Synthesis and activity of pyrimidinylpropenamide antibiotics: The alkyl analogues of sparsomycin

Article abstract of DOI:10.1271/bbb.67.2556

Facile syntheses of sparsomycin (3) and its four analogues (4-7) based on diastereoselective oxidation of sulfide, sulfenylation, and coupling of 6-methyluracylacryllic acid with monooxodithioacetal amine, are described. Studies on the biological activity of morphological reversion on src ^ts-NRK cells were also carried out.

Full text of DOI:10.1271/bbb.67.2556

Biosci. Biotechnol. Biochem., 67 (12), 2556–2566, 2003
Synthesis and Activity of Pyrimidinylpropenamide Antibiotics: The Alkyl
*
Analogues of Sparsomycin
Noriyuki NAKAJIMA,† Takeshi ENOMOTO, Takehiro WATANABE, Nobuyasu MATSUURA
,
and Makoto UBUKATA
Biotechnology Research Center, Toyama Prefectural University, Kosugi, Toyama 939-0398, Japan
Received June 2, 2003; Accepted July 31, 2003
Facile syntheses of sparsomycin (3) and its four
analogues (4–7) based on diastereoselective oxidation of
sulˆde, sulfenylation, and coupling of 6-methyluracyl-
acryllic acid with monooxodithioacetal amine, are
described. Studies on the biological activity of morpho-
logical reversion on srcts-NRK cells were also carried
out.
Fig. 1. Structures of the Target Compounds.
Key words: total synthesis; srcts-NRK cell; sparox-
omycin A1; pyridinylpropenamide
antibiotic; structure-activation relation-
ship
for a potential antineoplastic compound.11) Since the
ˆrst synthetic study of sparsomycin in 1976,12) syn-
thetic studies of sparsomycin,13–15) total synthesis,16–18)
biosynthesis,19,20) and structure-activity relationship
studies21–27) have been widely reported. There have
been many reports on the antitumor, antibacterial,
antifungal, and antiviral properties; however, nor-
malization of the phenotype of oncogene-trans-
formed cells by 3 and its analogues has not previously
been reported. We have already reported the
syntheses of 1–3 and six analogues. Sparsomycin (3)
and its alkyl analogues, ethyl and butyl, showed
higher morphological reversion activities than those
of 1 and 2.28) This paper reports in full our observa-
tions regarding a novel and stereoselective synthesis
of the alkyl analogues of sparsomycin, ethylspar-
somycin (4), butylsparsomycin (5), allylsparsomycin
(6), and of benzylsparsomycin (7), as well as the
biological activity of morphological reversion on
srcts-NRK cells.29) The work on sparoxomycins A1
and A2 and their analogues was not reinvestigated.
Initial studies.We have previously reported that
the pyrimidinylpropenamide antibiotics, sparoxomy-
cins A1 and A2 (1 and 2), showed remarkably ‰at
reversion activity on the transformed morphology of
temperature-sensitive mutant Rous sarcoma virus-
infected NRK cells (srcts-NRK cells) to normal
morphology in a wide range of concentration without
cytotoxicity.1,2) The structures of 1 and 2 are closely
related to the inhibitor of protein biosynthesis,
sparsomycin (3), which is a secondary metabolite of
Streptomyces sparsogenes3) or Streptomyces cus-
4)
pidosporus
,
only diŠering in the oxidation level at
the sulfur atom. Wiley and Nackellar elucidated the
structure of 3 in 1970,5) while Ottenheijm and co-
workers deduced the absolute conˆguration in 1981.6)
Sparsomycin (3) displayed broad-spectrum in vitro
activity against a variety of gram-negative and gram-
positive bacteria, and showed potent antitumor
activity. The biological activity resulted from its
ability to inhibit the peptide bond-forming step of
protein biosynthesis by interacting with the large
ribosomal subunit.7–10) These potentially important
biological activities have made 3 an attractive target
Retrosynthetic analysis. A retrosynthetic analysis
was carried out based on Helquist's protocol18) as
summarized in Scheme 1. The structure of sparsomy-
cin might enable it to be produced from 6-methyl-
uracylacryllic acid (8) and the hydroxy-protected
†
To whom correspondence should be addressed. Tel:
81-766-56-7500 ext. 568; Fax: 81-766-56-2498; E-mail: nori pu-toyama.ac.jp
＋ ＋ ＠
*
Preliminary communication, see: Nakajima, N., Enomoto, T., Matsuura, N., and Ubukata, M., Synthesis and morphological reversion
activity on srcts-NRK cells of pyrimidinylpropenamide antibiotics, sparsomycin, sparoxomycins A1, A2, and their analogues. Bioorgan-
ic & Medicinal Chemistry Letters, 8, 3331–3334 (1998).
Abbreviations: Cbz, benzyloxycarbonyl; MOM, methoxymethyl; TBHP, tert-butyl hydroperoxide; DET, diethyl tartrate; LDA, lithium
diisopropylamide; THF, tetrahydrofuran; DME, ethylene glycol dimethyl ether; DMF, -dimethylformamide; HMPA, hexamethyl-
phosphoramide; TMEDA, -tetramethylethylenediamine; DCC, dicyclohexyl carbodiimide; HOBt, 1-hydroxybenzotriazole;
HOAt, 1-hydroxy-7-azabenzotriazole
N, N
N, N, N?, N?

Synthesis and Activity of Pyrimidinylpropenamide Antibiotics
2557
Scheme 1. Retrosynthesis of Sparsomycin and Its Alkyl Analogues.
Scheme 2. Sulˆde Preparation from -Cysteine.
D
amino dithioacetal mono-
S
-oxide part (III) and to
oxidation. The results are summarized in Table 1.
When MOM-protected sulˆde 11 was oxidized by
TBHP (a decane solution) in CCl4 with 1.0 eq. of
couple these two building blocks by amide forma-
tion. The alkyl sulfenyl group of III was prepared by
sulfenylation of the methyl sulfoxide (II) with alkyl
disulˆde. In order to avoid any separation of the
diastereomeric mixture of sulfoxides, diastereoselec-
tive oxidation of sulˆde I to II was studied. The
Ti(O
and poor diastereo-selectivity were observed (entry
1). The reaction in the presence of 2.0 eq. of (2 ,3 )-
)-DET as a ligand at 20 C enabled diastereom-
ers ScSs-12 and ScRs-12 of sulfoxide36) to be isolated
in a 44 yield with 24 d.e. selectivity by an HPLC
analysis (entry 2). Desired ScSs-12 was provided in an
86 chemical yield with 65 d.e. selectivity by using
(2 )-( )-DET as the ligand (entry 3). Catalytic
oxidation was achieved by using 1,1 -bi-2-naphthol.
The addition of 0.05 eq of )-( )-1,1 -bi-
2-naphthol catalyzed selective sulˆde oxidation33,34) to
i-Pr)4 and H2O without a ligand, slow reactivity
R
R
(
＋
－
9
starting sulˆde was derived from -cysteine.
D
z
z
Results and Discussion
z
z
Diastereoselective oxidation of the sulˆde
Esteriˆcation of -cysteine and subsequent Cbz
protection aŠorded -methyl -cysteine -Cbz
derivative 9 in an 85 yield. The carboxyl group was
converted to alcohol 10 by a two-step sequence in an
S
,3
S
－
D
?
S
D
N
(
R
＋
?
z
give ScSs-12 in a 74
z
yield with 72
z
d.e. selectivity
84
z
yield, involving methyl ester formation with 2
4 W
z
at 20 in 1 h. Interestingly,
9
C
(
S
)-(
－
)-1,1
?-bi-
H2SO MeOH and subsequent lithium borohydride
2-naphthol catalyzed oxidation in a 74
z
yield to
reduction. The hydroxy group was protected by
MOM ether 11 in a 97
aŠord ScSs-12, but with no selectivity (entry 4 vs. 5).
z
yield. All reactions were
The reaction in a toluene solvent gave a comparable
relatively simple and easy to perform (5 steps, 77
overall yield) compared with the previously reported
synthesis (7 steps, 52
overall yield).18)
z
chemical yield with slightly lower selectivity of 65z
d.e. (entry 6). The CH2Cl2 solvent gave high chemical
yield of 90 but low selectivity of 33 d.e. (entry 7).
The reaction was optimized by using 0.2 equiv. of
z
z
z
Diastereoselective oxidation of the sulˆde to
sulfoxide was studied. Many useful methods for
asymmetric sulˆde oxidation have been reported in
the literature.30) After several attempts to obtain the
highest yield and selectivity, the titanium complex in
＋
(
R
)-( )-1,1
performed at 0
increased to 87
?
