Synthesis of novel guanidinoglycoside: 2-glycosylamino 4,5-dihydro-6-pyrimidinone

Full text of DOI:10.1021/jo015915q

J . Org. Chem. 2001, 66, 8243-8247
8243
Since the base’s structure of 5,6-dihydroisocytidine 3
closely resembled that of guanidinoglycosides 4, their
related literature synthetic routes were carefully stud-
ied.11 In general, the reported methods for the synthesis
of compound 3 and its base counterpart fell into four
classes: (i) hydrogenation of isocytidine counterpart over
5% rhodium-carbon;10b (ii) condensation of guanidines
with acrylates;11a (iii) reaction of guanidines with diphen-
ylcyclopropenone;11b and (iv) intramolecular cyclization
of guanidine intermediate in refluxing concentrated
hydrochloric acid.11c These methods employed fairly harsh
conditions and were restricted to a limited choice of
substituents on the pyrimidinone.
Syn th esis of Novel Gu a n id in oglycosid e:
2-Glycosyla m in o
4,5-d ih yd r o-6-p yr im id in on e
Peishan Lin, Cheng Leng Lee, and Mui Mui Sim*
Institute of Molecular and Cell Biology, 30 Medical Drive,
Singapore 117609, Singapore
mcbsimmm@imcb.nus.edu.sg
Received J uly 11, 2001
Guanidine moiety is an important feature commonly
found in many biologically active compounds.1 For ex-
ample, Streptothricin 1, one of the first actinomycete
antibiotics reported in the early 40’s,2 possesses a cyclic
guanidine moiety attached to the reducing end of a sugar
(Figure 1). Several new members of the family have been
discovered thus far.3 However, despite their broad spec-
trum of potent antimicrobial and antiviral activities, none
of them has been brought into medical use because of
cytotoxicity.4 Recently, guanidine-containing sugars have
attracted the attention of the pharmaceutical industry.
For example, Zanamivir,5 a neuraminidase inhibitor, is
now marketed as a drug for anti-influenza. Goodman has
identified some guanidinoglycosides with improved anti-
HIV activities,6 while both Wong7 and Merrer8 have
developed six- and seven-membered ring cyclic guanidine-
sugars, respectively, as new classes of transition-state
mimics of enzymatic glycosidic cleavage. Preliminary
research on glucoguanidinium derivative 2, and its
galactoguanidinium analogue has shown that they were
inhibitors of the corresponding â- and R-glycosidases.9
Similarly, 5,6-dihydroisocytidine 3 was reported in the
early 70’s to be involved in the cytosine mutagenic
process.10 However, this class of compounds was very
poorly studied during the last two decades. On the basis
of the above results, it will be of great interest to develop
novel compounds containing similar structural feature
as well as possessing the desired biological activity. A
novel class of guanidinoglycosides 4 was thus designed
and synthesized.
While searching for a milder condition for the synthesis
of guanidinoglycosides 4, we came across a report by
Pinte´r and co-workers.12 They had employed an imino-
phosphorane-based approach to generate unsymmetrical
glycosyl carbodiimides from glycosyl isothiocyanates. In
their work, one of the carbodiimides was reacted with
morpholine to yield the guanidine derivative. In view of
its mild conditions, this approach was adapted to the
synthesis of glycosyl carbodiimides in our work. The
commercially available â-glucosyl isothiocyanate was first
employed in our model study (Scheme 1). The formation
of glucosyl carbodiimide 5a proceeded smoothly and
completely in 2 h. The crude product was purified via
flash chromatography as prolonged purification time
usually led to the formation of the corresponding urea.
The addition of methyl (S)-3-amino-3-phenylpropanoate
to the purified carbodiimide 5a gave the guanidine
intermediate, which underwent spontaneous cyclization
in the presence of Et3N to yield the dihydropyrimidinone.
In theory, there are two possible cyclization pathways
for the guanidine intermediate, that is, either via the
benzylamine to give the guanidinoglycoside 4a , or via the
glycosylamine to form the guanidinoglycoside 6. In our
hands, two products corresponding to the R and â
anomers of 4a were obtained. Their structures were
1
carefully studied using H, 13C, and 2D NMR spectros-
copy. For the R-guanidinoglycoside 4a (Figure 2), 13C
NMR signal associated with C-1′ of the glucosyl residue
at 80.64 ppm was consistent with an N,O-acetal struc-
ture.13 Furthermore, its HMBC spectrum revealed cor-
related signals between CH2N-1 proton and C-2 (150.50
ppm), C-6 (167.48 ppm). No correlation was observed
between H-1′ and C-6. The same correlation was observed
for the â-guanidinoglycoside 4a , which confirmed that the
reaction proceeded solely to compound 4a . The result is
not surprising as the alkylamine is more reactive and
sterically less hindered than the glycosylamine.
* To whom correspondence should be addressed. Phone: Int. (+65)
8741443. Fax: Int. (+65) 7791117.
(1) Berlinck, R. G. S. Nat. Prod. Rep. 1999, 16, 339-365.
(2) Berlinck, R. G. S. Progress in the Chemistry of Organic Natural
Products; Springer-Verlag Wien: New York, 1995; pp 123-128.
(3) (a) Ferna´ndez-Moreno, M. A.; Vall´ın, C.; Malpartida, F. J .
Bacteriol. 1997, 179, 6929-6936. (b) Kim, B. T.; Lee, J . Y.; Lee, Y. Y.;
Kim, O. Y.; Chu, J . H.; Goo, Y. M. J . Antibiot. 1994, 47, 1333-1336.
(c) Inamori, Y.; Tominaga, H.; Okuno, M.; Sato, H.; Tsujibo H. Chem.
Pharm. Bull. 1988, 36, 1577-1580. (d) Miyashiro, S.; Ando, T.;
Hirayama, K.; Kida, T.; Shibai, H.; Murai, A.; Shiio, T.; Udaka, S. J .
Antibiot. 1983, 36, 11638-11643.
1H-15N 2D NMR experiments were also carried out to
determine the location of imino-group in compound 4a
(4) Taniyama, H.; Sawada, Y.; Kitagawa, T. Chem. Pharm. Bull.
