CP6679, a new injectable cephalosporin. Part1: Synthesis and structure-activity relationships

Article abstract of DOI:10.1016/S0968-0896(00)00214-5

A series of cephalosporins bearing a 5,5-fused ring system, an (imidazo[5,1-b]thiazolium-6-yl)methyl group, at the C-3 position were synthesized and evaluated for in vitro antibacterial activities. CP6679 (1s) and its analogues showed potent antibacterial activities against Gram-positive and Gram-negative bacteria, including Pseudomonas aeruginosa. They were also highly active against methicillin-resistant Staphylococcus aureus (MRSA). CP6679 (1s) showed more potent antibacterial activity than ceftazidime (CAZ) or cefpirome (CPR) against Pseudomonas aeruginosa and MRSA. Copyright (C) 2000 Elsevier Science Ltd.

Full text of DOI:10.1016/S0968-0896(00)00214-5

Bioorganic & Medicinal Chemistry 8 (2000) 2781±2789
CP6679, A New Injectable Cephalosporin.
Part1: Synthesis and Structure±Activity Relationships
Masaki Tsushima, Katsuyoshi Iwamatsu, Eijiro Umemura, Toshiaki Kudo,
Yasuo Sato, Sojiro Shiokawa, Hiromasa Takizawa, Yuko Kano, Kazuko Kobayashi,
Takashi Ida, Atsushi Tamura and Kunio Atsumi*
Pharmaceutical Research Center, Meiji Seika Kaisha, Ltd., 760 Morooka-cho, Kohoku-ku, Yokohama 222±8567, Japan
Received 19 June 2000; accepted 29 July 2000
AbstractÐA series of cephalosporins bearing a 5,5-fused ring system, an (imidazo[5,1-b]thiazolium-6-yl)methyl group, at the C-3
position were synthesized and evaluated for in vitro antibacterial activities. CP6679 (1s) and its analogues showed potent antibacterial
activities against Gram-positive and Gram-negative bacteria, including Pseudomonas aeruginosa. They were also highly active against
methicillin-resistant Staphylococcus aureus (MRSA). CP6679 (1s) showed more potent antibacterial activity than ceftazidime (CAZ)
or cefpirome (CPR) against Pseudomonas aeruginosa and MRSA. # 2000 Elsevier Science Ltd. All rights reserved.
Introduction
6. Next, the cephem nucleus 712 was acylated with 2-(5-
amino-1,2,4-thiadiazol-3-yl)-(Z)-2-¯uoromethoxyimino-
acetic acid13 by a known procedure2 to a€ord the amide
compound 8. The compound 8 was converted into the
tetravalent amino compound 9 through the corre-
sponding iodide intermediate by substitution with the
heterocyclic compound 6. The tetravalent amino com-
pound 9 was subjected to deprotection using tri¯uoro-
acetic acid and anisole to a€ord 1s (CP6679). Related
compounds were prepared similarly. The synthesis of
other heterocyclic compounds (3-substituted imidazo
[5,1-b]thiazoles and 5-substituted imidazo[5,1-b]thia-
zoles) will be reported elsewhere.
Nosocomial and opportunistic infections, mainly invol-
ving Pseudomonas aeruginosa and methicillin-resistant
Staphylococcus aureus (MRSA), have become a serious
clinical problem. To counter this, we have been searching
for novel cephalosporins with potent activity against these
organisms.1,2 Several active derivatives have recently been
reported by others.3 6 Some e€ective cephalosporin
agents3,4,7 9 are already clinically available, but new agents
are needed because of the problem of drug resistance.
Here we describe a novel cephalosporin, CP6679 (1s),
which has strong activity against both P. aeruginosa and
MRSA. In this paper, we present the synthesis and biolo-
gical activities of CP6679 (1s) and related compounds.10
Results and Discussion
We have synthesized a series of cephalosporins bearing a
(substituted imidazo[5,1-b]thiazolium-6-yl)methyl group
at the C-3 position (Fig. 1). We selected a 2-alkyloxy-
imino-2-(5-amino-1,2,4-thiadiazol-3-yl)acetamide group
for the C-7 position, because this group is known to be
favorable for potent antibacterial activities against
Gram-positive and Gram-negative bacteria including P.
aeruginosa.3,14 18 Then we introduced several 3-sub-
stituted imidazo[5,1-b]thiazole and 5-substituted imidazo
[5,1-b]thiazole groups, and evaluated the resultant com-
pounds. The results are shown in Tables 1 and 2. In
Table 1, compounds 1a±1g bearing a 3-substituted
imidazo [5,1-b]thiazole group showed potent anti-
bacterial activities against Gram-positive bacteria
Chemistry
Compound 1s (CP6679) was synthesized as shown in
Scheme 1. Treatment of (R)-N-Boc-alanine 3 with 2-
(aminomethyl)thiazole11 in the presence of 1-hydroxy-
benzotriazole (HOBT) and dicyclohexylcarbodiimide
(DCC) gave the acylated product 4. After replacement
of the protective group, 4 was cyclized in phosphorus
oxychloride (POCl3) to a€ord the imidazo[5,1-b]thiazole
5. Removal of the protective group and formylation
gave 5-[(R)-1-(formylamino)ethyl]imidazo[5,1-b]thiazole
*Corresponding author. Tel.: 045-541-2521; fax: 045-545-3193.
0968-0896/00/$ - see front matter # 2000 Elsevier Science Ltd. All rights reserved.
PII: S0968-0896(00)00214-5

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M. Tsushima et al. / Bioorg. Med. Chem. 8 (2000) 2781±2789
Scheme 1. Synthesis of 1s (CP6679).
except MRSA and Enterococcus hirae, and against
Gram-negative bacteria including P. aeruginosa. The
introduction of a substituent at the 3-position in the
heterocycle had little e€ect on the antibacterial activ-
ities. On the other hand, the compounds 1h±1o bearing
nothiazole group against Gram-positive bacteria except
MRSA. Among the compounds in Table 3, 1m had the
highest potency against MRSA and P. aeruginosa.
Furthermore, 1q showed the strongest activity against P.
aeruginosa, and therefore we synthesized derivatives with
a 2-(5-amino-1,2,4-thiadiazole-3-yl)-2-¯uoromethoxy-
iminoacetamide group at the C-7 position in an attempt
to improve the antibacterial activities against Gram-
positive bacteria, especially MRSA.
a
5-substituted imidazo[5,1-b]thiazole group also
showed potent antibacterial activities, although they
were inferior to those of the 3-substituted imidazo[5,1-b]
thiazole derivatives, as shown in Table 2. Among these
compounds, 1m showed superior antibacterial activity
against MRSA, so we selected 1m for further modi®ca-
tion and synthesized various derivatives.
Next, we introduced a methyl or a hydroxymethyl
group into the heterocycle at the C-3 position. The
results are shown in Table 4. The introduction of an
(R)-methyl or (R)-hydroxymethyl group (compounds 1s
and 1u) increased the antibacterial activities against
MRSA and P. aeruginosa. But the introduction of an
(S)-methyl or (S)-hydroxymethyl group (compounds 1t
and 1v) decreased the activity against P. aeruginosa.
