz).
1
Methyl 2-(2-Phenylethylsulfonamido)benzoate 16f. H NMR
(CDCl3) δ 10.52 (s, 1H), 8.06 (d, J ) 8.0 Hz, 1H), 7.79 (d, J )
8.4 Hz, 1H), 7.56 (t, J ) 8.4 Hz, 1H), 7.25 (m, 3H), 7.11 (m, 3H),
3.95 (s, 3H), 3.45 (t, J ) 8.0 Hz, 2H), 3.14 (t, J ) 8.0 Hz, 2H).
13C NMR (CDCl3) δ 168.1, 140.6, 137.1, 134.7, 131.4, 128.5, 128.0,
126.7, 122.5, 117.5, 114.9, 52.9, 52.3, 29.4.
Diethyl 2-Acetamidophenylphosphonate 19c. Characterization
data are in agreement with literature values.37
General Procedure for 17a-f. To a stirring suspension of
potassium t-butoxide (5.88 mmol) in Et2O (15 mL) cooled to 0 °C
was added water (1.4 mmol) via syringe. The slurry was stirred
for 5 min, and 16a-f (0.67 mmol) was added. The mixture was
stirred at room temperature until starting material disappeared by
TLC analysis (20% EtOAc in hexanes). Ice water was added until
two clear layers formed. The aqueous layer was separated and
acidified with 1 M HCl. The product was then extracted with Et2O
(3 × 20 mL) and evaporated in vacuo to afford 17a-f.
Diethyl 4-(Octylsulfonamido)phenylphosphonate 20a. 1H NMR
(CDCl3) δ 8.87 (s, 1H), 7.72 (dd, J ) 13.2, 7.8 Hz, 2H), 7.37 (dd,
J ) 7.8, 3.6 Hz, 2H), 4.08 (m, 4H), 3.10 (t, J ) 8.0 Hz, 2H), 1.79
(m, 2H), 1.29 (t, J ) 7.2 Hz, 6H), 1.23 (m, 10H), 0.82 (t, J ) 7.2
Hz, 3H). 13C NMR (CDCl3) δ 142.0 (d, J ) 3 Hz), 133.2 (d, J )
10.9 Hz), 122.4 (d, J ) 193 Hz), 118.1 (d, J ) 15.4 Hz), 62.2 (d,
J ) 5.5 Hz), 51.9, 31.5, 28.8, 28.7, 28.0, 23.2, 22.4, 16.1 (d, J )
6.5 Hz), 13.8.
Diethyl 3-(Octylsulfonamido)phenylphosphonate 20b. 1H NMR
(CDCl3) δ 9.53 (s, 1H), 7.89 (d, J ) 15.2 Hz, 1H), 7.67 (s, 1H),
7.38 (m, 2H), 4.11 (m, 4H), 3.04 (t, J ) 8.0 Hz, 2H), 1.77 (m,
2H), 1.28 (t, J ) 7.2 Hz, 6H), 1.17 (m, 10H), 0.80 (t, J ) 6.8 Hz,
3H). 13C NMR (CDCl3) δ 139.0 (d, J ) 9.2 Hz), 129.6 (d, J )
16.2 Hz), 128.9 (d, J ) 189 Hz), 125.9 (d, J ) 8.3 Hz), 123.1 (d,
J ) 12.6 Hz), 122.2 (d, J ) 3.0 Hz), 62.4 (d, J ) 5.8 Hz), 51.5,
31.4, 28.7, 28.7, 28.0, 23.1, 22.3, 16.0 (d, J ) 6.4 Hz), 13.8.
Diethyl 2-(Octylsulfonamido)phenylphosphonate 20c. 1H NMR
(CDCl3) δ 9.94 (s, 1H), 7.73 (t, J ) 8.0 Hz, 1H), 7.59 (m, 1H),
7.53 (m, 1H), 7.14 (dt, J ) 7.2, 2.8 Hz, 1H), 4.09 (m, 4H), 3.14 (t,
J ) 8.0 Hz, 2H), 1.84 (m, 2H), 1.34 (t, J ) 7.2 Hz, 6H), 1.26 (m,
10H), 0.86 (t, J ) 7.2 Hz, 3H). 13C NMR (CDCl3) δ 142.2 (d, J )
7.4 Hz), 134.2 (d, J ) 2.3 Hz), 133.1 (d, J ) 5.9 Hz), 122.9 (d, J
) 13.3 Hz), 118.3 (d, J ) 11.5 Hz), 114.0 (d, J ) 180 Hz), 62.7
(d, J ) 5.2 Hz), 52.2, 31.6, 28.9, 28.8, 28.1, 23.2, 22.4, 16.1 (d, J
) 6.5 Hz), 13.9.