1971, 19, 1627-1634.
(5) For a recent review, see: Gubareva, L. V.; Kaiser, L.; Hayden,
F. G. The Lancet 2000, 355, 827-835.
(11) (a) Wendelin, W.; Riedl, R. Monatsh. Chem. 1985, 116 (2), 237-
251. (b) Eicher, T.; Franke, G.; Abdesaken, F. Tetrahedron Lett. 1977,
46, 4067-4070. (c) Matsumoto, K.; Rapoport, H. J . Org. Chem. 1968,
33, 552-558. (d) Kim, Y. H.; lee, N. J . Heterocycles 1983, 20 (9), 1769-
1772.
(12) (a) Garc´ıa Ferna´ndez J . M.; Ortiz Mellet, C.; D´ıaz Pe´rez, V. M.;
Fuentes, J .; Kova´cs, J .; Pinte´r, I. Carbohydr. Res. 1997, 304, 261-
270. (b) Garc´ıa Ferna´ndez, J . M.; Ortiz Mellet, C.; D´ıaz Pe´rez, V. M.;
Fuentes, J .; Kova´cs, J .; Pinte´r, I. Tetrahedron Lett. 1997, 38, 4161-
4164.
(6) Baker, T. J .; Luedtke, N. W.; Tor, Y.; Goodman, M. J . Org. Chem.
2000, 65, 9054-9058.
(7) Wong, C.-H.; Le, V-D. J . Org. Chem. 2000, 65, 2399-2409.
(8) Merrer, Y. L.; Gauzy, L.; Gravier-Pelletier, C.; Depezay, J -C.
Bioorg. Med. Chem. 2000, 8, 307-320.
(9) Lehmann, J .; Rob, B. Tetrahedron: Asymmetry 1994, 5, 2255-
2260.
(10) (a) Skaric, V.; Matulic-Adamic, J . J . Chem. Soc., Perkin Trans.
1 1985, 779-783. (b) Skaric, V.; Gaspert, B.; Hohnjec, M. and Lacan,
G. J . Chem. Soc., Perkin Trans. 1 1974, 267-271.
(13) Chavis, C.; De Gourcy, C.; Dumont, F.; Imbach, J .-L. Carbohydr.
Res. 1983, 113, 1-20.
10.1021/jo015915q CCC: $20.00 © 2001 American Chemical Society
Published on Web 11/07/2001

8244 J . Org. Chem., Vol. 66, No. 24, 2001
Notes
F igu r e 1. Structures of guanidinoglycosides.
Sch em e 1a
a
Reagents and conditions: (a) 4-MeOOCC6H4CH2N3, PPh3, toluene, rt, 2 h; (b) MeOOCCH2CH(Ph)NH2‚HCl, Et3N, CH2Cl2, rt, 12 h.
F igu r e 2. 1H-13C HMBC correlation of compound 4a .
(R-anomer). The signal of a secondary amine at 83.79
ppm from the spectrum of 1H-15N HSQC was confirmed
as N-3. In addition, the signals observed from the
spectrum of 1H-15N HMBC (Figure 3) indicated that
there were three pairs of correlations between N-3 (83.79
ppm) and H-5a/H-5b, N-1 (152.84 ppm) and CH2N-1, as
well as N-2 (176.28 ppm) and H-1′, H-2′. This study
showed that there was no amino-imino tautomerism at
the guanidine moiety and therefore confirmed the struc-
ture of R-guanidinoglycoside 4a .
F igu r e 3. 400 MHz 1H-15N HMBC 2D NMR spectrum of
compound 4a . A solution of 80% MeNO2 in CDCl3 was used
as reference at 380 ppm.
Several different glycosyl isothiocyanates, azides, and
â-amino acid methyl esters were employed in the syn-

Notes
J . Org. Chem., Vol. 66, No. 24, 2001 8245
Ta ble 1. Gu a n id in yla tion a n d Cycliza tion P r od u cts a n d Cor r esp on d in g Ca r bod iim id es
thesis of guanidinoglycosides 4, which allowed the step-
wise introduction of substituents into the 4,5-dihydro-6-
pyrimidinone. Following the same synthetic route as
shown in Scheme 1, compounds 4b-g (Table 1) were
synthesized. The respective glycosyl isothiocyanates were
prepared according to the reported method14 by heating
glycosyl bromide15 with potassium thiocyanate in the
presence of tetrabutylammonium hydrogen sulfate. Five
carbodiimides 5a -e (Table 1) were synthesized starting
from their respective isothiocyanates by reacting with
different azides. The yield of 5b was relatively low as
compared to the other carbodiimides; this was mainly due
to the low solubility of the corresponding isothiocyanate
in the tandem aza-Wittig reaction. Carbodiimides 5a and
5c reacted readily and cyclized spontaneously upon
addition of (S)-methyl 3-amino-3-phenylpropanoate to
afford compounds 4a and 4c. Heating was required for
complete cyclization in compounds 4d -f. When (S)-
methyl 3-amino-5-phenylpentanoate was employed to
react with carbodiimide 5a , only partial cyclization
occurred to afford the dihydropyrimidinone as a minor
product. No further cyclization occurred upon heating at
80 °C in neat Et3N (data not shown). Urea formation was
observed during the guanylation of carbodiimides 5b and
5e, which might contribute to their relatively low yields.
The structure elucidations of 4b-g were also carried
out and were in accordance with the structure of 4a . It
was worth mentioning that while all the carbodiimides
5a -e retained the â configuration (J 1-2 ) 8.7-9.1 Hz),
compounds 4a -f underwent anomerization at C-1′ dur-
ing the guanylation step. Compounds 4a , 4c-f were
isolated as R and â mixtures, whereas compounds 4b was
isolated as R anomer, and compound 4g was isolated as
â anomer only. This observation was in consistent with
the Lemieux16 anomeric effect.
