Convenient synthesis and evaluation of glycosidase inhibitory activity of α- And β-galactose-type valienamines, and some N-alkyl derivatives

Article abstract of DOI:10.1016/j.bmc.2003.12.016

Valienamine analogues having α- and β-galactose-type structures were synthesized by racemic modification from (1SR,2RS,3SR)-6-methylenecyclohex- 4-ene-1,2,3-triol. Four N-alkyl derivatives of the β-anomer were readily prepared selectively by treatment of

Full text of DOI:10.1016/j.bmc.2003.12.016

Bioorganic & Medicinal Chemistry 12 (2004) 995–1002
Convenient synthesis and evaluation of glycosidase inhibitory
activity of ꢀ- and ꢁ-galactose-type valienamines, and some
N-alkyl derivatives
Seiichiro Ogawa,a,* Yuko Sakata,a Naoyuki Ito,a Maiko Watanabe,a Kazuya Kabayama,a
Masayoshi Itohb and Takashi Korenagab
aDepartment of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Hiyoshi, Kohoku-ku,
Yokohama, 223-8522 Japan
bDepartment of Chemistry, Tokyo Metropolitan University, Minami-Ohsawa, Hachioji, Tokyo, 192-0397 Japan
Received 17 November 2003; accepted 11 December 2003
Abstract—Valienamine analogues having a- and b-galactose-type structures were synthesized by racemic modification from
(1SR,2RS,3SR)-6-methylenecyclohex-4-ene-1,2,3-triol. Four N-alkyl derivatives of the b-anomer were readily prepared selectively
by treatment of key intermediate 2,6-di-O-acetyl-3,4-O-isopropylidene-5a-carba-a- and b-l-arabino-hex-5(5a)-enopyranosyl bro-
mides with alkyl amines. All compounds were assayed for inhibitory activity against six glycosidases, and the N-dodecyl derivative
was shown to be a very strong inhibitor of b-galactosidase (IC50 0.01 mM, bovine liver).
# 2004 Elsevier Ltd. All rights reserved.
1. Introduction
1] and glucose-type N-octyl-b-valienamine4,5 [N-octyl-b-
d-5aCGlc(5,5a)enamine, GlcX 2] for b-galactosidase
and b-glucosidase, respectively (Fig. 1). Compound 1
was actually demonstrated3 to be a very potent inhibitor
of human b-galactosidase (IC50=0.3 mM), and has been
extensively studied as a candidate novel therapeutic
agent for treatment of several human genetic diseases.
Thus, such unsaturated 5a-carba-sugars are now regar-
ded as important lead compounds.
Mutant forms of enzyme proteins have been shown to
be labile and rapidly degraded in somatic cells from
patients with lysosomal storage diseases.1 However,
they can be stabilized and transported to the lysosomes
by competitive inhibitors of low molecular weight (che-
mical chaperones) for therapeutic purposes. This phe-
nomenon was confirmed for the mutant enzyme causing
Fabry disease (a-galactosidase deficiency),2 and very
recently this strategy has been extended to two other
diseases involving b-galactosidase deficiency in the central
nervous system: GM1-gangliosidosis and Morquio B
disease. Some unsaturated carbaglycosylamine deriva-
tives have recently been found with remarkable effects:
galactose-type3 [N-octyl-b-d-5aCGal(5,5a)enamine,y GalX
2. Results and discussion
We report here a sequence worked out by modification
of the route6 for 5a-carba-a-fucopyranosylamines7 with
nucleophilic substitution of the primary bromo group of
2,3,4-tri-O-acetyl-6-bromo-6-deoxy-5a-carba-a- and b-
dl-arabino-hex-5(5a)-enopyranosyl bromides{ (5ꢀ,ꢁ),
derived from the alkadiene8 4 (Scheme 1). Selective
preparation of 4 was also here achieved in a 72% yield
* Corresponding author. Tel.: +81-045-566-1559; fax: +81-045-566-
1551; e-mail: ogawa@bio.keio.ac.jp
For convenience, we herewith propose abbreviations for naming the
y
carba sugar and unsaturated carba sugars as follows: 5a-Carba-a-d-
glucopyranose: a-d-5aCGlc; 2-Acetamido-2-deoxy-5a-carba-a-d-glu-
copyranose: a-d-5aCGlcNAc; 5a-Carba-a-d-glucopyranosylamine
(validamine): a-d-5aCGlcamine; 5a-Carba-a-d-xylo-hex-(5,5a)-eno-
pyranosylamine (valienamine): a-d-5aCGlc(5,5a)enamine not b-l-
5aCIdo(5,5a)enamine. As exemplified above, the (5,5a)-unsaturated
5a-carba-sugar is a named derivative of the parent d-hexopyranose.
{
In the text use of carba-sugar nomenclature following the IUPAC-
IUBMB Nomenclature of Carbohydrates (Recommendation 1996:
Carbohydr. Res., 1997, 297, 1-92) is discussed. However, in the
experimental section, IUPAC nomenclature for bi- and tri-cyclic
compounds was used throughout for the sake of general under-
standing.
0968-0896/$ - see front matter # 2004 Elsevier Ltd. All rights reserved.
doi:10.1016/j.bmc.2003.12.016

996
S. Ogawa et al. / Bioorg. Med. Chem. 12 (2004) 995–1002
by treatment of (1SR,2SR,3RS,4SR,6RS)-1,2,3-triace-
toxy-4-bromo-6-(bromomethyl)cyclohexane8 with sodium
acetate in HMPA at 120 ꢀC.
Treatment of 4 with a slight excess of bromine in carbon
tetrachloride gave a 90% yield of approximately 1:1
mixture of the 1,4-addition products. The mixture was
separable by silica gel chromatography to afford the
dibromides8 5ꢀ and 5ꢁ. Compound 5ꢀ was treated
with sodium acetate to give a mixture of 2,3,4,6-tetra-
O-acetyl-5a-carba-dl-arabino-hex-5(5a)-enopyranosyl
bromides (6ꢀ,ꢁ). These results suggest that, although
the allylic secondary bromo group remains unchanged,
epimerization at C-1 occurs through nucleophilic attack
by bromide ions generated in situ. Therefore, the mix-
ture of 5ꢀ,ꢁ was directly converted into the bromides
6ꢀ,ꢁ, which was without purification treated with
sodium azide in DMF at room temperature to give an
inseparable 1:1 mixture of the azides8 7ꢀ,ꢁ in 85%
yield. In this case, neighboring group participation by
the 2-acetoxyl group at C-1 was first anticipated to give
rise to the b-azide 7ꢁ selectively through formation of
an intermediate 1,2-acetoxonium ion. However, the
allylic carbon atom seems sufficiently active to suffer
rear-side attack by an azide anion. Therefore, the mix-
ture of 6ꢀ,ꢁ was treated with sodium azide for conver-
sion into a mixture of 7ꢀ,ꢁ (85%), which was
subsequently subjected to reduction with triphenylphos-
phine to generate free bases. The free bases were then
converted into the N-acetyl and penta-N,O-acetyl deriv-
atives in the usual manner. However, none of the above
anomeric pairs could be separated by conventional silica
gel chromatography.
Figure 1.