4-(Phenylmethylsulfonamido)benzoic Acid 17a. mp ) 221-223
1
°C. H NMR (DMSO-d6) δ 12.72 (br s, 1H), 10.29 (s, 1H), 7.88
(d, J ) 8.4 Hz, 2H), 7.33 (m, 3H), 7.24 (m, 4H), 4.56 (s, 2H). 13
C
NMR (DMSO-d6) δ 166.8, 142.7, 130.9, 130.8, 129.2, 128.3, 128.3,
124.8, 117.2, 57.1. HRMS (FAB) calcd for C14H14NO4S [M + H]+,
292.06435; found, 292.06397. Anal. (C14H13NO4S) C, H, N.
4-(2-Phenylethylsulfonamido)benzoic Acid 17b. mp ) 222-223
1
°C. H NMR (DMSO-d6) δ 12.74 (br s, 1H), 10.38 (s, 1H), 7.90
(d, J ) 8.0 Hz, 2H), 7.26 (m, 2H), 7.23 (m, 2H), 7.18 (m, 3H),
3.48 (t, J ) 6.4, 2H), 2.98 (t, J ) 6.4 Hz, 2H). 13C NMR (DMSO-
d6) δ 166.8, 142.4, 137.8, 130.8, 128.4, 128.3, 126.5, 125.2, 117.8,
51.9, 29.0. HRMS (FAB) calcd for C15H16NO4S [M + H]+,
306.08000; found, 306.07892. Anal. (C15H15NO4S) C, H, N.
3-(Phenylmethylsulfonamido)benzoic Acid 17c. mp ) 205-206
1
°C. H NMR (DMSO-d6) δ 13.02 (br s, 1H), 10.06 (s, 1H), 7.79
(s, 1H), 7.64 (d, J ) 7.2 Hz, 1H), 7.42 (m, 2H), 7.33 (m, 3H), 7.25
(m, 2H), 4.48 (s, 2H). 13C NMR (DMSO-d6) δ 166.9, 138.7, 131.8,
130.9, 129.4, 129.3, 128.3, 128.2, 124.1, 122.9, 119.4, 57.0. HRMS
(FAB) calcd for C14H14NO4S [M + H]+, 292.06435; found,
292.06448. Anal. (C14H13NO4S) C, H, N.
4-(Octylsulfonamido)phenylphosphonic Acid 21a. mp )
185-187 °C. 1H NMR (MeOD) δ 7.75 (dd, J ) 12.8, 8.0 Hz, 2H),
7.33 (dd, J ) 8.0, 3.2 Hz, 2H), 3.15 (t, J ) 8.0 Hz, 2H), 1.78 (m,
2H), 1.39 (m, 2H), 1.28 (m, 8H), 0.90 (t, J ) 7.2 Hz, 3H). 13C
NMR (MeOD) δ 143.0 (d, J ) 3.6 Hz), 133.4 (d, J ) 11.0 Hz),
127.7 (d, J ) 190 Hz), 119.1 (d, J ) 15.2 Hz), 52.4, 32.8, 30.0,
29.9, 29.0, 24.5, 23.6, 14.3. HRMS (FAB) calcd for C14H25NO5PS
3-(2-Phenylethylsulfonamido)benzoic Acid 17d. mp ) 199-200
1
°C. H NMR (DMSO-d6) δ 13.06 (s, 1H), 10.11 (s, 1H), 7.85 (s,
1H), 7.67 (d, J ) 6.8 Hz, 1H), 7.48 (m, 2H), 7.24 (m, 2H), 7.17
(m, 3H), 3.38 (t, J ) 8.0 Hz, 2H), 2.99 (t, J ) 8.0 Hz, 2H). 13C
NMR (DMSO-d6) δ 166.8, 138.5, 137.9, 131.9, 129.6, 128.4, 128.3,
126.5, 124.6, 123.8, 120.2, 51.7, 29.0. HRMS (FAB) calcd for
C15H16NO4S [M + H]+, 306.08000; found, 306.08051. Anal.
(C15H15NO4S) C, H, N.