The seven guanidinoglycosides 4a -g were deprotected
(2 M NH3 in MeOH for 4a -f and 0.5 M NaOMe in MeOH
for 4g) and screened as R and â anomeric mixtures
against MRSA and E. coli. Although they were found to
be inactive, they were not cytotoxic up to 100 µg/mL
toward human embryonal lung MRC5 cells and human
hepatoma HuH7 cells (Streptothricin D was cytotoxic
toward 3T3 cells at 20 µg/mL).3d Little precedent exists
for the synthesis as well as the biological application of
monosaccharides with a C-1′ guanidino-moiety. The
synthetic route described herein therefore provides a
convenient and efficient way to synthesize the novel
2-glycosylamino-4, 5-dihydro-6-pyrimidinone for future
biological evaluation.
Exp er im en ta l Section
All chemicals were obtained from commercial suppliers and
used without further purification. Analytical TLC was carried
out on precoated glass plates (Merck silica gel 60, F254). Column
(14) Camarasa, M. J .; Ferna´ndez-Resa, P.; Garc´ıa-Lo´pez, M. T.; De
Las Heras, F. G.; Me´ndez-Castrillo´n, P. P.; San Felix, A. Synth.
Commun. 1984, 509-510.
(16) Boons, G.-J . Carbohydrate Chemistry, 1st ed.; Blackie Academic
and Professional: London, UK, 1998; Chapter 1.
(15) Gillard, J . W.; Israel, M. Tetrahedron Lett. 1981, 22, 513-516.

8246 J . Org. Chem., Vol. 66, No. 24, 2001
Notes
chromatography was performed with silica gel (70-230 mesh)
from Merck. All NMR spectra were recorded with a Bruker
Avance DMX 400 MHz instrument in CDCl3 solutions. Assign-
ments of R and â anomers were based on the sugar H1-H2
coupling constant. High-resolution mass spectra were deter-
mined using a Marina Biospectrometry workstation via ESI+.
The purification solvent system employed for compounds 5a -
d , 4a -f was 50% hexane in EtOAc, and for compounds 5e and
4g was 75% hexane in EtOAc. HPLC analysis was performed
with a Hewlett-Packard 1040 equipped with a Hypersil ODS C18
reverse-phase column (2.1 × 200 mm). Runs used two gradients
(A: 40% to 100% CH3CN in H2O with 0.1% of TFA; B: 30% to
100% CH3CN in H2O with 0.1% of TFA; flow rate: 0.3 mL/min
over 20 min). The HPLC purities for compounds 4a , 4b and 4d
were determined at 220 nm.
Gen er a l P r oced u r e for Com p ou n d s 4. A mixture of
glycosyl isothiocyanate (0.1-0.5 mmol) and triphenylphosphine
(1.1 equiv) in anhydrous toluene was stirred for 10 min. Azides
(1.1 equiv) was then added, and the reaction mixture was stirred
for another 2 h. The carbodiimide intermediate 5 purified on
column chromatography was redissolved in CH2Cl2, followed by
the addition of â-amino acid methyl ester hydrochloride salt (1.1
equiv with respect to compound 5) and Et3N (1.8 equiv). The
reaction mixture was stirred for 12 h, and the crude guani-
dinoglycosides 4 were purified on preparative TLC plate to yield
the R and â anomers separately.
N-[4-(Meth oxycar bon yl)ben zyl]-N′-(2,3,4,6-tetr a-O-acetyl-
â-D-glu cop yr a n osyl)ca r bod iim id e 5a (202 mg, yield 78%,
white solid): 1H NMR δ 1.90, 1.92, 1.97 (3s, 12H, COCH3), 3.68
(ddd, 1H, J ) 9.9, 4.7, 2.2 Hz, H-5), 3.81 (s, 3H, OCH3), 4.04
(dd, 1H, J ) 12.4, 2.0 Hz, H-6a), 4.14 (dd, 1H, J ) 12.4, 4.8 Hz,
H-6b), 4.41, 4.47 (ABd, 2H, J ) 15.2 Hz, CH2Ph), 4.59 (d, 1H, J
) 8.8 Hz, H-1), 4.82 (t, 1H, J ) 9.1 Hz, H-2), 4.99 (t, 1H, J ) 9.7
Hz, H-4), 5.09 (t, 1H, J ) 9.5 Hz, H-3), 7.29 (d, 2H, J ) 8.1 Hz,
4-MeOCOC6H4), 7.91 (d, 2H, J ) 8.2 Hz, 4-MeOCOC6H4); 13C
NMR δ 20.4, 20.5, 20.6, 49.4, 52.0, 61.8, 68.1, 72.8(1), 72.8(3),
73.8, 84.4, 127.1, 129.5, 129.9, 137.4, 142.3, 166.5, 169.2, 170.0,
170.4; HRMS calcd for C24H28N2O11Na (M + Na)+ 543.1593,
found 543.1596.
(S)-1-[4-(Met h oxyca r b on yl)b en zyl]-2-(2′,3′,4′,6′-t et r a -O-
a cetyl-D-glu cop yr a n osyl) a m in o-4-p h en yl-4, 5-d ih yd r o-6-
p yr im id in on e 4a (197 mg, yield 76%, R:â ) 2:1), R anomer
(white solid, 100% HPLC purity): 1H NMR δ 1.93, 1.99, 2.02,
2.05 (4s, 12H, COCH3), 2.93 (dd, 1H, J ) 16.24, 8.40 Hz, H-5a),
3.06 (dd, 1H, J ) 16.24, 4.96 Hz, H-5b), 3.44 (br d, 1H, J ) 9.72
Hz, H-5′), 3.76 (dd, 1H, J ) 12.43, 2.02 Hz, H-6a′), 3.90 (s, 3H,
OCH3), 4.04 (dd, 1H, J ) 12.39, 3.66 Hz, H-6b′), 4.65 (dd, 1H, J
) 8.10, 5.14 Hz, H-4), 4.87 (dd, 1H, J ) 10.06, 4.06 Hz, H-2′),
5.01 (t, 1H, J ) 9.70 Hz, H-4′), 5.04 (d, 1H, J ) 13.98 Hz, NCH2),
5.31 (d, 1H J ) 4.07 Hz, H-1′), 5.45 (d, 1H, J ) 14.06 Hz, NCH2),
5.65 (br s, 1H, NH), 5.68 (t, 1H, J ) 9.72 Hz, H-3′), 7.18-7.20
(m, 2H, C6H5), 7.36-7.38 (m, 3H, C6H5), 7.48 (d, 2H, J ) 8.16
Hz, 4-MeOCOC6H4), 7.99 (d, 2H, J ) 8.12 Hz, 4-MeOCOC6H4);
13C NMR δ 20.5, 20.6, 20.8, 20.9, 39.9, 43.8, 51.4, 52.0, 62.0, 67.7,
68.6, 70.5, 71.7, 80.6, 125.8, 128.9, 129.1, 129.4, 129.7, 139.1,
143.3, 150.5, 167.0, 167.5, 169.7, 170.2, 170.5, 170.6; HRMS calcd
for C33H38N3O12 (M + H)+ 668.2456, found 668.2453.