O-Deacetylation of 7ꢀ,ꢁ under Zemplen conditions
gave the tetrols 9ꢀ,ꢁ, which were treated with 2,2-
dimethoxypropane-TsOH in DMF to afford, after acet-
ylation, a mixture of the 2,3-O-isopropylidene deriv-
atives 8ꢀ,ꢁ selectively. These compounds were found to
be separable on a silica gel column with 1:6 EtOAc/
hexane as an eluent, giving 8ꢀ (40%) and 8ꢁ (42%), the
1H NMR spectra of which showed a doublet of doublets
(d 4.25, J=3.8 and 4.1 Hz) and a broad doublet (d 3.97,
J=8.9 Hz) due to the pseudo-equatorial and axial pro-
tons on carbon atoms attached to the azido functions,
respectively, supporting the proposed structures.
Removal of the acetyl and isopropylidene groups of 8ꢀ
and 8ꢁ was effected by treatment with 4 M hydrochloric
acid at reflux temperature to give the respective azides
9ꢀ (80%) and 9ꢁ (74%). Reduction of the azido group
of 9ꢀ and 9ꢁ with triphenylphosphine in 70% aqueous
THF afforded, after purification over a column of
Dowex 50 Wꢁ2 (H+) resin with 5% aqueous NH3 as
eluent, the free amines9 3ꢀ and 3ꢁ in 86 and 86%
yields, respectively. Their structures were further ver-
1
ified with 13C and H NMR spectra of the respective
penta-N,O-acetyl derivatives10 10ꢀ and 10ꢁ obtained
by conventional acetylation.
Scheme 1. Reagents and conditions: (a) Br2 (molar equiv), CCl4, 1 h,
rt; (b) NaOAc (molar equiv), DMF, 20 h, rt; (c) NaN3, DMF, r.t,; (d)
1M NaOMe-MeOH, 1 h, rt; (MeO)2CMe2;, DMF, TsOH hydrate, 1
day, rt; Ac2O, pyridine; (e) 4 M HCl:THF (1:1), 1 h, reflux; f) Ph3P (3
molar equiv), 50% aq THF, 1 day, rt; Dowex 50 Wꢁ2 (H+) resin, 1%
aq NH3; g) Ac2O, pyridine.
Incorporation of an alkylamino function at C-1 of the
allyl bromides 6ꢀ,ꢁ was attempted by treatment with
an excess of n-octylamine. However, a complex mixture
of products was formed. Then, the two cis-hydroxyl

S. Ogawa et al. / Bioorg. Med. Chem. 12 (2004) 995–1002
997
groups of 6ꢀ,ꢁ were protected, with the aim of restrict-
ing conformational flexibility and avoiding a possible
participation of the 4-hydroxyl (Scheme 2). Thus,
the optically pure diene8,11 D-4 was first converted into the
3,4-O-isopropylidene derivative 11, which was subse-
quently treated with bromine to afford the 1,4-addition
products, ca. 1.7:1 mixture (76%) of 12ꢀ and 12ꢁ.
Treatment of 12ꢀ,ꢁ with sodium acetate gave selec-
tively a mixture of the bromides 13ꢀ,ꢁ, which was
separable by silica gel chromatography, affording 13ꢀ
(48%) and 13ꢁ (23%). The 1H NMR signals due to C-1
appeared as a doublet of doublets (d 4.83, J=3.9 and
7.7 Hz) and a broad doublet (d 4.50, J 8.3 Hz), respec-
tively. Reaction of the a-bromide 13ꢀ with 4 molar
equivof octylamine proceeded smoothly in an S N2
fashion to give the protected N-octyl derivative as a
single b-amine 15 (68%), which was then treated with
aqueous acetic acid and subsequently purified on a col-
umn of Dowex 50Wꢁ2 (H+) resin with aqueous
ammonia, affording 13 (56%). Similar treatment with
hexyl-, decyl- and dodecyl-amines produced the corres-
ponding N-alkyl derivatives12 14, 16, and 17, which
were deprotected to provide the b-amines 18, 19, and 20
in 30–65% total yields.
sole products, conceivably through neighboring group
participation with the 2-acetoxyl or hydroxyl group
(Scheme 3). Therefore, synthesis of 1 and its analogues
would be much improved by use of an intact mixture of
13ꢀ,ꢁ as the starting material.
It is interesting to note that, on treatment with alkyl
amines, the b-bromide 13ꢁ also gave the b-amines as
Scheme 3.
3. Biological assay
Results of biological assays13 for inhibitory activity
toward several glycohydrolases are listed in Table 1.
None of the compounds showed any inhibitory activity
against a-fucosidase (bovine kidney), a-glucosidase
(Baker’s yeast), or a-mannosidase (Jack beans). Although,
for synthetic reasons,3 only the N-octyl derivative 1 of
3ꢁ has so far received attention as a b-galactosidase
inhibitor, the present work provides the first description
of inhibitory activity against glycohydrolases obtained
by a series of N-substituted derivatives of 3ꢁ. As
expected,4,6 N-alkylation dramatically improved the
inhibitory activity against a- and b-galactosidases. It is
worthy of note that the b-galactose-type valienamines 1
and 18–20 have both been shown to be very strong
inhibitors of b-galactosidase and b-glucosidase, with no
specificity regarding the 4-epimeric structures of the
substrates. This characteristic is in good accordance
with the cases of isofagomine14 and calystegins.15 Very
recently, compound 1 has extensively been studied16 as
an important candidate for generation of novel ther-
apeutic agents for treatment of GM1-gangliosidosis and
b-galactosidosis. Development of such enzyme-inhibi-
tors might advantageously be accelerated by provision
of various N-substituted derivatives, including 19 and
20, readily prepared by use of the versatile precursors
13ꢀ,ꢁ.
The present work describes a convenient synthetic route
for the b-galactose-type valienamine 3ꢁ and some N-
alkyl derivatives thereof, demonstrating that enzyme-
inhibitory activity can be significantly increased by a
suitable N-substitution.
Scheme 2. Reagents and conditions: (a) 1 M NaOMe-MeOH, 1 h, rt;
(MeO)2Me2, DMF, TsOH hydrate, 1 day, rt; Ac2O, pyridine; (b) Br2
(molar equiv), CCl4; rt; (c) NaOAc (1.4 molar equiv), 2 days, rt; (d) for
example; decylamine (6 molar equiv), 2-propanol, 3 days, rt; 80% aq
AcOH, 8 h, 80 ꢀC, 8 h; Dowex 50 Wꢁ2 (H+) resin, 1% NH3-MeOH.

998
S. Ogawa et al. / Bioorg. Med. Chem. 12 (2004) 995–1002
Table 1. Inhibitory activity (IC50, mM) of compounds 1, 3ꢀ,ꢁ, and 18–20 against four glycosidasesa
Compd
IC50 (mM)
a-Galactosidase
(Green coffee beans)
b-Galactosidase
(Bovine liver)
b-Glucosidase
(Almonds)
a-Mannosidase
(Jack beans)
1
3.1
56
12
2.7
1.9
4.4
NT
0.87
NI
NI
3.1
NI
NI
1.2
2.5
0.87
NT
NI
370
190
NI
NI
NI
3ꢀ
3ꢁ
18
19
20
2.3
0.13
0.01
NT
DMJ
150
a Compounds 3ꢀ and 3ꢁ are racemic; DMJ: deoxymannonojirimycin; NI: IC50>0.1 mg/mL; NT: Not tested.
4. Experimental
4.1. General methods
mine (1.2 g, 7.6 mmol) for 1 h at room temperature. The
mixture was then diluted with chloroform (400 mL) and
the solution was washed thoroughly with saturated
aqueous sodium thiosulfate, aqueous sodium hydrogen
carbonate, and water, dried, and evaporated. The resi-
due was chromatographed on a silica gel column (280 g,
6:1 ethyl acetate/hexane) to give about 1:1 mixture of
the dibromides 5ꢀ and 5ꢁ (2.82 g, 90%) as colorless
crystals.