-bi-2-naphthol. When the reaction was
C for 2.5 h, the selectivity was
d.e. with a 59 yield (entry 8). The
C required a prolonged reaction
time to provide a slightly increased 75 chemical
yield with 85 d.e. (entry 9). A lower reaction tem-
perature provided a better chemical yield of 78
however, the d.e. selectivity dropped to 77 (entry
9
z
109
z
－
reaction at
the presence of water produced from Ti(O
tartaric acid derivatives reported by Kagan31–33) and
1,1
-bi-2-naphthol reported by Uemura34,35) were
found to achieve the required diastereoselective
i
-Pr)4 and
z
z
?
z,
z

2558
N. NAKAJIMA et al.
Table 1. Diastereoselective Oxidation of the -Methyl- -cysteinol Derivatives to Methyl Sulfoxide
S
D
Temp
Time
(h)
Yield
de
Conˆguration
of sulfur atom
Entry
Ligand
—
Eq.
Solvent
(
9
C)
(
za
)
(
zb
)
1
2
3
4
5
6
7
8
9
0
0
20
20
20
20
20
20
0
16
4
4
1
1
1
1
2.5
9.5
15
CCl4
CCl4
CCl4
CCl4
47
44
86
74
74
74
90
59
75
78
6
24
65
72
0
65
33
87
85
77
S
R
S
s
s
s
s
(2
(2
R
S
,3
,3
)-(
)-(
＋
＋
＋
＋
＋
R
)-(
＋
)-DET
)-DET
2.0
2.0
0.05
0.05
0.05
0.05
0.2
0.2
0.2
－
－
S
)-(
－
(
(
(
(
(
(
(
R
S
R
R
R
R
R
＋
)-1,1
)-1,1
)-1,1
)-1,1
?
-bi-2-naphthol
S
－
?
?
?
?
-bi-2-naphthol
-bi-2-naphthol
-bi-2-naphthol
-bi-2-naphthol
CCl4
—
)-(
)-(
)-(
)-(
)-(
toluene
CH2Cl2
CCl4
CCl4
CCl4
S
S
S
S
S
s
s
s
s
s
)-1,1
)-1,1
?
-bi-2-naphthol
－
－
10
20
10
)-1,1
?
-bi-2-naphthol
b
aIsolation yield by SiO2 column chromatography. The diastereomeric excess (de) was determined by an HPLC analysis with an RP-18 column (Mightysil
,
}
250
×
4.6 mm, 5 mm, MeOH H2O, 40 60, 1.0 ml min).
W W W
10). The desired optically pure compound, ScSs-12,
part (III) was next examined. The coupling of 838) and
13 with dicyclohexyl DCC and HOBt in DMF gave
was easily obtainable by a single recrystallization
19
from CH2Cl hexane (1 5), mp 113–114
9
C, [
a
]
amide 19 in a 56
was improved to 85
of 19 with 1
z
yield. This coupling yield of 19
2 W
W
D
by using HOAt.39) Treatment
＋
87.2
9(c
0.2, CH2Cl2). The
S
conˆguration at the
sulfur atom of ScSs-12 was conˆrmed by a spec-
z
M
HCl MeOH resulted in an inseparable
W
troscopic data comparison with the literature value.18)
epimeric 1 1 mixture of sulfoxides which was
W
contaminated. Ion exchange resin was very useful
for deprotection toward the polar sparsomycin
analogues to avoid a tedious isolation work-up
and sulfoxide epimerization. The MOM group was
removed with Dowex} 50W in MeOH to give alcohol
Construction of the dithioacetal mono-S-oxide
The amino-protecting Cbz Group of ScSs-12 was
removed under dissolved metal conditions to aŠord
methyl sulfoxide 13 in a 91
mono- -oxide structure was subjected to sulfenyla-
tion of the
z yield. The dithioacetal
S
z
20 in a 65 yield.
a
-sulˆnyl carbanion, which has already
Sparsomycin (3) and its alkyl analogues, ethylspar-
somycin (4), n-butylsparsomycin (5), allylsparsomy-
cin (6) and benzylsparsomycin (7), were synthesized
from (14a–18a) by following the optimized condi-
tions via MOM-ethers (21–25) in good yields (Scheme
been reported by Helquist.15,18) However, under the
reported conditions, sulfenylation was quite di‹cult
to reproduce, and the trithioacetal mono-
(14b) was only isolated in a 47 yield. After several
S-oxide
z
trials, in which LDA (1.0 equiv.) was slowly added
dropwise to a THF solution of a mixture of 13 and
dimethyl disulˆde (1.0 equiv.) (reverse addition), the
desired sulfenylation proceeded to obtain dithioa-
4). The optical rotation and melting point of synthet-
25
＋
65.19(c 0.28, H2O) and
ic sparsomycin (3), [
a
]
D
mp 204–206
9
C (decomposing), are in good agree-
25
D
＋
65.19(c 0.37,
ment with the literature values, [
a
]
cetal mono-
S
-oxide (14a) in a 29
z
yield (52
z
based
H2O)] and mp 207–210
9
C (decomposing).3) All these
on the consumed material) contaminated with 11
z
new compounds gave satisfactory NMR and IR data
together with HRMS. We stored sparoxomycin and
its analogues (3–7) in the dark after their recrystalli-
zation from MeOH, because the trans double bond
tended to easily isomerize to the cis-isomer in a
solution.
of 14b.37) Use of a solvent such as ether, DME or
DMF, and HMPA or TMEDA as the additive did not
improve the yield of 14a. Although improvement of
the sulfenylation conditions without the formation of
trithioacetal mono-
ry, under the reverse addition conditions, sulfenyla-
tion provided ethyl, -butyl, allyl and benzyl dithioa-
cetal mono- -oxides (15a–18a) in 35 , 36 , 7.5
and 7 yields, respectively (Scheme 3).
S-oxide (15b–18b) is still necessa-
n
Biological Activity
S
z
z
z
With sparsomycin and its analogues in hand,
the morphological reversion activity on srcts-NRK
cells was determined in a concentration-dependent
manner. The relationship between the structure and
antitumor activity of sparsomycin and its analogues
z
Synthesis of sparsomycin and its alkyl analogues
The coupling between the acid part (8) and amine

Synthesis and Activity of Pyrimidinylpropenamide Antibiotics
2559
Scheme 3. Construction of the Dithioacetal Mono-S-oxides.
Scheme 4. Syntheses of Sparsomycin (3) and Its Analogues (4–7).1)
has previously been reported for leukemia L1210
methyl sulfoxide (20) showed no activity at 530
m .
M
cells. The ID50 values of the sparsomycin analogues
rose as their lipophilicity increased, this tendency
being similar to the study on the inhibition of HeLa
S3 colony formation.40) All of the assay samples were
used after being recrystallized from MeOH as white
prisms. The results are presented in Table 3.
Although all the analogues exhibited morphological
reversion activity on srcts-NRK cells, sparsomycin (3)
The synthesized cinnamide, catechol and pyridine
derivatives instead of the pyrimidinylpropenamide
group28) also did not show any activity at 530
mM.
These ˆndings suggest that the pyrimidinyl-
propenamide group was essential and that the
monooxodithioacetal group also played an important
role in exhibiting the morphological reversion
activity.
showed the highest activity (7.8
m ). It is interesting
M
that the morphological reversion activity on srcts
-
Conclusion
NRK cells and the lipophilicity of sparsomycin were
not parallel. The minimal eŠective concentration
(MEC) of the ethyl and allyl analogues (4 and 6) was
Sparsomycin (3) and its four analogues (4–7) were
synthesized by diastereoselective oxidation of sulˆde,
sulfenylation, and coupling of the 6-methyluracyl-
acryllic acid and monooxodithioacetal amine parts.
Their morphological reversion activity on srcts-NRK
cells was also studied to ˆnd that the pyrimidinyl-
propenamide group was essential and the monoox-
twice at 15.6
m
M
, of the butyl analogue (5) was four
, of the benzyl analogue (7) and
times at 31.3
m
M
MOM-ethers (19, 21 and 22) was 8 times at 62.5
that of sparsomycin (3). MOM-ether 23 was 16-fold
less potent than 3 to show 125 . Interestingly,
m
M
m
M

2560
N. NAKAJIMA et al.
Table 2. Flat Reversion Activity on the Transformed Morpholo-
gy of srcts-NRK Cells
combined organic layers were washed with brine
(300 ml) and then dried over Na2SO4. Concentration
and subsequent puriˆcation by silica gel column
Compound
srcts-NRK, MEC (
mM)
chromatography (CH2Cl MeOH, 30 1) aŠorded
2 W
W
MOM-20 (19)
62.5
a mixture of ScSs-12 and ScRs-12 (5.2 g, 75
z
) as
20
À
530.0a
62.5
62.5
125.0
7.8
a colorless solid. The diastereomeric excess (de)
MOM-3 (21)
MOM-4 (22)
MOM-6 (23)
sparsomycin (3)
was determined by an HPLC analysis to be 85
z
z
(Mightysil} RP-18, 250 4.6 mm,
5 mm, 40
×
MeOH H O, 1.0 ml min) tR(ScSs)-12, 14.2 min
W 2
W
t
4
5
6
7
15.6
31.3
15.6
62.5
(92.5
The mixture of sulfoxides (12, 5.2 g) was recrystal-
lized from CH2Cl2 hexane (1 5) to give a 4.10 g
z z
), R(ScRs)-12, 15.3 min (7.5 ).
