Parasite glycoconjugates. Part 11: Preparation of phosphodisaccharide synthetic probes, substrate analogues for the elongating α-D-mannopyranosylphosphate transferase in the Leishmania

Article abstract of DOI:10.1039/b004653l

The preparation of phosphodisaccharide synthetic probes was presented. The Koenings-Knorr and trichloroacetimidate methods for the glycosylation reactions, S_n2 nucleophilic displacement of a triflic ester for epimerization and the glycosyl hydr

Full text of DOI:10.1039/b004653l

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Parasite glycoconjugates. Part 11.1 Preparation of
phosphodisaccharide synthetic probes, substrate analogues for the
elongating ꢀ-D-mannopyranosylphosphate transferase in the
Leishmania
1
Andrew J. Ross,a Irina A. Ivanova,a Michael A. J. Fergusonb and Andrei V. Nikolaev*a
a Department of Chemistry, University of Dundee, Dundee, UK DD1 4HN
b Department of Biochemistry, University of Dundee, Dundee, UK DD1 4HN
Received (in Cambridge, UK) 12th June 2000, Accepted 10th November 2000
First published as an Advance Article on the web 11th December 2000
A set of phosphodisaccharides, substrate analogues, which will be used to study acceptor–substrate specificity
of the Leishmania biosynthetic enzymes, are synthesized using the Koenigs–Knorr and trichloroacetimidate methods
for the glycosylation reactions, SN2 nucleophilic displacement of a triflic ester for epimerization, and the glycosyl
hydrogenphosphonate method for phosphorylation.
strate 1 at C-2 and C-3, respectively, of the -mannopyranose
moiety. Compounds 8 and 9 are substrate analogues deoxy-
genated at positions C-6 and C-6Ј, respectively. In this context,
the preparation of the analogue 10, which is an epimer of com-
pound 9 at C-1Ј and could be (as well as the analogue 9 itself)
a potential inhibitor of the enzyme, is also described. The
information obtained from testing the acceptor activity of the
Introduction
Throughout the tropics and subtropics Leishmania parasites
cause a variety of diseases ranging from self-limiting skin
lesions to the often fatal visceral leishmaniasis. The surface
lipophosphoglycan (LPG) produced by the infectious pro-
mastigote stage of all species of the Leishmania contains a
polymeric section consisting of (1→6)-linked β--galactosyl-
substrate analogues 2–10 will be used to predict which sugar
(1→4)-α--mannosyl phosphate repeating units. The import-
hydroxy groups of compound 1 are involved in enzyme–
ance of the LPG for parasite infectivity and survival2 makes the
substrate recognition events and to design potential enzyme
enzymes responsible for the biosynthesis of this glycoconjugate
inhibitors.
of great interest. Phospho-oligosaccharide fragments of the
LPG of L. donovani, L. mexicana and L. major were synth-
Results and discussion
esized3–6 in our laboratory and tested as acceptor substrates
(in vitro) for the Leishmania α--mannopyranosylphosphate
transferase (MPT) responsible for the transfer of α--Manp
phosphate from GDP-Man to the growing phosphogly-
can chain. It was shown7 that the phosphodisaccharide 14,8
(representing one repeating unit of the phosphoglycan) is the
minimal structure exhibiting acceptor substrate activity for the
MPT.
The synthetic schemes for the preparation of the phospho-
disaccharides 6–10 consist of a few general steps (Scheme 1): 1)
synthesis of fully protected disaccharide derivatives A; 2)
anomeric de-O-protection ( → B); 3) H-phosphonylation at
position O-1 ( → C); 4) coupling of the H-phosphonates C
with dec-9-en-1–ol (using the glycosyl H-phosphonate
method)9 to furnish the protected glycosyl phosphodiesters D;
5) total de-O-protection.
The octa-O-acetyl-α,β-lactose 11 (α:β = 7:1; which is a pre-
cursor of the phosphodisaccharide 6; Scheme 2) was prepared
by conventional acetylation of α-lactose and then converted
to the hemiacetal 12 (83%; α:β = 4:1) by anomeric de-O-acyl-
ation3–6,8–10 with dimethylamine in CH3CN–THF. H-Phosphon-
ylation3–6,8–10 of compound 12 with triimidazolylphosphine
(prepared in situ from PCl3, imidazole and Et3N) followed
by mild hydrolysis produced a mixture of α- and β-linked
In Part 98 of this series, we disclosed our interest in the
design and synthesis of various structural analogues of com-
pound 1 to test the fine acceptor substrate specificity of the
MPT and to gain more information about enzyme–substrate
recognition. Thus, phosphodisaccharides 2–5, which are
epimers of the substrate 1 at C-1Ј, C-2Ј, C-3Ј or C-4Ј, respect-
ively, have been synthesized.
We now report the chemical synthesis of the disaccharide
phosphates 6–10. Compounds 6 and 7 are epimers of the sub-
Scheme 1 R = Ac, or Bz; RЈ = Ac, or Bz, or Bn.
72
J. Chem. Soc., Perkin Trans. 1, 2001, 72–81
This journal is © The Royal Society of Chemistry 2001
DOI: 10.1039/b004653l

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1
H-phosphonates 13 (α:β = 4:1, as evinced from H and 31P
tetrabutylammonium benzoate (Bu4NOBz) in toluene (60 ЊC)
NMR spectra, see Experimental section), which were not
separable by flash-column chromatography. This mixture was
converted to the pure α-(H-phosphonate) 14 (48% based on the
hemiacetal 12) by treatment with H3PO3 in acetonitrile. This
procedure was developed first for the preparation10 of pure
2,3,4,6-tetra-O-benzoyl-α--galactopyranosyl H-phosphonate
and utilizes the higher reactivity of the β-linked glycosyl
H-phosphonate, converting it to either the α-linked isomer (as
a result of SN2-attack), or easily separable hemiacetal deriv-
ative (product of acid-catalyzed cleavage of the H-phosphonate
group).
Synthesis of the protected benzyl β--galactopyranosyl-
(1→4)-α--altropyranoside 22 (which is a precursor of the
phosphodisaccharide 7; Scheme 3) was performed from benzyl
2,3,6-tri-O-benzoyl-α--altropyranoside 20 and acetobromo-
galactose 21. The altropyranoside 20 in turn was prepared
starting from benzyl α--mannopyranoside, which was
converted first to the 2-O-benzoate 17 (65%) by 4,6-O-isopro-
pylidenation11 with 2-methoxypropene ( → 16) followed by
selective benzoylation12 with benzoyl cyanide in the presence of
Et3N. Successive reaction with triflic anhydride in CH2Cl2 in the
presence of pyridine led to the triflate 18, which reacted with
to give the altroside 19 (73%). The -altro-configuration of the
derivative 19 was confirmed by the characteristic values of
1
J2,3 = J3,4 = 3.0 Hz in H NMR spectrum. Further, compound
19 was converted to the glycosyl acceptor 20 (67%) by acid
hydrolysis followed by selective 6-O-benzoylation with benzoyl
cyanide.
Glycosylation of the acceptor 20 with the bromide 21 in the
presence of silver triflate (AgOTf), silver carbonate and
molecular sieves 4 Å in dichloromethane provided the di-
saccharide 22 in 52% yield. Hydrogenolysis of compound 22
over Pd(OH)2/C afforded a mixture of α- and β-hemiacetals
24 in the ratio α:β = 0.8:1 (confirmed by 1H NMR data,
see Experimental section). Probably, the mutarotation was
facilitated because of unfavourable 1,3-synaxial interaction
between 1-OH and 3-benzoate in the α-hemiacetal. The ano-
meric mixture 24 was converted to the pure α-(H-phosphonate)
23 using the same procedure as described for the H-phos-
phonate 14: i.e., the reaction with triimidazolylphosphine and
mild hydrolysis ( → 25) followed by treatment with H3PO3 in
CH3CN. This produced the H-phosphonate 23 (35% based on
the disaccharide 22) along with the recovered hemiacetal 24
(49%).
J. Chem. Soc., Perkin Trans. 1, 2001, 72–81
73

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Scheme 3 Reagents: i, BzCN, Et3N, MeCN; ii, Tf2O, CH2Cl2–pyridine;
iii, Bu4NOBz, toluene; iv, 80% AcOH; v, AgOTf, Ag2CO3, MS 4 Å,
CH2Cl2; vi, H2, Pd(OH)2/C, THF; vii, (a) triimidazolylphosphine,
MeCN; (b) Et3NHHCO3, water (pH 7); viii, H3PO3, MeCN; ix, (a) dec-
9-en-1-ol, trimethylacetyl chloride, pyridine; (b) I2, pyridine–water; x,
NaOMe, MeOH.
In contrast to the anomeric de-O-acylation of the per-
acetylated lactose 11 (see above), similar reaction of the disac-
charide heptaacetate 29 and heptabenzoates 37 and 40 with
dimethylamine in CH3CN–THF afforded the pure α-hemiacetal
derivatives 30, 38 and 42 (66–90%), respectively. Compounds
30, 38 and 42 were then treated with triimidazolylphosphine
followed by mild hydrolysis to produce the α-linked glycosyl
H-phosphonates 31, 39 and 43, respectively, in 70–97% yield.
The structures of all the prepared disaccharide H-phos-
phonates were confirmed by NMR and mass spectrometric
data (see Experimental section). For example, signals character-
istic of the H-phosphonate group [δP 0.77; δH 5.67 (dd, J1,2 3.4,
Scheme 2 Reagents: i, Me2NH, MeCN–THF; ii, (a) triimidazolyl-
phosphine, MeCN; (b) Et3NHHCO3, water (pH 7); iii, H3PO3, MeCN;
iv, (a) dec-9-en-1-ol, trimethylacetyl chloride, pyridine; (b) I2, pyridine–
water; v, NaOMe, MeOH.
The hepta-O-acetyl-β--galactopyranosyl-(1→4)-α--rham-
nopyranose 29 (which is a precursor of the phosphodisacchar-
ide 8; Scheme 4) was synthesized using acetobromogalactose
21 and methyl 2,3-O-isopropylidene-α--rhamnopyranoside13
27 as starting materials. Their coupling in the presence of
Hg(CN)2–HgBr2 in acetonitrile–toluene gave the disaccharide
28 (74%), which was converted to the crystalline hepta-
acetate 29 in 69% yield by acid hydrolysis followed by
acetolysis/acetylation14 with 1.32% (v/v) H2SO4 in acetic
anhydride.
