Synthesis and evaluation of a series of 1,4-diarylbutadienes for anticoccidial activity

Article abstract of DOI:10.1016/S0968-0896(03)00330-4

During the course of a collaborative screening program, a set of 1-phenyl-4-pyridyl-butadienes was found to exhibit in vitro activity against Eimeria tenella in a cell-based assay. Activity was dependent on the chain length and degree of unsaturation of t

Full text of DOI:10.1016/S0968-0896(03)00330-4

Bioorganic & Medicinal Chemistry 11 (2003) 4083–4091
Synthesis and Evaluation of a Series of 1,4-Diarylbutadienes
for Anticoccidial Activity
y
Jennifer L. Gage,* Herbert A. Kirst, Deirdre O’Neil, Bridget A. David,
Charles K. Smith, II and Sharon A. Naylor
Elanco Animal Health Research and Development, A Division of Eli Lilly & Co., 2001 West Main Street,
Greenfield, IN 46140-0708, USA
Received 3 March 2003; revised 5 May 2003; accepted 9 May 2003
Abstract—During the course of a collaborative screening program, a set of 1-phenyl-4-pyridyl-butadienes was found to exhibit in
vitro activity against Eimeria tenella in a cell-based assay. Activity was dependent on the chain length and degree of unsaturation of
the linker between the two aryl groups as well as substitution of the pyridine moiety. Structure–activity relationship studies were
subsequently conducted over a larger range of 1,4-diarylbutadienes in order to determine the scope of active compounds, to identify
structural patterns governing activity and to enhance in vitro potency against E. tenella. In addition, the efficacy of many com-
pounds for treating coccidiosis in chickens was measured by testing the ability of the compound to prevent or reduce intestinal and
cecal lesions when administered by oral gavage. A few compounds in the series were identified that exhibited a moderate degree of
in vitro and in vivo activity.
#
2003 Elsevier Ltd. All rights reserved.
Introduction
of in vivo efficacy against coccidiosis usually remains elu-
8
sive. Consequently, the search for efficacious new antic-
occidial agents has proven to be a very challenging goal for
both human and animal health research programs.
Cryptosporidiosis (‘crypto’) is caused by Cryptospor-
idium parvum, a coccidian protozoan, and has been
reported to be one of the most common causes of ill-
nesses transmitted by water sources in the US, Crypto is
a serious illness that can be fatal in children or those
with compromised immune systems. There is currently
no treatment for cryptosporidiosis except for supportive
therapy for the diarrhea and dehydration that accom-
panies this disease. Eimeria sp. is also a coccidian para-
site and is the causative agent of coccidiosis in poultry.
The anticoccidial market for poultry is currently domi-
nated by members of the polyether class of anti-
During the course of a collaborative screening program
designed to identify new antiparasitic agents, a series of
diarylbutadienes, provided by Idemitsu Kosan Com-
9
pany, was found to exhibit moderate anticoccidial
activity in a cell-based in vitro assay system. Since such
a series of compounds had not been previously reported
to possess anticoccidial activity, the series was further
explored through in vivo testing and structure–activity
relationship studies.
1
,2
biotics, but the possibility for emergence of resistance
to these agents always looms as a potential threat to
3
their continued effectiveness. Despite continuous
reports in the literature describing the discovery and
evaluation of newer agents exhibiting in vitro activity
Results and Discussion
Representative structures from the initial set of com-
9
4ꢀ7
against species of Eimeria,
successful demonstration
pounds synthesized at Idemitsu Kosan that were
screened for biological activity against E. tenella are
illustrated in Figure 1. The in vitro anticoccidial activ-
ities of these compounds are listed in Table 1. Com-
pounds were tested in vitro at an initial concentration of
10 mg/mL, and if active at that concentration, were then
tested at 5 and 2.5 mg/mL. Analysis of the screening
*Corresponding author at current address: CEPTYR, Inc. 3830 Monte
Villa Parkway, Suite 200, Bothell, WA 98021, USA. Tel.: +1-425-806-
1
521; fax: +1-425-806-1601; e-mail: jgage@ceptyr.com
y
Retired: current address is 7840 West 88th St., Indianapolis, IN
46278, USA.
0
968-0896/03/$ - see front matter # 2003 Elsevier Ltd. All rights reserved.
doi:10.1016/S0968-0896(03)00330-4

4084
J. L. Gage et al. / Bioorg. Med. Chem. 11 (2003) 4083–4091
results revealed several intriguing relationships between
structures and activities. All of the compounds that
exhibited activity contained the 3-ethylpyridine ring
whereas all compounds lacking the 3-ethyl substituent
on the pyridine ring were inactive at the screening con-
centration. However, the presence of the 3-ethyl sub-
stituent was not sufficient by itself to confer activity, as
evidenced by compounds 4b and 5. To exhibit activity,
the nature and size of the linker that connected the
two aryl groups (compounds 8–11) with the exception
of compound 3b. These relatively unusual and unex-
pected relationships prompted further critical exami-
nation of the series, both by (1) synthesis and testing of
additional compounds to more fully assess the para-
meters governing in vitro activity, and (2) in vivo eval-
uation of the active compounds for the treatment of
coccidiosis in chickens.
3
-ethylpyridine ring to the phenyl ring was also critical.
This linker could be either a dienyl moiety (compound
, screening sample) or an alkyl moiety of a certain
Both butadiene 1 and saturated derivatives 2, 3a, 3b
and 4a demonstrated activity in vitro, however com-
pound 1 was selected for structural modification due to
the in vitro cellular toxicity observed with most of the
latter derivatives. Condensation, Wittig and Horner–
Emmons reactions are typical (but not all-inclusive)
methods for the synthesis of 1-phenyl-4-pyridyl-buta-
dienes with disconnection at either double bond. We
wanted to use methodology that would be applicable to
the synthesis of a variety of 4-arylphenylbutadienes.
Compounds 1 (freshly synthesized), 15, 17 and 18 were
synthesized via a condensation reaction with 3-ethyl-4-
methyl pyridine and the corresponding cinnamaldehyde
in the presence of NaOAc in refluxing acetic anhydride
in poor yield (5–13%) after extensive purification. Our
experimentation with condensation methodology
demonstrated that these reactions, in general, were low-
yielding and difficult to scale. The Wittig and Horner–
Emmons reactions, therefore were appealing. McDo-
nald & Campbell reported the construction of aniline-
containing 4-arylphenylbutadienes using convenient and
1
length (compounds 2, 3a, 3b and 4a). Compounds did
not exhibit activity if they either lacked the fully unsa-
turated butadienyl moiety (compounds 5–11) or pos-
sessed a smaller than optimal alkyl linker between the
1
0
scalable Wittig conditions. We sought to extend this
methodology to the synthesis of 4-pyridyl and 4-aryl-
phenylbutadienes.
Scheme 1 outlines the construction of 4-arylphenylbu-
tadienes (14) with arylcarboxaldehydes or aryl ketones
(
12) and cinnamyltriphenylphosphonium halides (13a,
1
2
3b) with LiOEt in EtOH. Compounds 16, 19, 20, 22,
4b, 25b, 29, 30, 34 and 36 (Tables 2 through 5) were
synthesized using this methodology. Products from
these reactions were often isolated by precipitation.