W
W
(79
z 9
) of ScSs-12 as colorless needles, mp 113–114 C
a
No activity at 530 mM.
(CH2Cl hexane), Rf 0.15 (CH2Cl MeOH, 20 1),
2 W
2 W
W
[a
]
＋
87.2
9
(c
0.20, CH2Cl2); 1H-NMR (CDCl3,
25
D
odithioacetal group also played an important role in
exhibiting the morphological reversion activity.
400 MHz): 7.36–7.29 (5H, m, Ph), 5.77 (1H, br d,
＝
7.5 Hz), 5.10 (2H, s), 4.63 (2H, s), 4.36–4.28
NH,
J
＝
(1H, m), 3.78 (1H, dd,
J
3.4, 10.0 Hz), 3.74 (1H,
＝ ＝
5.9, 10.0 Hz), 3.35 (3H, s), 3.04 (1H, dd, J
dd,
J
Experimental
6.6, 13.0 Hz), 2.97 (1H, dd, J 4.9, 13.0 Hz), 2.62
＝
General. All melting point (mp) data were meas-
ured with Yamato MP-21 melting point apparatus
and are uncorrected. Optical rotation values were
measured in CHCl3, H2O or MeOH with a Horiba
SEPA-300 high-sensitivity polarimeter. Synthetic
(3H, s); 13C-NMR (CDCl3, 100 MHz): 155.7, 136.3,
128.4, 128.2, 128.0, 96.6, 68.4, 66.6, 56.1, 55.3, 47.5,
39.1; IR nmax (neat) cm－1: 3326 (m), 2928 (m), 1726
(m), 1687 (s), 1541 (s), 1466 (w), 1309 (m), 1273 (m),
1142 (m), 1039 (m), 1026 (m), 727 (w), FAB-MS m z
W
sulfoxides ScSs-12 and
Mightysil} RP-18 GP column (Kanto Chemical Co.,
Japan, 250 4.6 mm, 5 m) using 40 MeOH in
S
c
R
s-12 were analyzed in a
(rel. int.): 318 (10), 317 (22), 316 (MH＋, 100), 284
(8), 176 (9), 164 (6), 91 (100); FAB HRMS m z
:
W
calcd. for C14H22 O5NS (MH＋ ), 316.1218; found,
316.1202.
×
m
z
H2O as the eluent. Retention times (tR) and integrat-
ed ratios were obtained from a Hewlett-Packard
3390A recorder. IR spectra were recorded as neat for
oils, and as KBr discs for solids, with a Shimadzu
OR-8000 spectrometer. 1H-NMR spectra were
recorded in CDCl3 or CD3OD by JEOL JNM EX-400
and JEOL JNM LA-400 instruments, while low- and
high-resolution mass spectra (MS) were measured
with a JEOL JMS AX-500 spectrometer at 70 or
15 eV. Fuji Silica Chemical Ltd. BW-300 silica gel
was used for column chromatography.
(S)-O-(methoxymethyl)-S-methyl-
oxide (13). N-(benzyloxycarbonyl)- -(methoxymeth-
yl)- -methyl- -cysteinol -oxide (12, 100 mg, 0.32
D
-cysteinol S-
O
S
D
S
mmol) was placed in the three-necked ‰ask equipped
with a dry ice condenser. A mixture of dry ice and
acetone was placed in the condenser, and the bottom
‰ask was cooled in a dry ice-acetone bath. Ammonia
gas was introduced and condensed (ca. 10 ml) in the
‰ask, and sodium (18 mg, 0.8 mmol) was added to
the ‰ask. After several minutes, the dark blue solu-
tion was gradually decolorized, and reaction was
then quenched by adding ammonium chloride
(0.28 g). The liquid ammonia was allowed to
evaporate, and the residue was extracted with CH2Cl2
(S)-N-(Benzyloxycarbonyl)-O-(methoxymethyl)-S-
methyl- -cysteinol S-oxide (12). An oven-dried,
D
300-ml three-necked ‰ask equipped with a septum
and a nitrogen inlet was charged with Ti(O -Pr)4
(0.63 g, 2.2 mmol), )-( )-1,1 -bi-2-naphthol
(1.25 g, 4.4 mmol) and carbontetrachloride (50 ml).
i
(
R
＋
?
(3 10 ml). The combined organic layers were
×
washed with brine (20 ml) and then dried over
Na2SO4. Concentration aŠorded the amine as a red
oil. This material was puriˆed by silica gel short-
To the vigorous stirred reaction mixture at 09C was
slowly added H2O (0.79 ml, 44 mmol) via syringe,
stirring being continued for 30 min. A CCl4 (20 ml)
column chromatography (CH2Cl MeOH, 10 1) and
2 W
W
solution
of
-methyl-
decane solution of TBHP (8 ml, 40–48
N
-(benzyloxycarbonyl)-
O
-(methox-
subsequent Kugelrohr distillation to aŠord 52.2 mg
ymethyl)-
S
D
-cysteinol (11, 6.6 g, 22 mmol)
(91
z
) of 13 as a colorless oil, bp 170–175
9
C
22
D
and 5–6
M
(0.45 mmHg), Rf 0.25 (CH2Cl MeOH, 10 1), [a]
2 W
W
mmol) were added, and the resulting mixture was
＋
99.8
9
(
c
1.97, CHCl3), 1H-NMR (CDCl3, 400
－
stirred at 109C for 9.5 h. The reaction was quen-
MHz): 4.64 (2H, s), 3.62–3.55 (2H, m), 3.50 (1H, dd,
＝
＝
2.7,
ched with H2O (20 ml) at that temperature. The
reaction mixture was warmed to rt, the undissolved
material was separated by Celite ˆltration, and the
J
7.1, 10.7 Hz), 3.37 (3H, s), 2.83 (1H, dd,
J
＝
9.7, 13.0 Hz), 2.64 (3H,
13.0 Hz), 2.68 (1H, dd,
J
s), 13C-NMR (CDCl3, 100 MHz): 96.6, 71.9, 59.3,
mixture was extracted with CH2Cl2 (3
×
100 ml). The
54.9, 45.9, 38.6, IR nmax (neat) cm－1: 3400 (m), 3285

Synthesis and Activity of Pyrimidinylpropenamide Antibiotics
2561
(m), 2926 (m), 1674 (m), 1296 (m), 1213 (m), 1149
(R)-O-(Methoxymethyl)-S-((ethylthio)methyl)- -
cysteinol S-oxide (15a). Sulfenylation according to
the general procedure, an using 13 (270 mg, 1.49
mmol), ethyl disulˆde (184 ml, 1.49 mmol) and LDA
solution (2.5 ml, 2.25 mmol) in THF (5 ml), aŠorded
a colorless oil which was puriˆed by silica gel column
D
(m), 1111 (m), 1037 (s), 956 (m), 916 (m), 692 (w),
FAB-MS m z (rel. int.): 187 (7), 183 (10), 182 (MH＋,
W
100), 150 (20), 118 (6), 86 (23), 45 (30); FAB HRMS
m z: calcd. for C H O NS (MH＋ ), 182.0851;
W
6
16
3
found, 182.0877.