Optical rotations were measured with a JASCO DIP-
370 polarimeter, and [a]D values are given in 10ꢂ1 deg
1
cm2 gꢂ1. H NMR spectra were recorded for solutions
in deuteriochloroform and deuteriomethanol with
internal tetramethylsilane (TMS) as a reference with a
JEOL JNM LAMDA-300 (300 MHz) instrument. 13C
NMR spectra were recorded with the same instrument
(75 MHz). IR spectra were recorded with a JASCO IR-
810 or HITACHI Bio-Rad Digital Lab FTS-65 spec-
trometer. Mass spectra were determined with HITA-
CHI M-8000 ion trap mass spectrometer using
electrospray ionization (ESI). TLC was performed on
silica gel 60 F-254 (E. Merck, Darmstadt). The silica gel
used for a column chromatography was Wakogel C-300
(Wako Junyaku Kogyo Co., Osaka, 200–300 mesh) or
silica gel 60 KO (Katayama Kagaku Kogyo Co., Osaka,
70–230 mesh). Organic solutions were dried over anhy-
drous Na2SO4 and concentrated at >45 ꢀC under
diminished pressure.
The mixture of the products obtained from 4 (320 mg)
was carefully fractionated by chromatography on silica
gel (10:1 EtOAc/hexane) to give pure 5ꢀ (120 mg)
and 5ꢁ (43 mg), together with 5ꢀ,ꢁ (220 mg): 1H
NMR (300 MHz, CDCl3) 5ꢀ: d 6.22 (d, 1H, J=4.6 Hz,
H-5), 5.94 (d, 1H, J=4.1 Hz, H-3), 5.48 (dd, 1H,
J=4.1 and 10.3 Hz, H-2), 5.10 (dd, 1H, J=3.7 and 10.3
Hz, H-1), 5.08 (dd, 1H, J=3.7 and 4.6 Hz, H-6), 3.93 (s,
2H, CH2Br); 5ꢁ: d 6.18 (d, 1H, J=2.7 Hz, H-5), 5.88
(d, 1H, J=3.6 Hz, H-3), 5.69 (dd, 1H, J=7.6 and 10.5
Hz, H-1), 5.10 (dd, 1H, J=3.6 and 10.5 Hz, H-2),
4.61 (dd, 1H, J=2.7 and 7.6 Hz, H-6), 3.91 (s, 2H,
CH2Br).
4.1.1. (1SR,2RS,3SR)-1,2,3-Triacetoxy-4-methylenecyclo-
hex-5-ene (4). A mixture of (1RS,2RS,3RS,4RS,6RS)-
1,2,3-triacetoxy-4-bromo-6-(bromomethyl)cyclohexane8
(1.64 g, 3.81 mmol) and anhydrous sodium acetate (1.25
g, 15.2 mmol) in HMPA (65 mL) was stirred for 2 h at
120 ꢀC. After cooling, the mixture was diluted with ethyl
acetate (210 mL), and the solution was washed thor-
oughly with water, dried, and evaporated. The residue
was chromatographed on a silica gel column (90 g, 1:8
acetone/hexane) to give the conjugated diene 4 (0.73 g,
72%) as a syrup, TLC: Rf 0.45 (1:3 acetone/hexane); 1H
NMR (300 MHz, CDCl3) d 6.25 (br d, 1H, J=10.0 Hz,
H-6), 5.79 (d, 1H, J=2.8 Hz, H-3), 5.70 (br d, 1H,
J=10.0 Hz, H-5), 5.64 (br d, 1H, J=7.6 Hz, H-1), 5.33
and 5.28 (2 s, each 1H, CH2), 5.17 (dd, 1H, J=2.8 and
7.6 Hz, H-2), 2.10 and 2.10 (3 s, each 3H, 3 Ac). This
compound was identified with an authentic sample8 on
comparison with spectral data.
These compounds were identified with authentic sam-
ples8 on comparison with spectral data.
4.1.3. (1RS,2RS,3SR,6SR)- and (1RS,2RS,3SR,6RS)-
1,2,3-Triacetoxy-4-(acetoxymethyl)-6-bromocyclohex-4-
ene [2,3,4,6-tetra-O-acetyl-5a-carba-ꢀ and ꢁ-DL-ara-
bino-hex-5(5a)-enopyranosyl bromide] (6ꢀ and 6ꢁ). A
ca. 1:1 mixture (912 mg, 2.13 mmol) of the dibromides
5ꢀ and 5ꢁ, anhydrous sodium acetate (175 mg, 2.13
mmol) in DMF (14 mL) was stirred for 20 h at room
temperature. The mixture was then diluted with ethyl
acetate (180 mL), and the solution was washed with
saline (3ꢁ60 mL), dried, and evaporated. The residue
was chromatographed on a silica gel column (80 g, 1:3
ethyl acetate/hexane) to give a 1:1 inseparable mixture
(743 mg, 86%) of the bromides 6ꢀ and 6ꢁ as colorless
crystals, TLC: Rf 0.35 (1:2 EtOAc/hexane). This mix-
ture of the compounds was identified with an authentic
sample8 on comparison with spectral data.
4.1.2. (1RS,2RS,3SR,6SR)- and (1RS,2RS,3SR,6RS)-
1,2,3-Triacetoxy-6-bromo-4-(bromomethyl)cyclohex-4-
ene [2,3,4-tri-O-acetyl-6-bromo-6-deoxy-5a-carba-ꢀ and
ꢁ-DL-arabino-hex-5(5a)-enopyranosyl bromide] (5ꢀ and
5ꢁ). To a solution of the diene 4 (1.96 g, 7.34 mmol) in
carbon tetrachloride (40 mL) was added dropwise bro-
Compound 5ꢀ (45 mg) was similarly treated with
sodium acetate (8.6 mg) in DMF (1 mL) to give pro-
ducts, which were shown to be a mixture of 6ꢀ,ꢁ by 1H
NMR spectrum.

S. Ogawa et al. / Bioorg. Med. Chem. 12 (2004) 995–1002
999
4.1.4. (1RS,2RS,3SR,6SR)- and (1RS,2RS,3SR,6RS)-
1,2,3-Triacetoxy-4-(acetoxymethyl)-6-azidocyclohex-4-
ene [2,3,4,6-tetra-O-acetyl-5a-carba-ꢀ and ꢁ-DL-ara-
bino-hex-5(5a)-enopyranosyl azide] (7ꢀ and 7ꢁ). A ca.
1:1 mixture (676 mg, 1.58 mmol) of the bromides 5ꢀ
and 5ꢁ, anhydrous sodium acetate (130 mg, 1.58 mmol)
in DMF (10 mL) was stirred for 15 h at room temper-
ature. When TLC demonstrated almost disappearance
of 5ꢀ and 5ꢁ, sodium azide (205 mg, 3.15 mmol) was
added to the mixture and it was stirred for further 24 h
at room temperature. The mixture was diluted with ethyl
acetate (120 mL), and a solution was washed with saline
(3ꢁ40 mL), dried, and evaporated. The residue was
chromatographed on a silica gel column (50 g, 1:4 ethyl
acetate/hexane) to give about 1:1 inseparable mixture
(456 mg, 78%) of the azides 7ꢀ and 7ꢁ as a colorless
syrup, TLC: Rf 0.51 (1:1 EtOAc/hexane); 1H NMR
(300 MHz, CDCl3) (inter alia) d 5.94 (d, 0.5H, J=4.9
Hz, H-5 of 7ꢀ), 5.88 (d, 0.5H, J=1.2 Hz, H-5 of 7ꢁ),
5.73 (br d, 0.5H, J=2.1 Hz, H-3 of 7ꢀ), 5.70 (d, 0.5H,
J=3.5 Hz, H-3 of 7ꢁ), 5.48 (dd, 0.5H, J=8.1 and 11.0
Hz, H-1 of 7ꢁ). This mixture was identified with an
authentic sample8 on comparison with spectral data.