The hepta-O-benzoyl-β--fucopyranosyl-(1→4)-α--manno-
pyranose 37 (which is a precursor of the phosphodisaccharide
9; Scheme 5) was prepared in 62% yield by the glycosylation
of the -mannose tetrabenzoate3 36 with the α--fucosyl
trichloroacetimidate 35 in the presence of trimethylsilyl (TMS)
triflate. A small proportion of the isomeric α-linked disacchar-
ide 40 (13%; a precursor of the phosphodisaccharide 10;
Scheme 6) was also isolated from the reaction mixture. The
trichloroacetimidate 35 in turn was synthesized from -fucose
by consecutive standard benzoylation ( → 33), anomeric
deprotection with Me2NH ( → 34; 61%) and the reaction
(93% yield) with trichloroacetonitrile in the presence of
1,8–diazabicyclo[5.4.0]undec-7-ene (DBU).15
1
J1,P 8.8, 1-H), 6.89 (d, JH,P 637.8, HP)] were present in the 31P
and 1H NMR spectra of the derivative 14. The α-configuration
of the -glucopyranosyl residue followed from the character-
istic value of J1,2. The main signal in the (electrospray) ES(Ϫ)
mass spectrum corresponded to the pseudomolecular ion (m/z
698.9, [M Ϫ Et3N Ϫ H]Ϫ) for the compound. The structures 23,
31, 39 and 43 were established in similar manner apart from
that the α-configuration of the -Altp (in compound 23),
-Rhap (in compound 31) and -Manp (in compounds 39
and 43) residues followed from the characteristic positions of
1
the 3- and 5-H resonances in H NMR spectra. The chemical
shifts of these signals were close to those of 3- and 5-H of the
disaccharide derivatives 22 (containing a benzyl 2,3,6-tri-O-
benzoyl-α--altropyranoside moiety), 29 (containing
a
1,2,3-tri-O-acetyl-α--rhamnopyranose moiety) and 37 and 40
(both containing 1,2,3,6-tetra-O-benzoyl-α--mannopyranose
moieties), respectively.
The glycosyl H-phosphonates 14, 23, 31, 39 and 43 were
converted to the protected phosphodiesters 15, 26, 32, 41 and
44 (75-96% yield), respectively, by their condensation with dec-
9-en-1-ol in pyridine in the presence of trimethylacetyl chloride
followed by oxidation of the resulting H-phosphonic diesters
with iodine in aq. pyridine. The deprotected phosphodi-
The β-configuration of newly formed glycosidic linkages in
the disaccharides 22, 28 and 37 followed from the character-
1
istic values of J1Ј,2Ј (7.5–8.0 Hz) in H NMR spectra. For the
α--fucoside 40 the corresponding value is J1Ј,2Ј = 3.0 Hz.
74
J. Chem. Soc., Perkin Trans. 1, 2001, 72–81

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Scheme 5 Reagents: i, Me2NH, MeCN–THF; ii, CCl3CN, DBU,
CH2Cl2; iii, TMS triflate, MS 4 Å, CH2Cl2; iv, (a) triimidazolylphos-
phine, MeCN; (b) Et3NHHCO3, water (pH 7); v, (a) dec-9-en-1-ol,
trimethylacetyl chloride, pyridine; (b) I2, pyridine–water; vi, NaOMe,
MeOH.
Scheme 4 Reagents: i, Hg(CN)2, HgBr2, MeCN–PhMe; ii, (a) aq.
TFA, CHCl3; (b) H2SO4, Ac2O; iii, Me2NH, MeCN–THF; iv, (a) triimi-
dazolylphosphine, MeCN; (b) Et3NHHCO3, water (pH 7); v, (a) dec-9-
en-1-ol, trimethylacetyl chloride, pyridine; (b) I2, pyridine–water; vi,
NaOMe, MeOH.
saccharides 6–10 were prepared from the derivatives 15, 26, 32,
41 and 44, respectively, by de-O-acylation with 0.05 mol dmϪ3
methanolic sodium methoxide in 88–100% yield.
The structures of the compounds 6–10 and the protected
phosphodiesters 15, 26, 32, 41 and 44 were confirmed by NMR
and mass spectrometric data. The 31P NMR spectra exhibited
single signals [δP between Ϫ1.35 and Ϫ1.96 for the deprotected
compounds 6–10 (in D2O) and between Ϫ1.67 and Ϫ3.12 for
the protected phosphodiesters (in CDCl3)], which are charac-
teristic for glycoside-linked phosphodiesters.3–6,8–10 The
presence of a (1→1)-phosphodiester linkage at the reducing
terminus of each of the disaccharides 6–10 was confirmed by
the C-1 and C-2 signals of the corresponding monosaccharide
residue and the dec-9-enyl unit in the 13C NMR spectra (Table
1). These signals were shifted as a result of the α- and β-effects
of phosphorylation and were coupled with phosphorus (or
broadened).
The α-configuration of the -glucopyranosyl phosphate
fragments in compounds 6 and 15 was evident from the charac-
1
teristic values of J1,2 = 3.4–3.5 Hz in the H NMR spectra (see
Experimental section). The α-configuration of the -altro-
pyranosyl residue in the phosphodisaccharide 7 followed from
1
the characteristic value† of JC,H = 171.3 Hz for the signal of
C-1 and the characteristic position of the C-5 resonance of
-Altp in the 13C NMR spectrum (Table 1). The chemical shift
Scheme 6 Reagents: i, Me2NH, MeCN–THF; ii, (a) triimidazolyl-
phosphine, MeCN; (b) Et3NHHCO3, water (pH 7); iii, (a) dec-9-en-1-
ol, trimethylacetyl chloride, pyridine; (b) I2, pyridine–water; iv,
NaOMe, MeOH.
† The value of 1JC1,H1 ≈ 170 Hz is typical for α--derivatives. For the β-
-glycosyl residues the value is about 160 Hz: for β--Galp in com-
pound 7, 1JC1Ј,H1Ј = 162.5 Hz (Table 1) (see also refs. 3, 4, 9 and 16).
J. Chem. Soc., Perkin Trans. 1, 2001, 72–81
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Table 1 13C and 31P NMR data [δC and δP in ppm; JC,P and JC,H in Hz; spectra recorded in D2O] and ESMS(Ϫ) data (m/z) for the phosphodi-
saccharides 6–10
Residue
Atom
6a
7a
8b
9a
10a
Dec-9-enyl
OCH2CH2
OCH2CH2
67.20d
JC,P 4.0
31.15d
JC,P 9.0
140.32
115.10
95.71d
JC,P 6.9
67.82d
JC,P ≈6
30.96d
JC,P 8.8
141.64
115.09
96.76br
67.76d
JC,P ≈6
30.87d
JC,P 5.9
141.54
115.00
96.70br
67.45br
30.95br
67.01br
31.03d
JC,P 8.3
141.52
114.98
96.78d
JC,P 5.8
JC,H 170.5
71.29d
JC,P 7.5
70.54
76.98
73.30
61.30
102.08
JC,H 171.0
69.64
71.23
72.57
–CH᎐
140.87
115.00
96.69br
᎐
᎐CH2
᎐
Aldose
C-1
JC,H 171.3
71.54d
JC,P 10.0
70.95
74.38
69.78
JC,H 169.7
71.18d
JC,P 6.9
69.61
82.62
69.44
JC,H 171.0
70.89d
JC,P 7.2
69.76
77.20
73.12
C-2
72.10d
JC,P 7.7
72.23
78.77
72.39
60.65
103.85
C-3
C-4
C-5
C-6
C-1Ј
61.53
17.82
61.10
AldoseЈ
105.04
JC,H 162.5
71.96
73.67
69.96
76.21
62.20
Ϫ1.35
104.27
JC,H 161.0
72.09
73.61
69.72
76.37
62.18
Ϫ1.50
103.87
JC,H 160.5
71.45
73.71
72.12
72.01
16.34
Ϫ1.41
C-2Ј
C-3Ј
C-4Ј
C-5Ј
C-6Ј
P
71.83
73.58
69.51
76.25
61.93
Ϫ1.96
68.22
16.42
Ϫ1.66
Phosphate
m/zc
559.34
558.90
543.25
543.10
543.10
a Additional signals of Et3NHϩ [δC 9.20–9.37 (CH3) and δC 47.41–47.63 (CH2)] were present. a,b Additional signals of CCH2C [δC 25.95–26.26, 29.19–
30.09 and 34.16–34.44] were present. c Corresponds to the pseudomolecular ions [M Ϫ Et3N Ϫ H]Ϫ. For compounds 6 and 7 (triethylammonium
salt), C28H56NO14P requires M, 661.34 (expected m/z, 559.14); for compounds 8–10 (triethylammonium salt), C28H56NO13P requires M, 645.35
(expected m/z, 534.15).
of the C-5 signal (δC 69.78) is fairly close to that of C-5 (δC
70.00)‡ of methyl α--altropyranoside.17
Bruker AM-200 and AM-500 spectrometers for solutions in
CDCl3, unless otherwise indicated. Chemical shifts (δ in ppm)
1
The α-configuration of the D-mannopyranosyl phosphate
fragments in compounds 9 and 10 and of the -rhamno-
pyranosyl phosphate in compound 8 was confirmed by 1) the
are given relative to those for Me4Si (for H and 13C) and
external aq. 85% H3PO4 (for 31P); J-values are given in Hz. ES
mass spectra were recorded with a Micromass Quattro system
(Micromass Biotech, UK). TLC was performed on Kieselgel
60 F254 (Merck) with A, toluene–ethyl acetate (95:5); B,
toluene–ethyl acetate (9:1); C, toluene–ethyl acetate (7:3); D,
toluene–ethyl acetate (3:7); E, dichloromethane–methanol
(95:5); F, chloroform–methanol (8:2); and G, chloroform–
methanol–water (10:10:3) as developers and detection under
UV light or by charring with sulfuric acid–water–ethanol
(15:85:5). Flash-column chromatography (FCC) was per-
formed on Kieselgel 60 (0.040–0.063 mm) (Merck). Dichloro-
methane, acetonitrile and toluene were freshly distilled from
CaH2. Solutions worked up were concentrated under reduced
pressure at < 40 ЊC.