chromatography to give 15b (108 mg, 24
ˆrst fraction and 15a (126 mg, 35 ) from the second
) was
z) from the
General procedure for sulfenylation. A 0.9
solution was prepared from 0.75 ml (5.2 mmol) of
diisopropylamine, 3.3 ml (5.2 mmol) of a 1.57
hexane solution of -BuLi and 1.75 ml of THF. 1.5
Equivalents of the LDA solution was slowly added
(within 10 min) to a stirred THF solution of ( )-
(methoxymethyl)- -methyl- -cysteinol -oxide (13)
and alkyl disulˆde at 0 C, and stirring was continued
M
LDA
z
fraction. The starting material (13, 37 mg, 14
z
M
recovered from the third fraction. Data for 15a:
20
＋
34.59(c 2.4,
n
Rf 0.32 (EtOAc MeOH, 7 1), [
a
]
W
W
D
1
CHCl3); H-NMR (CDCl3, 400 MHz): 4.61 (2H, s),
＝
＝
13.7 Hz),
S
O
-
3.78 (1H, d,
J
13.7 Hz), 3.74 (1H, d,
J
S
D
S
3.60–3.55 (2H, m), 3.52–3.45 (1H, m), 3.33 (3H, s),
9
2.91 (1H, dd, J 12.2, 13.7 Hz), 2.82 (1H, dd, J
＝ ＝
＝
7.3 Hz), 1.27 (3H, t,
for 30 min at that temperature. The reaction was
quenched by adding MeOH, and the mixture was
allowed to warm to rt. After the mixture had been
concentrated in vacuo, the residue was puriˆed by
2.7, 13.7 Hz), 2.70 (2H, q,
＝
J
J
7.3 Hz); 13C-NMR (CDCl3, 100 MHz): 96.6, 72.4,
1
56.4, 55.4, 52.8, 46.3, 27.6, 14.5; IR
n
max (neat) cm－
:
3600–3080 (br s), 2930 (m), 1559 (w), 1507 (w), 1456
silica gel column chromatography (CH2Cl MeOH,
2 W
(m), 1269 (w), 1149 (m), 110 (m), 1111 (m), 1038 (s),
＋
＋
20 1 to 10 1) to aŠord a di-sulfenylation product (b)
916 (w); FAB-MS m z (rel. int.): 264 ([M Na] ,
W
W
W
from the ˆrst fraction and mono-sulfenylation
product (a) from the second fraction as a colorless
oil. The starting material (13) was recovered as a
colorless oil from the third fraction. All compounds
were obtained as colorless oils.
28), 243 (13), 242 (MH＋, 100), 180 (16), 95 (99), FAB
HRMS m z
:
calcd. for C8H20O3NS2 (MH＋),
W
242.0885; found, 242.0898.
(R)-O-(Methoxymethyl)-S-((n-butylthio)methyl)-
-cysteinol S-oxide (16a). Sulfenylation according to
D
(R)-O-(Methoxymethyl)-S-((methylthio)methyl)-
-cysteinol S-oxide (14a). Sulfenylation according to
the general procedure using 13 (270 mg, 1.49 mmol),
butyl disulˆde (283 l, 1.49 mmol) and LDA solution
D
m
the general procedure, using 13 (282 mg, 1.56 mmol),
methyl disulˆde (181 l, 1.56 mmol) and an LDA
(2.5 ml, 2.25 mmol) in THF (5 ml) aŠorded a color-
less oil which was puriˆed by silica gel column chro-
m
solution (2.6 ml, 2.34 mmol) in THF (5 ml) aŠorded
a colorless oil which was puriˆed by silica gel column
matography to give 16b (161 mg, 30
fraction and 16a (143 mg, 36 ) from the second
fraction. The starting material (13, 30 mg, 11z) was
z) from the ˆrst
z
chromatography to give 14b (46 mg, 11
ˆrst fraction and 14a (102 mg, 29 ) from the second
fraction. The starting material (13, 124 mg, 44
was recovered from the third fraction. Data for 14a:
z) from the
z
recovered from the third fraction. Data for 16a: Rf
20
＋
9
43.3 (c 0.73,
z
)
0.35 (EtOAc MeOH, 10 1), [
a
]
W
W
D
1
CHCl3), H-NMR (400 MHz, CDCl3): 4.66 (2H, s),
3.80 (1H, d, 13.9 Hz), 3.76 (1H, d, 13.9 Hz),
4.1, 10.7 Hz), 3.64–3.59 (1H, m),
7.1, 10.7 Hz), 3.37 (3H, s), 2.97
31
Rf 0.28 (CH2Cl MeOH, 20 1), [
a
]
＋
130.6
1.29, CHCl3); H-NMR (CDCl3, 400 MHz): 4.64
(2H, s), 3.76 (1H, d, 13.7 Hz), 3.68 (1H, d,
13.7 Hz), 3.58 (1H, dd,
9
J
＝
J
＝
2 W
W
D
1
＝
J
(
c
3.61 (1H, dd,
3.51 (1H, dd, J
＝
J
＝
J
＝
＝
＝
＝
J
J
5.3, 9.5 Hz), 3.55 (1H,
(1H, dd,
J
9.9, 12.9 Hz), 2.81 (1H, dd,
2.7,
＝
7.3 Hz), 1.60 (2H, quintet,
＝
dd,
J
3.5, 9.5 Hz), 3.52–3.45 (1H, m), 3.33 (3H, s),
12.9 Hz), 2.74 (2H, t,
J
2.87 (1H, dd,
J
＝
10.2, 12.9 Hz), 2.81 (1H, dd,
J
＝
J
J
＝
＝
7.3 Hz), 1.43 (2H, sextet,
J
＝
7.3 Hz), 0.92 (3H, t,
7.3 Hz), C-NMR (100 MHz, CDCl3): 96.6, 72.3,
3.5, 12.9 Hz), 2.33 (3H, s); 13C-NMR (CDCl3,
100 MHz): 96.6, 72.4, 56.5, 55.4, 55.1, 46.3, 17.2; IR
nmax (neat) cm－1: 3400 (m), 3285 (m), 2926 (m), 2826
(w), 1674 (m), 1410 (w), 1296 (m), 1213 (w), 1150
(m), 1111 (s), 1038 (s), 957 (m), 916 (m); FAB-MS
13
56.3, 55.4, 53.2, 46.4, 33.5, 31.4, 21.7, 13.5, IR nmax
(neat) cm－1: 3360 (w), 2957 (m), 2930 (m), 2874 (s),
1670 (w), 1460 (w), 1380 (w), 1150 (m), 1111 (m),
1038 (s), 918 (m); FAB-MS m z (rel. int.): 272 (4),
W
m z (rel. int.): 230 (13), 229 (17), 228 (MH＋, 83), 183
271 (5), 270 (MH＋, 35), 192 (6), 167 (17), 149 (100),
W
(67), 107 (100); FAB HRMS m z: calcd. for
103 (27), 61 (48), FAB HRMS m z: calcd. for
W
W
C7H18O3NS2 (MH＋ ), 228.0728; found, 228.0737.
Data for 14b: 1H-NMR (CDCl3, 400 MHz):
4.63–4.60 (3H, s, OCH2O and CH(SMe)2), 3.65 (1H,
C10H24O3NS2 (MH＋), 270.1198; found, 270.1298.
(R)-O-(Methoxymethyl)-S-((allylthio)methyl)- -
D
＝
＝
dd,
dd,
J
J
4.7, 11.5 Hz), 3.65–3.57 (1H, m), 3.52 (1H,
5.4, 11.5 Hz), 3.38 (3H, s), 3.02–3.00 (2H,
cysteinol S-oxide (17a). Sulfenylation according to
the general procedure, using 13 (181 mg, 1.00 mmol),
m), 2.38 (3H, s), 2.37 (3H, s), 13C-NMR (CDCl3,
100 MHz): 96.6, 72.5, 71.9, 55.4, 55.0, 46.6, 15.7,
z
allyl disulˆde (80 , 181
m
l, 1.0 mmol) and a 0.5
M
LDA solution (2.0 ml, 1.00 mmol) in THF (10 ml),
aŠorded a colorless oil which was puriˆed by silica
15.4; FAB-MS m z (rel. int.): 274 (MH＋ ).
W

2562
N. NAKAJIMA et al.
gel column chromatography to give 17b (56.1 mg,
17 ) from the ˆrst fraction and 17a (18.9 mg, 7.5
from the second fraction. The starting material (13,
(E)-(Ss)-N-[2-(Methylsulˆnyl)-1-[(methoxymethyl-
oxy)methyl]ethyl]-3-(1,2,3,4-tetrahydro-6-methyl-
2,4-dioxo-5-pyrimidinyl)-2-propenamide (19). Cou-
pling according to the general procedure, using
8 (157.6 mg, 0.93 mmol), 13 (140.0 mg, 0.77 mmol),
DCC (191 mg, 0.93 mmol), and HOAt (126.0 mg,
0.93 mmol) in DMF (5 ml), aŠorded a solid which
was puriˆed by silica gel column chromatography to
z
z)
111 mg, 61
z
) was recovered from the third fraction.