Furthermore, the introduction of a dimethyl group
(compound 1w) decreased the activities against MRSA
and P. aeruginosa. The compounds 1s and 1u bearing
(R)-con®guration showed superior activities to those of
the compounds 1t and 1v bearing (S)-con®guration. No
di€erence in antibacterial activities was found between
Firstly, we replaced the C-7 side chain group. The
results are shown in Table 3. For a given alkyloxyimino
group in the C-7 side chain, the compounds 1m and 1p±
1r bearing a 5-amino-1,2,4-thiadiazole group showed
similar or superior antibacterial activities to those of the
compounds 2m and 2p±2r bearing a 2-aminothiazole
group against MRSA and Gram-negative bacteria,
including P. aeruginosa. On the other hand, the com-
pounds 1m and 1p±1r bearing a 5-amino-1,2,4-thiadia-
zole group showed inferior antibacterial activities to
those of the compounds 2m and 2p±2r bearing a 2-ami-

M. Tsushima et al. / Bioorg. Med. Chem. 8 (2000) 2781±2789
2783
Figure 1. CP6679 (1s) and related compounds.

2784
M. Tsushima et al. / Bioorg. Med. Chem. 8 (2000) 2781±2789
Table 1. Antibacterial activities of 1a±1g (MIC; mg/mL)
Test organism
1a
1b
1c
1d
1e
1f
1g
Staphylococcus aureus 209P JC-1
S. aureus M133a
0.39
6.25
12.5
0.39
25
<0.025
<0.025
0.10
0.39
6.25
12.5
0.39
12.5
<0.025
<0.025
0.10
0.39
0.39
6.25
12.5
0.39
12.5
<0.025
<0.025
0.20
0.39
6.25
12.5
0.39
6.25
<0.025
<0.025
0.20
0.78
6.25
25
0.39
25
<0.025
<0.025
0.20
0.78
6.25
12.5
0.78
12.5
<0.025
<0.025
0.20
12.5
25
0.39
S. aureus M126a
S. epidermidis ATCC14990
Enterococcus hirae ATCC8043
Escherichia coli NIHJ JC-2
Klebsiella pneumoniae PCI602
E. coli 255
25
<0.025
<0.025
0.10
E. coli GN206
0.05
0.20
3.13
1.56
<0.025
3.13
0.10
0.05
0.20
3.13
1.56
<0.025
3.13
0.10
0.05
0.39
12.5
0.05
0.20
3.13
3.13
<0.025
3.13
0.10
0.05
0.20
3.13
3.13
<0.025
3.13
0.10
0.05
0.39
12.5
0.05
0.78
12.5
Proteus vulgaris GN76
P. vulgaris GN76/C-1
Morganella morganii 1510
M. morganii 1510/S-1
Citrobacter freundii GN346
C. freundii GN346/16
1.56
3.13
3.13
<0.025
6.25
0.10
<0.025
12.5
0.20
<0.025
6.25
0.10
Enterobacter cloacae G-0008
Serratia marcescens No.1
Pseudomonas aeruginosa GN10362
P. aeruginosa E-2
<0.025
<0.025
0.78
<0.025
<0.025
0.78
<0.025
<0.025
1.56
<0.025
<0.025
0.78
<0.025
<0.025
0.78
0.05
0.05
1.56
1.56
0.05
0.05
1.56
1.56
0.78
0.78
0.78
0.78
0.78
aThese strains are MRSA.
Table 2. Antibacterial activities of 1h±1o (MIC; mg/mL)
Test organism
1h
1i
1j
1k
1l
1m
1n
1o
S. aureus 209P JC-1
S. aureus M133a
0.78
6.25
6.25
0.39
1.56
0.20
0.20
0.20
0.10
0.78
0.39
6.25
12.5
0.39
25
0.05
0.05
0.20
0.05
0.39
1.56
12.5
12.5
1.56
3.13
0.20
0.39
0.39
0.10
1.56
0.78
6.25
12.5
0.78
12.5
0.10
0.10
0.39
0.10
0.78
12.5
3.13
0.05
6.25
0.20
0.10
0.10
3.13
3.13
0.78
3.13
6.25
0.78
3.13
0.10
0.10
0.20
0.05
1.56
12.5
1.56
0.05
3.13
0.10
0.20
0.20
3.13
3.13
0.78
3.13
6.25
0.78
3.13
0.05
0.05
0.20
0.78
6.25
12.5
1.56
3.13
0.10
0.10
0.10
<0.025
1.56
12.5
0.39
0.05
0.78
0.10
0.20
0.10
3.13
3.13
0.78
12.5
25
S. aureus M126a
S. epidermidis ATCC14990
E. hirae ATCC8043
E. coli NIHJ JC-2
K. pneumoniae PCI602
E. coli 255
1.56
1.56
0.05
0.10
0.10
<0.025
0.78
12.5
0.39
<0.025
1.56
0.05
0.10
0.05
3.13
3.13
E. coli GN206
P. vulgaris GN76
<0.025
0.78
6.25
P. vulgaris GN76/C-1
M. morganii 1510
M. morganii 1510/S-1
C. freundii GN346
C. freundii GN346/16
E. cloacae G-0008
S. marcescens No.1
P. aeruginosa GN10362
P. aeruginosa E-2
12.5
12.5
6.25
0.05
25
3.13
0.10
6.25
0.20
0.20
0.10
3.13
3.13
6.25
0.20
6.25
0.39
0.39
0.20
6.25
6.25
0.39
<0.025
1.56
0.05
0.10
0.10
12.5
0.20
0.05
0.05
1.56
1.56
1.56
1.56
aThese strains are MRSA.
the compounds bearing methyl and hydroxymethyl
groups. Overall, 1s had the highest potency against all
the tested bacteria, including MRSA and P. aeruginosa.
Gemini 300 NMR spectrometer for 300 MHz in CDCl3,
DMSO-d6, or D2O. TMS (0 ppm) in CDCl3 and
DMSO-d6 or HDO (4.8 ppm) in D2O was used as inter-
nal reference standard. IR spectra were recorded on a
Shimadzu FT-IR 8100 spectrometer as KBr pellets.
Mass spectra were obtained on a JEOL JMS-700 mass
spectrometer for FABMS and FABHRMS. Silica gel
¯ash column chromatography was performed on Wako-
gel C-300 (Wako Chemical).
Compound 1s was compared with clinically used inject-
able cephalosporins (Table 5). It showed a similar or
superior antibacterial activity to ceftazidime,8 cefpir-
ome,7 cefozopran3 and cefoselis,4 and had the strongest
activity among these cephalosporins against MRSA and
P. aeruginosa. Further evaluation of compound 1s as a
candidate drug is in progress.
Antibacterial activity in vitro
Minimum inhibitory concentration (MIC) was deter-
mined by the agar plate dilution method. Test strains
were subjected to seed culture using Sensitivity test
broth (STB, Nissui Pharmaceutical). A 5 mL portion of
cell suspension of test strains having about 106 cfu/mL
was inoculated and incubated at 37 ꢀC for 20 h. The
MIC was then measured.