Isomerization of the diastereomeric mixture (14a/b)
with iodine followed by recrystallization gave pure all
trans products (14b) or all trans enriched products.
Although compounds 21, 26–28, 31–33 and 35 were
obtained from an internal compound collection, these
diarylbutadienes could also presumably be synthesized
by the Wittig methodology. Compound 23 was synthe-
sized by alkylation of 3-ethyl-4-methyl pyridine with
Figure 1.
Table 1. In vitro anticoccidial activity of compounds in Figure 1
a
No.
MEC (mg/mL) in vitro
1
2
3
3
4
4
5
6
7
8
8
8
9
1
1
(screening sample)
2.5, 10
2.5 (cytotoxic)
10
2.5 (cytotoxic)
2.5 (cytotoxic)
>10
a (n=3)
b (n=2)
a (X=3-Cl)
b (X=4-Cl)
>10
>10
>10
>10
>10
>10
>10
>10
a (X=Cl)
b (X=Me)
c (X=OMe)
0
1
>10
aMEC=Minimum effective concentration.
Scheme 1.

J. L. Gage et al. / Bioorg. Med. Chem. 11 (2003) 4083–4091
4085
3-bromo-1-phenyl propene in the presence of LDA.
Compounds 37–40 are either commercially available or
have been previously reported in the literature.
compounds that were tested in vitro more than once,
both data points are given. Most compounds tested
multiple times in vitro gave numerical results within one
dilution factor; two of these, however did not demon-
strate consistent activity in the in vitro assay.
Compounds in these studies all have the E,E butadiene
configuration where either configuration is possible.
This feature holds true for all of the compounds in
Tables 2–5, with the exception of compound 36 which is
a mixture of E,E and Z,E in a 2.5:1 ratio. For those
Several compounds were tested in vivo in a coccidiosis
mixed-infection model in young chicks. The chicks were
infected with both Eimeria acervulina and Eimeria
tenella on study day 2, which are known to cause lesions
in the intestinal portion of the gastrointestinal tract and
the cecum, respectively. On days 1–9, the chicks were
dosed once per day with the test compound adminis-
tered by oral gavage. The dose levels were 33 mg/kg or
Table 2. Anticoccidial activity of 1-phenyl-4-pyridyl-butadienes and
analogues
67 mg/kg, which approximates the amount of com-
pound that a chick would be estimated to receive from
daily consumption of that compound in its feed at a
concentration of 100 mg/g or 200 mg/g, respectively.
Necropsy occurred on study day 9, at which time the
intestine and cecum of each bird were examined for
lesions.
No.
R
1
R
2
MEC
mg/mL)
in vitro
MEC
(mg/g)
in vivo
a
(
1b
Et
Et
H
H
5, >10
>200 (i)c
>
200 (c)
100 (i)
Table 2 illustrates the initial group of 1-phenyl-4-pyr-
idyl-butadienes studied. Compound 1 (synthesized at
Elanco), which was the most active and least cytotoxic
compound in vitro from the first series, was tested in
vivo, but unfortunately it did not exhibit activity at the
highest concentrations tested. This compound was tes-
ted in vitro twice, however neither data point was
equivalent to the activity observed with 1 (screening
sample). Both compounds were determined to be of
high purity, therefore this inconsistency remained
unsolved. It was discovered, however that compound 15
having an ortho-methoxy substituted phenyl ring
demonstrated some in vivo activity against coccidiosis
even though it was devoid of in vitro activity. It was
therefore suspected that the active species in vivo might
be a metabolite of 15. Consequently, most of the buta-
dienes in Table 2 were tested in vivo in parallel to in
vitro testing in order to determine whether this phe-
nomenon was generally true with this class of com-
pounds. This property was not found to be
characteristic of the other butadienes tested whose in
15
16
17
18
OMe
OMe
>10, >10
>10
100 (c)
>200 (i)
>
200 (c)
200 (i)
Et
H
NO
H
2
5, >10
5, 10
1
00 (c)
d
200 (i)
00 (c)
2
1
2
2
2
2
2
2
9
10
>200 (i)
>200 (c)
>200 (i)
0
>10
10
>
>
200 (c)
150 (i)
1
150 (c)
2
NTe
>10
>10
>10
>200 (i)
>200 (c)
>200 (i)
3
Table 3. Anticoccidial activity of 1-phenyl-4-(nitrophenyl)-butadienes
>200 (c)
>200 (i)
4b
5b
No.
R
1
R
2
MEC (mg/mL)
in vitro
MEC (mg/g)
in vivo
>
200 (c)
NT
26
27
28
29
30
p-NO
o-NO
p-NO
p-NO
2
2
2
2
o-OMe
o-OMe
>10
>10
>10
>10
>10
>200 (i)
>
200 (c)
>200 (i)
200 (c)
>200 (i)
200 (c)
>200 (i)
200 (c)
>200 (i)
200 (c)
>
a100 mg/g and 200 mg/g refer to approximate doses if mixed into feed.
Compounds were administered via oral gavage at 33 mg/kg or 67 mg/
kg, respectively, to approximate these values.
p-NO
2
>
H
b
Freshly synthesized.
>
c
(
i)=intestine, (c)=cecum.
m-NO
2
H
d
Tested as a topdress on feed.
NT=not tested.
>
e

4086
J. L. Gage et al. / Bioorg. Med. Chem. 11 (2003) 4083–4091
vivo activity generally paralleled in vitro activity, and
the behavior of compound 15 remained an anomaly.
ortho-substituted derivative 21 was active both in vitro
and in vivo (against intestinal lesions at 150 mg/g). This
may indicate that the relationship between the nitrogen
location in the ring and the anticoccidial activity is an
electronic effect. Substitution of a second ortho-sub-
stituted pyridine moiety at the 4-butadiene position (22)
resulted in a loss of anticoccidial activity in vivo.
Saturation of the double bond conjugated to the pyri-
dine, compound 23, resulted in a total loss of activity.
Substitution of the pyridine heterocycle with a more
nitrogen-rich pyrazine (24b) or a p-excessive thiazole
(25b) provided derivatives devoid of activity. However,
it may also be argued that the methyl substitution at C-
4 in both of these compounds is responsible for the lack
of activity. Branching with a single carbon at this posi-
tion has not produced any active compounds, as
observed with compounds 5, 6, 8, 11 and 36 although
since the unsubstituted compounds were not synthesized
and tested, no direct comparison of substituted versus
unsubstituted derivatives can be made.
Although compound 15 demonstrated in vivo antic-
occidial activity, compound 16 which lacks the 3-ethyl
substituent on the pyridine moiety was devoid of both
in vitro and in vivo activity. This relationship between
3
-ethylpyridyl and pyridyl butadienes did not prove to
be generally true, however. For instance, compound 1
demonstrated in vitro activity, but no in vivo activity,
while its nor-ethyl counterpart, 18, had both in vitro
and in vivo activity (against both intestinal and cecal
lesions at 200 mg/g; 18 was tested as a topdress on feed).