1H, J=8.9 Hz, H-4), 2.12 and 2.17 (2 s, each 3H, 2 Ac),
1.38 and 1.51 (2 s, each 3H, CMe2); ITMS-ESI (positive
mode): m/z 349 [M+Na]+, 364 [M+K]+.
4.1.6. (1SR,2SR,3SR,6SR)-6-Azido-4-(hydroxymethyl)-
cyclohex-4-ene-1,2,3-triol [5a-carba-ꢀ-DL-arabino-hex-
5(5a)-enopyranosyl azide] (9ꢀ). A solution of 8ꢀ (37
mg, 0.113 mmol) in a mixture of 4 M hydrochloric acid
(0.5 mL) and THF (0.5 mL) for 1 h at reflux temper-
ature. The mixture was evaporated and the residue was
chromatographed on silica gel (1.1 g, 1:10 MeOH/
CHCl3) to give 9ꢀ (18 mg, 80%) as a colorless syrup;
1
TLC: Rf 0.40 (1:4 MeOH/CHCl3); H NMR (300 MHz,
CHCl3): d 5.70 (d, 1H, J=4.2 Hz, H-5), 4.17 (dd, 1H,
J=4.2 and 4.5 Hz, H-6), 4.10 (d, 1H, J=3.9 Hz, H-3),
4.01 (s, 2H, CH2OH), 3.93 (dd, 1H, J=4.5 and 10.0 Hz,
H-1), 3.68 (dd, 1H, J=3.9 and 10.0 Hz, H-2).
4.1.7. (1SR,2RS,3SR,6RS)-6-Azido-4-(hydroxymethyl)-
cyclohex-4-ene-1,2,3-triol [5a-carba-ꢁ-DL-arabino-hex-
5(5a)-enopyranosyl azide] (9ꢁ). Compound 8ꢁ (31 mg,
0.094 mmol) was hydrolyzed as described in the pre-
paration of 9ꢀ to give 9ꢁ (14 mg, 74%) as a colorless
syrup; TLC: Rf 0.40 (1:4 MeOH/CHCl3); 1H NMR
(300 MHz, CHCl3): d 5.57 (d, 1H, J=1.3 Hz, H-5), 4.07
(d, 1H, J=4.2 Hz, H-3), 4.00 (s, 2H, CH2OH), 3.83 (dd,
1H, J=1.3 and 8.3 Hz, H-6), 3.62 (dd, 1H, J=8.3 and
10.7 Hz, H-1), 3.47 (dd, 1H, J=4.2 and 10.7 Hz, H-2).
4.1.5. (1SR,4SR,5SR,6SR)- and (1SR,4RS,5SR,6SR)-5-
Acetoxy-2-(acetoxymethyl)-4-azido-8,8-dimethyl-7,9-di-
oxabicyclo[4.3.0]non-2-ene [2,6-di-O-acetyl-3,4-O-isopro-
pylidene-5a-carba-ꢀ and ꢁ-DL-arabino-hex-5(5a)-enopyr-
anosyl azide] (8ꢀ and 8ꢁ). A solution of the azides 7ꢀ,ꢁ
(113 mg, 0.305 mmol) in methanol (1.1 mL) was treated
with 1 M methanolic sodium methoxide (0.57 mL) for 1
h at room temperature. After neutralization by treat-
ment with Amberlite IR-120 (H+) resin, the solution
was evaporated and the residue was dissolved in dry
DMF (0.87 mL), to which 2,2-dimethoxypropane (0.132
mL, 1.07 mmol) and a catalytic amount of p-toluene-
sulfonic acid monohydrate were added. The mixture
was stirred for 24 h at room temperature, neutralized
with triethyl amine, and then co-evaporated with n-
butanol and toluene to dryness. The residue was treated
with acetic anhydride (0.5 mL) and pyridine (1.0 mL)
overnight at room temperature. After quenched by
addition of methanol (1 mL), the mixture was evapo-
rated to dryness. The residue was chromatographed on
a silica gel column (8.3 g, 1:8 ethyl acetate/hexane) to
give 8ꢀ (44 mg, 44%) and 8ꢁ (42 mg, 42%) as a color-
less syrup.
4.1.8. (1SR,2RS,3SR,6SR)-6-Amino-4-(hydroxymethyl)-
cyclohex-4-ene-1,2,3-triol [5a-carba-ꢀ-DL-arabino-hex-
5(5a)-enopyranosylamine] (3ꢀ). A solution of 9ꢀ (19
mg, 92 mmol) in 50% aqueous THF (2.5 mL) containing
triphenylphosphine (73 mg, 0.28 mmol) was stirred for
24 h at room temperature. The mixture was then passed
through a column of Dowex 50Wꢁ2 (H+) resin (1 mL)
with 1% aqueous ammonia as eluent to give 3ꢀ (14 mg,
86%) as a white powder; TLC: Rf 0.35 (1:1:2H2O/
1
AcOH/n-BuOH); H NMR (300 MHz, D2O): d 5.61 (d,
1H, J=3.9 Hz, H-5), 4.11 (d, 1H, J=3.9 Hz, H-3), 4.00
and 3.95 (ABq, J=15.1 Hz, CH2OH), 3.81 (dd, 1H,
J=9.5 and 9.5 Hz, H-1), 3.72 (dd, 1H, J=3.9 and 9.5
Hz, H-2), 3.47 (br d, 1H, H-6); 13C NMR (75 MHz,
D2O): d 139.16 (C-4), 126.96 (C-5), 69.79 (C-3 or 1),
69.44 (C-1 or 3), 67.40 (C-2), 63.15 (C-7), 49.48 (C-6);
ITMS-ESI (positive mode): m/z 177 [M+H]+, 198
[M+Na]+.
1
For 8ꢀ: TLC: Rf 0.53 (1:2 EtOAc/hexane); H NMR
4.1.9. (1SR,2RS,3SR,6RS)-6-Amino-4-(hydroxymethyl)-
cyclohex-4-ene-1,2,3-triol [5a-carba-ꢁ-DL-arabino-hex-
5(5a)-enopyranosylamine] (3ꢁ). Compound 9ꢁ (20 mg,
0.10 mmol) was treated with triphenylphosphine (53
mg, 0.20 mmol) in 50% aqueous THF (3.5 mL) and a
crude product was purified, as in the preparation of 3ꢀ,
to give 3ꢁ (15 mg, 86%) as a white powder; TLC: Rf
(300 MHz, CDCl3): d 5.88 (d, 1H, J=4.1 Hz, H-3), 5.21
(dd, 1H, J=3.8 and 7.4 Hz, H-2), 4.75 and 4.67 (2 d,
each 1H, J=14.9 Hz, CH2OAc), 4.63 (d, 1H, J=6.2 Hz,
H-1), 4.46 (dd, 1H, J=6.2 and 7.4 Hz, H-6), 4.25 (dd,
1H, J=3.8 and 4.1 Hz, H-4), 2.13 and 2.17 (2 s,
each 3H, 2 Ac), 1.38 and 1.42 (2 s, each 3H, CMe2);
ITMS-ESI (positive mode): m/z 349 [M+Na]+, 365
[M+K]+.