[M
+
H]+, 350.11911; found, 350.11869. Anal. (C14H24-
NO5PS·0.6(H2O)) C, H, N.
3-(Octylsulfonamido)phenylphosphonic Acid 21b. mp )
112-114 °C. 1H NMR (MeOD) δ 7.72 (d, J ) 14.8 Hz, 1H), 7.55
(m, 1H), 7.44 (m, 2H), 3.12 (t, J ) 8.0 Hz, 2H), 1.78 (m, 2H),
1.39 (m, 2H), 1.27 (m, 8H), 0.90 (t, J ) 7.2 Hz, 3H). 13C NMR
(MeOD) δ 139.6 (d, J ) 18.2 Hz), 134.5 (d, J ) 184 Hz), 130.5
(d, J ) 16.1 Hz), 127.3 (d, J ) 9.5 Hz), 123.8 (d, J ) 3.0 Hz),
122.8 (d, J ) 11.6 Hz), 52.2, 32.7, 30.0, 29.9, 29.0, 24.4, 23.5,
14.3. HRMS (FAB) calcd for C14H25NO5PS [M + H]+, 350.11911;
found, 350.11879. Anal. (C14H24NO5PS) C, H, N.
2-(Phenylmethylsulfonamido)benzoic Acid 17e. mp ) 216-219
1
°C. H NMR (DMSO-d6) δ 13.86 (br s, 1H), 10.68 (s, 1H), 7.99
(d, J ) 7.6 Hz, 1H), 7.58 (m, 2H), 7.32 (m, 3H), 7.19 (m, 3H),
4.69 (s, 2H). 13C NMR (DMSO-d6) δ 169.6, 140.7, 134.6, 131.5,
130.7, 128.8, 128.4, 128.3, 122.4, 117.2, 115.4, 57.2. HRMS (FAB)
calcd for C14H13NO4S [M]+, 291.05653; found, 291.05655. Anal.
(C14H13NO4S) C, H, N.
2-(Octylsulfonamido)phenylphosphonic Acid 21c. mp ) 92-94
1
2-(2-Phenylethylsulfonamido)benzoic Acid 17f. mp ) 157-159
°C. 1H NMR (DMSO-d6) δ 13.90 (br s, 1H), 10.74 (br s, 1H), 7.98
(d, J ) 8.0 Hz, 1H), 7.61 (d, J ) 4.4 Hz, 2H), 7.20 (m, 2H), 7.16
(m, 4H), 3.61 (t, J ) 8.0 Hz, 2H), 2.98 (t, J ) 8.0 Hz, 2H). 13C
NMR (DMSO-d6) δ 169.7, 140.3, 137.5, 134.6, 131.6, 128.3, 128.2,
126.5, 122.6, 117.7, 115.9, 52.0, 28.9. HRMS (FAB) calcd for
C15H16NO4S [M + H]+, 306.08000; found, 306.07886. Anal.
(C15H15NO4S) C, H, N.
°C. H NMR (MeOD) δ 7.70 (m, 2H), 7.54 (t, J ) 8.4 Hz, 1H),
7.21 (t, J ) 7.5 Hz, 1H), 3.18 (t, J ) 7.8 Hz, 2H), 1.77 (m, 2H),
1.23 (m, 10H), 0.89 (t, J ) 7.5 Hz, 3H). 13C NMR (MeOD) δ
141.8 (d, J ) 7.0 Hz), 134.3 (d, J ) 2.7 Hz), 134.1 (d, J ) 6.8
Hz), 120.4 (d, J ) 178 Hz), 119.6 (d, J ) 10.8 Hz), 52.6, 32.8,
29.9, 29.9, 29.0, 24.3, 23.5, 14.3. HRMS (FAB) calcd for
C14H25NO5PS [M + H]+, 350.11911; found, 350.11826. Anal.
(C14H24NO5PS) C, H, N.
General Procedure for 19a-c. The starting bromide 18 (1.96
mmol) was added to a round-bottomed flask containing diethyl
phosphite (2.35 mmol), tetrakis(triphenylphosphine)palladium(0)
General Procedure for 23a-f. To a stirring solution of the
aniline starting material (3.3 mmol) in CH2Cl2 (12 mL) at 0 °C
was added pyridine (7.5 equiv). The sulfonyl chloride (1.2 equiv)

3326 Journal of Medicinal Chemistry, 2009, Vol. 52, No. 10
Wydysh et al.
was then added slowly via syringe. The solution was stirred and
allowed to warm to room temperature. Reaction progress was
monitored by TLC (20% EtOAc in hexanes). When complete, the
reaction was poured into saturated NaHCO3 solution (45 mL),
extracted with CH2Cl2 (3 × 15 mL), and washed with 1 M HCl
(50 mL). The combined organic phases were concentrated in vacuo
and separated by flash chromatography (20% EtOAc in hexanes)
to afford 23a-f.