1
characteristic values† of JC,H for the signals of C-1 and 2) the
characteristic positions of the C-3 and C-5 resonances of
-Manp and -Rhap residues, respectively, in the 13C NMR
spectra (see Table 1). The chemical shifts of the signals of
C-3 and -5 of -Manp and C-3 of -Rhap (i.e., 6-deoxy--
mannose) are close to those of C-3 and C-5 of α--manno-
pyranosyl phosphate18 taking into account the influence of the
glycosyl substituents at position 4. The chemical shift of C-5
resonance (δC 69.44) of -Rhap in compound 8 is very close to
that of C-5 (δC 69.40)§ of methyl α--rhamnopyranoside.17
The α-configuration of the glycosyl phosphate linkages in
the protected derivatives 26, 32, 41 and 44 followed from the
characteristic positions of 1-, 3- and 5-H resonances in their 1H
NMR spectra (see Experimental section).
The molecular masses of the phosphodiesters 6–10, 15, 26,
32, 41 and 44 were confirmed by electrospray mass spec-
trometry. The signals in the ES(Ϫ) mass spectra corresponded
to the pseudomolecular ions for the disaccharide phosphates
(see Table 1 and Experimental section). A biochemical eval-
uation of compounds 6–10 will be published elsewhere19 in due
course.
2,3,4,6-Tetra-O-acetyl-ꢁ-D-galactopyranosyl-(1→4)-2,3,6-tri-O-
acetyl-ꢀ,ꢁ-D-glucopyranose 12
To a solution of 2,3,4,6-tetra-O-acetyl-β--galactopyranosyl-
(1→4)-1,2,3,6-tetra-O-acetyl-α,β--glucopyranose 11 (1 g, 1.47
mmol) [prepared by standard acetylation of α-lactose with
Ac2O in pyridine at 0 ЊC; δH (200 MHz) (inter alia) 1.94, 1.98,
2.10, 2.13 and 2.15 (15 H, 5 × s, 5 × Ac), 2.03 (9 H, s, 3 × Ac),
3.79 (t, J3,4 = J4,5 = 9.6, 4-Hα), 3.86 (1 H, dt, J5Ј,6Ј 6.6, 5Ј-H),
3.93–4.17 (4 H, m, 5-H, 6-Ha and 6Ј-H2), 4.42 (1 H, dd, J5,6b 1.6,
J6a,6b 12.4, 6-Hb), 4.45 (d, J1Ј,2Ј 7.9, 1Ј-Hα), 4.54 (d, J1Ј,2Ј 8.2,
1Ј-Hβ), 4.94 (1 H, dd, J3Ј,4Ј 3.4, 3Ј-H), 4.98 (dd, J2,3 9.9, 2-Hα),
5.10 (dd, J2Ј,3Ј 10.6, 2Ј-Hα), 5.33 (1 H, dd, J4Ј,5Ј 0.5, 4Ј-H), 5.44
(dd, 3-Hα), 5.65 (d, J1,2 7.1, 1-Hβ) and 6.22 (d, J1,2 3.6, 1-Hα);
α:β ≈ 7:1] in acetonitrile (6 cm3) was added 2 mol dmϪ3
Me2NH in THF (4 cm3; 7.96 mmol) and the mixture was kept at
rt with monitoring by TLC (solvent D). After 4–9 h the mixture
was concentrated to dryness and acetonitrile was evaporated
off from the residue. FCC [ethyl acetate–toluene, (2:8) →
(8:2)] of the residue gave the disaccharide α,β-hemiacetal 12
Experimental
General procedures
Optical rotations were measured with a Perkin-Elmer 141
polarimeter; [α]D-values are given in units of 10Ϫ1 deg cm2 gϪ1.
NMR spectra (1H at 200 and 500 MHz, 13C{1H} at 50.3 and 125
MHz, and 31P{1H} at 81 and 202.5 MHz) were recorded with
‡ For methyl β--altropyranoside, δC-5 = 75.60.17
§ For methyl β--rhamnopyranoside, δC-5 = 73.60.17
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(0.779 g, 83%) as an amorphous solid, [α]D25 ϩ35.2 (c 1.06,
CHCl3) (Found: C, 48.8; H, 5.6. C26H36O18 requires C, 49.1; H,
5.7%); δH (200 MHz) (inter alia) 1.96, 2.03, 2.04, 2.05, 2.07, 2.12
and 2.15 (21 H, 7 × s, 7 × Ac), 3.75 (dd, J4,5 9.3, 4-Hα), 3.86 (1
H, dt, J5Ј,6Ј 6.3, 5Ј-H), 4.00–4.22 (4 H, m, 5-H, 6-Ha and 6Ј-H2),
4.47 (d, J1Ј,2Ј 7.7, 1Ј-Hβ), 4.48 (1 H, dd, J5,6b 3.4, J6a,6b 11.2,
6-Hb), 4.49 (d, J1Ј,2Ј 7.9, 1Ј-Hα), 4.76 (m, 1- and 2-Hβ), 4.81 (dd,
2-Hα), 4.94 (1 H, dd, J3Ј,4Ј 3.2, 3Ј-H), 5.09 (dd, J2Ј,3Ј 10.6, 2Ј-Hβ),
5.11 (dd, J2Ј,3Ј 10.5, 2Ј-Hα), 5.22 (t, J2,3 = J3,4 = 9.3, 3-Hβ), 5.34
(1 H, dd, J4Ј,5Ј 0.5, 4Ј-H), 5.36 (d, J1,2 3.4, 1-Hα) and 5.51 (t,
J2,3 = J3,4 = 9.7, 3-Hα); α:β = 4:1.
diester 15 (144 mg, 96%) as an amorphous solid, [α]D25 ϩ37
(c 0.96, CHCl3); δH (200 MHz) 1.20–1.32 (10 H, m, 5 × CH2),
1.29 (9 H, t, 3 × MeCH2), 1.57 (2 H, tt, J 6.9, OCH2CH2CH2),
1.93, 2.01, 2.02, 2.09 and 2.12 (15 H, 5 × s, 5 × Ac), 2.00 (8 H, s,
2 × Ac and m, CH2CH2CH=), 3.03 (6 H, q, 3 × MeCH2), 3.76
(1 H, t, J3,4 = J4,5 = 9.6, 4-H), 3.83 (1 H, t, J5Ј,6Ј 6.7, 5Ј-H), 3.85
(2 H, m, OCH2CH2), 3.98–4.12 (3 H, m, 6-Ha and 6Ј-H2), 4.17
(1 H, ddd, J5,6a 2.4, 5-H), 4.41 (1 H, d, J1Ј,2Ј 7.7, 1Ј-H), 4.45 (1 H,
dd, J5,6b 1.3, J6a,6b 12.0, 6-Hb), 4.83 (1 H, ddd, J1,2 3.4, J2,P 1.9,
2-H), 4.90 (1 H, dd, 3Ј-H), 4.86 (1 H, dd, 2JH,H 1.4, 3JH,H-Z 10.3,
3
HCH᎐CH), 4.95 (1 H, dd, J
17.0, HCH᎐CH), 5.07 (1 H,
᎐
᎐
H,H-E
dd, J2Ј,3Ј 10.4, 2Ј-H), 5.31 (1 H, d, J3Ј,4Ј 3.2, 4Ј-H), 5.45 (1 H, t,
J2,3 9.6, 3-H), 5.63 (1 H, dd, J1,P 8.0, 1-H) and 5.77 (1 H, ddt,
2,3,4,6-Tetra-O-acetyl-ꢁ-D-galactopyranosyl-(1→4)-2,3,6-tri-O-
acetyl-ꢀ-D-glucopyranosyl hydrogenphosphonate, triethyl-
ammonium salt 14
JH,CH 6.7, CH CH᎐CH ); δ Ϫ1.67; ESMS(Ϫ): m/z 853.0
᎐
2
2
P
2
(100%, [M Ϫ Et3N Ϫ H]–) (expected m/z, 853.22. C42H70NO21P
requires M, 955.42).
To a stirred solution of imidazole (0.65 g, 9.56 mmol) in
acetonitrile (10 cm3) at 0 ЊC was added phosphorus trichloride
(0.25 cm3, 2.87 mmol) followed by Et3N (1.4 cm3, 10.04 mmol).
The mixture was stirred for 20 min, after which a solution of
compound 12 (0.304 g, 0.478 mmol) in MeCN (10 cm3) was
added dropwise over a period of 10–15 min at 0 ЊC. The mix-
ture was stirred at rt for 30–40 min and quenched with 1 mol
dmϪ3 triethylammonium (TEA) hydrogen carbonate (pH 7;
4 cm3). The clear solution was stirred for 15 min, CH2Cl2 (100
cm3) was added and the organic layer was washed in turn with
ice-cold water (2 × 40 cm3) and cold 0.5 mol dmϪ3 TEA hydro-
gen carbonate (2 × 40 cm3), dried by filtration through cotton
wool, and concentrated to give the α,β-(H-phosphonate) 13,
δP 0.43 (Pα) and 1.20 (Pβ); δH (200 MHz) (inter alia) 5.20 (dd, J1,2
7.7, J1,P 9.1, 1-Hβ), 5.67 (dd, J1,2 3.4, J1,P 8.8, 1-Hα), 6.88 (d, 1JH,P
644.0, H-Pβ) and 6.91 (d, 1JH,P 637.8, H-Pα); α:β = 4:1.