Experimental
General methods
1H NMR spectra were measured with a JEOL JNM-
GSX 400 NMR spectrometer for 400 MHz or a Varian

M. Tsushima et al. / Bioorg. Med. Chem. 8 (2000) 2781±2789
Table 3. Antibacterial activities of 1m, 1p±1r, 2m and 2p±2r (MIC; mg/mL)
2785
Test organism
1p
1m
1q
1r
2p
2m
2q
2r
S. aureus 209P JC-1
S. aureus M133a
0.78
6.25
12.5
0.78
3.13
0.05
0.05
0.78
3.13
6.25
0.78
3.13
0.05
0.05
0.20
0.78
6.25
12.5
0.39
3.13
<0.025
<0.025
0.05
<0.025
0.39
6.25
0.20
<0.025
0.78
<0.025
<0.025
<0.025
0.78
1.56
6.25
12.5
0.39
6.25
25
0.39
3.13
0.05
0.05
0.78
6.25
25
0.78
12.5
0.78
0.78
6.25
25
0.78
12.5
0.10
0.10
0.20
0.05
0.78
3.13
0.39
<0.025
3.13
0.20
0.20
0.20
12.5
25
0.39
6.25
0.05
0.05
0.10
<0.025
0.10
1.56
S. aureus M126a
S. epidermidis ATCC14990
E. hirae ATCC8043
E. coli NIHJ JC-2
K. pneumoniae PCI602
E. coli 255
1.56
6.25
0.05
0.05
0.20
<0.025
0.78
12.5
0.78
0.05
1.56
0.10
0.10
0.10
3.13
3.13
0.20
0.20
0.39
0.05
0.78
3.13
0.39
0.05
3.13
0.39
0.39
0.20
6.25
6.25
0.05
0.10
E. coli GN206
P. vulgaris GN76
<0.025
0.78
25
<0.025
0.78
6.25
<0.025
0.20
3.13
P. vulgaris GN76/C-1
M. morganii 1510
M. morganii 1510/S-1
C. freundii GN346
C. freundii GN346/16
E. cloacae G-0008
S. marcescens No.1
P. aeruginosa GN10362
P. aeruginosa E-2
0.39
0.39
0.20
0.10
<0.025
0.78
0.05
0.05
0.05
<0.025
1.56
0.05
0.10
0.10
<0.025
3.13
0.10
0.10
0.05
<0.025
3.13
0.10
0.10
0.05
1.56
1.56
1.56
1.56
6.25
6.25
6.25
6.25
6.25
6.25
1.56
aThese strains are MRSA.
Table 4. Antibacterial activities of 1q and 1s±1w (MIC; mg/mL)
Test organism
1q
1s
1t
1u
1v
1w
S. aureus 209P JC-1
S. aureus M133a
0.78
6.25
12.5
0.39
3.13
<0.025
<0.025
0.05
<0.025
0.39
6.25
0.20
<0.025
0.78
<0.025
<0.025
<0.025
0.78
0.78
6.25
6.25
1.56
0.78
6.25
12.5
1.56
1.56
0.05
0.10
0.20
<0.025
0.78
25
0.20
0.05
0.78
0.10
0.20
0.10
3.13
1.56
0.78
6.25
6.25
0.78
1.56
<0.025
<0.025
0.05
<0.025
0.39
12.5
0.20
<0.025
0.78
0.78
6.25
12.5
1.56
12.5
25
S. aureus M126a
S. epidermidis ATCC14990
E. hirae ATCC8043
E. coli NIHJ JC-2
K. pneumoniae PCI602
E. coli 255
1.56
1.56
0.10
0.10
0.20
<0.025
1.56
50
0.20
0.05
6.25
0.10
0.20
0.10
3.13
3.13
1.56
12.5
0.78
0.78
1.56
0.20
6.25
50
3.13
0.39
12.5
0.78
1.56
0.39
6.25
6.25
1.56
<0.025
0.05
0.05
<0.025
0.39
12.5
E. coli GN206
P. vulgaris GN76
P. vulgaris GN76/C-1
M. morganii 1510
M. morganii 1510/S-1
C. freundii GN346
C. freundii GN346/16
E. cloacae G-0008
S. marcescens No.1
P. aeruginosa GN10362
P. aeruginosa E-2
0.20
<0.025
0.39
0.05
0.05
0.05
<0.025
0.05
<0.025
0.78
0.78
0.78
0.78
1.56
aThese strains are MRSA.
2-[(N-tert-Butoxycarbonyl-D-alanyl)amino]methylthiazole
(4). To a suspended solution of 3 (946 mg, 5.00 mmol)
and 1-hydroxybenzotriazole (743 mg, 5.50 mmol) in dry
CH2Cl2 (10 mL) was added 2-aminomethylthiazole11
(628mg, 5.50mmol) at 0 ꢀC. Then, to the reaction mixture
was added dicyclohexylcarbodiimide (1.135g, 5.50 mmol)
at 0 ꢀC, and the mixture was stirred at room temperature
for 1 h. After ®ltration of insoluble, the ®ltrate was washed
with 5% aqueous NaHCO3 (5mL), dried over MgSO4
and concentrated under reduced pressure. The residue was
puri®ed by silica gel ¯ash column chromatography to give
CH2Cl2 (20 mL) was added 4N aqueous HCl (10 mL) at
0 ꢀC, and the mixture was stirred at room temperature
for 19 h. After separation of the organic layer, the aqu-
eous layer was adjusted at pH > 14 by the adding 40%
aqueous KOH and extracted with CH2Cl2 (10 mL)
twice. To the aqueous layer was added K2CO3 (8 g), and
it was extracted with CH2Cl2 (10 mL) twice. The com-
bined organic layer was dried over K2CO3 and con-
centrated under reduced pressure to give 2-(d-alanyl-
aminomethyl)thiazole.
1
4 (1.425g, 5.00mmol, 100%) : H NMR (CDCl3) d 1.39
To a solution of 2-(d-alanylaminomethyl)thiazole in
CH2Cl2 (1 mL) were added triethylamine (1.4 mL, 10.0
mmol) and ethyl tri¯uoroacetate (1.2 mL, 10.0 mmol) at
0 ꢀC, and the mixture was stirred at room temperature
for 1 h. To the reaction mixture was added diisopropyl-
ether (2 mL), and then the reaction mixture was ®ltrated
at 10 ꢀC to collect 2-[(N-tri¯uoroacetyl-d-alanyl)ami-
no]methylthiazole (1.405 g, 5.00 mmol, 100%): 1H
(3H, d, J=7 Hz), 1.43 (9H, s), 4.15±4.30 (1H, m), 4.76
(1H, dd, J=6 Hz, 12Hz), 4.77 (1H, dd, J=6Hz, 12Hz),
4.90±5.10 (1H, m), 6.95±7.15 (1H, m), 7.28 (1H, d,
J=3Hz), 7.70 (1H, d, J=3Hz).
5-[(R)-1-(Tri¯uoroacetylamino)ethyl]imidazo[5,1-b]thia-
zole (5). To a solution of 4 (1.425 g, 5.00 mmol) in

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M. Tsushima et al. / Bioorg. Med. Chem. 8 (2000) 2781±2789
Table 5. Antibacterial activities of 1s and clinically used cephalosporins (MIC; mg/mL).