29.9, 28.8, 24.4, 23.7, 14.4. HRMS (FAB) calcd for C21H35NO4S
[M]+, 397.22835; found, 397.22835. Anal. (C21H35NO4S·1/4(H2O))
C, H, N.
2-(Hexadecylsulfonamido)benzoic Acid 24c. mp ) 126-128
°C. 1H NMR (MeOD) δ 8.12 (d, J ) 7.6 Hz, 1H), 7.74 (d, J ) 8.4
Hz, 1H), 7.59 (t, J ) 8.0 Hz, 1H), 7.17 (t, J ) 7.6 Hz, 1H), 3.19
(t, J ) 7.6 Hz, 2H), 1.73 (m, 2H), 1.23 (m, 26H), 0.91 (t, J ) 7.2
Hz, 3H). 13C NMR (MeOD) δ 169.8, 140.7, 134.6, 131.6, 122.4,
117.3, 115.6, 50.9, 31.2, 29.0, 29.0, 29.0, 29.0, 29.0, 28.9, 28.8,
28.7, 28.5, 28.2, 27.0, 22.8, 22.0, 13.8. HRMS (FAB) calcd for
C23H40NO4S [M + H]+, 426.26781; found, 426.26825. Anal.
(C23H39NO4S) C, H, N.
Methyl 2-(Methylsulfonamido)benzoate 23a. 1H NMR (CDCl3)
δ 10.43 (s, 1H), 8.04 (d, J ) 8.0 Hz, 1H), 7.71 (d, J ) 8.0 Hz,
1H), 7.54 (t, J ) 8.4 Hz, 1H), 7.11 (t, J ) 7.6 Hz, 1H), 3.91 (s,
3H), 3.05 (s, 3H). 13C NMR (CDCl3) δ 168.2, 140.7, 134.8, 131.4,
122.7, 117.9, 115.3, 52.4, 39.8.
5-Chloro-2-(nonylsulfonamido)benzoic Acid 24d. mp )
1
101-103 °C. H NMR (MeOD) δ 8.05 (d, J ) 2.8 Hz, 1H), 7.74
Methyl 2-(Tetradecylsulfonamido)benzoate 23b. 1H NMR
(CDCl3) δ 10.42 (s, 1H), 8.03 (d, J ) 8.0 Hz, 1H), 7.74 (d, J )
8.4 Hz, 1H), 7.51 (t, J ) 8.4 Hz, 1H), 7.08 (t, J ) 7.6 Hz, 1H),
3.91 (s, 3H), 3.12 (t, J ) 8.0 Hz, 2H), 1.78 (m, 2H), 1.23 (m,
22H), 0.87 (t, J ) 7.2 Hz, 3H). 13C NMR (CDCl3) δ 168.2, 141.0,
134.7, 131.4, 122.4, 117.6, 114.9, 52.4, 52.0, 31.8, 29.5, 29.5, 29.5,
29.4, 29.3, 29.2, 29.0, 28.8, 27.9, 23.2, 22.5, 14.0.
(d, J ) 9.2 Hz, 1H), 7.59 (dd, J ) 9.2, 2.8 Hz, 1H), 3.21 (t, J )
8.0 Hz, 2H), 1.72 (m, 2H), 1.23 (m, 12H), 0.90 (t, J ) 7.2 Hz,
3H). 13C NMR (MeOD) δ 170.1, 141.2, 135.5, 132.4, 128.9, 120.6,
118.0, 52.5, 32.9, 30.2, 30.1, 29.9, 28.8, 24.4, 23.6, 14.4. HRMS
(FAB) calcd for C16H24ClNO4S [M]+, 361.11146; found, 361.11063.
Anal. (C16H24ClNO4S) C, H, N.