Dec-9-enyl ꢁ-D-galactopyranosyl-(1→4)-ꢀ-D-glucopyranosyl
phosphate, triethylammonium salt 6
To a solution of compound 15 (138 mg) in MeOH (15 cm3) was
added 0.5 mol dmϪ3 methanolic NaOMe (1.7 cm3). The mixture
(now 0.05 mol dmϪ3 in NaOMe) was kept at room temperature
for 1 h, whereafter it was deionized with Dowex 50W-X4 (Hϩ)
resin, filtered, and immediately neutralized with Et3N. The solu-
tion was concentrated and methanol was evaporated off from
the residue. The phosphodiester 6 (96 mg, 100%) was thereby
obtained as an amorphous solid, [α]D25 ϩ54.5 (c 1, MeOH);
δH (200 MHz; D2O) (inter alia) 1.16 (9 H, t, 3 × MeCH2), 1.19
(10 H, m, 5 × CH2), 1.48 (2 H, tt, J 6.9, OCH2CH2CH2), 1.91
(2 H, dt, J 6.6, CH CH CH᎐), 3.06 (6 H, q, 3 × MeCH ), 4.34
᎐
2
2
2
(1 H, d, J1Ј,2Ј 7.6, 1Ј-H), 5.33 (1 H, dd, J1,2 3.5, J1,P 7.1, 1-H)
The residue was dissolved in CH3CN (15 cm3) and anhydrous
H3PO3 (0.67 g, 8.17 mmol) was added. The mixture was stirred
at rt for 19 h, then diluted with CH2Cl2 (100 cm3) and washed
successively with cold saturated aq. NaHCO3 (2 × 40 cm3) and
cold 0.5 mol dmϪ3 aq. TEA hydrogen carbonate (2 × 40 cm3).
The organic phase (containing the hemiacetal 12) was dis-
carded. The aqueous washings were then combined, and
extracted with CH2Cl2 (4 × 40 cm3). The combined organic
washings were dried by filtration through cotton wool, and
concentrated to produce the α-hydrogenphosphonate 14 (0.184
g, 48%) as a chromatographically homogeneous amorphous
solid, [α]D26 ϩ41.8 (c 0.97, CHCl3); δH (200 MHz) 1.32 (9 H, t,
3 × MeCH2), 1.92, 2.00, 2.02, 2.07 and 2.10 (15 H, 5 × s,
5 × Ac), 1.99 (6 H, s, 2 × Ac), 3.04 (6 H, q, 3 × MeCH2), 3.74
(1 H, t, J3,4 = J4,5 = 9.6, 4-H), 3.84 (1 H, t, J5Ј,6Ј 6.7, 5Ј-H),
3.97–4.20 (4 H, m, 5-H, 6-Ha and 6Ј-H2), 4.41 (1 H, d, J1Ј,2Ј 7.7,
1Ј-H), 4.42 (1 H, br d, J6a,6b 10.9, 6-Hb), 4.84 (1 H, dd, J1,2 3.4,
2-H), 4.90 (1 H, dd, J3Ј,4Ј 3.3, 3Ј-H), 5.06 (1 H, dd, J2Ј,3Ј 10.3,
2Ј-H), 5.30 (1 H, d, 4Ј-H), 5.44 (1 H, t, J2,3 9.6, 3-H), 5.67 (1 H,
dd, J1,P 8.8, 1-H) and 6.89 (1 H, d, JH,P 637.8, HP); δP 0.77;
ESMS(Ϫ) data: m/z 698.9 (100%, [M Ϫ Et3N Ϫ H]Ϫ) (expected
m/z, 699.08. C32H52NO20P requires M, 801.28).
and 5.71 (1 H, ddt, JH,CH 6.6, JH,H-Z 10.2, JH,H-E 17.0, CH2-
2
CH᎐CH ); δ , δ and ESMS(Ϫ) data: see Table 1.
᎐
2
C
P
Benzyl 2-O-benzoyl-4,6-O-isopropylidene-ꢀ-D-mannopyranoside
17
To a stirred solution of benzyl 4,6-O-isopropylidene-α--
mannopyranoside 16 (3.1 g, 10 mmol) [prepared from benzyl
α--mannopyranoside and 2-methoxypropene in 85% yield, [α]D25
ϩ85 (c 1, CHCl3), Rf 0.3 (solvent E) (Found: C, 61.8; H, 7.2.
C16H22O6 requires C, 61.9; H, 7.1%) as described for the prepar-
ation of methyl 4,6-O-isopropylidene-α--mannopyranoside11]
and BzCN (1.57 g, 12 mmol) in acetonitrile (20 cm3) was added
Et3N (0.025 cm3). After 30 min, methanol was added, the reac-
tion mixture was concentrated, and toluene was evaporated off
from the residue. FCC (solvent A) gave the monobenzoate 17
(3.15 g, 76%) as an amorphous solid, [α]D25 ϩ48 (c 1, CHCl3); Rf
0.2 (solvent B) (Found: C, 66.25; H, 6.3. C23H26O7 requires C,
66.65; H, 6.3%); δH (200 MHz) 1.49 and 1.61 (6 H, 2 × s,
2 × Me), 3.73-3.93 (3 H, m, 5-H and 6-H2), 4.07 (1 H, t,
J3,4 = J4,5 = 9.0, 4-H), 4.26 (1 H, dd, J2,3 3.4, 3-H), 4.53 and 4.73
(2 H, AB q, J 11.7, CH2Ph), 5.00 (1 H, d, J1,2 1.3, 1-H), 5.50
(1 H, dd, 2-H) and 7.15–8.15 (10 H, m, 2 × Ph).
Dec-9-enyl 2,3,4,6-tetra-O-acetyl-ꢁ-D-galactopyranosyl-(1→4)-
2,3,6-tri-O-acetyl-ꢀ-D-glucopyranosyl phosphate, triethyl-
ammonium salt 15
Benzyl 2,3-di-O-benzoyl-4,6-O-isopropylidene-ꢀ-D-altropyrano-
side 19
A mixture of the H-phosphonate 14 (126 mg, 0.16 mmol) and
dec-9-en-1-ol (0.056 cm3, 0.31 mmol) was dried by evaporation
of pyridine (3 × 2 cm3) therefrom. The residue was dissolved in
pyridine (1 cm3), trimethylacetyl chloride (0.048 cm3, 0.39
mmol) was added, and the mixture was stirred at rt for 10–15
min, whereafter a freshly prepared solution of iodine (80 mg,
0.314 mmol) in pyridine–water (95:5; 2 cm3) was added. After
30 min, CH2Cl2 was added and the solution was washed succes-
sively with ice-cold 1 mol dmϪ3 aq. Na2S2O3 and cold 0.5 mol
dmϪ3 aq. TEA hydrogen carbonate, dried by filtration through
cotton wool, and concentrated. FCC [CH2Cl2–MeOH–Et3N,
(99:0:1) → (89:10:1)] of the residue gave the phospho-
Triflic anhydride (2.05 cm3, 12.2 mmol) was added dropwise to
a cooled (0 ЊC) stirred solution of compound 17 (2.53 g, 6.11
mmol) in CH2Cl2 (50 cm3) containing pyridine (3.85 cm3, 48.9
mmol), and then the reaction mixture was allowed to warm to
rt. After 1 h, the mixture was diluted with CH2Cl2, washed
successively with ice-cold 0.1 mol dmϪ3 HCl, ice-cold saturated
aq. NaHCO3 and water, and dried by filtration through cotton
wool. The filtrate was concentrated to dryness and toluene was
evaporated off from the residue to produce the triflate 18 [Rf 0.5
(solvent B), δH (200 MHz) 1.45 and 1.58 (6 H, 2 × s, 2 × Me),
3.83–3.93 (3 H, m, 5-H and 6-H2), 4.28 (1 H, t, J3,4 = J4,5 = 9.1,
4-H), 4.57 and 4.72 (2 H, AB q, J 11.7, CH2Ph), 5.02 (1 H, d,
J. Chem. Soc., Perkin Trans. 1, 2001, 72–81
77

View Article Online
J1,2 1.1, 1-H), 5.25 (1 H, dd, J2,3 3.6, 3-H), 5.65 (1 H, dd, 2-H)
and 7.10–8.10 (10 H, m, 2 × Ph)].
4.39 (dd, J4,5 8.5, 4-Hα), 4.42 (dt, J5,6a = J5,6b = 3.0, 5-Hβ), 4.52
(dd, J5,6a 3.0, J6a,6b 11.7, 6-Ha), 4.61 (d, J1Ј,2Ј 7.0, 1Ј-Hα), 4.67 (d,
J1Ј,2Ј 7.0, 1Ј-Hβ), 4.70–4.78 (m, 5-Hα and 6-Hb), 4.92 (dd, J3Ј,4Ј
3.0, 3Ј-Hα), 4.95 (dd, J3Ј,4Ј 3.0, 3Ј-Hβ), 5.13 (dd, J2Ј,3Ј 9.0, 2Ј-Hα),
5.17 (dd, J2Ј,3Ј 9.0, 2Ј-Hβ), 5.22 (d, 4Ј-Hα), 5.26 (d, 4Ј-Hβ), 5.30
(br s, 1-Hβ), 5.39 (br s, 1-Hα), 5.46 (d, 2-Hβ), 5.51 (d, 2-Hα), 5.69
(t, J2,3 = J3,4 = 2.8, 3-Hβ), 5.79 (t, J2,3 = J3,4 = 2.8, 3-Hα) and 7.20–
8.20 (15 H, m, 3 × Ph); α:β = 0.8:1].
A solution of tetrabutylammonium benzoate (3.63 g, 10
mmol; dried beforehand by evaporation of anhydrous toluene
therefrom) in toluene (20 cm3) was added to a solution of the
triflate 18 in the same solvent (30 cm3). The reaction mixture
was stirred at 60 ЊC for 7 h, then diluted with CH2Cl2, washed
successively with saturated aq. NaHCO3 and water, dried by
filtration through cotton wool and concentrated. FCC (solvent
A) gave the altroside 19 (2.3 g, 73%), mp 142–144 ЊC (from
diethyl ether–hexane); [α]D25 ϩ16 (c 1, CHCl3); Rf 0.5 (solvent B)
(Found: C, 69.8; H, 5.9. C30H30O8 requires C, 69.5; H, 5.8%);
δH (200 MHz) 1.35 and 1.61 (6 H, 2 × s, 2 × Me), 3.90 (1 H, t,
J5,6a = J6a,6b = 9.6, 6-Ha), 3.98 (1 H, dd, J5,6b 5.7, 6-Hb), 4.26
(1 H, dd, J4,5 9.6, 4-H), 4.43 (1 H, dt, 5-H), 4.53 and 4.82 (2 H,
AB q, J 11.1, CH2Ph), 5.03 (1 H, d, J1,2 1.1, 1-H), 5.39 (1 H, dd,
2-H), 5.55 (1 H, t, J2,3 = J3,4 = 3.0, 3-H) and 7.15–8.15 (15 H, m,
3 × Ph).