Benzo-fused (quinoline) analogue 19 demonstrated in
vitro anticoccidial activity (and cellular toxicity), but
lacked in vivo activity against coccidiosis. The ortho-
nitrophenyl compound 17 showed modest activity both
in vitro and in vivo. The location of the nitrogen in the
pyridine ring was also examined. It was found that
meta-substituted derivative 20 was not active in vitro or
in vivo at the highest concentration tested while the
para-Nitrobenzene has generally been accepted as a
1
1
nonclassical bioisostere of pyridine, therefore several
p-nitrophenyl butadienes were synthesized (Table 3).
para-Nitrophenyl butadienes 26, 28, and 29 with o-
methoxy, p-nitro and H substitution on the 1-phenyl
ring, respectively, showed no activity either in vitro or in
vivo. Analogues of these compounds, 27 and 30, with
the nitro group positioned at the ortho and meta posi-
tions, respectively, were also inactive in vitro and in
vivo. It is readily apparent by the lack of anticoccidial
activity that the nitrophenyl group is not a bioisostere
for pyridine in this chemical series.
Table 4. Anticoccidial activity of 1-phenyl-4-(N,N-di-substituted-p-
aniline)-butadienes
No.
R
1
R
2
R
3
MEC (mg/mL) MEC (mg/g)
in vitro
in vivo
31
32
33
34
35
Me
Me
Me
Me
Me
Me
Me
Me
o-CN
p-CN
>10
>200 (i)
>
200 (c)
>200 (i)
200 (c)
>200 (i)
200 (c)
>200 (i)
A series of N,N-disubstituted-aniline conjugated buta-
dienes was also examined (Table 4). Compounds 31–34
containing N,N-dimethylaniline combined with cyano,
carboxy, and methoxy substitution on the phenyl ring
of the butadiene were synthesized and tested. Unfortu-
nately, these compounds proved to be inactive. The 4-
>10
>10
>10
>10
>
p-CO
2
H
>
o-OMe
>
200 (c)
NT
(
N,N-dimethylamino)phenyl-1-quinoline-butadiene 35
was also found to be inactive in vitro. Compound 36,
containing a para-morpholino substituent with a methyl
substituent at C-1 in the butadiene linker, was devoid of
biological activity.
36
>10
>200 (i)
200 (c)
>
In an effort to hold the butadiene linker in a con-
formationally restricted topology and render the buta-
diene chain aromatic (in two cases), several 2H-
benz[g]indazoles were examined (Table 5). In each of
these compounds, the 4-pyridyl substituent was kept
constant while the fused ring system was altered. Com-
pounds with unsaturation at C-4/C-5: 37 (CH SO H
Table 5. Anticoccidial activity of benz[g]indazoles
3
3
salt) and 38 (free base) had in vitro anticoccidial activity
at 5 and 1 mg/mL, respectively. However, no in vivo
anticoccidial activity was noted for compound 37. One
derivative having the aromaticity in the central ring of
its fused tricyclic system obliterated, compound 39, gave
consistent in vitro activity at 10 mg/mL. N-benzyl sub-
stituted analogue 40 demonstrated in vitro activity at 10
mg/mL as well. In summary, it was discovered that all of
the benz[g]indazoles tested demonstrated activity in
vitro, but these compounds lacked activity in vivo.
No.
R
H
C
4
–C
5
Bond type
MEC (mg/mL) MEC (mg/g)
in vitro
in vivo
37
Unsatd; CH
3
SO
3
H salt
ꢁ5
>200 (i)
>
200 (c)
NT
>200 (i)
3
3
8
9
H
H
Unsatd
Satd; CH SO
ꢁ1
3
3
H salt
10, 10
>
200 (c)
NT
40
Bn
Satd; HBr salt
10

J. L. Gage et al. / Bioorg. Med. Chem. 11 (2003) 4083–4091
4087
Conclusions
which are known to cause lesions in the intestinal por-
tion of the gastrointestinal tract and the cecum, respec-
tively. On study days 1 through 9, the compounds were
individually administered once daily to the infected
chickens by oral gavage as a solution or suspension in
DMSO/aqeuous Tween carrier (10%) [Aqeuous Tween
Moderate bioactivity was demonstrated with several 1-
phenyl-4-pyridyl-butadienes, but the in vitro and in vivo
anticoccidial activity was not always correlated (Table 2).
In one case, in vivo anticoccidial activity was observed
in the absence of in vitro activity (i.e., compound 15);
however, this feature was not consistently demonstrated
with all members of this chemical series. Substitution of
the pyridine with a pyrazine or a thiazole (24b and 25b)
did not result in anticoccidial activity. Nitrobenzene and
N,N-disubstituted-aniline did not prove to be bioiso-
steres for the pyridine ring as demonstrated with several
derivatives reported in Tables 3 and 4. Benz[g]indazoles
carrier is 0.5% methylcellulose/2% Tween 80/H O].
2
Solutions/suspensions were prepared fresh daily. The
dose levels were 33 mg/kg or 67 mg/kg, which approx-
imates administration of a compound in feed at a con-
centration of 100 mg/g or 200 mg/g, respectively.
Administration of the compound mixed in feed more
closely mimics potential commercial applications,
although at the early experimental stages of research,
administration of the compound by oral gavage pro-
vides a greater opportunity to elicit some degree of in
vivo efficacy. Necropsy occurred on study day 9. The
intestine and cecum of each bird were examined for
3
7–40 showed anticoccidial activity in vitro, but these
compounds were not active in vivo. Some interesting,
albeit modest, anticoccidial activity was observed with
several of the diaryl butadienes studied, however due to
the absence of a definitive lead compound and a clearly
defined direction for further optimization, the
anticoccidial studies with this series of compounds were
discontinued.
1
3
lesions. A lesion scoring system of 0–4 was used.
A
test compound was considered active if it prevented any
lesions from occurring at both sites of the gastro-
intestinal tract in all four chickens, or at least, if only
very minimal or occasional lesions were present.
Lesions in birds that received test compound were
compared and scored against results observed for
infected controls. Any mortality during the test period
was also recorded.
Experimental
In vitro assay
The cell culture medium used was Dulbecco’s Modified
Essential Medium (DMEM) containing 10% fetal
bovine serum (FBS). Bovine turbinate (BT) cells were
used for cell culture of Eimeria tenella. Lilly strain 65, a
polyether-tolerant strain of E. tenella was used as the
test organism. Freshly excysted, purified sporozoites
Synthesis of compounds
General methods. The original set of samples of this
series, compounds 1 (screening sample), 2–11, were
synthesized at Idemitsu Kosan Company by previously
9
described procedures. Samples of other previously
known compounds obtained from internal compound
1
2
were obtained as previously described. For purposes
4
1
1
of compound evaluation, 2ꢂ10 sporozoites were added
libraries were analyzed by H NMR and HRMS. H
NMR spectra were obtained on either a GE-300 or a
Varian 400 spectrometer in CDCl or DMSO-d with
TMS as the internal standard defined as 0.0 ppm. 2-D
NMR spectra were obtained on either a Bruker DRX-
500 or a Bruker Avance 500. Mass spectral data was
obtained on a VG 70 SE (EI), a Sciex API 100 (ESI), or
a Micromass LCT oa-TOF-MS (ESI).
per well to confluent cultures of BT cells maintained in
9
3
6-well tissue culture dishes which were incubated at
ꢃ
3
6
7 C. All compounds were initially solubilized in
DMSO at 10 mg/mL. These solutions were diluted in
cell culture medium to a final concentration of 10 mg/
mL, which was added to each treated well concurrent
with the introduction of sporozoites. All culture dishes
were then incubated for an additional 48 h. Following
incubation, all culture dishes were fixed with 5% acetic
acid–methanol for 15 min, and then washed and stained
with toluidine blue O for 30 min. After an additional
wash, each well was examined microscopically for the
presence of developing parasites (schizonts). Com-
pounds were designated active (significant reduction of
schizogony), inactive (no reduction) or cytotoxic
Compounds 18,14,15 19,16 and 20–2115 have been repor-
1
7
18
18,19
ted in the literature. Compounds 26–27, 28, 29,
2
0,21
22
23
30,
viously reported. Compounds 35
32 and the methyl ester of 33 have been pre-
26
2
4,25
27
38, and 39
have also been reported in the literature. Compound 39
is commercially available as the free base and 40 is also
commercially available.