5-Hydroxy-2-(octylsulfonamido)benzoic Acid 24e. mp )
Methyl 2-(Hexadecylsulfonamido)benzoate 23c. 1H NMR
(CDCl3) δ 10.42 (s, 1H), 8.05 (d, J ) 8.0 Hz, 1H), 7.76 (d, J )
8.4 Hz, 1H), 7.54 (t, J ) 8.0 Hz, 1H), 7.11 (t, J ) 8.0 Hz, 1H),
3.94 (s, 3H), 3.14 (t, J ) 8.0 Hz, 2H), 1.81 (m, 2H), 1.26 (m,
26H), 0.88 (t, J ) 7.2 Hz, 3H). 13C NMR (CDCl3) δ 168.3, 141.0,
134.8, 131.4, 122.4, 117.7, 115.0, 52.4, 52.1, 31.8, 29.6, 29.6, 29.6,
29.6, 29.5, 29.5, 29.4, 29.3, 29.1, 28.9, 28.0, 23.3, 22.6, 14.0.
Methyl 5-Chloro-2-(nonylsulfonamido)benzoate 23d. 1H NMR
(CDCl3) δ 10.31 (br s, 1H), 8.01 (d, J ) 2.4 Hz, 1H), 7.73 (d, J )
9.0 Hz, 1H), 7.48 (dd, J ) 9.0, 2.4 Hz, 1H), 3.95 (s, 1H), 3.12 (t,
J ) 7.8 Hz, 2H), 1.78 (m, 2H), 1.23 (m, 12H), 0.87 (t, J ) 7.2 Hz,
3H). 13C NMR (CDCl3) δ 167.3, 139.6, 134.6, 131.0, 127.8, 119.2,
116.2, 52.8, 52.3, 31.7, 29.0, 28.8, 27.9, 27.9, 23.2, 22.5, 14.0.
Methyl 5-Hydroxy-2-(octylsulfonamido)benzoate 23e. 1H NMR
(CDCl3) δ 9.91 (s, 1H), 7.62 (d, J ) 9.0 Hz, 1H), 7.52 (d, J ) 3.0
Hz, 1H), 7.07 (dd, J ) 3.0, 9.0 Hz, 1H), 6.36 (s, 1H), 3.91 (s, 3H),
3.05 (t, J ) 8.1 Hz, 2H), 1.76 (m, 2H), 1.22 (m, 10H), 0.86 (t, J
) 7.2 Hz, 3H). 13C NMR (CDCl3) δ 168.0, 151.7, 133.3, 122.3,
120.7, 117.3, 117.0, 52.6, 51.7, 31.5, 28.8, 28.7, 27.9, 23.1, 22.4,
13.9.
1
142-144 °C. H NMR (MeOD) δ 7.56 (d, J ) 8.8 Hz, 1H), 7.51
(d, J ) 2.8 Hz, 1H), 7.03 (dd, J ) 8.8, 2.8 Hz, 1H), 3.07 (t, J )
8.0 Hz, 2H), 1.68 (m, 2H), 1.23 (m, 10H), 0.89 (t, J ) 7.2 Hz,
3H). 13C NMR (MeOD) δ 171.0, 154.6, 134.1, 122.8, 121.9, 119.2,
118.5, 53.1, 32.8, 29.9, 29.8, 28.8, 24.3, 23.6, 14.4. Anal.
(C15H23NO5S) C, H, N.
5-Fluoro-2-(octylsulfonamido)benzoic Acid 24f. mp ) 141-143
1
°C. H NMR (MeOD) δ 7.77 (m, 2H), 7.38 (m, 1H), 3.17 (t, J )
8.0 Hz, 2H), 1.71 (m, 2H), 1.23 (m, 10H), 0.88 (t, J ) 7.2 Hz,
3H). 13C NMR (MeOD) δ 170.2 (d, J ) 1.8 Hz), 159.2 (d, J )
241 Hz), 138.6 (d, J ) 2.7 Hz), 122.7 (d, J ) 22.7 Hz), 121.5 (d,
J ) 7.6 Hz), 119.0 (d, J ) 6.9 Hz), 118.8 (d, J ) 24.1 Hz), 52.4,
32.8, 29.9, 29.9, 28.8, 24.4, 23.6, 14.3. HRMS (FAB) calcd for
C15H22FNO4S [M]+, 331.12536; found, 331.12445. Anal.
(C15H22FNO4S) C, H, N.