The reaction of the compound 24 (0.39 g, 0.474 mmol) with
PCl3 (0.165 cm3, 1.89 mmol), imidazole (0.45 g, 6.62 mmol) and
Et3N (0.99 cm3, 7.09 mmol) in CH3CN (10 cm3), followed by
hydrolysis with 1 mol dmϪ3 aq. TEA hydrogen carbonate (2.5
cm3), was accomplished as described for the preparation of the
disaccharide H-phosphonate 13. After work-up, the solution
was concentrated and acetonitrile was evaporated off from the
residue. The residue was dissolved in the same solvent (5 cm3)
and anhydrous H3PO3 (0.39 g, 4.73 mmol) was added to the
solution. The reaction mixture was kept at rt for 20 h, then
diluted with CH2Cl2 (50 cm3) and washed successively with
saturated aq. NaHCO3 and 0.5 mol dmϪ3 aq. TEA hydrogen
carbonate, dried by filtration through cotton wool, and con-
centrated. FCC [CH2Cl2–MeOH, (99:1) → (80:20)] gave the
H-phosphonate 23 (0.175 g, 35% from the disaccharide 22) as
an amorphous solid, [α]D25 ϩ1 (c 1, CHCl3); Rf 0.35 (solvent F); δH
(200 MHz) 1.20 (9 H, t, 3 × MeCH2), 1.91, 1.92, 1.93 and 2.02
(12 H, 4 × s, 4 × Ac), 2.91 (6 H, q, 3 × MeCH2), 3.80–3.88 (2 H,
m, 5Ј-H and 6Ј-Ha), 3.93 (1 H, dd, J5Ј,6bЈ 7.8, J6aЈ,6bЈ 13.5, 6Ј-Hb),
4.35 (1 H, dd, J4,5 9.6, 4-H), 4.46 (1 H, dd, J6a,6b 11.6, 6-Ha), 4.64
(1 H, d, J1Ј,2Ј 7.7, 1Ј-H), 4.71 (1 H, dd, J5,6b 1.0, 6-Hb), 4.88 (1 H,
ddd, J5,6a 3.7, 5-H), 4.91 (1 H, dd, J3Ј,4Ј 3.2, 3Ј-H), 5.13 (1 H, dd,
J2Ј,3Ј 10.6, 2Ј-H), 5.23 (1 H, d, 4Ј-H), 5.44 (1 H, d, 2-H), 5.67 (1
H, t, J2,3 = J3,4 = 2.8, 3-H), 5.72 (1 H, d, J1,P 8.5, 1-H), 7.02 (1 H,
d, JH,P 640.0, HP) and 7.40–8.20 (15 H, m, 3 × Ph); δP 0.58;
ESMS(Ϫ): m/z 884.9 (100%, [M Ϫ Et3N Ϫ H]Ϫ) (expected m/z,
885.008. C47H58NO20P requires M, 987.208). Also isolated was
the disaccharide hemiacetal 24 (0.2 g, 49% recovery).
Benzyl 2,3,6-tri-O-benzoyl-ꢀ-D-altropyranoside 20
A solution of the altroside 19 (2.49 g, 4.8 mmol) in 80% aq.
acetic acid (50 cm3) was heated at 60 ЊC for 1 h, whereafter the
mixture was concentrated and toluene was twice evaporated off
from the residue. The residue was dissolved in acetonitrile (50
cm3) and BzCN (0.63 g, 4.82 mmol) and Et3N (0.025 cm3) were
added to the solution. After 30 min, methanol was added, the
reaction mixture was concentrated, and toluene was evaporated
off from the residue. FCC (solvent A) gave the tribenzoate 20
(1.87 g, 67%), mp 140–142 ЊC (from diethyl ether–hexane);
[α]D25 Ϫ6.5 (c 1, CHCl3); Rf 0.25 (solvent B) (Found: C, 70.4; H,
5.1. C34H30O9 requires C, 70.1; H, 5.2%); δH (200 MHz;
CDCl3 ϩ D2O) 4.28 (1 H, dd, J4,5 9.7, 4-H), 4.48 (1 H, ddd, J5,6a
2.3, 5-H), 4.58 and 4.83 (2 H, AB q, J 10.8, CH2Ph), 4.66 (1 H,
dd, J6a,6b 12.0, 6-Ha), 4.78 (1 H, dd, J5,6b 4.0, 6-Hb), 5.10 (1 H, d,
J1,2 1.0, 1-H), 5.42 (1 H, dd, 2-H), 5.62 (1 H, t, J2,3 = J3,4 = 3.2,
3-H) and 7.15–8.15 (20 H, m, 4 × Ph).
Dec-9-enyl 2,3,4,6-tetra-O-acetyl-ꢁ-D-galactopyranosyl-(1→4)-
2,3,6-tri-O-benzoyl-ꢀ-D-altropyranosyl phosphate, triethyl-
ammonium salt 26
Benzyl 2,3,4,6-tetra-O-acetyl-ꢁ-D-galactopyranosyl-(1→4)-
2,3,6-tri-O-benzoyl-ꢀ-Dl-altropyranoside 22
A solution of acetobromogalactose 21 (1.03 g, 2.5 mmol) in
CH2Cl2 (15 cm3) was added dropwise to a stirred mixture of the
altroside 20 (0.73 g, 1.25 mmol), Ag2CO3 (1.37 g, 5.0 mmol),
AgOTf (0.64 g, 2.5 mmol) and freshly activated molecular
sieves 4 Å (powder, 5 g) in boiling dichloromethane (30 cm3).
The reaction mixture was stirred under reflux for 2.5 h and then
at rt for 20 h. The solids were filtered off and the filtrate was
concentrated. FCC [diethyl ether–hexane, (1:1) → (2:1)]
gave the disaccharide 22 (0.59 g, 52%) as an amorphous solid,
[α]D25 ϩ12 (c 1, CHCl3); Rf 0.45 (solvent C) (Found: C, 63.1; H,
5.4. C48H48O18 requires C, 63.15; H, 5.3%); δH (200 MHz) 1.91
(6 H, s, 2 × Ac), 1.93 and 2.01 (6 H, 2 × s, 2 × Ac), 3.82–3.99 (3
H, m, 5Ј-H and 6Ј-H2), 4.32 (1 H, dd, J4,5 9.5, 4-H), 4.44 (1 H,
dd, J5,6a 4.5, J6a,6b 12.5, 6-Ha), 4.52 and 4.81 (2 H, AB q, J 11.6,
CH2Ph), 4.58–4.70 (3 H, m, 1Ј-, 5-H and 6-Hb), 4.91 (1 H, dd,
J2Ј,3Ј 10.5, 3Ј-H), 5.02 (1 H, br s, 1-H), 5.15 (1 H, dd, J1Ј,2Ј 7.5,
2Ј-H), 5.25 (1 H, d, J3Ј,4Ј 3.5, 4Ј-H), 5.46 (1 H, d, 2-H), 5.66 (1 H,
t, J2,3 = J3,4 = 3.3, 3-H) and 7.15–8.15 (20 H, m, 4 × Ph).
This compound was prepared by condensation of the glycobio-
syl H-phosphonate 23 (98 mg, 0.10 mmol) and dec-9-en-1-ol
(0.053 cm3, 0.30 mmol) in pyridine (1 cm3) in the presence of
trimethylacetyl chloride (0.037 cm3, 0.30 mmol), followed by
oxidation with iodine (51 mg, 0.20 mmol) in pyridine–water
(95:5; 2 cm3) as described for the synthesis of the phosphodi-
ester 15. FCC [CH2Cl2–MeOH, (99:1) → (80:20)] gave the
phosphodiester 26 (85 mg, 75%) as an amorphous solid, [α]D25 ϩ2
(c 1, CHCl3); Rf 0.5 (solvent F); δH (200 MHz) 1.25 (19 H, m,
3 × MeCH2 and 5 × CH2), 1.48 (2 H, tt, J 6.9, OCH2CH2CH2),
1.95 (6 H, s, 2 × Ac), 1.97 and 2.00 (6 H, 2 × s, 2 × Ac), 2.03
(2 H, m, CH CH CH᎐), 2.95 (6 H, q, 3 × MeCH ), 3.74–3.96
᎐
2
2
2
(5 H, m, 5Ј-H, 6Ј-H2 and OCH2CH2), 4.38 (1 H, dd, J4,5 9.6,
4-H), 4.46 (1 H, dd, J5,6a 3.0, J6a,6b 11.8, 6-Ha), 4.64 (1 H, d, J1Ј,2Ј
7.8, 1Ј-H), 4.72 (1 H, dd, J5,6b 1.0, 6-Hb), 4.87–4.95 (3 H, m, 3Ј-,
2
3
5-H and HCH᎐CH), 4.98 (1 H, dd, JH,H 1.6, JH,H-E 16.8,
᎐
HCH᎐CH), 5.12 (1 H, dd, J
10.1, 2Ј-H), 5.23 (1 H, d, J3Ј,4Ј
᎐
2Ј,3Ј
3.1, 4Ј-H), 5.50 (1 H, d, J2,3 3.0, 2-H), 5.64 (1 H, d, J1,P 7.7, 1-H),
3
5.68 (1 H, dd, J3,4 3.5, 3-H), 5.80 (1 H, ddt, JH,CH 6.6, JH,H-Z
2
2,3,4,6-Tetra-O-acetyl-ꢁ-D-galactopyranosyl-(1→4)-2,3,6-tri-O-
benzoyl-ꢀ-D-altropyranosyl hydrogenphosphonate, triethyl-
ammonium salt 23
10.9, CH CH᎐CH ) and 7.40–8.25 (15 H, m, 3 × Ph); δ Ϫ2.79;
᎐
2 2 P
ESMS(Ϫ): m/z 1039.0 (100%, [M Ϫ Et3N Ϫ H]Ϫ) (expected
m/z, 1039.14. C57H76NO21P requires M, 1141.344).