1
0.36 (1:1:2H2O/AcOH/n-BuOH); H NMR (300 MHz,
D2O): d 5.54 (d, 1H, J=1.7 Hz, H-5), 4.10 (d, 1H,
J=3.9 Hz, H-3), 4.01 (s, 2H, CH2OH), 3.57 (dd, 1H,
J=3.9 and 10.3 Hz, H-2), 3.53 (dd, 1H, J=8.3 and 10.3
Hz, H-1); 13C NMR (75 MHz, D2O): d 139.46 (C-4),
127.49 (C-5), 73.34 (C-3 or 1), 72.34 (C-1 or 3), 67.40
(C-2), 62.84 (C-7), 54.41 (C-6); ITMS-ESI (positive
mode): m/z 176.43 [M+H]+, 198 [M+Na]+.
1
For 8ꢁ: TLC: Rf 0.40 (1:2 EtOAc/hexane); H NMR
(300 MHz, CDCl3): d 5.77 (d, 1H, J=1.5 Hz, H-3), 5.15
(dd, 1H, J=8.9 and 8.9 Hz, H-5), 4.66 and 4.74 (2 d,
each 1H, J=13.7 Hz, CH2OAc), 4.59 (d, 1H, J=6.0 Hz,
H-1), 4.22 (dd, 1H, J=6.0 and 8.9 Hz, H-6), 3.97 (br d,

1000
S. Ogawa et al. / Bioorg. Med. Chem. 12 (2004) 995–1002
4.1.10. (1SR,2RS,3SR,6SR)-6-Acetamido-1,2,3-triacet-
oxy-4-(acetoxymethyl)cyclohex-4-ene (10ꢀ). Compound
3ꢀ was treated with acetic anhydride and pyridine in the
usual manner to give the penta-N,O-acetyl derivative
10ꢀ, as a syrup, quantitatively; TLC: Rf 0.42 (1:1 ace-
propylidene-5a-carba-ꢀ and ꢁ-L-arabino-hex-5(5a)-eno-
pyranosyl bromide] (12ꢀ and 12ꢁ). To a solution of 11
(0.657 g, 2.93 mmol) in carbon tetrachloride (6.6 mL)
was added dropwise bromine (0.15 mL, ca. 3 mmol) for
7 min at room temperature. After treatment with satu-
rated aqueous sodium thiosulfate, the mixture was
diluted with chloroform (300 mL), and the solution was
thoroughly washed with saturated sodium hydrogen
carbonate and water, dried, and evaporated. The resi-
due was chromatographed on silica gel (20 g, 1:50
EtOAc/toluene) to give about 1.7:1 inseparable mixture
(824 mg, 76%) of 12ꢀ and 12ꢁ as a colorless syrup.
1
tone/toluene); H NMR (300 MHz, CDCl3): d 5.86 (d,
1H, J=4.4 Hz, H-5), 5.70 (d, 1H, J=2.9 Hz, H-3), 5.57
(d, 1H, J=11.3 Hz, NH), 5.35 (dd, 1H, J=4.2 and 9.6
Hz, H-1), 5.32 (dd, J=2.9 and 9.6 Hz, 1H, H-2), 5.10
(ddd, 1H, J=4.2, 4.4, and 11.3 Hz, H-6), 4.59 and 4.46
(ABq, each 1H, J=13.4 Hz, CH2OAc), 2.09, 2.08, 2.06,
2.05 and 2.02 (5 s, each 3H, 5 Ac); 13C NMR (75 MHz,
CDCl3): d 170.38, 170.25, 170.09, 169.84 (2) (5 CH3CO),
133.00 (C-4), 127.77 (C-5), 67.21 (C-3 or 1), 66.65 (C-1
or 3), 65.36 (C-2), 63.42 (C-7), 45.29 (C-6), 23.26, 21.59,
20.82, 20.69, 20.65 (5 CH3CO); ITMS-ESI (positive
mode): m/z 387 [M+H]+, 408 [M+Na]+.
1
For 12ꢀ: H NMR (300 MHz, CDCl3) (inter alia): d
6.17 (br d, 1H, J=6.4 Hz, H-3), 4.99 (br d, 1H, J=8.3
Hz, H-5), 4.81 (dd, 1H, J=3.7 and 6.4 Hz, H-4), 4.76
(dd, 1H, J=6.8 and 8.3 Hz, H-6), 4.02 and 4.20 (2 d,
each 1H, J=10.5 Hz, CH2Br), 2.19 (s, 3H, Ac), 1.42 and
1.46 (2 s, each 3H, CMe2).
4.1.11. (1SR,2RS,3SR,6RS)-6-Acetamido-1,2,3-triacetoxy-
4-(acetoxymethyl)cyclohex-4-ene (10ꢁ). Compound 3ꢁ
was acetylated in the usual manner to give the penta-
N,O-acetyl derivative 10ꢁ, as a syrup, quantitatively;
TLC: Rf 0.42 (1:1 acetone/toluene); 1H NMR (300 MHz,
CDCl3): d 5.84 (d, 1H, J1,5a=1.4 Hz, H-5), 5.79 (d, 1H,
J=3.9 Hz, H-3), 5.73 (d, 1H, J=8.5 Hz, NH), 5.29 (dd,
1H, J=8.5 and 10.0 Hz, H-1), 5.19 (dd, 1H, J=3.9 and
10.0 Hz, H-2), 4.80 (ddd, 1H, J=1.4, 8.5 and 8.5 Hz, H-
6), 4.55 and 4.46 (ABq, each 1H, J=13.4 Hz, CH2OAc),
2.11, 2.05 and 1.98 (3 s, each 3H, 3 Ac), 2.08 (br s, 6H, 2
Ac); 13C NMR (75 MHz, CDCl3): d 171.46, 170.37,
170.06, 169.97, 169.61 (5 CH3CO), 131.08 (C-4), 130.49
(C-5), 69.39 (C-3 or 1), 68.92 (C-1 or 3), 65.76 (C-2),
63.64 (C-7), 51.07 (C-6), 23.23, 20.83, 20.77, 20.74,
20.54 (5 CH3CO); ITMS-ESI (positive mode): m/z 387
[M+H]+, 408 [M+Na]+.
1
For 12ꢁ: H NMR (300 MHz, CDCl3) (inter alia): d
6.17 (br s, 1H, H-3), 5.37 (dd, 1H, J=8.3 and 8.3 Hz, H-
5), 4.87 (d, 1H, J=5.5 Hz, H-1), 4.49 (br d, 1H, H-4),
4.20 (s, 2H, CH2Br), 2.15 (s, 3H, Ac), 1.41 and 1.51 (2 s,
each 3H, CMe2).