Hz, H-3), 5.50 (d, 1H, J ) 9.14 Hz, NH), 7.39 (d, 2H, J ) 8.06
Hz, C6H4), 8.00 (d, 2H, J ) 8.15 Hz, C6H4); 13C NMR δ 20.6,
20.7, 23.3, 49.5, 52.2, 56.3, 62.0, 68.2, 72.6, 73.9, 85.2, 127.1,
129.4, 129.9, 137.3, 142.5, 166.7, 169.3, 170.4, 170.7, 171.1;
HRMS calcd for C24H29N3O10Na (M + Na)+ 542.1753, found
542.1750.
(S)-1-[4-(Meth oxycar bon yl)ben zyl]-2-(2′-acetam ido-3′,4′,6′-
tr i-O-a cetyl-r-D-glu cop yr a n osyl)a m in o-4-p h en yl-4, 5-d ih y-
d r o-6-p yr im id in on e 4b (7 mg, yield 33%, R only, light brown
syrup, 100% HPLC purity): 1H NMR δ 1.62, 1.86, 1.96, 1.98 (4s,
12H, COCH3), 2.91 (dd, 1H, J ) 16.28, 7.87 Hz, H-5a), 3.06 (dd,
1H, J ) 16.29, 5.18 Hz, H-5b), 3.42 (br d, 1H, J ) 9.14 Hz, H-5′),
3.72 (dd, 1H, J ) 12.42, 2.07 Hz, H-6a′), 3.83 (s, 3H, OCH3),
4.00 (dd, 1H, J ) 12.46, 3.62 Hz, H-6b′), 4.22 (td, 1H, J ) 10.05,
3.92 Hz, H-2′), 4.65 (br t, 1H, J ) 5.92 Hz, H-4), 4.89 (d, 1H, J
) 3.88 Hz, H-1′), 5.01 (t, 1H, J ) 9.77 Hz, H-4′), 5.21 (br s, 2H,
NCH2), 5.29 (t, 1H, J ) 9.91 Hz, H-3′), 5.32 (br d, 1H, J ) 7.13
Hz, NH), 5.72 (br s, 1H, NH), 7.13-7.15 (m, 2H, aromatic), 7.27-
7.34 (m, 5H, aromatic), 7.94 (d, 2H, J ) 8.11 Hz, 4-CH3-
OCOC6H4); 13C NMR δ 20.5, 20.8, 23.1, 39.6, 44.1, 51.4, 52.1,
52.2, 62.0, 68.1, 68.3, 71.7, 82.1, 125.7, 127.6, 129.1, 129.4, 130.0,
139.0, 143.6, 151.0, 166.7, 167.5, 169.3, 169.8, 170.6, 171.5;
HRMS calcd for C33H39N4O11 (M + H)+ 667.2616, found 667.2614.
N-[2-(N-P h th a lim id o)eth yl]-N′-(2,3,4,6-tetr a -O-a cetyl-â-
D-glu cop yr a n osyl)ca r bod iim id e 5c (150 mg, yield 72%, color-
less syrup): 1H NMR δ 1.92, 1.95, 1.96, 2.01 (4s, 12H, COCH3),
3.54-3.64 (m, 2H, NCH2), 3.64-3.67 (m, 1H, H-5), 3.80-3.84
(m, 2H, NCH2), 4.01 (dd, 1H, J ) 12.49, 2.09 Hz, H-6a), 4.11
(dd, 1H, J ) 12.35, 4.81 Hz, H-6b), 4.58 (d, 1H, J ) 8.74 Hz,
H-1), 4.82 (t, 1H, J ) 9.12 Hz, H-2), 5.00 (t, 1H, J ) 9.65 Hz,
H-4), 5.08 (t, 1H, J ) 9.44 Hz, H-3), 7.68-7.71 (m, 2H, C6H4),
7.79-7.82 (m, 2H, C6H4); 13C NMR δ 20.5, 20.7, 38.4, 43.9, 61.8,
68.1, 72.6, 72.9, 73.7, 84.5, 123.4, 131.9, 134.2, 136.6, 168.0,
169.3, 170.1, 170.6; HRMS cacld for C25H27N3O11Na (M + Na)+
568.1546, found 568.1545.
(S)-1-[2-(N-P h th alim ido)eth yl]-2-(2′,3′,4′,6′-tetr a-O-acetyl-
D-glu cop yr a n osyl)a m in o-4-p h en yl-4, 5-d ih yd r o-6-p yr im i-
d in on e 4c (41 mg, yield 65%, R:â ) 1:1), R anomer (light yellow
syrup): 1H NMR δ 2.03, 2.04, 2.05, 2.08 (4s, 12H, COCH3), 2.64-
2.68 (m, 2H, H-5), 4.02 (dd, 1H, J ) 12.48, 1.96 Hz, H-6a′), 4.13-
4.17 (m, 3H, H-5′, NCH2), 4.28 (dd, 2H, J ) 12.15, 3.46 Hz,
H-6b′), 4.22-4.29 (m, 1H, NCH2), 4.42 (ddd, 1H, J ) 13.32, 6.78,
2.89 Hz, NCH2), 4.54 (dd, 1H, J ) 10.19, 5.69 Hz, H-4), 4.94
(dd, 1H, J ) 10.03, 4.19 Hz, H-2′), 5.11 (t, 1H, J ) 9.76 Hz, H-4′),
5.32 (d, 1H, J ) 4.10 Hz, H-1′), 5.61 (br s, 1H, NH), 5.67 (t, 1H,
J ) 9.65 Hz, H-3′), 7.30 (d, 2H, J ) 6.62 Hz, C6H5), 7.37-7.43
(m, 3H, C6H5), 7.69-7.72 (m, 2H, phthalimide), 7.82-7.85 (m,
2H, phthalimide); 13C NMR δ 20.7(0), 20.7(1), 20.7(7), 20.8, 36.3,
40.0, 40.1, 51.6, 62.2, 67.8, 68.7, 70.8, 71.7, 81.0, 123.2, 126.2,
129.1, 129.4, 132.1, 133.9, 138.8, 150.8, 168.2, 168.6, 169.8, 170.2,
170.5, 170.7; HRMS calcd for C34H37N4O12 (M + H)+ 693.2409,
found 693.2409. Anal. Calcd for C34H36N4O12 (692.2): C, 58.96;
H, 5.24; N, 8.09. Found: C, 57.24; H, 5.56; N, 7.78.