Test organism
1s
Ceftazidime
Cefpirome
Cefozopran
Cefoselis
S. aureus 209P JC-1
S. aureus M133a
0.78
6.25
6.25
1.56
3.13
100
0.39
25
100
0.39
12.5
50
0.39
50
0.39
12.5
25
S. aureus M126a
>100
3.13
>100
0.20
0.10
12.5
1.56
0.10
0.10
12.5
0.10
25
S. epidermidis ATCC14990
E. hirae ATCC8043
E. coli NIHJ JC-2
K. pneumoniae PCI602
E. coli 255
0.39
3.13
0.05
0.05
0.20
<0.025
0.39
3.13
0.20
<0.025
0.78
0.10
0.05
0.05
3.13
3.13
0.39
6.25
0.10
0.10
0.39
0.05
0.20
0.78
0.39
<0.025
3.13
0.10
0.10
0.05
3.13
3.13
1.56
<0.025
0.05
0.05
<0.025
0.39
12.5
0.05
0.05
0.20
0.05
0.39
6.25
3.13
0.10
1.56
0.05
0.10
0.10
0.78
0.78
E. coli GN206
P. vulgaris GN76
P. vulgaris GN76/C-1
M. morganii 1510
M. morganii 1510/S-1
C. freundii GN346
C. freundii GN346/16
E. cloacae G-0008
S. marcescens No.1
P. aeruginosa GN10362
P. aeruginosa E-2
0.20
<0.025
0.39
0.05
0.05
0.05
0.78
0.20
0.05
1.56
1.56
0.78
0.78
aThese strains are MRSA.
NMR (CDCl3) d 1.51 (3H, d, J=7 Hz), 4.57 (1H, quin-
tet, J=7 Hz), 4.77 (1H, dd, J=6 Hz, 16 Hz), 4.78 (1H,
dd, J=6 Hz, 16 Hz), 6.90±7.10 (1H, m), 7.33 (1H, d,
J=3 Hz), 7.35±7.55 (1H, m), 7.73 (1H, d, J=3 Hz).
1 h. The reaction mixture was extracted with water (10 mL)
twice, and the combined aqueous layer was adjusted to pH
10 with K2CO3. The aqueous layer was extracted with
CH2Cl2 (20 mL) three times, and the combined organic
layer was dried over MgSO4 and concentrated under
reduced pressure. The residue was recrystallized from ethyl
To a suspended solution of 2-[(N-tri¯uoroacetyl-d-ala-
nyl)amino]methylthiazole (1.405 g, 5.00 mmol) in tolu-
ene (5.1 mL) was added phosphorus oxychloride
(5.1 mL), and the mixture was stirred at 120 ꢀC for 3 h.
After being cooled, the reaction mixture was con-
centrated under reduced pressure, and was added with
CH2Cl2 (5 mL) and water (10 mL). The organic layer
was separated and extracted with water (5 mL). The
combined aqueous layer was adjusted to pH 7 with 30%
aqueous K2CO3, and extracted with CH2Cl2 (10 mL)
twice. The combined organic layer was dried over
MgSO4 and concentrated under reduced pressure. The
residue was puri®ed by silica gel ¯ash column chroma-
tography to give 5 (1.165 g, 4.43 mmol, 89% from 4): 1H
NMR (CDCl3) d 1.63 (0.3H, d, J=7 Hz), 1.74 (2.7H, d,
J= 7 Hz), 5.43±5.75 (1H, m), 6.87 (1H, d, J=4 Hz),
6.98 (0.9H, s), 7.01 (0.1H, s), 7.51 (0.9H, d, J=4 Hz),
7.64 (0.1H, d, J=4 Hz), 7.55±7.75 (1H, m).
1
acetate to give 6 (839mg, 4.30 mmol, 97%): H NMR
(CDCl3) d 1.70 (3H, d, J=7 Hz), 5.61 (1H, q, J=7 Hz),
6.40±6.55 (1H, m), 6.81 (1H, d, J=4 Hz), 6.97 (1H, s),
7.59 (1H, d, J=4 Hz), 8.19 (1H, s).
(6R,7R)-7-[(Z)-2-(5-Amino-1,2,4-thiadiazol-3-yl)-2-(¯uoro-
methoxyimino)acetamido] - 3 - [5 - [(R) - 1 - (formylamino)-
ethyl]imidazo[5,1-b]thiazolium-6-yl]methyl-3-cephem-4-
carboxylate (1s, CP6679). To a suspended solution of 2
-(5-amino-1,2,4-thiadiazol-3-yl)-(Z)-2-¯uoromethoxy-
iminoacetic acid (511 mg, 2.32 mmol) in dry CH2Cl2
(5 mL) was added phosphorous pentachloride (569 mg,
2.73 mmol) at 20 ꢀC, and the mixture was stirred at
15 ꢀC for 2.5 h to a€ord the acid chloride solution. To a
suspended solution of 7 (1.23 g, 2.27 mmol) in dry CH2Cl2
(17.5 mL) were added N,O-bis(trimethy-lsilyl)acetamide
(5 mL, 20 mmol) at room temperature, then above acid
chloride solution at 20 ꢀC, and the mixture was stirred
at 20ꢀC for 1 h. After addition of water (50 mL), the
mixture was stirred at room temperature for 30 min, and
extracted with ethyl acetate (100 mL). The organic layer
was washed with saturated aqueous NaHCO3 (100 mL)
and saturated aqueous NaCl (100 mL), dried over MgSO4
and concentrated under reduced pressure. The residue
was puri®ed by silica gel ¯ash column chromatography to
give 8 (1.10 g, 1.93 mmol, 85%): 1H NMR (CDCl3) d 3.47
(1H, d, J= 18 Hz), 3.67 (1H, d, J=18 Hz), 3.81 (3H, s),
4.34 (1H, d, J=12 Hz), 4.62 (1H, d, J=12 Hz), 5.09 (1H,
d, J=5 Hz), 5.22 (2H, s), 5.73 (1H, dd, J=54Hz, 3 Hz),
5.86 (1H, dd, J=54 Hz, 3 Hz), 6.11 (1H, dd, J=5 Hz,
9 Hz), 6.55 (2H, s), 6.89 (2H, d, J=9 Hz), 7.32 (2H, d,
J=9 Hz), 8.28 (1H, d, J=9Hz).
5-[(R)-1-(Formylamino)ethyl]imidazo[5,1-b]thiazole (6).
To a solution of 5 (1.165 g, 4.43 mmol) in MeOH
(20 mL) was added 12.7% aqueous KOH (20 mL) at
5 ꢀC, and the mixture was stirred at room temperature
for 1 h. After MeOH was removed from the reaction
mixture under reduced pressure, the aqueous layer was
extracted with CH2Cl2 (20 mL). To the aqueous layer
was added K2CO3 (10 g), and the aqueous layer was
extracted again with CH2Cl2 (10 mL) twice. The com-
bined organic layer was dried over K2CO3 and con-
centrated under reduced pressure to give 5-[(R)-1-
aminoethyl]imidazo[5,1-b]thiazole.