(
destruction of host BT cells). Compounds that were
cytotoxic at 10 mg/mL were then tested at lower
concentrations.
3-Ethyl-4-[(E,E)-4-phenyl-1,3-butadienyl] pyridine (1).
Compound 1 was synthesized from 3-ethyl-4-methyl
pyridine and trans-cinnamaldehyde by the condensation
method described for compound 17 below. It was pur-
ified by chromatography (40–50% EtOAc–hexanes),
then rotary chromatography (50–75% EtOAc–hexanes
In vivo test
In each experiment, four chickens were used for each
compound and each dosage. 7 Day old male Hubbard
X Hubbard chickens were used for these studies. On
study day 2, the chickens were infected with a mixed
culture of 150,000 sporulated oocysts of Eimeria acer-
vulina and 50,000 sporulated oocysts of E. tenella,
with trace MeOH), then recrystallized from Et O–pen-
2
1
tane to give brown crystals (5% yield). H NMR
(300 MHz, CDCl ) d 1.25 (t, J=7.5, 3H), 2.75 (dd,
3
J=7.7, 15, 2H), 6.80 (t, J=15, 2H), 6.96–7.11 (m, 2H),
7.25–7.30 (m, 2H), 7.33–7.40 (m, 2H), 7.47 (d, J=7.7,

4088
J. L. Gage et al. / Bioorg. Med. Chem. 11 (2003) 4083–4091
2
H), 8.40 (d, J=3.3, 2H). MS (ESI+) m/z +236
+
concd in vacuo. The crude material was dissolved in
25% EtOAc–hexanes and filtered through silica in a 350
mL glass frit. The desired material eluted with 75%
EtOAc–hexanes. This crude product was chromato-
graphed (50% EtOAc–hexanes; rotary chromato-
(M+H) . Anal. calcd for C H N: C, 86.77; H, 7.28;
17 17
N, 5.95. Found: C, 86.53; H, 7.14; N, 5.95.
3
-Ethyl-4-[(E,E)-4-(2-methoxyphenyl)-1,3-butadienyl] pyri-
dine (15). Compound 15 was synthesized from 3-ethyl-4-
methyl pyridine and trans-2-methoxy cinnamaldehyde
by the condensation method described for compound 17
below. It was purified by chromatography (30–55%
graphy), then crystallized from Et O–pentane to obtain
2
dark red crystals (13% yield). H NMR (400 MHz,
1
CDCl ) d 1.25 (t, J=7.5, 3H), 2.75 (q, J=7.5, 2H), 6.93
3
(d, J=15.2, 1H), 7.00 (dd, J=10.6, 14.8, 1H), 7.11 (dd,
J=10.8, 15.2, 1H), 7.25–7.29 (m, 1H), 7.40–7.44 (m,
2H), 7.58–7.62 (m, 1H), 7.74 (dd, J=1.2, 8.0, 1H), 7.96
(dd, J=1.4, 8.0, 1H), 8.42–8.44 (m, 2H). MS (ESI+)
1
EtOAc–hexanes) to give an orange oil (9% yield). H
NMR (300 MHz, CDCl ) d 1.16 (t, J=7.5, 3H), 2.65 (q,
3
J=7.5, 2H), 3.79 (s, 3H), 6.69–7.18 (m, 7H), 7.16 (d,
J=5.2, 1H), 7.47 (dd, J=1.6, 7.7, 1H), 8.31–8.32 (m,
+
m/z 281 (M+H) . Anal. calcd for C H N O : C,
1
7
16
2
2
2
H). HRMS (ES+) m/z 266.1552 (calcd for
C H NO+H 266.1545). A second lot of 15 used for
72.84; H, 5.75; N, 9.99. Found: C, 72.54; H, 5.82; N,
9.68.
1
8
19
the second in vitro test (>10 mg/mL) gave identical
spectral data and HRMS obsd 266.1555.
4-[(E,E)-4-Phenyl-1,3-butadienyl] pyridine (18). Com-
pound 18 was synthesized from 4-picoline and trans-
cinnamaldehyde by the condensation method described
for compound 17 above. It was purified by chromato-
graphy (25–75% EtOAc–hexanes) then recrystallized
(
E)-o-Methoxy-cinnamyltriphenyl phosphonium bromide
13b). Triphenylphosphine (44.0 g, 167.7 mmol) was
(
dissolved in benzene (100 mL), then trans-1-(3-bromo-1-
2
8
propenyl)-2-methoxy benzene (35.5 g, 156.3 mmol)
was added as a solution in benzene (150 mL). The mix-
ture was stirred at room temperature for 16 h, then the
resulting white solid was collected by vacuum filtration,
rinsed with benzene–petroleum ether, and dried in a
from Et O–pentane to give an orange solid (12% yield).
2
1
H NMR (300 MHz, CDCl ) d 6.58 (d, J=15.5, 1H),
3
6.78 (d, J=15.4, 1H), 6.96 (dd, J=10.4, 15.4, 1H), 7.13
(dd, J=10.4, 15.4, 1H), 7.26–7.29 (m, 3H), 7.36 (dd,
J=7.2, 2H), 7.47 (d, J=7.0, 2H), 8.54 (d, J=5.5, 2H).
+
vacuum oven to give 60.3 g of white solid (79% yield).
1
MS (ESI+) m/z 208 (M+H) . Anal. calcd for
C H N: C, 86.92; H, 6.32; N, 6.76. Found: C, 86.63;
H NMR (400 MHz, DMSO-d ) d 3.38 (s, 3H), 3.71 (s,
6
15 13
H O), 4.84 (dd, J=7.6, 16.8, 2H), 6.12 (app dq, J=7.4,
H, 6.17; N, 6.58. This lot was tested for in vitro anti-
coccidial activity (Table 2) and gave a value of 5 mg/mL.
A second lot of 18 was tested for in vitro and in vivo
activity and gave values of 10 mg/mL, 200 mg/g (i) and
200 mg/g (c), respectively. The second lot of 18 gave
identical spectral data and the following analysis;
Found: C, 87.01; H, 6.36; N, 6.79.
2
1
3.6, 15.8, 1H), 6.88 (dd, J=7.6, 10.8, 1H), 6.88 (d,
J=16, 1H), 6.98 (d, J=8, 1H), 7.26 (t, J=7.2, 1H), 7.32
d, J=7.2, 1H), 7.37 (s, benzene), 7.78–7.84 (m, 15H);
(
1
3
C NMR (100 MHz, DMSO-d ) d 26.21, 26.69, 55.36,
6
1
1
1
11.25, 115.34, 115.44, 117.64, 118.48, 120.38, 123.89,
23.92, 126.85, 128.07, 129.40, 129.87, 130.00, 133.53,
33.63, 134.71, 134.74, 156.02.