31
D
1
Data for 17a: [
a
]
＋
103.3
9
(
c
0.68, CHCl3); H-
＝
17.5,
1.0, 10.0 Hz), 5.21
NMR (CDCl3, 400 MHz): 5.76 (1H, ddt,
J
＝
10.1, 7.3 Hz), 5.22 (1H, dd,
J
＝
J
(1H, dd,
1.0, 17.5 Hz), 4.64 (2H, s), 3.74 (1H, d,
＝
＝
13.7 Hz), 3.62–3.48
J
13.7 Hz), 3.71 (1H, d,
J
give 235.3 mg (85z) of 19 as a white solid, mp
27
(3H, m), 3.36 (3H, s), 3.31 (2H, d,
J
＝
7.3 Hz), 2.91
124–127
9
C, Rf 0.25 (EtOAc MeOH, 3 1), [
a
]
D
W
W
(1H, dd,
J
9.8, 12.7 Hz), 2.81 (1H, dd,
J
3.0,
121.59 (c
0.56, MeOH); 1H-NMR (D2O, 400
＝
＝
＋
12.7 Hz); 13C-NMR (CDCl3, 100 MHz): 132.4, 119.4,
MHz): 7.19 (1H, d,
J
＝ ＝
15.5 Hz), 6.87 (1H, d, J
96.6, 72.4, 56.5, 55.4, 50.7, 46.4, 35.6; IR nmax (neat)
15.5 Hz), 4.56 (2H, s), 4.49–4.41 (1H, m), 3.63 (1H,
cm－1: 3368 (m), 2928 (m), 1636 (w), 1404 (w), 1150
dd,
J
4.8, 10.7 Hz), 3.58 (1H, dd,
J
5.8, 10.7 Hz),
＝
＝
(m), 1112 (m), 1040 (s), 920 (m); FAB-MS m z (rel.
3.22 (3H, s), 2.99 (1H, t,
J
＝
11.5 Hz), 2.98 (1H, dd,
W
int.): 254 (MH＋, 1.2), 253 (4.4), 179 (74), 148 (24),
J
8.8, 11.5 Hz), 2.59 (3H, s), 2.19 (3H, s); 13C-
＝
130 (27), 87 (100), 72 (39); FAB HRMS m z: calcd.
NMR (D2O, 100 MHz): 169.9, 165.3, 157.5, 152.3,
133.2, 121.1, 106.4, 97.0, 69.7, 56.2, 55.9, 45.6, 38.1,
17.5; IR nmax (KBr) cm－1: 3300 (m), 3063 (w), 3002
(w), 2950 (m), 2911 (m), 2820 (m), 1659 (s), 1633 (s),
1547 (s), 1339 (m), 1254 (m), 1172(w), 1109 (s), 10518
W
for C9H19 O3NS2 (MH＋), 253.0806; found, 253.0829.
(R)-O-(Methoxymethyl)-S-((benzylthio)methyl)- -
D
cysteinol S-oxide (18a). Sulfenylation according to
the general procedure, using 13 (181 mg, 1.00 mmol),
(s), 1024 (s), 972 (m), 767 (m); FAB-MS m z (rel.
W
benzyl disulˆde (98
z
purity, 251 mg, 1.00 mmol)
int.): 362 (22), 361 (48), 360 (MH＋, 100), 182 (83),
and a 0.5 LDA solution (2.0 ml, 1.00 mmol) in
M
179 (58); FAB HRMS m z: calcd. for C H O N S
W
14
22
6
3
THF (10 ml), aŠorded a colorless oil which was
puriˆed by silica gel column chromatography to give
(MH＋), 360.1229; found, 360.1217.
18b (84.9 mg, 20
(20.2 mg, 7 ) from the second fraction. The starting
material (13, 92.0 mg, 51
z) from the ˆrst fraction and 18a
O-(Methoxymethyl)sparsomycin (21). Coupling
z
according to the general procedure, using 8 (23.5 mg,
0.12 mmol), 14a (23.7 mg, 0.104 mmol), DCC
(24.8 mg, 0.12 mmol), and HOAt (16.3 mg, 0.12
mmol) in DMF (1 ml), aŠorded a solid which was
puriˆed by silica gel column chromatography to give
z) was recovered from the
third fraction. Data for 18a: Rf 0.32 (EtOAc
W
30
＋
MeOH, 7 1), [
a
]
9
110.1 (c
1.0, CHCl3); 1H-NMR
W
D
(CDCl3, 400 MHz): 7.34–7.33 (5H, m), 4.63 (2H, s),
3.92 (1H, dd, 4.2, 8.8 Hz), 3.66 (1H, d,
J
＝
J
＝
35.6 mg (88
z
) of 21 as a white solid. An assay
＝
13.7 Hz), 3.58 (1H, dd,
13.7 Hz), 3.59 (1H, d,
J
sample was obtained by crystallization from MeOH
J
J
＝
＝
4.2, 8.8 Hz), 3.59–3.52 (1H, m), 3.48 (1H, dd,
as a white prism, mp 115–117
9
C (decomposing), Rf
23
D
＝
＋
44.0
5.1, 8.8 Hz), 3.36 (3H, s), 2.87 (1H, dd,
J
9.2,
0.35 (EtOAc MeOH, 8 1), [
a
]
9
(c
2.2,
W
W
12.7 Hz), 2.81 (1H, dd,
J
3.5, 12.7 Hz); 13C-NMR
H2O); H-NMR (D2O, 400 MHz): 7.20 (1H, d,
J
1
＝
＝
(CDCl3, 100 MHz): 136.4, 129.2, 127.6, 96.6, 72.3,
56.5, 55.4, 51.2, 46.4, 36.9; IR
max (neat) cm－1: 3370
(s), 2928 (m), 1601 (w), 1459 (w), 1150 (m), 1111 (m),
15.3 Hz), 6.87 (1H, d,
J
＝
15.3 Hz), 4.56 (2H, s),
＝
J
＝
n
4.52–4.46 (1H, m), 3.94 (1H, d,
(1H, d, 13.9 Hz), 3.65 (1H, dd,
3.60 (1H, dd,
J
13.9 Hz), 3.77
4.7, 10.7 Hz),
5.6, 10.7 Hz), 3.22 (3H, s), 3.08
J
＝
＝
J
1038 (s), 916 (w), 704 (m); FAB-MS m z (rel. int.):
W
＋
＋
＋
＝
＝
10.2, 13.5 Hz), 3.02 (1H, dd, J 4.1,
326 ([M Na] , 18), 305 (16), 304 (MH , 84), 180
(1H, dd,
J
(20), 137 (47), 91 (100); FAB HRMS m z: calcd. for
13.5 Hz), 2.18 (3H, s), 2.11 (3H, s); 13C-NMR (D2O,
100 MHz): 169.8, 165.3, 157.3, 152.1, 133.2, 121.2,
106.5, 97.0, 69.7, 55.9, 55.3, 53.6, 45.6, 17.4, 16.8;
IR nmax (KBr) cm－1: 3440 (s), 3280 (m), 2820 (w),
1720 (s), 1655 (s), 1620 (m), 1610 (m), 1530 (m), 1460
(w), 1440 (m), 1350 (w), 1300 (w), 1210 (w), 1150 (w),
W
C13H22O3NS2 (MH＋), 304.1041; found, 304.1060.
General procedure for coupling between of (E)-3-
(6-methyl-5-uracilyl)-2-propeonic acid (8) and the
amine part (III). A solution of amine part III in DMF
was added to a DMF solution of ( )-3-(6-methyl-5-
E
1125 (m), 1045 (m), 1000 (w), 918 (w); FAB-MS m z
W
uracilyl)-2-propeonic acid (8), DCC, and HOAt. The
reaction mixture was stirred for 12 h at room temper-
ature. The reaction was concentrated, and the residue
was directly puriˆed by silica gel column chro-
(rel. int.): 408 (19), 407 (23), 406 (MH＋, 66), 360
(16), 344 (16), 228 (25), 179 (100); FAB HRMS m z
:
W
calcd. for (MH＋) C15H24O6N3S2, 406.1107; found,
406.1110.
matography (CH2Cl MeOH, 9 1) and subsequent
2 W
W
concentration of the appropriate fraction in vacuo to
O-(Methoxymethyl)ethylsparsomycin (22). Cou-
pling according to the general procedure, using
8 (58.5 mg, 0.3 mmol), 15a (66.4 mg, 0.28 mmol),
DCC (62.0 mg, 0.3 mmol), and HOAt (41 mg, 0.3
give the indicated yields of products as white solids.