â anomer: 1H NMR δ 1.26, 1.92, 1.93, 1.98 (4s, 12 H, COCH3),
2.48 (dd, 1H, J ) 16.01, 12.47 Hz, H-5a), 2.68 (dd, 1H, J ) 15.98,
2.20 Hz, H-5b), 3.51 (t, 1H, J ) 8.56 Hz, H-5′), 3.58 (dd, 1H, J
) 11.69, 7.90 Hz, H-6a′), 3.82-3.86 (m, 1H, NCH2), 3.89 (d, 1H,
J ) 11.39 Hz, H-6b′), 3.93-3.97 (m, 1H, NCH2), 3.98-4.03 (m,
1H, NCH2), 4.26-4.31 (m, 1H, NCH2), 4.49 (t, 1H, J ) 9.68 Hz,
H-4′), 4.55 (t, 1H, J ) 8.72 Hz, H-1′), 4.57-4.61 (m, 1H, H-4),
4.63 (t, 1H, J ) 9.06 Hz, H-2′), 5.07 (t, 1H, J ) 9.46 Hz, H-3′),
5.76 (br s, 1H, NH), 7.26-7.34 (m, 5H, C6H5), 7.65-7.67 (m, 2H
phthalimide), 7.77-7.80 (m, 2H, phthalimide); 13C NMR δ 19.6,
20.6, 20.7, 20.8, 36.9, 40.0, 40.8, 52.0, 62.9, 68.7, 72.7, 72.8, 73.5,
85.9, 123.2, 125.9, 128.7, 129.3, 132.5, 133.8, 140.4, 151.8, 167.8,
168.6, 169.2, 169.6, 170.3, 170.5.
(S)-1-[2-(N-P h th alim ido)eth yl]-2-(2′,3′,4′,6′-tetr a-O-acetyl-
D-glu cop yr a n osyl)a m in o-4-(2-th ien yl)-4,5-d ih yd r o-6-p yr i-
m id in on e 4d (47 mg, yield 73%, R:â ) 1:1), R anomer (light
yellow syrup, 91% and 100% HPLC purity in A and B solvent
systems, respectively): 1H NMR δ 1.99, 2.02, 2.07, 2.11 (4s, 12H,
COCH3), 2.32 (dd, 1H, J ) 16.01, 10.04 Hz, H-5a), 2.57 (dd, 1H,
J ) 16.01, 4.16 Hz, H-5b), 2.67 (dd, 1H, J ) 13.90, 9.26 Hz, CH2
of thienyl), 2.82 (dd, 1H, J ) 13.95, 4.44 Hz, CH2 of thienyl),
3.55-3.61 (m, 1H, H-4), 3.63 (dd, 1H, J ) 12.47, 1.28 Hz, H-6a′),
4.02-4.13 (m, 4H, H-5′, H-6b′, NCH2), 4.27-4.29 (m, 2H, NCH2),
4.91 (dd, 1H, J ) 10.02, 4.24 Hz, H-2′), 5.07 (t, 1H, J ) 9.77 Hz,
â anomer (colorless syrup): 1H NMR δ 1.40, 1.73, 1.92, 1.95
(4s, 12H, COCH3), 2.68 (dd, 1H, J ) 16.22, 10.78 Hz, H-5a), 2.86
(dd, 1H, J ) 16.38, 4.38 Hz, H-5b), 3.68-3.72 (m, 1H, H-5′), 3.83
(s, 3H, OCH3), 3.85 (dd, 1H, J ) 12.60, 7.25 Hz, H-6a′), 4.05 (d,
1H, J ) 10.80 Hz, H-6b′), 4.62 (br d, 1H, J ) 7.34 Hz, H-4), 4.75
(d, 1H, J ) 8.65 Hz, H-1′), 4.90 (t, 1H, J ) 9.72 Hz, H-4′), 4.99
(d, 1H, J ) 14.53 Hz, NCH2), 5.06 (t, 1H, J ) 9.21 Hz, H-2′),
5.09 (d, 1H, J ) 15.13 Hz, NCH2), 5.19 (t, 1H, J ) 9.52 Hz, H-3′),
5.98 (s, 1H, NH), 7.24-7.33 (m, 7H, aromatic), 7.86 (d, 2H, J )
8.18 Hz, 4-MeOCOC6H4); 13C NMR δ 19.8, 20.6, 40.6, 44.0, 51.8,
52.0, 62.7, 68.7, 72.5, 73.0, 73.9, 86.3, 125.8, 128.1, 128.8, 129.3,
129.5, 140.0, 143.1, 151.3, 167.3, 169.4, 169.5, 170.3, 170.5.