4
-[(E,E) 4-Phenyl-1,3-butadienyl] quinoline (19). Pre-
1
0
4
(
-[(E,E)-4-(2-Methoxyphenyl)-1,3-butadienyl]
pyridine
16). Compound 16 was synthesized from pyridine 4-
viously published Wittig conditions were used. To
absolute ethanol (50 mL) was added 13a (7.0 g, 17
mmol) and 4-quinoline carboxaldehyde (2.36 g, 15
mmol) and stirred until all the starting materials dis-
solved. LiOEt (1.0 M in EtOH, 17 mL, 17 mmol) was
then added dropwise via syringe. Upon addition of
LiOEt, the reaction immediately turned dark brown.
The reaction was stirred at room temperature for 16 h
carboxaldehyde and 13b by the general Wittig method
described for compound 19. It was isolated by extrac-
tion, then isomerized with I in Et O and recrystallized
from hot DMF–EtOH–H O to give dark orange crys-
2
tals (31% yield). H NMR (400 MHz, CDCl ) d 3.89 (s,
2
2
1
3
3
H), 6.55 (d, J=15.6, 1H), 6.90 (d, J=8.4, 1H), 6.97
dd, J=8.2, 15.2, 1H), 7.01 (d, J=16.4, 1H), 7.14 (d,
J=15.6, 1H), 7.17 (dd, J=10.4, 15.6, 1H), 7.24–7.28 (m,
(
then diluted with H O and EtOAc and the layers were
2
separated. The organic layer was extracted with 10%
HCl, and the aqueous extract was washed with EtOAc.
The aqueous layer was made basic, then extracted into
EtOAc. The combined organics were washed with brine,
3
H), 7.52 (dd, J=1.6, 7.6, 1H), 8.53 (d, J=1.4, 1H),
+
8.54 (d, J=1.4, 1H). MS (EI+) m/z 238 (M ). Anal.
calcd for C H NO: C, 80.98; H, 6.37; N, 5.90. Found:
C, 80.57 (difference of 0.414%); H, 6.36; N, 6.12.
1
6
15
dried over MgSO , filtered and concd in vacuo. The
4
crude product was dissolved in Et O–toluene and stirred
2
3-Ethyl-4-[(E,E)-4-(2-nitrophenyl)-1,3-butadienyl] pyri-
dine (17). An oven-dried round bottom flask was
charged with Ac O (60 mL) and NaOAc (5.6 g, 68
2
with catalytic I for several days. A yellow solid was
2
isolated after concentration in vacuo. The crude pro-
duct was recrystallized from hot DMF–H O to obtain
2
1
mmol) to form a suspension. 3-Ethyl-4-methyl pyridine
2.3 g of a light yellow solid (60% yield). H NMR
(
(
3.6 mL, 34 mmol) and trans-2-nitro cinnamaldehyde
6.0 g, 34 mmol) were added and the mixture was
(400 MHz, CDCl ) d 6.83 (d, J=15.0, 1H), 7.11 (dd,
3
J=10.3, 15.0, 1H), 7.20 (dd, J=10.6, 15.3, 1H), 7.26–
7.31 (m, 1H), 7.36–7.40 (m, 3H), 7.49–7.60 (m, 4H),
7.70–7.75 (m, 1H), 8.13 (dd, J=0.7, 8.4, 1H), 8.17 (d,
refluxed for 21 h. The mixture was cooled to room
temperature and concd in vacuo to a slurry. The crude
reaction mixture was diluted with CH Cl , washed with
J=8.4, 1H), 8.87 (d, J=4.8, 1H). MS (EI+) m/z 258
+
2
2
H O, 5% HCl, water, then satd aqueous NaHCO .
2
(M ). Anal. calcd for C H N: C, 88.68; H, 5.88; N,
19 15
3
After drying over MgSO and filtering, the solution was
4
5.44. Found: C, 88.29; H, 5.86; N, 5.52.

J. L. Gage et al. / Bioorg. Med. Chem. 11 (2003) 4083–4091
4089
3
-[(E,E)-4-Phenyl-1,3-butadienyl] pyridine (20). Com-
7.18–7.35 (m, 5H), 8.35 (d, J=5.1, 1H), 8.39 (s, 1H).
HRMS (ES+) m/z 238.1607 (calcd for C H N+H
238.1597).
pound 20 was synthesized from 3-pyridine carbox-
aldehyde and 13a by the general Wittig method
described for compound 19. The product was isolated
1
7
19
by extractive workup (H O/EtOAc), then recrystallized
2
2-[(1E,3E)-1-Methyl-4-phenyl-1,3-butadienyl] pyrazine
(24b). Compound 24 was synthesized from 2-acetyl
pyrazine and 13a by the general Wittig method descri-
bed for compound 19. The product was isolated by
twice from DMF–H O to give compound 20 as a pale
2
1
beige powder (38% yield). H NMR (300 MHz; DMSO-
d6) d 6.75 (d, J=15.0, 1H), 6.79 (d, J=15.0, 1H), 7.11
(
(
dd, J=10.6, 15.0, 1H), 7.18–7.29 (m, 2H), 7.33–7.38
m, 3H), 7.53 (d, J=7.3, 2H), 7.94 (dt, J=1.8, 8.1, 1H),
extractive workup (H O/hexanes). Purification by Bio-
2
tage flash chromatography (0–30% EtOAc–CH Cl )
2
2
8
(
.43 (dd, J=1.5, 4.8, 1H), 8.69 (d, J=1.8, 1H); MS
ES+) m/z 208 (M+1). Anal. calcd for C H N: C,
yielded two lots: 24a as an orange oil (41% yield), which
solidified upon standing, and 24b as an orange solid
(42% yield). 24a was spectroscopically determined
(COSY, difference NOE) to be the (Z,E)-isomer, but it
isomerized in solution to ꢁ1:1 mixture of the (Z,E)-
and (E,E)-isomers. 24b was spectroscopically deter-
1
5
13
8
6
6.92; H, 6.32; N, 6.76. Found: C, 85.94; H, 6.18; N,
.74.
2-[(E,E)-4-Phenyl-1,3-butadienyl] pyridine (21). The
synthesis of compound 21 has been reported by Pie-
chucki.
J=11.4, 1H), 6.53 (t, J=11.4, 1H), 6.74 (d, J=15.4,
1
mined to be the (E,E)-isomer. 24b H NMR (400 MHz,
CDCl ) d 2.34 (3H, s), 6.85 (d, J=14.4, 1H), 7.21–7.37
1
5 1
H NMR (400 MHz, CDCl ) d 6.40 (d,
3
3
(m, 5H), 7.50 (dd, J=7.2, 1.6, 2H), 8.39 (d, J=2.8, 1H),
8.53 (dd, J=2.4, 1.6, 1H), 8.81 (d, J=1.6, 1H). MS
1
2
H), 7.11 (ddd, J=0.888, 4.8, 7.5, 1H), 7.23–7.26 (m,
H), 7.32 (t, J=7.5, 2H), 7.48 (dd, J=1.4, 7.7, 2H), 7.63
+
(ESI+) m/z 223 (M+H) . Anal. calcd for C H N :
2
15
14
(
(
(
dt, J=1.8, 7.5, 1H), 8.26 (dd, J=11.0, 15.8, 1H), 8.67
dd, J=0.88, 4.8, 1H). HRMS (ES+) m/z 208.1145
calcd for C H N+H 208.1127).