A solution of the disaccharide 22 (0.455 g, 0.499 mmol) in THF
(5 cm3) containing 20% Pd(OH)2/C (200 mg) was shaken under
a slight overpressure of H2 at rt for 2 h. The catalyst was filtered
off through a Celite pad and the filtrate was concentrated to
give the α,β-hemiacetal 24 (0.39 g, 95%) as an amorphous solid
[Rf 0.3 (solvent C); δH (500 MHz) 1.89–2.03 (12 H, m, 4 × Ac),
3.78–3.92 (3 H, m, 5Ј-H and 6Ј-H2), 4.30 (dd, J4,5 8.5, 4-Hβ),
Dec-9-enyl ꢁ-D-galactopyranosyl-(1→4)-ꢀ-D-altropyranosyl
phosphate, triethylammonium salt 7
To a solution of compound 26 (50 mg) in MeOH (1.8 cm3) was
added 0.5 mol dmϪ3 methanolic NaOMe (0.2 cm3). The mixture
(now 0.05 mol dmϪ3 in NaOMe) was kept at 0 ЊC for 16 h and
then at room temperature for 8 h, whereafter it was deionized
78
J. Chem. Soc., Perkin Trans. 1, 2001, 72–81

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with Dowex 50W-X4(Hϩ) resin, filtered and immediately
neutralized with Et3N. After concentration, water (3 × 5 cm3)
was evaporated off from the residue to remove methyl benzoate.
The phosphodiester 7 (28 mg, 96%) was thereby obtained as an
amorphous solid, [α]D25 ϩ36 (c 1, MeOH); Rf 0.65 (solvent G);
δH (200 MHz; D2O) (inter alia) 1.15 (9 H, t, 3 × MeCH2), 1.23
(10 H, m, 5 × CH2), 1.52 (2 H, tt, J 6.9, OCH2CH2CH2), 1.94
2.12 and 2.14 (18 H, 6 × s, 6 × Ac), 3.59 (1 H, t, J3,4 = J4,5 = 9.4,
4-H), 3.87 (1 H, t, J5Ј,6aЈ = J5Ј,6bЈ = 6.5, 5Ј-H), 4.00 (1 H, dq, 5-H),
4.01 (1 H, dd, 6Ј-Ha), 4.16 (1 H, dd, J6aЈ,6bЈ 11.0, 6Ј-Hb), 4.57
(1 H, d, J1Ј,2Ј 7.8, 1Ј-H), 4.97 (1 H, dd, J3Ј,4Ј 3.3, 3Ј-H), 5.08 (1 H,
d, J1,2 1.9, 1-H), 5.13 (1 H, dd, J2Ј,3Ј 10.5, 2Ј-H), 5.21 (1 H, dd,
J2,3 3.5, 2-H), 5.32 (1 H, d, 4Ј-H) and 5.33 (1 H, dd, 3-H).
(2 H, dt, J 6.7, CH CH CH᎐), 3.10 (6 H, q, 3 × MeCH ),
4.41 (1 H, d, J1Ј,2Ј 7.0, 1Ј-H), 5.21 (1 H, br d, J1,P 6.6, 1-H)
᎐
2
2
2
2,3,4,6-Tetra-O-acetyl-ꢁ-D-galactopyranosyl-(1→4)-2,3-di-O-
acetyl-ꢀ-D-rhamnopyranosyl hydrogenphosphonate, triethyl-
ammonium salt 31
and 5.83 (1 H, ddt, JH,CH 6.7, JH,H-Z 10.1, JH,H-E 18.0, CH2-
2
CH᎐CH ); δ , δ and ESMS(Ϫ) data: see Table 1.
᎐
2
C
P
This compound was prepared by the reaction of the hemiacetal
30 (0.184 g, 0.32 mmol) with PCl3 (0.166 cm3, 1.91 mmol),
imidazole (0.433 g, 6.36 mmol) and Et3N (0.93 cm3, 6.7 mmol)
in acetonitrile (15 cm3) followed by hydrolysis as described for
the H-phosphonate 13. For work-up, the reaction mixture was
diluted with CH2Cl2 (100 cm3) and washed successively with
cold saturated aq. NaHCO3 (2 × 40 cm3) and cold 0.5 mol dmϪ3
aq. TEA hydrogen carbonate (2 × 40 cm3). The organic phase
was discarded. The aqueous washings were combined, and
extracted with CH2Cl2 (4 × 20 cm3). The combined organic
washings were dried by filtration through cotton wool, and
concentrated to produce the H-phosphonate 31 (0.165 g, 70%)
as a chromatographically homogeneous amorphous solid, [α]D25
ϩ23.1 (c 1.06, CHCl3); δH (200 MHz) 1.27 (3 H, d, J5,6 6.3,
6-H3), 1.30 (9 H, t, 3 × MeCH2), 1.94, 1.95, 2.00, 2.02, 2.08 and
2.11 (18 H, 6 × s, 6 × Ac), 3.03 (6 H, q, 3 × MeCH2), 3.56 (1 H,
t, J3,4 = J4,5 = 9.4, 4-H), 3.83 (1 H, t, J5Ј,6aЈ = J5Ј,6bЈ = 6.6, 5Ј-H),
3.98 (1 H, dq, 5-H), 3.99 (1 H, dd, 6Ј-Ha), 4.12 (1 H, dd, J6aЈ,6bЈ
11.0, 6Ј-Hb), 4.54 (1 H, d, J1Ј,2Ј 7.7, 1Ј-H), 4.94 (1 H, dd, J3Ј,4Ј 3.3,
3Ј-H), 5.10 (1 H, dd, J2Ј,3Ј 10.5, 2Ј-H), 5.21 (1 H, dd, J1,2 1.8,
2-H), 5.30 (1 H, d, 4Ј-H), 5.31 (1 H, dd, J2,3 3.6, 3-H), 5.44 (1 H,
dd, J1,P 8.8, 1-H) and 5.44 (1 H, d, JH,P 642.0, HP); δP Ϫ0.10;
ESMS(Ϫ): m/z 641.0 (100%, [M Ϫ Et3N Ϫ H]Ϫ) (expected m/z,
641.07. C30H50NO18P requires M, 743.27).
Methyl 2,3,4,6-tetra-O-acetyl-ꢁ-D-galactopyranosyl-(1→4)-2,3-
O-isopropylidene-ꢀ-D-rhamnopyranoside 28
A solution of acetobromogalactose 21 (1.49 g, 3.58 mmol) in
acetonitrile–toluene (10:3; 13 cm3) was added to a stirred mix-
ture of methyl 2,3-O-isopropylidene-α--rhamnopyranoside13
27 (0.318 g, 1.45 mmol), Hg(CN)2 (0.9 g, 3.58 mmol) and HgBr2
(0.64 g, 1.79 mmol) in the same mixed solvent (5 cm3). After
being stirred at rt for 16 h, the reaction mixture was diluted with
CH2Cl2 (50 cm3), washed successively with 1 mol dmϪ3 aq. KBr,
saturated aq. NaHCO3, and water, dried by filtration through
cotton wool, and concentrated. FCC [toluene–ethyl acetate,
(8:2)] of the residue gave the disaccharide derivative 28 (0.59 g,
74%), mp 126–129 ЊC (from ethanol); [α]D22 ϩ25.7 (c 1, CHCl3)
(Found: C, 52.5; H, 6.6. C24H36O14 requires C, 52.6; H, 6.6%);
δH (200 MHz) 1.23 (3 H, d, J5,6 6.3, 6-H3), 1.32 and 1.50 (6 H,
2 × s, CMe2), 2.00, 2.05, 2.07 and 2.15 (12 H, 4 × s, 4 × Ac),
3.34 (3 H, s, OMe), 3.36 (1 H, dd, J3,4 7.2, 4-H), 3.63 (1 H, dq,
J4,5 9.8, 5-H), 3.88 (1 H, t, J5Ј,6Ј 6.6, 5Ј-H), 4.06 (1 H, d, J2,3 5.7,
2-H), 4.14 (2 H, d, 6Ј-H2), 4.24 (1 H, dd, 3-H), 4.65 (1 H, d, J1Ј,2Ј
8.0, 1Ј-H), 4.81 (1 H, s, 1-H), 5.00 (1 H, dd, J3Ј,4Ј 3.2, 3Ј-H), 5.21
(1 H, dd, J2Ј,3Ј 10.3, 2Ј-H) and 5.36 (1 H, d, 4Ј-H).
2,3,4,6-Tetra-O-acetyl-ꢁ-D-galactopyranosyl-(1→4)-1,2,3-tri-
O-acetyl-ꢀ-D-rhamnopyranose 29
Dec-9-enyl 2,3,4,6-tetra-O-acetyl-ꢁ-D-galactopyranosyl-(1→4)-
2,3-di-O-acetyl-ꢀ-D-rhamnopyranosyl phosphate, triethyl-
ammonium salt 32
To a stirred solution of the disaccharide 28 (0.728 g) in chloro-
form (36 cm3) was added 90% aq. trifluoroacetic acid (4 cm3).
Stirring was continued for 2 h, whereafter the solution was
concentrated and toluene was twice evaporated off from the
residue. The residue was then dissolved in Ac2O (5 cm3) and a
sulfuric acid–acetic anhydride mixture [1:50 (v/v); 10.2 cm3]
was added. The solution was stirred at rt for 2 h, whereafter it
was diluted with CH2Cl2 (100 cm3), washed successively with
water, saturated aq. NaHCO3, and water, dried by filtration
through cotton wool, and concentrated. Toluene was twice
evaporated off from the residue. FCC (solvent B → solvent
C) of the residue gave the heptaacetate 29 (0.57 g, 69%), mp
145–148 ЊC (from ethanol); [α]D21 ϩ36.8 (c 0.99, CHCl3) (Found:
C, 50.6; H, 5.9. C26H36O17 requires C, 50.3; H, 5.9%); δH (200
MHz) 1.30 (3 H, d, J5,6 6.1, 6-H3), 1.96, 2.02, 2.03, 2.04 and 2.14
(15 H, 5 × s, 5 × Ac), 2.13 (6 H, s, 2 × Ac), 3.63 (1 H, t,
J3,4 = J4,5 = 9.4, 4-H), 3.82 (1 H, dq, 5-H), 3.87 (1 H, ddd, J5Ј,6aЈ
7.1, 5Ј-H), 4.02 (1 H, dd, J6aЈ,6bЈ 11.0, 6Ј-Ha), 4.16 (1 H, dd, J5Ј,6bЈ
6.4, 6Ј-Hb), 4.58 (1 H, d, J1Ј,2Ј 7.8, 1Ј-H), 4.97 (1 H, dd, J3Ј,4Ј 3.4,
3Ј-H), 5.14 (1 H, dd, J2Ј,3Ј 10.3, 2Ј-H), 5.19 (1 H, dd, J2,3 3.3,
2-H), 5.28 (1 H, dd, 3-H), 5.33 (1 H, dd, J4Ј,5Ј 0.5, 4Ј-H) and 5.94
(1 H, d, J1,2 1.9, 1-H).