Synthesis and Activity of Pyrimidinylpropenamide Antibiotics
2563
mmol) in DMF (1 ml), aŠorded a solid which was
puriˆed by silica gel column chromatography to give
was puriˆed by silica gel column chromatography to
give 22.9 mg (86 ) of 24 as a white solid, mp
z
z
107 mg (93 ) of 22 as a white solid. An assay sample
192–193
9
C (decomposing), Rf 0.21 (CH2Cl MeOH,
2 W
0.21, MeOH); H-NMR (400
15.2 Hz), 7.22 (1H,
30
D
1
＋
98.99(c
was obtained by crystallization from MeOH as a
10 1), [
a
]
W
white prism: mp 169–172
9
]
C (decomposing), Rf 0.4
D
MHz, CD3OD): 7.44 (1H, d,
J
＝
23
＋
＝
＝
J 10.0, 17.1, 7.3
(EtOAc MeOH, 6 1), [
a
46.8
9(
c
2.4, MeOH);
d,
J
15.2 Hz), 5.81 (1H, ddt,
W
W
1H-NMR (400 MHz, D2O): 7.29 (1H, d,
J
15.6 Hz),
Hz), 5.20 (1H, dd,
J
1.2, 17.1 Hz), 5.19 (1H, dd,
＝
＝
＝
＝
1.0, 10.0 Hz), 4.66 (2H, s), 4.66–4.58 (1H, m),
6.92 (1H, d,
4.00 (1H, d,
3.67 (1H, dd,
10.5 Hz), 3.25 (3H, s), 3.14 (1H, dd,
Hz), 3.02 (1H, dd,
J
15.6 Hz), 4.58 (2H, s), 4.56 (1H, m),
J
＝
＝
＝
＝
J
＝
J
14.1 Hz), 3.85 (1H, d,
J
14.1 Hz),
5.3,
8.7, 13.7
3.97 (1H, d,
3.68 (2H, d,
J
13.9 Hz), 3.80 (1H, d, 13.9 Hz),
J
＝
4.7, 10.5 Hz), 3.63 (1H, dd,
J
＝
J
＝
5.1 Hz), 3.36 (2H, d, J 7.3 Hz),
＝
＝
10.4, 13.4 Hz), 3.09
J
3.35 (3H, s), 3.21 (1H, dd,
J
J
3.7, 13.7 Hz), 2.61 (2H,
(1H, dd,
J
3.6, 13.4 Hz), 2.35 (3H, s); 13C-NMR
＝
＝
7.5 Hz); 13C-NMR
(100 MHz, CD3OD): 169.5, 164.8, 156.2, 151.6,
134.4, 133.0, 122.1, 119.4, 106.7, 97.7, 70.0, 55.7,
＝
＝
q,
J
7.5 Hz), 1.12 (3H, t,
J
(100 MHz, D2O): 170.0, 165.7, 157.7, 152.5, 133.4,
121.2, 106.6, 97.0, 69.8, 55.9, 53.8, 53.1, 45.7, 28.0,
17.5, 14.9; IR nmax (KBr) cm－1: 3447 (m), 2955 (m),
2936 (m), 2826 (m), 1717 (s), 1684 (s), 1608 (s), 1456
(m), 1340 (m), 1302 (m), 1213 (w), 1151 (s), 1034 (m),
54.9, 52.2, 46.2, 36.6, 16.9; IR n
max (KBr) cm－1: 3260
(m), 2920 (m), 2820 (m), 1719 (s), 1655 (s), 1650 (s),
1541 (s), 1522 (s), 1509 (s), 1459 (m), 1341 (m), 1113
(m), 1040 (m), 999 (m); FAB-MS m z (rel. int.): 454
W
＋
＋
＋
([M Na] , 8), 433 (5), 432 (MH , 20), 398 (27), 373
862 (w); FAB-MS m z (rel. int.): 422 (3), 421 (5), 420
W
(MH＋, 15), 404 (6), 388 (11), 356 (8), 328 (8), 284 (6),
(26), 254 (20), 179 (78), 87 (100), FAB HRMS m z:
W
calcd. for C17H26O6N3S2 (MH＋), 432.1263; found,
432.1271.
242 (10), 179 (66), 76 (100); FAB HRMS m z: calcd.
W
for C16H26O6N3S2 (MH＋), 420.1263; found,
420.1262.
O-(Methoxymethyl)benzylsparsomycin (25). Cou-
pling according to the general procedure, using
8 (15.5 mg, 0.08 mmol), 18a (20.0 mg, 0.66 mmol),
and HOAt (10.8 mg, 0.08 mmol) in DMF (1 ml),
aŠorded a solid which was puriˆed by silica gel
O-(Methoxymethyl)n-butylsparsomycin (23). Cou-
pling according to the general procedure, using
8 (53.2 mg, 0.27 mmol), 16a (61.0 mg, 0.23 mmol),
DCC (56.0 mg, 0.27 mmol), and HOAt (37.0 mg,
0.27 mmol) in DMF (1 ml), aŠorded a solid which
was puriˆed by silica gel column chromatography to
column chromatography to give 26.0 mg (82
z
) of
C (decomposing),
＋
109.5 (c 0.31, MeOH); H-NMR (400 MHz,
25 as a white solid, mp 217.5–219
9
23
D
1
give 95.6 mg (95
z
) of 23 as a white solid. An assay
[a
]
＝
sample was obtained by crystallization from MeOH
CD3OD): 7.43 (1H, d,
J
15.4 Hz), 7.35–7.29 (2H,
15.4 Hz),
as a white prism, mp 203–204.5
9
C (decomposing),
m), 7.26–7.21 (1H, m), 7.22 (1H, d, J
＝
23
D
＋
Rf 0.28 (EtOAc MeOH, 8 1), [
a
]
31.6 (
c
1.1,
4.63 (2H, s), 4.64–4.55 (1H, m), 3.94 (2H, s), 3.88
W
W
1
MeOH); H-NMR (400 MHz, CD3OD): 7.44 (1H, d,
(1H, d,
(2H, d,
J
J
＝
＝
13.9 Hz), 3.70 (1H, d,
＝
5.2, Hz), 3.34 (3H, s), 3.18 (1H, dd, J
J 13.9 Hz), 3.67
＝
＝
＝
J
15.3 Hz), 7.21 (1H, d,
4.66–4.61 (1H, m), 4.01 (1H, d,
(1H, d, 13.9 Hz), 3.69 (2H, d,
(3H, s), 3.23 (1H, dd,
dd, 3.4, 13.3 Hz), 2.76 (2H, t,
(2H, quintet,
Hz), 0.91 (3H, t,
J
15.3 Hz), 4.64 (2H, s),
＝
＝
3.9, 13.4 Hz), 2.34
J
13.9 Hz), 3.87
5.1 Hz), 3.35
10.2, 13.4 Hz), 3.05 (1H, dd,
J
J
＝
J
＝
(3H, s); 13C-NMR (100 MHz, CD3OD): 169.3, 164.7,
156.0, 151.8, 138.1, 132.9, 130.3, 129.7, 128.5,
122.1, 106.7, 97.6, 69.9, 55.8, 54.9, 52.8, 46.1, 37.9,
16.9, IR (KBr) 3285 (m), 2960 (m), 2822 (m), 1719
(s), 1701 (s), 1694 (s), 1541 (s), 1439 (m), 1350 (m),
1300 (m), 1221 (m), 1148 (m), 1109 (m), 1034 (s), 770
＝
J
10.3, 13.2 Hz), 3.07 (1H,
J
＝
J 7.1 Hz), 1.60
＝
＝
＝
7.3
J
7.3 Hz), 1.40 (2H, sextet,
J
＝
J
7.3 Hz); 13C-NMR (100 MHz,
CD3OD): 169.5, 164.8, 156.3, 151.9, 133.0, 122.1,
106.7, 97.7, 70.1, 55.7, 55.0, 54.4, 46.3, 34.3, 32.7,
22.7, 16.9, 13.9; IR nmax (KBr) cm－1: 2957 (m), 2934
(m), 2826 (w), 1723 (s), 1717 (s), 1674 (s), 1609 (m),
1539 (m), 1456 (m), 1304 (m), 1302(m), 1211 (m),
＋
(w), 698 (w); FAB-MS m z (rel. int.): 504 ([M
W
Na]＋, 21), 483 (7), 482 (MH＋, 20), 179 (34), 91 (100);
FAB HRMS m z: calcd. for C H O N S (MH＋),
W
21
28
6
3
2
482.1420; found, 482.1419.
1151 (m), 1113 (m), 1039 (m), 916 (w); FAB-MS m z
W
(rel. int.): 450 (13), 449 (25), 448 (MH＋, 100), 373
(14), 324 (16), 264 (5), 242 (44), 180 (6), 148 (8); FAB
General procedure for MOM deprotection.
Dowex} 50W (H＋) was added to a solution of the
MOM ether in MeOH. The suspension was stirred
HRMS m z
:
calcd. for C18H30O6N3S2 (MH＋),
W
448.1577; found, 448.1577.
for 2 h at 50
9C, and the Dowex resin was ˆltered oŠ.