C, 81.05; H, 6.35; N, 12.60. Found: C, 80.72; H, 6.36; N,
12.63.
1
5
13
2
- [(E,E) - 1 - Methyl - 4 - phenyl - 1,3 - butadienyl] thiazole
2
-[(3E)-4-Phenyl-1-(2-pyridyl)-1,3-butadienyl] pyridine
22). Compound 22 was synthesized from di-2-pyridyl
(25b). Compound 25b was synthesized from 2-acetyl
thiazole and 13a by the general Wittig method described
for compound 19. The product was isolated by extrac-
(
ketone and 13a by the general Wittig method described
for compound 19. After stirring at room temp, H O was
2
tive workup (H O/hexanes) and concd in vacuo. It was
2
added and stirred for 48 h; the ppt was collected by
vacuum filtration and dried to yield a light yellow pow-
then purified by Biotage flash chromatography (100%
CH Cl ) and yielded two lots: 25a as a brown oil, which
solidified upon standing and 25b as a brown oil. 25b was
spectroscopically determined (COSY, difference NOE)
to be the (E,E)-isomer. 25a isomerized in solution to
2
2
1
der (45% yield). H NMR (400 MHz, CDCl ) d 6.92 (m,
3
2
0
H), 7.05 (dt, J=7.6, 0.8, 1H), 7.14 (ddd, J=7.6, 4.8,
.8, 1H), 7.21 (m, 1H), 7.27–7.35 (m, 5H), 7.39 (dt,
J=8.0, 1.2, 1H), 7.57 (dd, J=8.0, 2.0, 1H), 7.67 (ddd,
J=15.6, 12.0, 1H), 7.80 (td, J=8.0, 2.0, 1H), 8.63 (ddd,
J=4.8, 1.6, 0.8, 1H), 8.79 (ddd, J=4.8, 1.6, 0.8, 1H).
25b; the two lots were pooled to give 25b as a brown oil
1
(87% yield). 25b H NMR (400 MHz, CDCl ) d 2.39 (s,
3
3H), 6.81 (m, 1H), 7.14–7.29 (m, 4H), 7.35 (t, J=7.6,
2H), 7.49 (d, J=7.6, 2H), 7.80 (dd, J=3.2, 0.8, 1H). MS
+
(ESI+) m/z 228 (M+H) .
+
MS (ESI+) m/z 285 (M+H) . Anal. calcd for
C H N : C, 84.48; H, 5.67; N, 9.85. Found: C, 84.18;
H, 5.56; N, 9.41.
2
0
16
2
4-[(E,E)-4-(2-Methoxyphenyl)-1,3-butadienyl] nitroben-
zene (26). Compound 26 has been reported by Cheng et
3
-Ethyl-4-[(3E)-4-phenyl-3-butenyl] pyridine (23). An
1
7 1
oven-dried flask was charged with anhydrous THF (6
mL) and diisopropylamine (1.3 mL, 9.5 mmol) and
al. H NMR (400 MHz, CDCl ) d 3.81 (s, minor imp.,
3
0.24H), 3.90 (s, 3H), 6.68 (d, J=15.7, 1H), 6.91 (d,
J=8.2, 1H), 6.97 (t, J=7.4, 1H), 7.01–7.05 (m, 1H),
7.13 (d, J=10.6, 1H), 7.17 (d, J=10.2, 1H), 7.25–7.26
(m, 1H), 7.52–7.55 (m, 3H), 8.05 (d, J=8.8, minor imp.,
0.14H), 8.19 (d, J=9.0, 2H). ++ HRMS (ES+) m/z
282.1138 (calcd for C H NO +H 282.1131).
ꢃ
.5 mmol) was added dropwise and the reaction was
cooled to ꢁꢀ50 C. nBuLi (2.5 M in hexanes, 3.8 mL,
9
stirred for 10 min. 3-Ethyl-4-methyl pyridine (1.0 mL,
9
4
.4 mmol) was added, then the mixture was stirred for
ꢃ
ꢃ
0 min at ꢀ50 C and 45 min at ꢀ10 C. The mixture
1
7
15
3
ꢃ
was then cooled again to ꢀ50 C and a solution of 3-
bromo-1-phenyl propene (2.05 g, 9.4 mmol) in THF was
added dropwise. The reaction mixture was allowed to
warm slowly to room temperature and quenched with
2-[(E,E)-4-(2-Methoxyphenyl)-1,3-butadienyl] nitroben-
zene (27). Compound 27 has been reported by Cheng et
1
7 1
al. H NMR (400 MHz, CDCl ) d 3.88 (s, 3H), 6.88 (d,
3
H O after stirring for a total of 3 h. After dilution with
2
EtOAc, the organic layer was washed with H O, then
2
brine, then dried over MgSO , vacuum filtered through
4
J=8.2, 1H), 6.98 (dd, J=7.4, 14.5, 2H), 7.01–7.15 (m,
3H), 7.22–7.26 (m, 1H), 7.33 (dt, J=1.0, 7.7, 1H), 7.52
(dd, J=1.2, 7.0 1H), 7.55 (d, J=7.4, 1H), 7.71 (d,
J=7.8, 1H), 7.89 (dd, J=0.78, 8.2, 1H). HRMS (ES+)
m/z 282.1120 (calcd for C H NO +H 282.1131).
a layer of silica and Celite and concd in vacuo. The
crude product was chromatographed (50–75% EtOAc–
hexanes; rotary chromatography) to give 991 mg of a
1
7
15
3
Anal. calcd for C H NO : C, 72.58; H, 5.38; N, 4.98.
17 15 3
Found: C, 72.74; H, 5.43; N, 4.95.
1
brown oil (45% yield). H NMR (300 MHz, CDCl ) d
3
1
.24 (t, J=7.5, 3H), 2.50 (q, J=7.4, 2H), 2.68 (dd,
J=7.5, 15.2, 2H), 2.75–2.81 (m, 2H), 6.23 (dt, J=6.8,
5.8, 1H), 6.42 (d, J=15.9, 1H), 7.08 (d, J=5.1, 1H),
4-[(E,E)-4-(4-Nitrophenyl)-1,3-butadienyl] nitrobenzene
(28). The synthesis of compound 28 has been reported
1

4090
J. L. Gage et al. / Bioorg. Med. Chem. 11 (2003) 4083–4091
by Mitsudo et al.18 1H NMR (400 MHz, CDCl ) d 6.84
N,N-Dimethyl-4-[(E,E)-4-(2-methoxyphenyl)-1,3-butadie-
nyl] benzenamine (34). Compound 34 was synthesized
from 4-dimethylamino benzaldehyde and 13b by the
general Wittig method described for compound 19. The
3
(
(
2
4
dd, J=3.0, 12.1, 2H), 7.12 (dd, J=2.9, 12.1, 2H), 7.59
d, J=8.6, 4H), 8.22 (d, J=9.0, 4H). MS (FD+) m/z
96 (M ). Anal. calcd for C H N O : C, 64.86; H,
16 12 2 4
+
.08; N, 9.46. Found: C, 64.69; H, 4.21; N, 9.45.