This compound was prepared by condensation of the H-phos-
phonate 31 (0.14 g, 0.19 mmol) and dec-9-en-1-ol (0.067 cm3,
0.38 mmol) in pyridine (1 cm3) in the presence of trimethylacetyl
chloride (0.058 cm3, 0.47 mmol) followed by oxidation with
iodine (0.096 g, 0.376 mmol) in pyridine–water (95:5; 2 cm3) as
described for the synthesis of the phosphodiester 15. FCC
[CH2Cl2–MeOH–Et3N, (99:0:1) → (89:10:1)] gave the
phosphodiester 32 (0.148 g, 88%) as an amorphous solid, [α]D27
ϩ12.4 (c 1.09, CHCl3); δH (200 MHz) 1.18 (3 H, d, J5,6 6.0,
6-H3), 1.24 (9 H, t, 3 × MeCH2), 1.25 (10 H, m, 5 × CH2), 1.53
(2 H, tt, J 6.9, OCH2CH2CH2), 1.89, 1.90, 1.97, 1.98, 2.03 and
2.07 (18 H, 6 × s, 6 × Ac), 1.96 (2 H, dt, J 6.8, CH CH CH᎐),
᎐
2
2
3.00 (6 H, q, 3 × MeCH2), 3.51 (1 H, dd, J4,5 9.7, 4-H), 3.71–3.86
(4 H, m, 5Ј-H, 6Ј-Ha and OCH2CH2), 3.97 (1 H, dq, 5-H), 4.08
(1 H, dd, J5Ј,6bЈ 6.6, J6aЈ,6bЈ 11.2, 6Ј-Hb), 4.52 (1 H, d, J1Ј,2Ј 7.7,
2
3
1Ј-H), 4.84 (1 H, dd, JH,H 1.6, JH,H-Z 9.3, HCH᎐CH), 4.90
᎐
(1 H, dd, 3JH,H-E 17.0, HCH᎐CH), 4.92 (1 H, dd, 3Ј-H), 5.08 (1 H,
᎐
dd, J2Ј,3Ј 10.5, 2Ј-H), 5.19 (1 H, dd, J2,3 3.3, 2-H), 5.25 (1 H, d,
J3Ј,4Ј 4.0, 4Ј-H), 5.26 (1 H, dd, J3,4 9.4, 3-H), 5.34 (1 H, dd, J1,2
1.5, J1,P 8.8, 1-H) and 5.73 (1 H, ddt, JH,CH 6.8, CH CH᎐CH );
᎐
2
2
δP Ϫ3.12; ESMS(Ϫ): m/z 795.3 (100%,2 [M Ϫ Et3N Ϫ H]Ϫ)
(expected m/z, 795.21. C40H68NO19P requires M, 897.41).
2,3,4,6-Tetra-O-acetyl-ꢁ-D-galactopyranosyl-(1→4)-2,3-di-O-
acetyl-ꢀ-D-rhamnopyranose 30
Dec-9-enyl ꢁ-D-galactopyranosyl-(1→4)-ꢀ-D-rhamnopyranosyl
phosphate, ammonium salt 8
This compound was prepared from compound 29 (0.307 g) as
described for the hemiacetal derivative 12. Two consecutive
FCC separations [toluene–ethyl acetate, (55:45) → (8:2) and
solvent B → solvent D] gave the disaccharide α-hemiacetal 30
(0.19 g, 66%) as an amorphous solid, [α]D21 ϩ11 (c 0.97, CHCl3)
(Found: C, 49.4; H, 6.0. C24H34O16 requires C, 49.8; H, 5.9%);
δH (200 MHz) 1.28 (3 H, d, J5,6 6.2, 6-H3), 1.96, 2.01, 2.03, 2.04,
De-O-acetylation of compound 32 (74 mg) with 0.05 mol dmϪ3
NaOMe in methanol (3 h at rt) followed by work-up, as
described in the preparation of the phosphodiester 6, produced
a crude product, which then was applied to a column (18 × 1.5
Ϫ
cm) of Fractogel TSK DEAE-650 (S) (HCO3 -form) (Merck)
J. Chem. Soc., Perkin Trans. 1, 2001, 72–81
79

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eluted with a linear gradient of NH4HCO3 (0 → 0.1 mol
dmϪ3) in 3:2 water–propan-2-ol at 1 cm3 minϪ1 to afford the
phosphodiester 8 (41 mg, 88%) as an amorphous solid, [α]D26
ϩ22.4 (c 0.99, MeOH); δH (200 MHz; D2O) (inter alia) 1.22–
1.45 (13 H, m, 6-H3 and 5 × CH2), 1.63 (2 H, tt, J 6.9, OCH2-
2.6, 5-H), 4.45 (1 H, dd, J6a,6b 12.7, 6-Ha), 4.68 (1 H, dd, J5,6b 1.8,
6-Hb), 4.69 (1 H, J3,4 = J4,5 = 9.7, 4-H), 4.96 (1 H, d, J1Ј,2Ј 7.9,
1Ј-H), 5.39 (1 H, dd, J3Ј,4Ј 3.3, 3Ј-H), 5.48 (1 H, d, 4Ј-H), 5.70
(1 H, dd, J2Ј,3Ј 10.3, 2Ј-H), 5.85 (1 H, dd, J2,3 3.3, 2-H), 5.99 (1 H,
dd, 3-H), 6.48 (1 H, d, J1,2 1.7, 1-H) and 7.08–8.22 (35 H, m,
7 × Ph). Continued elution gave the α-linked disaccharide 40
(0.126 g, 13%) as an amorphous solid, [α]D23 ϩ124 (c 0.93, CHCl3)
(Found: C, 69.9; H, 5.1%); δH (200 MHz) 1.13 (3 H, d, J5Ј,6Ј 6.6,
6Ј-H3), 4.42–4.56 (2 H, m, 5- and 5Ј-H), 4.66 (1 H, dd, J5,6a 2.7,
J6a,6b 12.3, 6-Ha), 4.91 (1 H, J3,4 = J4,5 = 9.3, 4-H), 4.93 (1 H, dd,
J5,6b 0.5, 6-Hb), 5.67–5.94 (6 H, 1Ј-, 2-, 2Ј-, 3-, 3Ј- and 4Ј-H),
6.55 (1 H, d, J1,2 2.0, 1-H) and 7.05–8.28 (35 H, m, 7 × Ph).
CH CH ), 2.05 (2 H, dt, J 6.9, CH CH CH᎐), 4.48 (1 H, d, J
᎐
2
2
2
2
1Ј,2Ј
7.0, 1Ј-H), 5.32 (1 H, br d, J1,P 6.3, 1-H) and 5.91 (1 H, m,
CH CH᎐CH ); δ , δ and ESMS(Ϫ) data: see Table 1.
᎐
2
2
C
P
2,3,4-Tri-O-benzoyl-ꢀ,ꢁ-D-fucopyranose 34
To a solution of 1,2,3,4-tetra-O-benzoyl-α--fucopyranose 33
(0.5 g, 0.861 mmol) [prepared by standard benzoylation of α--
fucose with benzoyl chloride in pyridine–chloroform; δH (200
MHz) 1.34 (3 H, d, J5,6 6.4, 6-H3), 4.67 (1 H, q, 5-H), 5.92 (1 H,
d, 4-H), 6.01 (1 H, dd, J2,3 10.8, 2-H), 6.14 (1 H, dd, J3,4 3.0,
3-H), 6.91 (1 H, d, J1,2 3.3, 1-H) and 7.17–8.28 (20 H, m,
4 × Ph)] in acetonitrile (3 cm3) was added 2 mol dmϪ3 Me2NH
in THF (4.3 cm3; 8.61 mmol) and the mixture was kept at rt
with monitoring by TLC (solvents B and C). After 16–24 h, the
mixture was concentrated to dryness and acetonitrile was
evaporated off from the residue. FCC [toluene–ethyl acetate,
(99:1) → (85:15)] gave the unchanged starting material 33
(0.079 g, 16% recovery) and the hemiacetal 34 (0.25 g, 61%;
amorphous solid), [α]D22 ϩ247.4 (c 1, CHCl3) (Found: C, 68.3; H,
5.1. C27H24O8 requires C, 68.1; H, 5.1%); δH (200 MHz;
CDCl3 ϩ D2O) 1.26 (d, J5,6 6.4, 6-Hα), 1.35 (d, J5,6 6.3, 6-Hβ),
4.12 (dq, J4,5 0.8, 5-Hβ), 4.67 (q, H-5α), 5.06 (d, J1,2 6.8, 1-Hβ),
5.66–5.85 (m, 1-Hα, 2-H, 3-Hβ and 4-H), 6.09 (dd, J2,3 10.6, J3,4
3.2, 3-Hα) and 7.01–8.40 (15 H, m, 3 × Ph); α:β = 5:1.
2,3,4-Tri-O-benzoyl-ꢁ-D-fucopyranosyl-(1→4)-2,3,6-tri-O-
benzoyl-ꢀ-D-mannopyranose 38
This compound was prepared from compound 37 (0.307 g) as
described for the hemiacetal derivative 34. FCC [toluene →
solvent C] gave the disaccharide α-hemiacetal 38 (0.25 g, 90%)
as an amorphous solid, [α]D25 ϩ123.3 (c 1.06, CHCl3) (Found: C,
68.1; H, 5.0. C54H46O16 requires C, 68.2; H, 4.9%); δH (200
MHz) 0.83 (3 H, d, J5Ј,6Ј 6.2, 6Ј-H3), 3.53 (1 H, q, 5Ј-H), 4.07
(1 H, d, J1,OH 4.1, 1-OH), 4.33–4.46 (2 H, m, 5-H and 6-Ha),
4.58 (1 H, J3,4 = J4,5 = 9.6, 4-H), 4.77 (1 H, dd, J5,6b 0.6, J6a,6b
12.5, 6-Hb), 4.95 (1 H, d, J1Ј,2Ј 7.9, 1Ј-H), 5.35 (1 H, d, J1,2 1.8,
1-H), 5.42 (1 H, dd, J2Ј,3Ј 10.2, 3Ј-H), 5.46 (1 H, d, J3Ј,4Ј 3.2, 4Ј-
H), 5.62–5.75 (2 H, m, 2- and 2Ј-H), 5.95 (1 H, dd, J2,3 3.0, 3-H)
and 6.98–8.22 (30 H, m, 6 × Ph).