4.1.14. (1S,4S,5R,6S)- and (1S,4R,5R,6S)-5-Acetoxy-2-
(acetoxymethyl)-4-bromo-8,8-dimethyl-7,9-dioxabicyclo-
[4.3.0]non-2-ene [2,6-di-O-acetyl-3,4-O-isopropylidene-5a-
carba-ꢀ and ꢁ-L-arabino-hex-5(5a)-enopyranosyl bro-
mide] (13ꢀ and 13ꢁ). A mixture (27 mg, 70 mmol) of
12ꢀ,ꢁ and sodium acetate (6.3 mg, 0.10 mmol) in DMF
(1 mL) was stirred for 2 days at room temperature. The
mixture was then diluted with ethyl acetate (12 mL), the
solution was thoroughly washed with saline and water,
dried, and evaporated. The residual product (27 mg)
was chromatographed on silica gel (4 g, 1:8 EtOAc/
hexane) to give 13ꢀ (12 mg, 48%) and 13ꢁ (6 mg, 23%)
as a colorless syrup.
4.1.12. (1S,2S,6S)-2-Acetoxy-8,8-dimethyl-5-methylene-
7,9-dioxabicyclo[4.3.0]non-3-ene (11). A solution of the
diene8,11 D–4 (1.36 g, 5.06 mmol) in methanol (21 mL)
was treated with sodium methoxide (55 mg, 1.0 mmol)
for 2 h at room temperature. After neutralization with
Amberlite IR-120 (H+) resin, the mixture was evapo-
rated. The residue was treated with 2,2-dimethoxy-
propane (2.0 mL, 1.6 mmol) and p-toluenesulfonic acid
monohydrate (0.21 g, 1.1 mmol) for 23 h at room temp-
erature. After neutralization with triethylamine, the mix-
ture was evaporated to dryness and the residual product
was acetylated with acetic anhydride (5.5 mL) and pyridine
(11 mL) overnight at room temperature in the usual
manner. The product was chromatographed on a silica
gel column (30 g, 1:11 EtOAc/hexane) as eluent to give
11 (807 mg, 71%) as a colorless syrup; TLC: Rf 0.52 (1:1
For 13ꢀ: TLC: Rf 0.36 (1:2 ethyl acetate/hexane); [a]D20
ꢀ
1
+277 (c 1.13, CHCl3); H NMR (300 MHz, CDCl3): d
6.09 (d, 1H, J=7.7 Hz, H-3), 4.83 (dd, 1H, J=3.9 and
7.7 Hz, H-4), 4.79 (dd, 1H, J=3.9 and 8.5 Hz, H-5),
4.71 (d, 1H, J=6.5 Hz, H-1), 4.67 and 4.74 (ABq, each
1H, J=14.3 Hz, CH2OAc), 4.55 (dd, 1H, J=6.5 and 8.5
Hz, H-6), 2.13 and 2.19 (2 s, each 3H, 2 Ac), 1.40 and
1.46 (2 s, each 3H, CMe2); ITMS-ESI (positive mode):
m/z 283 [M–79Br]+, 305 [M+Na–79Br]+, 385
[M+Na]+.
For 13ꢁ: TLC: Rf 0.31 (1:2 EtOAc/hexane); [a]2D1 +33ꢀ
(c 0.78, CHCl3); 1H NMR (300 MHz, CDCl3): d 6.04 (br
s, 1H, H-3), 5.39 (dd, 1H, J=8.3 and 8.3 Hz, H-5), 4.67
and 4.75 (ABq, each 1H, J=13.6 Hz, CH2OAc), 4.58
(d, 1H, J=5.9 Hz, H-1), 4.50 (br d, 1H, J=8.3 Hz, H-
4), 4.17 (dd, 1H, J=5.9 and 8.3 Hz, H-6), 2.12 and 2.15
(2 s, each 3H, 2 Ac), 1.38 and 1.52 (2 s, each 3H, CMe2);
ITMS-ESI (negative mode): m/z 361 [MꢂH]ꢂ.
EtOAc/hexane), [a]2D3 +149ꢀ (c 0.89, CHCl3); H NMR
1
(300 MHz, CDCl3): d 6.30 (br d, 1H, J=10.3 Hz, H-4),
5.67 (br d, 1H, H-3), 5.43 (d, 1H, J=5.4 Hz, H-2), 5.42
and 5.44 (2 s, each 1H, CH2), 4.71 (d, 1H, J=5.5 Hz, H-
6), 4.21 (dd, 1H, J=5.4 and 5.5 Hz, H-1), 2.11 (s, 3H,
Ac), 1.44 and 1.49 (2 s, each 3H, CMe2); ITMS-ESI
(positive mode): m/z 247 [M+Na]+, 263 [M+K]+.
4.1.13. (1S,4S,5R,6S)- and (1S,4R,5R,6S)-5-acetoxy-4-
bromo-2-(bromomethyl)-8,8-dimethyl-7,9-dioxabicyclo-
[4.3.0]non-2-ene [2-O-acetyl-6-bromo-6-deoxy-3,4-O-iso-
4.1.15. (1S,4R,5R,6S)-4-Hexylamino-5-hydroxy-2-(hydro-
xymethyl)-8,8-dimethyl-7,9-dioxabicyclo[4.3.0]non-2-ene
[N-hexyl-3,4-O-isopropylidene-5a-carba-ꢀ-L-arabino-hex-

S. Ogawa et al. / Bioorg. Med. Chem. 12 (2004) 995–1002
1001
5(5a)-enopyranosylamine] (14). A mixture of 13ꢀ (39
mg, 0.11 mmol), n-hexylamine (143 mL, 1.1 mmol), and
2-propanol (0.4 mL) was stirred for a week at room
temperature, and then evaporated to dryness. The resi-
due was chromatographed on a silica gel column (4 g,
1:40 MeOH/CHCl3) to give 14 (21 mg, 64%) as a white
powder, TLC: Rf 0.46 (1:4 MeOH/CHCl3); [a]2D0 ꢂ27 ꢀ (c
J=4.2 Hz, H-3), 4.12 (br s, 2H, CH2OH), 3.70 (dd, 1H,
J=8.1 and 10.3 Hz, H-1), 3.43 (dd, 1H, J=4.2 and 10.3
Hz, H-2), 3.12 (d, 1H, J=8.1 Hz, H-6), 2.56 and 2.75 (2
m, each 1H, NCH2), 1.52 (m, 2H, NHCH2CH2), 1.31
[m, 10H, CH2(CH2)5CH3], 0.89 (t, 3H, J=6.7 Hz,
CH2CH3); ITMS-ESI (positive mode): m/z 288
[M+H]+.
1
0.4, CHCl3); H NMR (300 MHz, CDCl3): d 5.88 (br s,
1H, H-5), 4.63 (d 1H, J=6.8 Hz, H-3), 4.18 and 4.26
(ABq, each 1H, J=11.7 Hz, CH2OH), 4.13 (dd, 1H,
J=6.8 and 8.5 Hz, H-2), 3.44 (dd, 1H, J=8.5 and 9.2
Hz, H-1), 3.04 (d, 1H, J=9.2 Hz, H-6), 2.81 and 2.43 (2
dt, each 1H, J=7.3 and 11.2 Hz, NHCH2), 2.58 (br s,
2H, OH), 1.49 and 1.40 (2 s, each 3H, CMe2), 1.54–1.26
[m, 8H, NHCH2(CH2)4], 0.89 (t, 3H, J=6.7 Hz,
CH2CH3).