product was isolated by extractive workup (H O/
2
EtOAc), then recrystallized from hot DMF–H O to give
2
1
4
-[(E,E)-4-Phenyl-1,3-butadienyl] nitrobenzene (29).
a white powder (45% yield). H NMR (400 MHz,
Compound 29 was synthesized from p-nitro benzalde-
hyde and 13a by the general Wittig method described
for compound 19. After cooling the rxn mixture, the ppt
was collected by vacuum filtration and dried to yield a
CDCl ) d 2.88–2.97 (m, 6H), 3.87 (s, 3H), 6.58 (d,
3
J=15.6, 1H), 6.69 (dt, J=2.0, 8.8, 2H), 6.79–7.0 (m,
3H), 6.95 (d, J=15.6, 1H), 7.16–7.20 (m, 1H), 7.33 (dt,
J=2.0, 8.8, 2H), 7.51 (dd, J=2.0, 7.6, 1H), 8.01 (s, 1H).
HRMS (ES+) m/z 280.1695 (calcd for C H NO+H
bright yellow solid. The crude product was recrys-
1
1
9
21
tallized from hot DMF–H O–EtOH (25% yield). H
2
280.1701).
NMR (400 MHz, CDCl ) d 6.71 (d, J=15.2, 1H), 6.81
3
(
d, J=15.2, 1H), 6.98 (dd, J=10.8, 15.2, 1H), 7.12 (dd,
J=10.8, 15.2, 1H), 7.30 (d, J=7.2, 1H), 7.37 (t, J=7.2,
H), 7.47 (d, J=7.2, 2H), 7.55 (d, J=9.2, 2H), 8.20 (d,
4-[(E,E) 4-(4-N,N-Dimethylaminophenyl)-1,3-butadienyl]
quinoline (35). Compound 35 was reported by both Shi-
2
4
25 1
2
bata and Pforr. H NMR (400 MHz, CDCl ) d 3.01
3
J=8.4, 2H). MS (ESI+) m/z 251 (M+H). Anal. calcd
for C H NO : C, 76.48; H, 5.22; N, 5.57. Found: C,
(s, 6H), 6.71 (d, J=8.6, 2H), 6.78 (d, J=15.3, 1H),
6.92–7.00 (m, 1H), 7.20–7.31 (m, 2H), 7.41 (d, J=9,
2H), 7.54 (d, J=16, 1H), 7.57 (t, J=7.4, 1H), 7.71 (t,
J=7.3, 1H), 8.10 (d, J=8.0, 1H), 8.20 (d, J=8.22, 1H),
8.85 (d, J=4.3, 1H). HRMS (ES+) m/z 301.1718 (calcd
for C H N +H 301.1705).
1
6
13
2
7
6.12; H, 5.13; N, 5.57.
3
-[(E,E)-4-Phenyl-1,3-butadienyl] nitrobenzene (30).
Compound 30 was synthesized from 3-nitro benzalde-
hyde and 13a by the general Wittig method described
for 19. After cooling the reaction mixture, the ppt was
2
1
20
2
Compound 36. Compound 36 was synthesized from 4-
morpholino benzaldehyde and 13a by the general Wittig
method described for compound 19 except that it was
refluxed during the reaction time. After cooling to room
collected by vacuum filtration and dried to give a solid
1
(
J=15.2, 1H), 6.78 (d, J=15.2, 1H), 6.97 (dd, J=10.4,
41% yield). H NMR (400 MHz, CDCl ) d 6.70 (d,
3
1
1
5.2, 1H), 7.08 (dd, J=10.4, 15.2, 1H), 7.29 (d, J=7.2,
H), 7.36 (t, J=7.2, 2H), 7.47 (d, J=7.2, 2H), 7.51 (d,
J=8.0, 1H), 7.72 (d, J=7.6, 1H), 8.07 (dd, J=1.6, 8.0,
temperature, H O was added and the yellow crystals
2
that resulted were collected by vacuum filtration. The
product was recrystallized from hot DMF–H O to give
2
+
1H), 8.29 (s, 1H). MS (EI+) m/z 251 (M ). Anal. calcd
for C H NO : C, 76.48; H, 5.22; N, 5.57. Found: C,
ꢁ1:1 mixture of isomers. After isomerization from I /
2
Et O/toluene with subsequent recrystallization, yellow
2
1
6
13
2
7
6.12; H, 5.12; N, 5.57.
crystals were obtained as ꢁ2.5:1 mixture of isomers
(26% yield). The stereochemistry of the isomers were
determined spectroscopically (ROESY, COSY). (1E,
2-[(E,E)-4-[4-(Dimethylamino)-phenyl]-1,3-butadienyl]
benzonitrile (31). This compound was obtained from an
internal compound library. H NMR (400 MHz, CDCl ) d
3E) is the major isomer (isomer A); (1Z,3E) is the minor
1
1
isomer (isomer B). H NMR (400 MHz, CDCl ) d 1.6 (s,
3
3
3
1
7
1
.00 (s, 6H), 6.67–6.72 (m, 3H), 6.84 (dd, J=10.2, 15.2,
H), 6.89 (d, J=16.0, 1H), 7.10 (dd, J=10.6, 15.2, 1H),
.21 (d, J=7.8, 1H), 7.35 (d, J=8.6, 2H), 7.50 (t, J=7.8,
H), 7.58 (d, J=7.8, 1H), 7.69 (d, J=8.2, 1H). HRMS
H O), 2.17 (s, 3H, isomer B), 2.25 (s, 3H, isomer A),
2
3.18–3.23 (m, 4H, A/B), 3.86–3.90 (m, 4H, A/B), 6.27
(d, J=11.2, 1H, isomer B), 6.53 (d, J=16, 1H, isomer
A), 6.63 (d, J=15.6, 1H, isomer A), 6.62 (dd, J=0.8,
11.2, 1H, isomer B), 6.88–6.98 (m, 2H), 7.16–7.35 (m,
6H), 7.43–7.46 (m, 3H). MS (ESI+) m/z 306
(ES+) m/z 275.1555 (calcd for C H N +H 275.1550).
Anal. calcd for C H N : C, 83.18; H, 6.61; N, 10.21.
Found: C, 83.09; H, 6.60; N, 10.09.
19 18 2
1
9
18
2
+
+
(M+H) . Anal. calcd for C H NO: C, 82.59; H,
21 23
7.59; N, 4.59. Found: C, 82.52; H, 7.57; N, 4.76.
4-[(E,E)-4-[4-(Dimethylamino)-phenyl]-1,3-butadienyl]
benzonitrile (32). The synthesis of compound 32 has
3-(4-Pyridinyl)-2H-benz[g]indazole mono methanesulfo-
nate (37). The synthesis of the free base form of com-
2
2 1
been reported by Singh et al.
H NMR (400 MHz,
2
6 1
CDCl ) d 2.99 (s, 6H), 6.52 (d, J=15.4, 1H), 6.66–6.70
pound 37 has been reported by Coombs et al.