N-[4-(Met h oxyca r b on yl)b en zyl]-N′-(2-a cet a m id o-3,4,6-
tr i-O-a cetyl-â-D-glu cop yr a n osyl)ca r bod iim id e 5b (47 mg,
53%, light yellow solid): 1H NMR δ 1.92, 2.03, 2.08 (3s, 12H,
COCH3), 3.72 (ddd, 1H, J ) 9.72, 4.54, 2.33 Hz, H-5), 3.91 (s,
3H, OCH3), 3.96 (t, 1H, J ) 9.70 Hz, H-2), 4.14 (dd, 1H, J )
12.15, 1.58 Hz, H-6a), 4.23 (dd, 1H, J ) 12.30, 4.81 Hz, H-6b),
4.52, 4.59 (ABd, 2H, J ) 15.10 Hz, NCH2), 4.71 (d, 1H, J ) 9.09
Hz, H-1), 5.06 (t, 1H, J ) 9.63 Hz, H-4), 5.17 (t, 1H, J ) 9.86

Notes
J . Org. Chem., Vol. 66, No. 24, 2001 8247
H-4′), 5.31 (d, 1H, J ) 4.20 Hz, H-1′), 5.59 (t, 1H, J ) 9.67 Hz,
H-3′), 5.63 (s, 1H, NH), 6.92 (d, 1H, J ) 4.78 Hz, thiophene),
7.09 (br s, 1H, thiophene), 7.35 (dd, 1H, J ) 4.72, 2.99 Hz,
thiophene), 7.68-7.72 (m, 2H, phthalimide), 7.80-7.82 (m, 2H,
phthalimide); 13C NMR δ 20.7, 20.8(0), 20.8(1), 20.9, 35.9, 36.2,
37.4, 39.6, 48.2, 62.1, 67.6, 68.6, 70.7, 71.8, 80.8, 123.1, 123.2,
127.2, 127.6, 132.0, 133.9, 136.1, 150.7, 168.1, 168.5, 169.7, 170.1,
170.5, 170.8; HRMS calcd for C33H37N4O12S (M + H)+ 713.2130,
found 713.2131.
1H, J ) 16.24, 9.64 Hz, H-5a), 2.51 (dd, 1H, J ) 13.67, 9.33 Hz,
CH2C6H4), 2.76 (dd, 1H, J ) 13.25, 4.68 Hz, CH2C6H4), 2.77 (dd,
1H, J ) 16.55, 3.30 Hz, H-5b), 3.02 (br d, 1H, J ) 10.08 Hz,
H-5′), 3.24 (dd, 1H, J ) 12.39, 2.84 Hz, H-6a′), 3.52-3.58 (m,
1H, H-4), 3.80 (dd, 1H, J ) 12.37, 3.41 Hz, H-6b′), 4.74 (dd, 1H,
J ) 10.22, 4.22 Hz, H-2′), 4.79 (d, 1H, J ) 13.95 Hz, NCH2),
4.86 (t, 1H, J ) 9.75 Hz, H-4′), 5.14 (d, 1H, J ) 4.15 Hz, H-1′),
5.20 (d, 1H, J ) 13.92 Hz, NCH2), 5.42 (br s, 1H, NH), 5.48 (t,
1H, J ) 9.74 Hz, H-3′), 6.96 (d, 2H, J ) 8.31 Hz, 4-ClC6H4),
7.20 (d, 2H, J ) 7.51 Hz, 4-ClC6H4), 7.24 (d, 2H, J ) 8.27 Hz,
4-ClC6H4), 7.30 (d, 2H, J ) 8.36 Hz, 4-ClC6H4); 13C NMR δ 20.6,
20.7, 20.8, 20.9, 37.8, 41.0, 43.4, 48.8, 62.0, 67.2, 68.6, 70.4, 71.8,
80.6, 128.5, 129.3, 130.2, 130.3, 132.8, 133.5, 134.1, 136.7, 150.5,
167.6, 169.7, 170.2, 170.4; HRMS calcd for C32H36Cl2N3O10 (M
+ H)+ 692.1779, found 692.1775. Anal. Calcd for C23H35Cl2N3O10
(691.2): C, 55.50; H, 5.09; N, 6.07. Found: C, 55.18; H, 5.41; N,
5.97.
â anomer (colorless syrup): 1H NMR δ 1.97, 2.00, 2.06 (3s,
12H, COCH3), 2.40 (dd, 1H, J ) 15.95, 10.01 Hz, H-5a), 2.58
(dd, 1H, J ) 15.93, 3.61 Hz, H-5b), 2.79 (dd, 1H, J ) 14.36, 8.62
Hz, CH2 of thienyl), 2.87 (dd, 1H, J ) 14.24, 5.38 Hz, CH2 of
thienyl), 3.38-3.41 (m, 1H, H-5′), 3.63-3.70 (m, 1H, H-4), 3.80-
3.84 (m, 1H, NCH2), 3.91-4.03 (m, 4H, NCH2, H-6a′, H-6b′),
4.04-4.17 (m, 1H, NCH2), 4.27 (d, 1H, J ) 8.66 Hz, H-1′), 4.71
(t, 1H, J ) 9.19 Hz, H-2′), 4.79 (t, 1H, J ) 9.76 Hz, H-4′), 5.01
(t, 1H, J ) 9.57 Hz, H-3′), 5.42 (br s, 1H, NH), 6.92 (d, 1H, J )
4.69 Hz, thiophene), 7.07 (br s, 1H, thiophene), 7.30 (dd, 1H, J
) 4.48, 3.13 Hz, thiophene), 7.63-7.66 (m, 2H, phthalimide),
7.75-7.77 (m, 2H, phthalimide); 13C NMR δ 20.6(5), 20.6(9), 20.7,
20.9, 35.6, 36.5, 37.8, 39.9, 47.5, 62.4, 68.5, 72.4, 73.1, 73.3, 86.5,
122.8, 123.3, 127.0, 127.9, 132.3, 133.8, 136.4, 150.8, 168.4, 168.6,
169.3, 169.5, 170.4, 170.5.