To a solution of 5 - [(R) - 1 - aminoethyl]imidazo[5,1 - b]
thiazole in CH2Cl2 (20 mL) was added a mixture of
formic acid (0.9 mL) and acetic anhydride (1.8 mL) stir-
red at 50 ꢀC for 15 min, then at room temperature for
To a solution of 8 (651mg, 0.800 mmol) in acetone (7 mL)
was added sodium iodide (150mg, 1.00mmol), and the

M. Tsushima et al. / Bioorg. Med. Chem. 8 (2000) 2781±2789
2787
mixture was stirred at room temperature for 1.5 h. After
addition of water (10 mL), the mixture was extracted with
CH2Cl2 (10 mLÂ2). The combined organic layer was
washed with 5% aqueous Na2S2O3 (20 mL), dried over
MgSO4 and concentrated under reduced pressure to a€ord
3-iodomethylcephem compound.
d, J=55 Hz), 5.87 (1H, d, J=5 Hz), 7.88 (1H, s), 8.36
1
(1H, s), 8.97 (1H, s); IR (KBr) cm
FABMS m/z 582 [(M+H)+]; FABHRMS calcd for
1770 (CˆO);
C19H17FN9O6S3 [(M+H)+]: 582.0448, found: 582.0436.
Compound 1c was obtained in 28% yield from com-
pound 7: 1H NMR (D2O) d 3.24 (1H, d, J=18 Hz), 3.65
(1H, d, J=18 Hz), 4.86 (2H, s), 5.15 (1H, d, J=15 Hz),
5.27 (1H, d, J=5 Hz), 5.31 (1H, d, J=15 Hz), 5.82 (2H,
To a solution of 3-iodomethylcephem compound in
DMF (7 mL) was added 6 (195 mg, 1.00 mmol), and the
mixture was stirred at room temperature for 18 h. After
addition of saturated aqueous NaCl (50 mL), the mix-
ture was extracted with ethyl acetate (20 mLÂ2). The
combined organic layer was washed with saturated
aqueous NaCl (20 mL), dried over MgSO4 and con-
centrated under reduced pressure. To the solution of the
residue in DMF (2 mL) was added 2N aqueous
CF3COONa (20 mL), and the mixture was stirred at
room temperature for 30 min. The mixture was ®ltrated
to collect the precipitate 9: 1H NMR (DMSO-d6) d 1.55
(3H, d, J=7 Hz), 3.44 (1H, d, J=18 Hz), 3.52 (1H, d,
J=18 Hz), 3.74 (3H, s), 5.10±5.55 (6H, m), 5.75 (2H, d,
J=54 Hz), 5.93 (1H, dd, J=5 Hz, 9 Hz), 6.89 (2H, d,
J=9 Hz), 7.33 (2H, d, J=9 Hz), 7.65 (1H, s), 7.86 (1H,
d, J=4 Hz), 7.94 (1H, s), 8.08 (1H, s), 8.20 (2H, s), 8.26
(1H, d, J=4 Hz), 9.31 (1H, d, J=9 Hz).
d, J=55 Hz), 5.88 (1H, d, J=5 Hz), 7.46 (1H, s), 7.80
1
(1H, s), 9.42 (1H, s); IR (KBr) cm
FABMS m/z 569 [(M+H)+]; FABHRMS calcd for
1770 (CˆO);
C19H18FN8O6S3 [(M+H)+]: 569.0495, found: 569.0510.
Compound 1d was obtained in 39% yield from com-
pound 7: 1H NMR (D2O) d 3.26 (1H, d, J=18 Hz), 3.66
(1H, d, J=18 Hz), 4.50±4.72 (3H, m), 4.84±4.88 (1H,
m), 5.16 (1H, d, J=15 Hz), 5.29 (1H, d, J=5 Hz), 5.32
(1H, d, J=15 Hz), 5.89 (1H, d, J=5 Hz), 7.56 (1H, d,
J=4 Hz), 7.79 (1H, s), 7.95 (1H, d, J=4 Hz), 9.38 (1H,
1
s); IR (KBr) cm
[(M+H)+]; FABHRMS calcd for C19H18FN8O5S3
[(M+H)+]: 553.0546, found: 553.0551.
1770 (CˆO); FABMS m/z 553
Compound 1e was obtained in 20% yield from com-
pound 7: 1H NMR (D2O) d 3.24 (1H, d, J=18 Hz), 3.63
(1H, d, J=18 Hz), 4.49 (1H, m), 4.59 (1H, m), 4.68 (1H,
m), 4.84 (1H, m), 5.18 (1H, d, J=14 Hz), 5.27 (1H, d,
J=5 Hz), 5.33 (1H, d, J=14 Hz), 5.87 (1H, d, J=5 Hz),
To a solution of 9 in anisole (3.5 mL) was added tri-
¯uoroacetic acid (7 mL) at 0 ꢀC, and the mixture was
stirred at the same temperature for 1 h. The mixture was
poured into diisopropyl ether (35 mL) under ice cooling.
The precipitate were collected by ®ltration. The suspen-
sion of the precipitate in water (3 mL) was adjusted to
pH 8.0 with saturated aqueous NaHCO3 and puri®ed
by Diaion HP-20 (Mitsubishi Chemical) column chro-
matography (50 mL) to a€ord 1s (118 mg, 0.193 mmol,
24%): 1H NMR (D2O) d 1.69 (3H, d, J=7 Hz), 3.23 (1H,
d, J=18 Hz), 3.49 (1H, d, J=18 Hz), 5.25 (1H, d,
J=5 Hz), 5.32 (1H, d, J=15 Hz), 5.49 (1H, d, J=15 Hz),
5.58 (1H, q, J=7 Hz), 5.82 (2H, d, J=54 Hz), 5.88 (1H,
1
7.88 (1H, s), 8.37 (1H, s), 9.78 (1H, s); IR (KBr) cm
1770 (CˆO); FABMS m/z 596 [(M+H)+]; FABHRMS
calcd for C20H19FN9O6S3 [(M+H)+]: 596.0604, found:
596.0608.
Compound 1f was obtained in 34% yield from com-
pound 7: 1H NMR (D2O) d 3.23 (1H, d, J=18 Hz), 3.63
(1H, d, J=18 Hz), 4.49 (1H, m), 4.58 (1H, m), 4.61 (1H,
m), 4.79 (1H, m), 4.88 (2H, s), 5.16 (1H, d, J=15 Hz),
5.27 (1H, d, J=5 Hz), 5.30 (1H, d, J=15 Hz), 5.87 (1H,
d, J=5 Hz), 7.47 (1H, s), 7.79 (1H, s), 9.42 (1H, s); IR
d, J=5 Hz), 7.58 (1H, d, J=4 Hz), 7.69 (1H, s), 7.97
1
1
(1H, d, J=4 Hz), 8.11 (1H, s); IR (KBr) cm
1770
(KBr) cm 1770 (CˆO); FABMS m/z 583 [(M+H)+];
(CˆO); FABMS m/z 610 [(M+H)+]; FABHRMS
calcd for C21H21FN9O6S3 [(M+H)+]: 610.0761, found:
610.0753.
FABHRMS calcd for C20H20FN8O6S3 [(M+H)+]:
583.0652, found: 583.0652.
Compound 1g was obtained in 31% yield from com-
pound 7: 1H NMR (D2O) d 3.24 (1H, d, J=18 Hz), 3.64
(1H, d, J=18 Hz), 4.50 (1H, m), 4.59 (1H, m), 4.69 (1H,
m), 4.84 (1H, m), 5.18 (1H, d, J=15 Hz), 5.27 (1H, d,
J=5 Hz), 5.33 (1H, d, J=15 Hz), 5.69 (2H, d,
J=48 Hz), 5.88 (1H, d, J=5 Hz), 7.77 (1H, s), 7.84 (1H,
s), 9.55 (1H, s); IR (KBr) cm 1 1770 (CˆO); FABMS m/z
585 [(M+H)+]; FABHRMS calcd for C20H19F2
N8O5S3 [(M+H)+]: 585.0609, found: 585.0595.