4.1.19. (1S,4R,5R,6S)-4-Decylamino-5-hydroxy-2-(hydro-
xymethyl)-8,8-dimethyl-7,9-dioxabicyclo[4.3.0]non-2-ene
[N-decyl-3,4-O-isopropylidene-5a-carba-ꢀ-L-arabino-hex-
5(5a)-enopyranosylamine] (16). A mixture of 13ꢀ (36
mg, 99 mmol), n-decylamine (120 mL, 0.59 mmol) was
stirred for 3 days at room temperature. The mixture was
processed as in the preparation of 14 to give 16 (14 mg,
40%) as a white powder, TLC: Rf 0.44 (1:5 MeOH/
CHCl3); [a]2D0 ꢂ19ꢀ (c 0.43, CHCl3); 1H NMR (300 MHz,
CDCl3): d 5.88 (br s, 1H, H-5), 4.63 (d, 1H, J=6.6 Hz,
H-3), 4.17 and 4.27 (ABq, each 1H, J=13.7 Hz,
CH2OH), 4.14 (dd, 1H, J=6.6 and 8.5 Hz, H-2), 3.44
(dd, 1H, J=8.5 and 9.0 Hz, H-1), 3.06 (d, 1H, J=9.0
Hz, H-6), 2.81 and 2.55 (2 dt, each 1H, J=7.2 and 11.2
Hz, NHCH2), 2.66 (br s, 2H, OH), 1.40 and 1.49 (2 s,
each 3H, CMe2), 1.26–1.54 [m, 16H, (CH2)8CH3], 0.88
(t, 3H, J=6.6 Hz, CH2CH3).
4.1.16. (1S,2R,3S,6R)-6-Hexylamino-4-(hydroxymethyl)-
cyclohex-4-ene-1,2,3-triol [N-hexyl-5a-carba-ꢁ-L-arabino-
hex-5(5a)-enopyranosylamine] (18). A mixture of 14 (7.9
mg, 26 mmol) and 80% aqueous acetic acid (2 mL) was
stirred for 30 h at 80 ꢀC. The product was purified by a
column of Dowex 50 Wꢁ2 (H+) resin (0.7 g) with
methanolic 1% ammonia as eluent to give 18 (7.5 mg,
ꢃ100%) as a white powder, [a]2D0 ꢂ1.9ꢀ (c 0.34,
1
MeOH); H NMR (300 MHz, CD3OD): d 5.71 (br s,
1H, H-5), 4.15 (d, 1H, J=4.2 Hz, H-3), 4.12 (br s, 2H,
CH2OH), 3.70 (dd, 1H, J=8.1 and 10.3 Hz, H-1), 3.43
(dd, 1H, J=4.2 and 10.3 Hz, H-2), 3.10 (dd, 1H, J=2.0
and 8.1 Hz, H-6), 2.56 and 2.74 (2 dt, each 1H, J=7.3
and 11.4 Hz, NHCH2), 1.52 (m, 2H, NHCH2CH2), 1.32
[m, 6H, CH2(CH2)3CH3], 0.91 (t, 3H, J=6.7 Hz,
CH2CH3); ITMS-ESI (positive mode): m/z 260
[M+H]+.
4.1.20. (1S,2R,3S,6R)-6-Decylamino-4-(hydroxymethyl)-
cyclohex-4-ene-1,2,3-triol [N-decyl-5a-carba-ꢀ-L-arabino-
hex-5(5a)-enopyranosylamine] (19). Compound 16 (10.4
mg, 29 mmol) was deprotected as in the preparation of
14 to give 19 (6.7 mg, 73%) as a white powder, TLC: Rf
0.48 (1:3:6 AcOH /MeOH/CHCl3); [a]2D1 +12ꢀ (c 0.12,
1
MeOH); H NMR (300 MHz, CD3OD): d 5.62 (d, 1H,
J=2.0 Hz, H-5), 4.06 (d, 1H, J=4.2 Hz, H-3), 4.03 (br
s, 2H, CH2OH), 3.60 (dd, 1H, J=7.6 and 10.3 Hz, H-1),
3.34 (dd, 1H, J=4.2 and 10.3 Hz, H-2), 3.01 (d, 1H,
J=8.1 Hz, H-6), 2.46 and 2.65 (2 dt, each 1H, J=7.4
and 11.3 Hz, NHCH2), 1.43 (m, 2H, NHCH2CH2), 1.20
[m, 14H, CH2(CH2)7CH3], 0.80 (t, 3H, J=6.7 Hz,
CH2CH3); ITMS-ESI (positive mode): m/z 316 [M+H]+.
4.1.17. (1S,4R,5R,6S)-5-Hydroxy-2-(hydroxymethyl)-8,8-
dimethyl-4-octylamino-7,9-dioxabicyclo[4.3.0]non-2-ene
[N-octyl-3,4-O-isopropylidene-5a-carba-ꢀ-L-arabino-hex-
5(5a)-enopyranosylamine] (15). A mixture of 13ꢀ (38
mg, 0.105 mmol), n-octylamine (174 mL, 1.1 mmol), and
2-propanol (0.4 mL) was stirred for a week at room
temperature. The reaction mixture was processed as in
the preparation of 14 to give, after chromatography on
silica gel, 15 (24 mg, 68%) as a white powder, TLC: Rf
0.46 (1:4 MeOH/CHCl3); [a]2D0 ꢂ20 ꢀ (c 0.24, CHCl3); 1H
NMR (300 MHz, CDCl3): d 5.88 (br s, 1H, H-5), 4.64
(d, 1H, J=6.8 Hz, H-3), 4.18 and 4.27 (ABq, each 1H,
J=13.7 Hz, CH2OH), 4.14 (dd, 1H, J=6.8 and 8.7 Hz,
H-2), 3.43 (dd, 1H, J=8.7 and 9.0 Hz, H-1), 3.04 (d,
1H, J=9.0 Hz, H-6), 2.81 and 2.55 (dt, each 1H, J=7.3
and 11.3 Hz, H-6), 2.36 (br s, 2H, OH), 1.40 and 1.50 (2
s, each 3H, CMe2), 1.27–1.53 [m, 12H, NHCH2(CH2)6],
0.88 (t, 3H, J=6.5 Hz, CH2CH3).
4.1.21. (1S,4R,5R,6S)-4-Dodeylamino-5-hydroxy-2-(hy-
droxymethyl)-8,8-dimethyl-7,9-dioxabicyclo[4.3.0]non-2-
ene [N-dodeyl-3,4-O-isopropylidene-5a-carba-ꢀ-L-arabino-
hex-5(5a)-enopyranosylamine] (17). A mixture of 13ꢀ
(40 mg, 0.11 mmol), n-dodecylamine (203 mg, 1.1
mmol), and 2-propanol (0.4 mL) was stirred for a week
at room temperature. The mixture was processed as in
the preparation of 14 to give, after chromatography on
silica gel to give 17 (14 mg, 40%) as a white powder,
ꢀ
TLC: Rf 0.39 (1:5 MeOH/CHCl3); [a]2D0 ꢂ11 (c 0.35,
1
CHCl3); H NMR (300 MHz, CDCl3): d 5.90 (br s, 1H,
H-5), 4.63 (d, 1H, J=6.8 Hz, H-3), 4.18 and 4.27 (ABq,
each 1H, J=13.7 Hz, CH2OH), 4.14 (dd, 1H, J=6.8
and 8.7 Hz, H-2), 3.45 (dd, 1H, J=8.7 and 9.1 Hz, H-1),
3.07 (d, 1H, J=9.1 Hz, H-6), 2.56 and 2.82 (2 dt, each
1H, J=7.2 and 11.3 Hz, NHCH2), 2.69 (br s, 2H, OH),
1.40 and 1.50 (2 s, each 3H, CMe2), 1.26–1.56 [m, 20H,
(CH2)10CH3], 0.88 (t, 3H, J=6.6 Hz, CH2CH3).