GPAT Assay. The mtGPAT assay has been reported previ-
ously.35 A mitochondrial preparation of glycerol 3-phosphate
acyltransferase was added to the incubation mixture containing 14C-
labeled glycerol 3-phosphate, palmitoyl-CoA, and varying inhibitor
concentrations to initiate the reaction. After 10 min, the reaction
was terminated by adding chloroform, methanol, and 1% perchloric
acid. Five min later, more chloroform and perchloric acid were
added, and the upper aqueous layer was removed. After washing
three times with 1% perchloric acid, the organic layer was
evaporated under nitrogen and the amount of 14C present was
counted to determine the extent of reaction inhibition. Data points
were recorded in triplicate, and IC50 values were calculated based
on the amount of test inhibitor necessary to produce 50% of
mtGPAT activity observed in the absence of inhibitor but in the
presence of DMSO vehicle control.
Methyl 5-Fluoro-2-(octylsulfonamido)benzoate 23f. 1H NMR
(CDCl3) δ 10.15 (s, 1H), 7.75 (m, 2H), 7.25 (m, 1H), 3.95 (s, 3H),
3.09 (t, J ) 8.0 Hz, 2H), 1.76 (m, 2H), 1.22 (m, 10H), 0.85 (t, J
) 6.8 Hz, 3H). 13C NMR (CDCl3) δ 167.2 (d, J ) 2.2 Hz), 157.5
(d, J ) 242 Hz), 137.1 (d, J ) 2.8 Hz), 122.0 (d, J ) 22.4 Hz),
120.1 (d, J ) 7.4 Hz), 117.4 (d, J ) 24.3 Hz), 116.4 (d, J ) 6.9
Hz), 52.7, 52.1, 31.5, 28.7, 28.7, 27.9, 23.2, 22.4, 13.8.
General Procedure for 24a-f. To a stirring suspension of
potassium t-butoxide (5.88 mmol) in Et2O (15 mL) cooled to 0 °C
was added water (1.4 mmol) via syringe. The slurry was stirred
for 5 min, and 23a-f (0.67 mmol) was added. The mixture was
stirred at room temperature until starting material disappeared by
TLC analysis (20% EtOAc in hexanes). Ice water was added until
two clear layers formed. The aqueous layer was separated and
acidified with 1 M HCl, and the product was extracted with Et2O
(3 × 20 mL) and evaporated in vacuo. If necessary, the product
was then recrystallized (EtOAc/hexanes) to afford pure 24a-f.
2-(Methylsulfonamido)benzoic Acid 24a. mp ) 187-189 °C.
1H NMR (MeOD) δ 8.11 (d, J ) 8.0 Hz, 1H), 7.70 (d, J ) 8.0 Hz,
1H), 7.60 (t, J ) 7.2 Hz, 1H), 7.17 (t, J ) 7.6 Hz, 1H), 3.08 (s,
3H). 13C NMR (MeOD) δ 171.2, 142.2, 135.7, 133.0, 123.9, 119.2,
117.3, 39.9. HRMS (FAB) calcd for C8H9NO4S [M]+, 215.02523;
found, 215.02576. Anal. (C8H9NO4S) C, H, N.
Acknowledgment. The work was supported by the NIH
1R43DK65423 to FASgen, Inc. Under a license agreement
between FASgen, Inc. and The Johns Hopkins University,
C.A.T. is entitled to share royalty received by the University
on sales of products described in this article. C.A.T. owns
FASgen, Inc. stock, which is subject to certain restrictions under
university policy. The Johns Hopkins University, in accordance
with its conflict of interest policies, is managing the terms of
this arrangement.
Supporting Information Available: Elemental analysis data for
target compounds 5a-5f, 13a-13f, 15a-15i, 17a-17f, 21a-21c,
24a-24f. This material is available free of charge via the Internet
at http://pubs.acs.org.
2-(Tetradecylsulfonamido)benzoic Acid 24b. mp ) 120-122
°C. 1H NMR (MeOD) δ 8.12 (d, J ) 8.0 Hz, 1H), 7.74 (d, J ) 8.4
Hz, 1H), 7.59 (t, J ) 7.6 Hz, 1H), 7.17 (t, J ) 7.6 Hz, 1H), 3.19
(t, J ) 8.0 Hz, 2H), 1.70 (m, 2H), 1.29 (m, 22H), 0.91 (t, J ) 6.8
Hz, 3H). 13C NMR (MeOD) δ 171.4, 142.5, 135.7, 133.1, 123.8,
118.8, 117.0, 52.2, 33.0, 30.7, 30.7, 30.7, 30.6, 30.5, 30.4, 30.2,
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