N-(4-Ch lor oben zyl)-N′-(2,3,4,6-tetr a-O-acetyl-â-D-glu copy-
r a n osyl)ca r b od iim id e 5d (128 mg, yield 63%, colorless
syrup): 1H NMR δ 1.97, 1.99, 2.05 (3s, 12H, COCH3), 3.72 (ddd,
1H, J ) 9.88, 4.73, 2.23 Hz, H-5), 4.10 (dd, 1H, J ) 12.37, 2.09
Hz, H-6b), 4.21 (dd, 1H, J ) 12.36, 4.82 Hz, H-6a), 4.38, 4.44
(ABd, 2H, J ) 14.81 Hz, CH2Ph), 4.61 (d, 1H, J ) 8.83 Hz, H-1),
4.87 (t, 1H, J ) 9.11 Hz, H-2), 5.05 (t, 1H, J ) 9.68 Hz, H-4),
5.15 (t, 1H, J ) 9.46 Hz, H-3), 7.21 (d, 2H, J ) 8.39 Hz, C6H4),
7.29 (d, 2H, J ) 8.35 Hz, C6H4); 13C NMR δ 20.6(0), 20.6(3), 20.7,
49.2, 61.9, 68.1, 72.8, 72.9, 73.8, 84.5, 128.7, 128.8, 133.5, 135.8,
137.6, 169.4, 170.2, 170.6; HRMS calcd for C22H25ClN2O9Na (M
+ Na)+ 519.1149, found: 519.1145.
â anomer (colorless syrup): 1H NMR δ 1.83, 2.02, 2.05, 2.06
(4s, 12H, COCH3), 2.54 (dd, 1H, J ) 16.09, 8.60 Hz, H-5a), 2.73
(dd, 1H, J ) 16.06, 4.32 Hz, H-5b), 2.76 (dd, 1H, J ) 13.66, 8.18
Hz, CH2C6H4), 2.82 (dd, 1H, J ) 13.72, 6.31 Hz, CH2C6H4), 3.61
(ddd, 1H, J ) 10.08, 4.90, 2.68 Hz, H-5′), 3.65-3.68 (m, 1H, H-4),
4.05 (dd, 1H, J ) 12.37, 4.92 Hz, H-6′a), 4.10(dd, 1H, J ) 12.37,
2.64 Hz, H-6′b), 4.60 (d, 1H, J ) 8.55 Hz, H-1′), 4.88 (d, 1H, J )
14.24 Hz, NCH2), 5.04 (d, 1H, J ) 14.32 Hz, NCH2), 5.04 (t, 1H,
J ) 9.61 Hz, H-4′), 5.11 (t, 1H, J ) 9.12 Hz, H-2′), 5.20 (t, 1H,
J ) 9.40 Hz, H-3′), 5.68 (br s, 1H, NH), 7.11 (d, 2H, J ) 8.35
Hz, 4-ClC6H4), 7.22 (d, 2H, J ) 8.61 Hz, 4-ClC6H4), 7.26 (d, 2H,
J ) 8.55 Hz, 4-ClC6H4), 7.33 (d, 2H, J ) 8.32 Hz, 4-ClC6H4); 13
C
NMR δ 20.6, 20.8, 37.6, 40.7, 43.3, 48.4, 62.4, 68.6, 72.4, 73.1,
73.8, 86.7, 128.3, 129.2, 129.9, 130.4, 132.8, 133.5, 134.4, 136.5,
150.4, 167.6, 169.3, 169.4, 170.3, 170.4.
N-[4-(Meth oxyca r bon yl)ben zyl]-N′-(2,3,5-tr iben zoyl-â-D-
r ibofu r a n osyl)ca r bod iim id e 5e (66 mg, yield 80%, white
solid): 1H NMR δ 3.82 (s, 3H, OCH3), 4.41 (d, 2H, J ) 3.84 Hz,
NCH2), 4.45-4.48 (m, 1H, H-5a), 4.59-4.65 (m, 2H, H-4, H-5b),
5.47 (d, 1H, J ) 4.32 Hz, H-2), 5.48 (s, 1H, H-1), 5.71 (dd, 1H,
J ) 6.16, 4.45 Hz, H-3), 7.24-7.34 (m, 11H, aromatic), 7.82 (d,
2H, J ) 7.55 Hz, aromatic), 7.89-7.92 (m, 4H, aromatic), 8.00
(d, 2H, J ) 7.52 Hz, aromatic); 13C NMR δ 49.3, 51.9, 64.2, 71.6,
76.6, 79.0, 89.5, 127.0, 128.4, 128.5, 128.7, 128.9, 129.4, 129.5,
129.7, 129.8, 129.9, 133.2, 133.5, 133.6, 138.4, 142.3, 165.0, 165.1,
166.0, 166.6; HRMS calcd for C36H30N2O9Na (M + Na)+ 657.1851,
found 657.1856.
(S)-1-[4-(Meth oxyca r bon yl)ben zyl]-2-(2′,3′,5′-tr iben zoyl-
â-D-r ibofu r a n osyl)a m in o-4-p h en yl-4, 5-d ih yd r o-6-p yr im i-
d in on e 4g (20 mg, yield 35%, light yellow solid, mp 165-168
°C, â only): 1H NMR δ 2.71 (dd, 1H, J ) 16.16, 9.44 Hz, H-5a),
2.78 (dd, 1H, J ) 16.26, 4.75 Hz, H-5b), 3.76 (s, 3H, OCH3), 4.29
(dd, 1H, J ) 11.40, 5.09 Hz, H-5a′), 4.46-4.54 (m, 2H, H-4′,
H-5b′), 4.56-4.59 (m, 1H, H-4), 4.91, 5.00 (ABd, 2H, J ) 14.37
Hz, NCH2), 5.46 (s, 1H, H-1′), 5.56 (d, 1H, J ) 4.50 Hz, H-2′),
5.68 (dd, 1H, J ) 7.00, 4.60 Hz, H-3′), 6.10 (s, 1H, NH), 7.04-
7.54 (m, 16H, aromatic), 7.86 (d, 4H, J ) 8.04 Hz, aromatic),
7.91 (d, 4H, J ) 7.62 Hz, aromatic); 13C NMR δ 39.8, 43.7, 51.4,
51.9, 64.5, 72.6, 77.5, 78.3, 91.0, 126.1, 128.3, 128.4(0), 128.4-
(3), 128.5, 128.8, 129.0, 129.3, 129.6(0), 129.6(1), 129.7, 129.8,
133.2, 133.4, 133.5, 139.5, 143.2, 149.7, 165.4, 165.8, 166.1, 167.0,
167.6; HRMS calcd for C45H40N3O10 (M + H)+ 782.2715, found
782.2716. Anal. Calcd for C45H39N3O10 (781.3): C, 69.13; H, 5.03;
N, 5.37. Found: C, 68.63; H, 5.14; N, 5.00.