Compounds 1a±1r, 1t±1w, 2m and 2p±2r. These com-
pounds were prepared by a similar procedure as descri-
bed for the preparation of 1s.
Compound 1a was obtained in 34% yield from com-
pound 7: 1H NMR (D2O) d 3.24 (1H, d, J=18 Hz), 3.64
(1H, d, J=18 Hz), 5.15 (1H, d, J=14 Hz), 5.28 (1H, d,
J=5 Hz), 5.30 (1H, d, J=14 Hz), 5.84 (2H, d, J=
54 Hz), 5.90 (1H, d, J=5 Hz), 7.54 (1H, d, J=4 Hz),
7.77 (1H, s), 7.93 (1H, d, J=4 Hz), 9.37 (1H, s); IR
Compound 1h was obtained in 1.8% yield from com-
1
1
(KBr) cm 1770 (CˆO); FABMS m/z 539 [(M+H)+];
pound 7: H NMR (D2O) d 1.29 (3H, t, J=7 Hz), 3.27
FABHRMS calcd for C18H16FN8O5S3 [(M+H)+]:
539.0390, found: 539.0411.
(1H, d, J=18 Hz), 3.55 (1H, d, J=18 Hz), 4.31 (2H, q,
J=7 Hz), 5.24 (1H, d, J=5 Hz), 5.42 (1H, d, J=15 Hz),
5.59 (1H, d, J=15 Hz), 5.86 (1H, d, J=5 Hz), 7.73 (1H,
d, J=4 Hz), 8.02 (1H, s), 8.18 (1H, d, J=4 Hz); IR
Compound 1b was obtained in 28% yield from com-
1
1
pound 7: H NMR (D2O, pD=1) d 3.23 (1H, d, J=
18 Hz), 3.64 (1H, d, J=18 Hz), 5.15 (1H, d, J=15 Hz),
5.27 (1H, d, J=5 Hz), 5.33 (1H, d, J=15 Hz), 5.81 (2H,
(KBr) cm 1770 (CˆO); FABMS m/z 578 [(M+H)+];
FABHRMS calcd for C20H20N9O6S3 [(M+H)+]:
570.0699, found: 578.0710.

2788
M. Tsushima et al. / Bioorg. Med. Chem. 8 (2000) 2781±2789
Compound 1i was obtained in 19% yield from com-
1
Compound 1o was obtained in 23% yield from com-
1
pound 7: H NMR (DMSO-d6) d 1.21 (3H, t, J=7 Hz),
pound 7: H NMR (D2O) d 1.33 (3H, t, J=7 Hz), 2.02
3.11 (1H, d, J=18 Hz), 3.64 (1H, d, J=18 Hz), 4.12
(2H, q, J=7 Hz), 4.88 (1H, d, J=15 Hz), 5.00 (1H, d,
J=5 Hz), 5.36 (1H, d, J=15 Hz), 5.64 (1H, dd, J=8 Hz,
5 Hz), 7.67 (1H, d, J=4 Hz), 8.11 (2H, s), 8.21 (2H, m),
(3H, s), 3.15 (1H, d, J=18 Hz), 3.59 (1H, d, J=18 Hz),
4.35 (2H, q, J=7 Hz), 4.94 (1H, s), 4.95 (1H, s), 5.28
(1H, d, J=15 Hz), 5.29 (1H, d, J=5 Hz), 5.36 (1H, d,
J=15 Hz), 5.88 (1H, d, J=5 Hz), 7.59 (1H, d, J=4 Hz),
1
1
9.42 (1H, d, J=8 Hz), 9.79 (1H, s); IR (KBr) cm 1770
(CˆO); FABMS m/z 563 [(M+H)+]; FABHRMS calcd
7.74 (1H, s), 8.04 (1H, d, J=4 Hz); IR (KBr) cm 1770
(CˆO); FABMS m/z 606 [(M+H)+]; FABHRMS calcd
for C20H19N8O6S3 [(M+H)+]: 563.0590, found: 563.0594.
for C22H24N9O6S3 [(M+H)+]: 606.1012, found: 606.0999.
Compound 1j was obtained in 2.5% yield from com-
1
Compound 1p was obtained in 13% yield from com-
pound 7: 1H NMR (D2O) d 3.15 (1H, d, J=18 Hz), 3.58
(1H, d, J=18 Hz), 4.05 (3H, s), 5.02 (2H, s), 5.27 (1H, d,
J=5 Hz), 5.28 (1H, d, J=15 Hz), 5.33 (1H, d, J=
15 Hz), 5.86 (1H, d, J=5 Hz), 7.58 (1H, d, J=4 Hz),
7.73 (1H, s), 8.03 (1H, d, J=4 Hz), 8.20 (1H, s); IR
pound 7: H NMR (D2O) d 1.33 (3H, t, J=7 Hz), 3.34
(1H, d, J=18 Hz), 3.69 (1H, d, J=18 Hz), 4.36 (2H, q,
J=7 Hz), 5.31 (1H, d, J=5 Hz), 5.45 (1H, d, J=15 Hz),
5.56 (1H, d, J=15 Hz), 5.91 (1H, d, J=5 Hz), 8.04 (1H,
d, J=4 Hz), 8.30 (1H, s), 8.37 (1H, d, J=4 Hz); IR
1
1
(KBr) cm 1770 (CˆO); FABMS m/z 560 [(M+H)+];
(KBr) cm 1770 (CˆO); FABMS m/z 578 [(M+H)+];
FABHRMS calcd for C20H18N9O5S3 [(M+H)+]:
560.0593, found: 560.0591.
FABHRMS calcd for C20H20N9O6S3 [(M+H)+]:
578.0699, found: 578.0695.
Compound 1k was obtained in 14% yield from com-
1
Compound 1q was obtained in 15% yield from com-
pound 7: 1H NMR (D2O) d 3.16 (1H, d, J=18 Hz), 3.60
(1H, d, J=18 Hz), 5.03 (2H, s), 5.20 (1H, d, J=15 Hz),
5.32 (1H, d, J=5 Hz), 5.36 (1H, d, J=15 Hz), 5.90 (2H,
d, J=57 Hz), 5.84 (1H, d, J=5Hz), 7.60 (1H, d, J=4Hz),
7.73 (1H, s), 8.05 (1H, d, J=4Hz), 8.21 (1H, s); IR
pound 7: H NMR (D2O) d 1.34 (3H, t, J=7 Hz), 3.25
(1H, d, J=18 Hz), 3.57 (1H, d, J=18 Hz), 4.36 (2H, q,
J=7 Hz), 5.22 (2H, s), 5.28 (1H, d, J=15 Hz), 5.28 (1H,
d, J=5 Hz), 5.36 (1H, d, J=15 Hz), 5.89 (1H, d,
J=5 Hz), 7.60 (1H, d, J=4 Hz), 7.78 (1H, s), 8.07 (1H,
1
1
d, J=4 Hz); IR (KBr) cm 1770 (CˆO); FABMS m/z
(KBr) cm 1770 (CˆO); FABMS m/z 596 [(M+H)+];
565 [(M+H)+]; FABHRMS calcd for C20H21N8O6S3
[(M+H)+]: 565.0746, found: 565.0743.