4.1.18. (1S,2R,3S,6R)-4-(Hydroxymethyl)-6-octylamino-
cyclohex-4-ene-1,2,3-triol [N-octyl-5a-carba-ꢀ-L-arabino-
hex-5(5a)-enopyranosylamine] (1). Compound 15 (4.7
mg, 14 mmol) was deprotected as in the preparation of
14 to give, after passage through a column of Dowex 50
Wꢁ2 with 1% methanolic ammonia, 1 (2.3 mg, 56%) as
a white powder, TLC: Rf 0.38 (1:3:6 AcOH/MeOH/
CHCl3); [a]2D0 +6.3ꢀ (c 0.5, MeOH); 1H NMR
(300 MHz, CD3OD): d 5.71 (br s, 1H, H-5), 4.15 (d, 1H,
4.1.22. (1S,2R,3S,6R)-6-Dodecylamino-4-(hydroxymethyl)-
cyclohex-4-ene-1,2,3-triol [N-dodecyl-5a-carba-ꢀ-L-ara-
bino-hex-5(5a)-enopyranosylamine] (20). Compound 17

1002
S. Ogawa et al. / Bioorg. Med. Chem. 12 (2004) 995–1002
(7.0 mg, 18 mmol) was deprotected as in the preparation
of 18 to give 20 (5.4 mg, 87%) as a white powder, TLC:
Rf 0.41 (1:2:6 AcOH/MeOH/CHCl3); [a]2D1 +0.7ꢀ (c
4. Ogawa, S.; Ashiura, M.; Uchida, C.; Watanabe, S.;
Yamazaki, C.; Yamagishi, K.; Inokuchi, J. Bioorg. Med.
Chem. Lett. 1996, 6, 929.
5. Ogawa, S.; Kobayashi, Y.; Kabayama, K.; Jimbo, M.;
Inokuchi, J. Bioorg. Med. Chem. 1998, 6, 1955.
6. Ogawa, S.; Watanabe, M.; Maruyama, A.; Hisamatsu, S.
Bioorg. Med. Chem. Lett. 2002, 12, 749.
7. Ogawa, S.; Sekura, R.; Maruyama, A.; Yuasa, H.;
Hashimoto, H. Eur. J. Org. Chem. 2000, 2089.
8. Ogawa, S.; Hattori, H.; Toyokuni, T.; Suami, T. Bull.
Chem. Soc. Jpn. 1983, 56, 2077.
9. When the mixture of 6ꢀ,ꢁ, isolated is treated similarly
with excess sodium azide, the proportion of the b-azide
7ꢁ, formed is likely to increase about 1.5 to 2.0 fold.
10. Toyokuni, T.; Ogawa, S.; Suami, T. Bull. Chem. Soc. Jpn.
1983, 56, 1161.
11. Following the established route8 combined with the pre-
sent improved processing, optically active D-4, [a]2D1 +209ꢀ
(c 0.92, CHCl3), was prepared from (1S,2R,3S,4S,6R)-
1,2-diacetoxy-3,4-dibromo-6-(bromomethyl)cyclohexane:
Ogawa, S.; Uematsu, Y.; Yoshida, S.; Sasaki, N.; Suami,
T. J. Carbohydr. Chem. 1987, 6, 471.
12. The protected N-alkylamines were here demonstrated to
be easily isolated and purified, allowing us to subject them
to further chemical modification. Practically, one-pot
processing of treatment of 13ꢀ,ꢁ with alkyl amines, fol-
lowed by hydrolysis, can improve isolated yields of the
corresponding free amines. The reaction conditions have
not yet been optimized.
13. All biological assays were carried out in a standard man-
ner by Dr. Akihiro Tomoda (Hokko Chemical Industry,
Co. Ltd.).
1
0.27, MeOH); H NMR (300 MHz, CD3OD): d 5.71 (br
s, 1H, H-5), 4.15 (d, 1H, J=4.1 Hz, H-3), 4.12 (br s, 2H,
CH2OH), 3.69 (dd, 1H, J=8.1 and 9.6 Hz, H-1), 3.43
(dd, 1H, J=4.1 and 9.6 Hz, H-2), 3.10 (d, 1H, J=8.1
Hz, H-6), 2.56 and 2.74 (2 dt, each 1H, J=7.1 and 11.5
Hz, NHCH2), 1.52 (m, 2H, NHCH2CH2), 1.28 [m, 18H,
CH2(CH2)9CH3], 0.89 (t, 3H, J=6.6 Hz, CH2CH3);
ITMS-ESI (positive mode): m/z 344 [M+H]+.
4.2. Biological assay
Compounds were assayed13 for enzyme inhibitory
activity (IC50) against six glycohydrolases: a-glucosidase
(Baker’s yeast), b-glucosidase (almonds), a-galactosi-
dase (green coffee beans), b-galactosidase (bovine liver),
a-mannosidase (Jack beans), and a-fucosidase (bovine
kidney). All compounds did not exhibit any inhibitory
activity toward a-glucosidase and a-fucosidase.
Acknowledgements
The authors would like to thank Drs. Atsushi Takaha-
shi and Akihiro Tomoda (Hokko Chemical Industry
Co. Ltd., Atsugi) for biological assays, Profs. Naoki
Asano (Hokuriku University, Kanazawa) and Yoshi-
yuki Suzuki (International University of Health and
Welfare, Otawara) for helpful discussion, Misses. Yoriko
Ooki and Midori Mori (Tokyo Metropolitan University,
Hachioji) for measurement of mass spectra, and Ms.
Miki Kanto for assistance in preparing this manuscript.
14. (a) Jespersen, T. M.; Dong, W.; Sierks, M. R.;
Skrydstrup, T.; Lundt, I.; Bols, M. Angew. Chem., Int. Ed.
Engl. 1994, 33, 1778. (b) Ichikawa, Y.; Igarashi, Y.; Ichi-
kawa, M.; Suhara, Y. J. Am. Chem. Soc. 1998, 120, 3007.
15. Asano, N.; Kato, A.; Oseki, K.; Kizu, H.; Matsui, K. Eur.
J. Biochem. 1995, 229, 369.
16. (a) Suzuki, Y.; Nanba, E.; Ohno, K.; Matsuda, J.; Ogawa,
S. Thirty-first National Meeting of the Child Neurology
Society, Washington, DC, 2002, 10.9-12. (b) Matsuda, J.;
Suzuki, O.; Oshima, A.; Yamamoto, Y.; Noguchi, A.;
Takimoto, K.; Itoh, M.; Matsuzaki, Y.; Yasuda, Y.;
Ogawa, S.; Sakata, Y.; Nanba, E.; Higaki, K.; Ogawa, Y.;
Tominaga, L.; Ohno, K.; Iwasaki, H.; Watanabe, H.;
Brandy, R. O.; Suzuki, Y. Proc. Natl. Acad. Sci. U.S.A.,
2003 in press.
References and notes
1. Fan, J.-Q.; Ishii, S.; Asano, N.; Suzuki, Y. Nature Med.
1999, 5, 112.
2. Fan, J.-Q.; Asano, N.; Suzuki, Y.; Ishii, S. Glycoconjugate
1999, J16, S156.
3. Ogawa, S.; Matsunaga, Y. K.; Suzuki, Y. Bioorg. Med.
Chem. 2002, 10, 1967.