Concentration and subsequent puriˆcation by silica
O-(Methoxymethyl)allylsparsomycin
(
24). Cou-
gel column chromatography (CH2Cl MeOH, 10 1)
2 W W
gave the deprotected products as white solids.
pling according to the general procedure, using
8 (14.5 mg, 0.074 mmol), 17a (15.6 mg, 0.062 mmol),
DCC (515.2 mg, 0.074 mmol), and HOAt (10.4 mg,
0.074 mmol) in DMF (1 ml), aŠorded a solid which

2564
N. NAKAJIMA et al.
＝
＝
＝
13.9 Hz), 3.68 (1H, dd,
(E)-(Ss)-N-[1-(Hydroxymethyl)ethyl-2-(methylsul-
J
J
13.9 Hz), 3.88 (1H, d,
J
＝
5.4, 10.9 Hz),
ˆnyl)]-3-(1,2,3,4-tetrahydro-6-methyl-2,4-dioxo-5-
pyrimidinyl)-2-propenamide (20). Deprotection ac-
cording to the general procedure, using 19 (53.6 mg,
0.15 mmol) and Dowex} 50W (H＋) (100 mg) in
MeOH (10 ml), aŠorded a solid which was puriˆed
5.4, 10.9 Hz), 3.66 (1H, dd,
J
＝ ＝
10.2, 13.1 Hz), 3.06 (1H, dd, J
3.19 (1H, dd,
3.7, 13.1 Hz), 2.76 (2H, q,
1.27 (3H, t,
7.6 Hz); 13C-NMR (100 MHz,
J
＝
J
7.6 Hz), 2.35 (3H, s),
J
＝
CD3OD): 169.6, 164.8, 156.2, 151.9, 132.8, 122.3,
106.8, 64.6, 54.7, 54.1, 48.2, 28.5, 16.9, 15.1; IR nmax
(KBr) cm－1: 3250 (m), 2970 (m), 2934 (m), 2818 (m),
1713 (s), 1668 (s), 1540 (m), 1447 (m), 1311 (w), 1219
by silica gel column chromatography (CH2Cl2
W
MeOH, 9 1) to give 29.6 mg (63
z
) of 20 as a white
W
solid. An assay sample was obtained by crystalliza-
1
tion from MeOH as a white prism, H-NMR (400
(w), 1084 (w), 1011 (m), 860 (m); FAB-MS m z (rel.
W
＋ ＋
＝
＋
MHz, CD3OD): 7.27 (1H, d,
J
15.6 Hz), 6.92 (1H,
int.): 398 ([M Na] , 45), 377 (9), 376 (MH , 33),
＝
＝
d,
J
15.6 Hz), 4.40–4.34 (1H, m), 3.66 (1H, dd,
J
176 (100); FAB HRMS m z: calcd. for C H O N S
W
14
22
5
3
2
＝
4.6, 11.7 Hz), 3.58 (1H, dd,
J
5.8, 11.7 Hz),
(MH＋), 376.1001; found, 376.1003.
3.05–2.96 (2H, m), 2.65 (3H, s), 2.28 (3H, s); 13C-
NMR (100 MHz, CD3OD): 169.7, 165.0, 156.9,
152.0, 132.9, 122.0, 106.7, 64.1, 56.9, 47.9, 38.6,
n-Butylsparsomycin (5). Deprotection according to
the general procedure, using 23 (48.0 mg, 0.11 mmol)
and Dowex} 50W (H＋) (500 mg) in MeOH (10 ml),
aŠorded a solid which was puriˆed by silica gel
17.3; IR n
max (KBr) cm－1: 3300 (s), 2950 (s), 2826 (s),
1710 (s), 1671 (s), 1603 (s), 1541 (s), 1429 (s), 1356
(m), 1306 (m), 1047 (s); FAB-MS m z (rel. int.): 318
column chromatography to give 38.3 mg (88z) of
W
(17), 317 (33), 316 (MH＋, 100), 224 (58), 179 (33),
5 as a white solid. An assay sample was obtained by
138 (33); FAB HRMS m z: calcd. for C H O N S
crystallization from MeOH as a white prism, mp
W
12
18
5
3
(MH＋), 316.0967; found, 316.0934.
225–226
9
C (decomposing), Rf 0.2 (EtOAc MeOH,
W
0.82, MeOH); 1H-NMR
23
D
＋
6 1), [
a
]
89.2
9
(c
W
＝
15.4 Hz), 7.23
Sparsomycin ( ). Deprotection according to the
3
(400 MHz, CD3OD): 7.42 (1H, d,
J
general procedure using 21 (62 mg, 0.153 mmol) and
Dowex} 50W (H＋) (100 mg) in MeOH (10 ml)
aŠorded a solid, which was puriˆed by silica gel
(1H, d,
＝
＝
J
＝
15.4 Hz), 4.51–4.44 (1H, m), 4.02 (1H, d,
＝
J
J
14.0 Hz), 3.88 (1H, d,
J
14.0 Hz), 3.69 (2H, d,
＝
5.4 Hz), 3.20 (1H, dd,
J
10.5, 13.4 Hz), 3.06
7.3 Hz),
7.3 Hz), 1.40 (2H,
7.4 Hz); 13C-NMR
column chromatography to give 41 mg (74
z
) of 3 as
(1H, dd,
2.34 (3H, s), 1.58 (2H, quint,
extet, 7.4 Hz), 0.90 (3H, t,
J
＝
3.7, 13.4 Hz), 2.74 (2H, t, J
＝
＝
a white solid. An assay sample was obtained by crys-
J
tallization from MeOH as a white prism, Rf 0.1
J
＝
J
＝
25
＋
(EtOAc MeOH, 6 1), [
a
]
65.1
9
(
c
0.28, H2O),
(100 MHz, CD3OD): 169.6, 164.8, 156.2, 151.9,
132.8, 122.3, 106.8, 64.6, 54.8, 54.4, 48.2, 34.3, 32.7,
22.7, 17.0, 14.0; IR nmax (KBr) cm－1: 3260 (m), 2960
(m), 2932 (m), 2870 (m), 1706 (s), 1655 (s), 1541 (m),
1508 (m), 1458 (m), 1320 (w), 1225 (w), 1036 (w),
W
W
D
1
mp 204–206
9
C (decomposing); H-NMR (400 MHz,
15.3 Hz), 6.88 (1H, d, 15.5
13.9 Hz),
13.9 Hz), 3.62 (1H, dd, 4.9,
5.8, 11.7 Hz), 3.01 (2H,
D2O): 7.22 (1H, d,
J
＝
J
＝
＝
J
Hz), 4.43–4.36 (1H, m), 3.94 (1H, d,
3.77 (1H, d,
11.7 Hz), 3.55 (1H, dd,
J
＝
J
＝
＝
J
1019 (m); FAB-MS m z (rel. int.): 405 (9), 404
W
m), 2.20 (3H, s), 2.10 (3H, s); 13C-NMR (100 MHz,
D2O): 170.0, 165.4, 157.4, 152.2, 133.1, 121.3,
106.6, 63.7, 55.3, 53.5, 47.4, 17.4, 16.8; IR nmax
(KBr) cm－1: 3400 (w), 2820 (m), 1720 (s), 1660 (s),
1542 (s), 1433 (s), 1360 (m), 1308 (m), 1080 (w), 1010
(MH＋, 32), 388 (28), 250 (18), 239 (58), 179 (100);
FAB HRMS m z: calcd. for C H O N S (MH＋),
W
16
26
5
3
2
404.1314; found, 404.1312.
Allylsparsomycin (6). Deprotection according to
(s), 978 (m), 860 (w), 780 (w), 536 (s); FAB-MS m z
the general procedure, using 24 (12.0 mg, 28.0 mmol)
W
(rel. int.): 384 ([M
39), 346 (5), 207 (44), 179 (39), 115 (100); FAB
HRMS m z
calcd. for C13H20O5N3S2 (MH＋),
362.0844; found, 362.0854.
＋
Na]＋, 10), 363 (10), 362 (MH＋,
and Dowex} 50W (H＋) (100 mg) in MeOH (5 ml),
aŠorded a solid which was puriˆed by silica gel
:
W
z
column chromatography to give 9.4 mg (87 ) of 6 as
a white solid. An assay sample was obtained by crys-
tallization from MeOH as a white prism, mp 225–
30
Ethylsparsomycin (
4
). Deprotection according to
226
9
C (decomposing), [
a
]
＋
66.9
9
(
c
0.28, MeOH);
D
＝
the general procedure, using 22 (15.4 mg, 37.0
m
mol)
1H-NMR (400 MHz, CD3OD): 7.43 (1H, d,
J
15.3
and Dowex} 50W (H＋) (500 mg) in MeOH (10 ml),
aŠorded a solid which was puriˆed by silica gel
Hz), 7.22 (1H, d,
10.0, 17.1, 7.4 Hz), 5.20 (1H, qd,
J
15.3 Hz), 5.81 (1H, ddt,
J
＝
＝
＝
J
1.4, 17.4 Hz),
＝ ＝
1.0, 10.0 Hz), 4.46 (1H, dddd, J
column chromatography to give 11.7 mg (85
z) of
5.18 (1H, qd,
3.9, 5.0, 5.6, 10.3 Hz), 3.96 (1H, d,
J
4 as a white solid. An assay sample was obtained by
J 13.9 Hz),
＝
＝
＝
5.0, 11.0
crystallization from MeOH as a white prism, mp
3.79 (1H, d,
Hz), 3.66 (1H, dd,
J
13.9 Hz), 3.69 (1H, dd,
J
＝
221.5–222.5
9
C
(decomposing), Rf 0.2 (EtOAc
D
J
5.6, 11.0 Hz), 3.36 (1H, dt,
J
W
MeOH, 6 1), [
a
]
64.6
9
(c
0.81, MeOH); 1H-NMR
7.3, 1.0 Hz), 3.18 (1H, dd,
J
10.3, 13.4 Hz), 3.08
23
＋
＝
(1H, dd,
＝
W
3.9, 13.4 Hz), 2.35 (3H, s); 13C-NMR
＝
＝
(400 MHz, CD3OD): 7.42 (1H, d,
J
15.3 Hz), 7.24
J
(1H, d, J 15.3 Hz), 4.51–4.44 (1H, m), 4.02 (1H, d,
＝
(100 MHz, CD3OD): 169.6, 164.8, 156.2, 151.9,

Synthesis and Activity of Pyrimidinylpropenamide Antibiotics
2565
134.4, 132.9, 122.3, 119.4, 106.8, 64.6, 54.8, 52.3,
48.2, 36.6, 16.9; IR
max (KBr) cm－1: 3600–3800 (m),
Physical and Chemical Research (RIKEN) is grate-
fully acknowledged.