FABHRMS calcd for C20H19FN9O6S3 [(M+H)+]:
596.0604, found: 596.0608.
Compound 1l was obtained in 27% yield from com-
1
Compound 1r was obtained in 17% yield from com-
pound 7: 1H NMR (D2O) d 3.17 (1H, d, J=18 Hz), 3.60
(1H, d, J=18 Hz), 4.50±4.75 (3H, m), 4.85±4.90 (1H,
m), 5.04 (2H, s), 5.30 (1H, d, J=5 Hz), 5.30 (1H, d,
J=15 Hz), 5.38 (1H, d, J=15 Hz), 5.89 (1H, d,
J=5 Hz), 7.61 (1H, d, J=4 Hz), 7.75 (1H, s), 8.06 (1H,
pound 7: H NMR (D2O) d 1.33 (3H, t, J=7 Hz), 3.23
(1H, d, J=18 Hz), 3.50 (3H, s), 3.53 (1H, d, J=18 Hz),
4.36 (2H, q, J=7 Hz), 5.11 (2H, s), 5.29 (1H, d, J=
15 Hz), 5.26 (1H, d, J=5 Hz), 5.31 (1H, d, J=15 Hz),
5.89 (1H, d, J=5 Hz), 7.63 (1H, d, J=6 Hz), 7.84 (1H,
1
1
s), 8.06 (1H, d, J=6 Hz); IR (KBr) cm 1770 (CˆO);
d, J=4 Hz), 8.22 (1H, s); IR (KBr) cm 1770 (CˆO);
FABMS m/z 579 [(M+H)+]; FABHRMS calcd for
FABMS m/z 610 [(M+H)+]; FABHRMS calcd for
C21H23N8O6S3 [(M+H)+]: 579.0903, found: 579.0903.
C21H21FN9O6S3 [(M+H)+]: 610.0761, found: 610.0753.
Compound 1m was obtained in 29% yield from com-
1
Compound 1t was obtained in 34% yield from com-
1
pound 7: H NMR (D2O) d 1.31 (3H, t, J=7 Hz), 3.16
pound 7: H NMR (D2O) d 1.68 (3H, d, J=7 Hz), 3.23
(1H, d, J=18 Hz), 3.58 (1H, d, J=18 Hz), 4.34 (2H, q,
J=7 Hz), 5.03 (2H, s), 5.28 (1H, d, J=5 Hz), 5.29 (1H,
d, J=15 Hz), 5.34 (1H, d, J=15 Hz), 5.87 (1H, d,
J=5 Hz), 7.59 (1H, d, J=4 Hz), 7.73 (1H, s), 8.04 (1H,
(1H, d, J=18 Hz), 3.59 (1H, d, J=18 Hz), 5.27 (1H, d,
J=5 Hz), 5.30 (1H, d, J=15 Hz), 5.34 (1H, br-s), 5.64
(1H, q, J=7 Hz), 5.83 (2H, d, J=54 Hz), 5.87 (1H, d,
J=5 Hz), 7.59 (1H, d, J=4 Hz), 7.72 (1H, s), 7.97 (1H,
1
1
d, J=4 Hz), 8.20 (1H, s); IR (KBr) cm 1770 (CˆO);
d, J=4 Hz), 8.14 (1H, s); IR (KBr) cm 1770 (CˆO);
FABMS m/z 592 [(M+H)+]; FABHRMS calcd for
FABMS m/z 610 [(M+H)+]; FABHRMS calcd for
C21H22N9O6S3 [(M+H)+]: 592.0855, found: 592.0853.
C21H21FN9O6S3 [(M+H)+]: 610.0767, found: 610.0753.
Compound 1n was obtained in 15% yield from com-
1
Compound 1u was obtained in 26% yield from com-
pound 7: 1H NMR (D2O) d 3.13 (1H, d, J=18 Hz), 3.48
(1H, d, J=18 Hz), 3.98±4.00 (2H, m), 5.17 (1H, d,
J=5 Hz), 5.24 (1H, d, J=15 Hz), 5.30 (1H, d, J=
15 Hz), 5.59 (1H, t, J=5 Hz), 5.63 (1H, s), 5.77 (1H, d,
J=5 Hz), 5.81 (1H, s), 7.47 (1H, d, J=4 Hz), 7.71 (1H,
pound 7: H NMR (D2O) d 1.32 (3H, t, J=7Hz), 2.81
(0.75H, s), 3.08 (2.25H, s), 3.14 (0.25H, d, J=18 Hz), 3.16
(0.75H, d, J=18 Hz), 3.57 (0.25H, d, J=18 Hz), 3.60
(0.75H, d, J=18 Hz), 4.34 (2H, q, J=7Hz), 5.15 (1H, d,
J=15 Hz), 5.25 (1H, d, J=15 Hz), 5.28 (1H, d, J=5Hz),
5.31 (1H, d, J=17 Hz), 5.38 (1H, d, J= 17 Hz), 5.89 (1H,
d, J=5Hz), 7.61 (0.25H, d, J=4Hz), 7.69 (0.75H, d,
J=4Hz), 7.78 (0.75H, s), 7.86 (0.25H, s), 7.96 (0.75H, d,
J=4 Hz), 7.98 (0.25H, d, J=4 Hz), 8.14 (0.75H, s), 8.41
1
s), 7.90 (1H, d, J=4 Hz), 8.11 (1H, s); IR (KBr) cm
1770 (CˆO); FABMS m/z 626 [(M+H)+]; FABHRMS
calcd for C21H21FN9O7S3 [(M+H)+]: 626.0710, found:
626.0709.
1
(0.25H, s); IR (KBr) cm 1770 (CˆO); FABMS m/z
606 [(M+H)+]; FABHRMS calcd for C22H34N9O6S3
[(M+H)+]: 606.1012, found: 606.1014.
Compound 1v was obtained in 25% yield from com-
pound 7: 1H NMR (D2O) d 3.24 (1H, d, J=18 Hz), 3.49

M. Tsushima et al. / Bioorg. Med. Chem. 8 (2000) 2781±2789
2789
(1H, d, J=18 Hz), 4.10 (1H, dd, J=12 Hz, 4.7 Hz), 4.14
(1H, dd, J=12 Hz, 5.1 Hz), 5.24 (1H, d, J=15 Hz), 5.25
(1H, d, J=5 Hz), 5.30 (1H, d, J=15 Hz), 5.69 (1H, dd,
J=5.1 Hz, 4.7 Hz), 5.82 (2H, d, J=54 Hz), 5.88 (1H, d,
J=5 Hz), 7.57 (1H, d, J=4 Hz), 7.75 (1H, s), 8.02 (1H,
(2H, s), 5.31 (1H, d, J=5 Hz), 5.31 (1H, d, J=16 Hz),
5.37 (1H, d, J=16 Hz), 5.87 (1H, d, J=5 Hz), 7.05 (1H,
s), 7.61 (1H, d, J=4 Hz), 7.75 (1H, s), 8.07 (1H, d,
1
J=4 Hz), 8.22 (1H, s); IR (KBr) cm
FABMS m/z 609 [(M+H)+]; FABHRMS calcd for
1770 (CˆO);
1
d, J=4 Hz), 8.19 (1H, s); IR (KBr) cm 1770 (CˆO);
C22H22FN8O6S3 [(M+H)+]: 609.0808, found: 609.0824.