NMR (400 MHz, DMSO-d ) 2.33 (s, 3H), 7.70 (dt,
H
3
(
1
m, 3H), 6.77 (dd, J=10.1, 15.4, 1H), 7.03 (dd, J=10.1,
5.8, 1H), 7.33–7.35 (m, 2H), 7.44 (d, J=8.4, 2H), 7.56
6
J=1.3, 7.9, 1H), 7.76 (dt, J=1.3, 7.9, 1H), 7.81 (d,
J=8.8, 1H), 8.12 (d, J=7.9, 1H), 8.27 (d, J=9.2, 1H),
8.54 (d, J=7.9, 1H), 8.62 (d, J=6.6, 2H), 8.93 (dt,
J=1.3, 6.6, 2H). HRMS (ES+) m/z 246.1029 (calcd for
C H N +H 246.1033).
(
(
dd, J=1.8, 8.4, 2H). HRMS (ES+) m/z 275.1541
calcd for C H N +H 275.1550).
1
9
18
2
4-[(E,E)-4-[4-(Dimethylamino)-phenyl]-1,3-butadienyl]
benzoic acid (33). The methyl ester of compound 33 has
1
6
11
3
2
3 1
been reported by Singh et al.
H NMR (400 MHz,
3-(4-Pyridinyl)-2H-benz[g]indazole (38). The synthesis of
2
6 1
DMSO-d ) d 2.93–2.94 (m, 6H), 6.63–6.72 (m, 4H), 6.86
compound 38 has been reported by Coombs et al.
H
6
(
7
dd, J=10.5, 15.2, 1H), 7.18 (dd, J=10.2, 15.2, 1H),
.35 (d, J=8.6, 2H), 7.55 (d, J=8.2, 2H), 7.86 (d,
J=8.2, 2H). HRMS (ES+) m/z 294.1498 (calcd for
NMR (400 MHz, CDCl ) d 7.63–7.70 (m, 3H), 7.95–
3
8.03 (m, 4H), 8.78 (d, J=5.9, 2H), 11.04 (br s, 1H).
HRMS (ES+) m/z 246.1041 (calcd for C H N+H
246.1033).
1
6
11
C H NO +H 294.1494).
9
1
19
2

J. L. Gage et al. / Bioorg. Med. Chem. 11 (2003) 4083–4091
4091
4
methylsulfonate (39). Compound 39 is commercially
,5-Dihydro-3-(4-pyridinyl)-2H-benz[g]indazole
mono
4. Watanabe, H.; Furuuchi, T.; Yamaguchi, T.; Kitahara, T.
Org. Lett. 1999, 1, 1079.
5. Armer, R. E.; Dutton, C. J.; Fenner, B. R.; Greenwood,
S. D. W.; Hall, K. T.; Rudge, A. J. Bioorg. Med. Chem. Lett.
available as the free base and has been reported by
2
7 1
Habeck et al. H NMR (400 MHz, DMSO-d ) d 2.31
6
1
6
998, 8, 139.
. Singh, S. B.; Zink, D. L.; Polishook, J. D.; Dombrowski,
(s, 3H), 3.01 (t, J=6.8, 2H), 3.09 (t, J=6.8, 2H), 7.30 (q,
J=6.8, 2H), 7.36 (t, J=8.0, 1H), 7.72 (d, J=7.2, 1H),
A. W.; Darkin-Rattray, S. J.; Schmatz, D. M.; Goetz, M. A.
Tetrahedron Lett. 1996, 37, 8077.
7. Shiomi, K.; Haneda, K.; Tomoda, H.; Iwai, Y.; Omura, S.
J. Antibiot. 1994, 47, 782.
8
2
.21 (2H), 8.86 (d, J=6.8, 2H). HRMS (ES+) m/z
48.1191 (calcd for C H N +H 248.1189).
1
6
34
3
4,5-Dihydro-2-(phenylmethyl)-3-(4-pyridinyl)-2H-benz[g]-
indazole mono hydrobromide (40). Compound 40 is
commercially available. H NMR (400 MHz, DMSO-
d6) d 2.99–3.03 (m, 2H), 3.10 (dt, J=1.8, 8.3, 2H), 5.85
8. Ricketts, A. P.; Olson, J. A.; Rice, J. R. Antimicrob. Agents
Chemother. 1992, 36, 2338.
9. Terada, I.; Matsuzaki, K.; Nonoshita, K.; Fujita, F. U.S.
Patent 5,262,420, 1993.
1
1
2
1
1
4
1
1
0. McDonald, R. N.; Campbell, T. W. J. Org. Chem. 1959,
4, 1969.
1. Thornber, C. W. Chem. Soc. Rev. 1979, 8, 563.
2. Smith, C. K., II; Strout, R. G. Exp. Parasitol. 1980, 50,
26.
(
7
1
s, 2H), 7.28–7.32 (m, 2H), 7.36 (t, J=7.5, 1H), 7.42–
.48 (m, 3H), 7.52–7.54 (m, 2H), 7.70 (dd, J=0.88, 7.5,
H), 8.39 (d, J=6.6, 2H), 9.10 (d, J=6.6, 2H). HRMS
(
ES+) m/z 338.1672 (calcd for C H N +H 338.1659).
23 29 3
3. Johnson, J.; Reid, W. M. Exp. Parasitol. 1970, 28, 30.
4. Carter, P. A. WIPO Patent 94/01403, 1994.
Acknowledgements
15. Piechucki, C. Synthesis 1976, 187.
6. Ahmed, S. A.; Hartmann, T.; Huch, V.; Du
Wahab, A. M. A. J. Phys. Org. Chem. 2000, 13, 539.
7. Cheng, L. T.; Wilson, T.; Marder, S. R.; Steigman, A. E.;
Rikken, G.; Spangler, C. W. J. Phys. Chem. 1991, 95, 10643.
1
¨
rr, H.; Abdel-
The authors would like to express great appreciation to
Idemitsu Kosan Co., Ltd for generously providing
research samples and information. The authors also
thank Mr. Douglas Kiehl and associates for mass spec-
trometric analyses, Mr. Jonathan Paschal and Mr.
Joseph Burkhart for 2-D spectroscopic stereochemical
determinations, and Mr. Bryan Maroska and Mr. Ken-
neth Poe for in vitro and in vivo coccidiosis tests. The
authors thank Dr. R. Bruce Hopkins, Dr. Nancy Jezyk,
Dr. Carlos Lamas, and Mr. William Thompson for
useful discussions.
1
1
1
1
8. Mitsudo, T.-A.; Fishetti, W.; Heck, R. F. J. Org. Chem.
984, 49, 1640.
9. Reddy, M. V. R.; Manjubhashini, A. B.; Reddy, S.;
Reddy, P. V. R.; Reddy, D. B. Synth. Commun. 1991, 21,
1
2
589.
0. Kamigata, N.; Ozaki, J. I.; Kobayashi, M. Chem. Lett.
1985, 705.
21. Kamigata, N.; Ozaki, J. I.; Kobayashi, M. J. Org. Chem.
1985, 50, 5045.
2
2
2
2
2
2. Singh, A. K.; Mahalaxmi, G. R. Photochem. Photobiol.
000, 71, 387.
3. Singh, A. K.; Darshi, M. Biochimica et Biophysics Acta
002, 1563, 35.
4. Shibata, T.; Hattori, T.; Onodera, S.; Kaino, T. Nippon
References and Notes
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