n
1717 (s), 1675 (s), 1617 (s), 1540 (m), 1458 (s), 1430
(s), 1354 (s), 1341 (s), 1300 (m), 1217 (m), 1088 (m),
References
986 (s), 864 (m); FAB-MS m z (rel. int.): 389 (24),
W
388 (MH＋, 69), 179 (100); FAB HRMS m z: calcd.
1) Ubukata, M., Morita, T., Kakeya, H., Kobinata, K.,
Kudo, T., and Osada, H., Sparoxomycins A1 and
A2, new inducers of the ‰at reversion of NRK cells
transformed by temperature sensitive rous sarcoma
virus, I. Taxonomy of the producing organism,
W
for C15H21O5N3S2 (MH＋), 388.1001; found,
388.0990.
Benzylsparsomycin (7). Deprotection according
fermentation and biological activity. J. Antibiotics
49, 1096–1100 (1996).
,
to the general procedure, using 25 (14.1 mg, 0.029
mmol) and Dowex} 50W (H＋) (100 mg) in MeOH
(5 ml), aŠorded a solid which was puriˆed by silica
2) Ubukata, M., Morita, T., Uramoto, M., and Osada,
H., Sparoxomycins A1 and A2, new inducers of the
‰at reversion of NRK cells transformed by tempera-
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3) Argoudelis, A. D., and Herr, R. R., Sparsomycin, a
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6) Ottenheijm, H. C. J., Liskamp, R. M. J., Helquist,
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(1981).
gel column chromatography to give 8.4 mg (66
z) of
7 as a white solid. An assay sample was obtained by
crystallization from MeOH as a white prism, mp
23
＋
51.19(c 0.40,
226.5–228
9
C (decomposing), [
a
]
D
1
MeOH); H-NMR (400 MHz, CD3OD): 7.44 (1H, d,
＝
J
15.3 Hz), 7.36–7.30 (4H, m), 7.26–7.20 (1H, m),
7.22 (1H, d, 15.3 Hz), 4.48–4.42 (1H, m), 3.95
(2H, s), 3.90 (1H, d,
13.9 Hz), 3.67 (1H, dd,
J
＝
＝
J
＝
13.9 Hz), 3.73 (1H, d, J
J
＝
4.9, 12.2 Hz), 3.65 (1H,
＝
＝
dd,
J
5.4, 12.2 Hz), 3.15 (1H, dd,
J
10.2, 12.2
＝
Hz), 3.05 (1H, dd,
J
3.7, 13.2 Hz), 2.34 (3H, s);
13C-NMR (100 MHz, CD3OD): 169.6, 164.8, 156.2,
151.9, 138.4, 132.9, 130.5, 129.8, 128.6, 122.3,
106.8, 64.6, 54.9, 52.9, 48.1, 37.9, 16.9; IR nmax
(KBr) cm－1: 3260 (m), 3060 (m), 2920 (m), 2815 (m),
1719 (s), 1665 (s), 1655 (s), 1603 (s), 1541 (s), 1509 (s),
1440 (m), 1347 (m), 1302 (m), 1020 (m), 866 (w), 702
＋
＋
(w); FAB-MS m z (rel. int.): 460 ([M Na] , 4), 439
W
7) Lazaro, E., Felix, A. S., van den Broek, L. A. G. M.,
Ottenheijm, H. C. J., and Ballesta, J. P. G., Interac-
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Antimicrob. Ag. Chemother., 10–13 (1991).
(3), 438 (MH＋, 8), 179 (43), 91 (100); FAB HRMS
m z: calcd. for C H O N S (MH＋), 438.1157;
W
19
24
5
3
2
found, 438.1148.
8) Lazaro, E., van den Broek, L. A. G. M., Felix, A. S.,
Ottenheijm, H. C. J., and Ballesta, J. P. G.,
Biochemical and kinetic characteristics of the interac-
tion of the antibiotic sparsomycin with prokaryotic
Biological Activity
Morphological reversion activity. The morphologi-
cal reversion activity on srcts-NRK cells, which were
kindly presented by Dr. Y. Uehara of National
Institute of Infectious Diseases, was assessed. The
cells were cultured in EAGLE's minimal essential
and eukaryotic ribosomes. Biochemistry
,
30,
9642–9648 (1991).
9) Theocharis, D. A., and Coutsogeorgopoulos, C.,
Mechanism of action of sparsomycin in protein
synthesis. Biochemistry, 31, 5861–5868 (1992).
medium (MEM) supplemented with 10
(CS, Hyclone Laboratories, Logan, Utah, USA) at
the permissive temperature (32 C) or at nonpermis-
sive temperature (39 C). The cells (1 10 cells ml)
maintained at 32 C were seeded into a 96-well
microtiter plate and cultured for two hours at 32
in a 5 CO2 atmosphere. Various concentrations of
z
calf serum
10) Porse, B. T., Kirillov, S. V., Awayz, M. J.,
Ottenheijm, H. C. J., and Garrett, R. A., Direct
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and Zylicz, Z., Chemical and biological aspects of
sparsomycin, an antibiotic from streptomyces.
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12) Ottenheijm, H. C. J., van Nispen, S. P. J. M., and
9
5
×
9
9
W
9
C
z
the compound solution (5 ml each) were added, and
morphological reversion of srcts-NRK cells was
observed under a microscope after 18 to 20 hours of
9
incubation at 32 C.
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Partial ˆnancial support for this research under the
Biodesign Research Program of the Institute of

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N. NAKAJIMA et al.
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,
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24) Duke, A. A., and Boots, M. R., Synthesis and
biological evaluation of sparsomycin analogues. J.
Med. Chem., 26, 1556–1561 (1983).
36)
S
S
c
c
S
s:
s:
S
S
conˆguration at the carbon and sulfur atoms.
conˆguration at the carbon and conˆgura-
R
R
25) Liskamp, R. M. J., Colstee, J. H., Ottenheijm, H. C.
J., Lelieveld, P., and Akkermann, W., Structure-
activity relationships of sparsomycin and its ana-
logues. Octylsparsomycin: The ˆrst analogue more
active than sparsomycin. J. Med. Chem., 27, 301–306
(1984).
tion at the sulfur atoms.
37) Reaction for 30 min at 0
60 min at 0 C are as follows: 17a (20
16 (41 ).
38) This compound was prepared from commercially
available 5-hydroxymethyl-6-methyluracil (Sigma) by
Dubois procedure.22)
9
C. The yields obtained after
9
z
), 17b (25 ),
z
z
26) Van den Broek, L. A. G. M., Liskamp, R. M. J.,
Colstee, J. H., Leilieveld, P., Remacha, M.,
Vazquez, D., Ballesta, J. P. G., and Ottenheijm, H.
C. J., Structure-activity relationships of sparsomycin
and its analogues. Inhibition of peptide bond forma-
tion in cell-free systems and L1210 and bacterial cell.
J. Med. Chem., 30, 325–333 (1987).
39) Carpino, L. A., 1-Hydroxy-7-azabenzotriazole. An
e‹cient peptide coupling additive. J. Am. Chem.
Soc., 115, 4397–4398 (1993).
40) ID50 values of HeLa S3 colony formation inhibition
( mM) were as follows: 19 (13.4), 20 (3.1), 21 (1.6), 3
(0.8), 4 (0.7), 5 (0.6), 6 (0.8), 7 (0.6).
27) Van den Broek, L. A. G. M., Lazaro, E., Zylicz, Z.,