FABMS m/z 626 [(M+H)+]; FABHRMS calcd for
C21H21FN9O7S3 [(M+H)+]: 626.0710, found: 626.0698.
Acknowledgements
Compound 1w was obtained in 7% yield from com-
1
pound 7: H NMR (D2O) d 1.97 (6H, s), 3.15 (1H, d,
We are grateful to Mr. T. Hara and Mrs. A. Miyata for
the biological study, and to Miss S. Miki for measure-
ment of mass spectra.
J=18 Hz), 3.57 (1H, d, J=18 Hz), 5.28 (1H, d, J=
4 Hz), 5.30 (1H, d, J=15 Hz), 5.38 (1H, d, J=15 Hz),
5.83 (2H, d, J=54 Hz), 5.89 (1H, d, J=4 Hz), 7.57 (1H,
d, J=5 Hz), 7.67 (1H, s), 8.09 (1H, s), 8.11 (1H, d,
J=5 Hz); IR (KBr) cm 1 1770 (CˆO); FABMS m/z 624
[(M+H)+]; FABHRMS calcd for C22H23FN9O6S3
[(M+H)+]: 624.0917, found: 624.0909.
References and Notes
1. Tsushima, M.; Iwamatsu, K.; Tamura, A.; Shibahara, S.
Bioorg. Med. Chem. 1998, 6, 1009.
2. Tsushima, M.; Kano, Y.; Umemura, E.; Iwamatsu, K.;
Tamura, A.; Shibahara, S. Bioorg. Med. Chem. 1998, 6, 1641.
3. Miyake, A.; Yoshimura, Y.; Yamaoka, M.; Nishimura, T.;
Hashimoto, N.; Imada, A. J. Antibiot. 1992, 45, 709.
4. Ohki, H.; Kawabata, K.; Okuda, S.; Kamimura, T.;
Sakane, K. J. Antibiot. 1993, 46, 359.
5. Hata, K.; Otsuki, M.; Nishino, T. Antimicrob. Agents Che-
mother. 1992, 36, 1894.
6. Hiruma, R.; Otsuki, M.; Tashima, M.; Obana, Y.; Nishino,
T. J. Antimicrob. Chemother. 1990, 26, 769.
7. Lattrell, R.; Blumbach, J.; Duerckheimer, W.; Fehlhaber,
H.; Fleischmann, K.; Kirrstetter, R.; Mencke, B.; Scheune-
mann, K.; Schrinner, E.; Schwab, W.; Seeger, K.; Seibert, G.;
Wieduwilt, M. J. Antibiot. 1988, 41, 1374.
8. Verbist, L.; Verhaegen, J. Antimicrob. Agents Chemother.
1980, 17, 807.
9. Naito, T.; Aburaki, S.; Kamachi, H.; Narita, Y.; Okumura,
J.; Kawaguchi, H. J. Antibiot. 1986, 39, 1092.
10. A part of this work was presented at the 35th Interscience
Conference on Antimicrobial Agents and Chemotherapy:
Abstract No. 2272, San Francisco, 1995.
Compound 2m was obtained in 10% yield from com-
1
pound 7: H NMR (D2O) d 1.31 (3H, t, J=7 Hz), 3.19
(1H, d, J=18 Hz), 3.61 (1H, d, J=18 Hz), 4.28 (2H, q,
J=7 Hz), 5.05 (2H, s), 5.31 (1H, d, J=5 Hz), 5.31 (1H,
d, J=15 Hz), 5.38 (1H, d, J=15 Hz), 5.87 (1H, d,
J=5 Hz), 7.02 (1H, s), 7.62 (1H, d, J=4 Hz), 7.75 (1H,
1
s), 8.07 (1H, d, J=4 Hz), 8.22 (1H, s); IR (KBr) cm
1770 (CˆO); FABMS m/z 591 [(M+H)+]; FABHRMS
calcd for C22H23N8O6S3 [(M+H)+]: 591.0903, found:
591.0912.
Compound 2p was obtained in 32% yield from com-
pound 7: 1H NMR (D2O) d 3.16 (1H, d, J=18 Hz), 3.59
(1H, d, J=18 Hz), 3.98 (3H, s), 5.03 (2H, s), 5.28 (1H, d,
J=5 Hz), 5.29 (1H, d, J=15 Hz), 5.34 (1H, d, J=
15 Hz), 5.83 (1H, d, J=5 Hz), 6.99 (1H, s), 7.59 (1H, d,
J=4 Hz), 7.73 (1H, s), 8.04 (1H, d, J=4 Hz), 8.22 (1H,
1
s); IR (KBr) cm
[(M+H)+]; FABHRMS calcd for C21H21N8O6S3
[(M+H)+]: 577.0746, found: 577.0746.
1770 (CˆO); FABMS m/z 577
11. Jone, R. G.; Kornfeld, E. C.; McLaughlin, K. C. J. Am.
Chem. Soc. 1950, 72, 4526.
12. Tsuji, T.; Itani, H.; Ishitobi, H. Tetrahedron Lett. 1987,
28, 2745.
13. Kanai, T.; Kai, Y.; Sato, N.; Naito, T.; Kamiya, T.;
Nakamura, T.; Ogura, K. Bull. Chem. Soc. Jpn. 1993, 66,
2335.
14. Nishimura, T.; Yoshimura, Y.; Yamaoka, M.; Kawai, T.;
Miyake, A. J. Antibiot. 1991, 44, 1371.
15. Yoshimura, Y.; Miyake, A.; Nishimura, T.; Kawai, T.;
Yamaoka, M. J. Antibiot. 1991, 44, 1394.
Compound 2q was obtained in 12% yield from com-
pound 7: 1H NMR (D2O) d 3.19 (1H, d, J=18 Hz), 3.62
(1H, d, J=18 Hz), 5.05 (2H, s), 5.31 (1H, d, J=15 Hz),
5.32 (1H, d, J=5 Hz), 5.38 (1H, d, J=15 Hz), 5.80 (2H,
d, J=55 Hz), 5.88 (1H, d, J=5 Hz), 7.19 (1H, s), 7.61
(1H, d, J=4 Hz), 7.75 (1H, s), 8.07 (1H, d, J=4 Hz),
1
8.22 (1H, s); IR (KBr) cm 1770 (CˆO); FABMS m/z
595 [(M+H)+]; FABHRMS calcd for C21H20FN8O6S3
[(M+H)+]: 595.0652, found: 595.0655.
16. Nishimura, T.; Yoshimura, Y.; Miyake, A. J. Antibiot.
1992, 45, 485.
17. Yoshimura, Y.; Tomimatsu, K.; Nishimura, T.; Miyake,
A.; Hashimoto, N. J. Antibiot. 1992, 45, 721.
18. Hara, R.; Sakamoto, K.; Hisamichi, H.; Nagano, N. J.
Antibiot. 1996, 49, 1162.
Compound 2r was obtained in 14% yield from com-
pound 7: 1H NMR (D2O) d 3.18 (1H, d, J=18 Hz), 3.61
(1H, d, J=18 Hz), 4.40±4.70 (3H, m), 4.85 (1H, m), 5.05