(S)-1-(4-Ch lor oben zyl)-2-(2′, 3′, 4′, 6′-tetr a -O-a cetyl-D-
glu cop yr a n osyl)a m in o-4-(2-th ien yl)-4,5-d ih yd r o-6-p yr im i-
d in on e 4e (39 mg, yield 49%, R:â ) 8:1) R anomer (colorless
syrup): 1H NMR δ 1.95, 1.96(2), 1.96(5), 1.97 (4s, 12H, COCH3),
2.46 (dd, 1H, J ) 16.14, 10.50 Hz, H-5a), 2.60 (dd, 1H, J ) 13.95,
9.21 Hz, CH2 of thienyl), 2.77 (dd, 1H, J ) 16.14, 3.10 Hz, H-5b),
2.83 (dd, 1H, J ) 13.92, 4.52 Hz, CH2 of thienyl), 3.01 (br d, 1H,
J ) 9.82 Hz, H-5′), 3.31 (dd, 1H, J ) 12.30, 2.88 Hz, H-6a′),
3.55-3.59 (m, 1H, H-4), 3.75 (dd, 1H, J ) 12.29, 3.51 Hz, H-6b′),
4.75 (dd, 1H, J ) 10.18, 4.19 Hz, H-2′), 4.80 (d, 1H, J ) 13.98
Hz, NCH2), 4.87 (t, 1H, J ) 9.75 Hz, H-4′), 5.15 (d, 1H, J ) 4.12
Hz, H-1′), 5.20 (d, 1H, J ) 13.94 Hz, NCH2), 5.47 (br s, 1H, NH),
5.47 (t, 1H, J ) 9.70 Hz, H-3′), 6.80 (dd, 1H, J ) 5.62, 0.91 Hz,
thiophene), 6.97 (d, 1H, J ) 1.92 Hz, thiophene), 7.20 (d, 2H, J
) 8.65 Hz, 4-ClC6H4), 7.26 (dd, 1H, J ) 4.87, 2.98 Hz, thiophene),
7.30 (d, 2H, J ) 8.33 Hz, 4-ClC6H4); 13C NMR δ 20.6, 20.7, 20.8,
20.9, 36.0, 37.9, 43.4, 48.3, 62.3, 67.1, 68.8, 70.4, 71.7, 80.6, 123.1,
127.4, 127.6, 128.5, 130.2, 132.6, 135.8, 136.7, 150.5, 167.8, 169.7,
170.2, 170.4, 170.5; HRMS calcd for C30H35ClN3O10S (M + H)+
664.1732, found 664.1730. Anal. Calcd for C30H34ClN3O10
S
(663.2): C, 54.26; H, 5.16; N, 6.33. Found: C, 53.59; H, 5.29; N,
6.16.
â anomer (colorless syrup): 1H NMR δ 1.75, 1.95, 1.98, 2.00
(4s, 12H, COCH3), 2.48 (dd, 1H, J ) 16.18, 9.71 Hz, H-5a), 2.70
(dd, 1H, J ) 16.05, 4.59 Hz, H-5b), 2.74 (dd, 1H, J ) 13.79, 8.03
Hz, CH2 of thienyl), 2.86 (dd, 1H, J ) 14.07, 5.10 Hz, CH2 of
thienyl), 3.52-3.55 (m, 1H, H-5′), 3.60-3.64 (m, 1H, H-4), 4.00
(dd, 1H, J ) 12.35, 2.10 Hz, H-6a′), 4.05 (dd, 1H, J ) 12.25,
4.96 Hz, H-6b′), 4.46 (d, 1H, J ) 8.30 Hz, H-1′), 4.81 (d, 1H, J )
14.26 Hz, NCH2), 4.99 (d, 1H, J ) 14.45 Hz, NCH2), 5.00 (t, 1H,
J ) 9.39 Hz, H-4′), 5.06 (t, 1H, J ) 9.04 Hz, H-2′), 5.12 (t, 1H,
J ) 9.38 Hz, H-3′), 5.50 (br s, 1H, NH), 6.89 (d, 1H, J ) 4.74
Hz, thiophene), 7.03 (br s, 1H, thiophene), 7.15 (d, 4H, J ) 8.42
Hz, C6H4), 7.19 (d, J ) 8.26 Hz, C6H4), 7.31 (dd, 1H, J ) 4.65,
2.96 Hz, thiophene); 13C NMR δ 20.4, 20.5, 20.6, 35.5, 37.8, 43.0,
47.4, 62.1, 68.3, 72.2, 73.0, 73.4, 86.4, 122.8, 127.0, 127.6, 128.1,
128.7, 129.7, 135.9, 136.3, 150.8, 167.6, 169.1, 169.2, 170.2, 170.3.
(S)-1-(4-Ch lor oben zyl)-2-(2′,3′,4′,6′-tetr a -O-a cetyl-r-D-glu -
cop yr a n osyl)a m in o-4-(4-ch lor oben zyl)-4,5-d ih yd r o-6-p yr i-
m id in on e 4f (45 mg, yield 59%, R:â ) 3:1) R anomer (colorless
syrup): 1H NMR δ 1.94, 1.96, 1.97 (3s, 12H, COCH3), 2.47 (dd,
Ack n ow led gm en t. This work was supported by
grants from the National Science and Technology Board
of Singapore. We are grateful to Dr. Haishan Wang for
his assistance in 2D-NMR experiments, Dr. Siew Bee
Ng for carrying out the biological assays at the Center
for Natural Product Research in Singapore, and Mr.
Masafumi Inoue for performing the cytotoxicity test.
Su p p or tin g In for m a tion Ava ila ble: 1H NMR, 13C NMR
for compounds 4 (all R anomers and â anomers of compounds
4c and 4e) and 5. This material is available free of charge via
the Internet at http://pubs.acs.org..
J O015915Q