2,3,4-Tri-O-benzoyl-ꢁ-D-fucopyranosyl-(1→4)-2,3,6-tri-O-
benzoyl-ꢀ-D-mannopyranosyl hydrogenphosphonate, triethyl-
ammonium salt 39
2,3,4-Tri-O-benzoyl-ꢀ-D-fucopyranosyl trichloroacetimidate 35
To a stirred solution of the hemiacetal 34 (0.228 g, 0.48 mmol)
and CCl3CN (2 cm3, 20 mmol) in dichloromethane (4 cm3)
cooled to 0 ЊC was added DBU (0.072 cm3, 0.48 mmol) under
argon. The mixture was stirred for 2 h at 0 ЊC and then concen-
trated. FCC (solvent A) of the residue gave the α-fucopyranosyl
trichloroacetimidate 35 (0.277 g, 93%) as an amorphous solid,
[α]D22 ϩ209.4 (c 1, CHCl3); δH (200 MHz) 1.34 (3 H, d, J5,6 6.5,
6-H3), 4.66 (1 H, dq, 5-H), 5.89 (1 H, dd, J4,5 0.5, 4-H), 5.92
(1 H, dd, J2,3 10.5, 2-H), 6.06 (1 H, dd, J3,4 3.2, 3-H), 6.86 (1 H,
d, J1,2 3.3, 1-H), 7.10–8.23 (15 H, m, 3 × Ph) and 8.60 (1 H, s,
HN); δC 16.19 (C-6), 67.95 (C-5), 68.05 (C-2), 68.66 (C-3), 71.29
(C-4), 90.91 (CCl3), 94.11 (C-1), 128.30–133.48 (Ph), 160.78
(C=NH) and 165.62–165.83 (C=O); ESMS(ϩ): m/z 459.2
(100%, [M Ϫ CCl3CONH]ϩ) (expected m/z, 459.47. C29H24-
Cl3NO8 requires M, 620.86).
This compound was prepared from the hemiacetal 38 (0.208 g,
0.219 mmol) as described for the H-phosphonate derivative 13.
This produced the disaccharide hydrogenphosphonate 39
(0.232 g, 95%) as
a chromatographically homogeneous
amorphous solid, [α]D25 ϩ102.4 (c 0.96, CHCl3); δH (200 MHz)
0.81 (3 H, d, J5Ј,6Ј 6.3, 6Ј-H3), 1.27 (9 H, t, 3 × MeCH2), 3.01
(6 H, q, 3 × MeCH2), 3.49 (1 H, q, 5Ј-H), 4.37 (1 H, ddd, J5,6a
2.7, 5-H), 4.43 (1 H, dd, J6a,6b 12.9, 6-Ha), 4.53 (1 H,
J3,4 = J4,5 = 9.5, 4-H), 4.65 (1 H, dd, J5,6b 1.4, 6-Hb), 4.87 (1 H, d,
J1Ј,2Ј 7.9, 1Ј-H), 5.34 (1 H, dd, J3Ј,4Ј 3.4, 3Ј-H), 5.42 (1 H, d,
4Ј-H), 5.64 (1 H, dd, J2Ј,3Ј 10.4, 2Ј-H), 5.67 (1 H, dd, J1,2 2.0, 2-
H), 5.70 (1 H, dd, J1,P 7.7, 1-H), 5.88 (1 H, dd, J2,3 3.3, 3-H),
7.01 (1 H, d, JH,P 636.9, HP) and 7.05–8.15 (30 H, m, 6 × Ph);
δP 0.11; ESMS(Ϫ): m/z 1012.8 (100%, [M Ϫ Et3N Ϫ H]Ϫ)
(expected m/z, 1013.17. C60H62NO18P requires M, 1115.37).
2,3,4-Tri-O-benzoyl-ꢁ-D-fucopyranosyl-(1→4)-1,2,3,6-tetra-O-
benzoyl-ꢀ-D-mannopyranose 37 and 2,3,4-tri-O-benzoyl-ꢀ-D-
fucopyranosyl-(1→4)-1,2,3,6-tetra-O-benzoyl-ꢀ-D-manno-
pyranose 40
Dec-9-enyl 2,3,4-tri-O-benzoyl-ꢁ-D-fucopyranosyl-(1→4)-2,3,6-
tri-O-benzoyl-ꢀ-D-mannopyranosyl phosphate, triethyl-
ammonium salt 41
This compound was prepared by condensation of the H-phos-
phonate 39 (0.12 g, 0.107 mmol) and dec-9-en-1-ol (0.038 cm3,
0.215 mmol) in pyridine (1 cm3) in the presence of trimethyl-
acetyl chloride (0.033 cm3, 0.268 mmol) followed by oxidation
with iodine (0.055 g, 0.215 mmol) in pyridine–water (95:5; 2
cm3) as described for the synthesis of the phosphodiester 15.
FCC [CH2Cl2–MeOH–Et3N, (99:0:1) → (89:10:1)] gave the
phosphodiester 41 (0.108 g, 80%) as an amorphous solid, [α]D25
ϩ82.2 (c 1, CHCl3); δH (200 MHz) 0.84 (3 H, d, J5Ј,6Ј 6.3, 6Ј-H3),
1.24 (10 H, m, 5 × CH2), 1.30 (9 H, t, 3 × MeCH2), 1.58 (2 H, tt,
A mixture of the trichloroacetimidate 35 (0.554 g, 0.89 mmol),
1,2,3,6-tetra-O-benzoyl-α--mannopyranose3 36 (0.638 g, 1.07
mmol) and freshly activated molecular sieves 4 Å (powder, 1 g)
in dry dichloromethane (5 cm3) was stirred under argon for 30
min. TMS triflate (0.046 cm3, 0.22 mmol) was then added and
the mixture was cooled to Ϫ70 ЊC. Stirring was continued for
a further 1.5 h, while the mixture slowly warmed to Ϫ10 ЊC.
The reaction was quenched with a few drops of N,N-
diisopropylethylamine, the solids were filtered off, and the
solvent was removed under reduced pressure. FCC (toluene
→ solvent B) of the residue gave a mixture of the disacchar-
ides 37 and 40, which were then separated by further FCC
[dichloromethane–ethyl acetate, (100:0) → (98:2)]. That
provided, first, the β-linked disaccharide 37 (0.582 g, 62%) as an
amorphous solid, [α]D23 ϩ118 (c 1.03, CHCl3) (Found: C, 69.6; H,
4.7. C61H50O17 requires C, 69.4; H, 4.8%); δH (200 MHz) 0.82
(3 H, d, J5Ј,6Ј 6.3, 6Ј-H3), 3.56 (1 H, q, 5Ј-H), 4.27 (1 H, ddd, J5,6a
J 6.9, OCH CH ), 1.97 (2 H, dt, J 6.9, CH CH CH᎐), 3.05 (6 H,
᎐
2
2
2
2
q, 3 × MeCH2), 3.47 (1 H, q, 5Ј-H), 3.90 (2 H, m, OCH2CH2),
4.37–4.49 (2 H, m, 5-H and 6-Ha), 4.55 (1 H, J3,4 = J4,5 = 9.4,
4-H), 4.64 (1 H, dd, J5,6b 1.1, J6a,6b 11.7, 6-Hb), 4.87 (1 H, d, J1Ј,2Ј
2
3
7.8, 1Ј-H), 4.89 (1 H, dd, JH,H 1.3, JH,H-Z 10.4, HCH᎐CH),
᎐
4.95 (1 H, dd, 3JH,H-E 17.2, HCH᎐CH), 5.33 (1 H, dd, J2Ј,3Ј 10.4,
᎐
3Ј-H), 5.43 (1 H, d, J3Ј,4Ј 3.3, 4Ј-H), 5.65 (1 H, dd, J1,P 8.3, 1-H),
5.66 (1 H, dd, 2Ј-H), 5.74 (1 H, dd, J1,2 2.5, 2-H), 5.78 (1 H, ddt,
80
J. Chem. Soc., Perkin Trans. 1, 2001, 72–81

View Article Online
JH,CH 6.9, CH CH᎐CH ), 5.91 (1 H, dd, J2,3 3.4, 3-H) and 7.05–
(2 H, tt, J 6.9, OCH CH ), 1.99 (2 H, dt, J 6.9, CH CH CH᎐),
᎐
2 2 2 2
᎐
2
2
2
8.10 (30 H, m, 6 × Ph); δP Ϫ2.83; ESMS(Ϫ): m/z 1166.9
(100%, [M Ϫ Et3N Ϫ H]Ϫ) (expected m/z, 1167.31. C70H80NO19P
requires M, 1269.51).
3.10 (6 H, q, 3 × MeCH2), 4.00 (2 H, m, OCH2CH2), 4.44 (1 H,
q, 5Ј-H), 4.57–4.70 (2 H, m, 5-H and 6-Ha), 4.79 (1 H,
J3,4 = J4,5 = 9.8, 4-H), 4.89 (2 H, br d, 6-Hb and HCH᎐CH), 4.96
᎐
2
3
(1 H, dd, JH,H 1.9, JH,H-E 17.0, HCH᎐CH), 5.65–5.83 (8 H,
᎐
m, 1-, 1Ј-, 2-, 2Ј-, 3-, 3Ј-, 4Ј-H and CH CH᎐CH ) and 7.00–
᎐
2
2
Dec-9-enyl ꢁ-D-fucopyranosyl-(1→4)-ꢀ-D-mannopyranosyl
phosphate, triethylammonium salt 9
8.25 (30 H, m, 6 × Ph); δP Ϫ2.60; ESMS(Ϫ): m/z 1166.9
(100%, [M Ϫ Et3N Ϫ H]Ϫ) (expected m/z, 1167.31. C70H80NO19P
requires M, 1269.51).
De-O-benzoylation of compound 41 (101 mg) with 0.05 mol
dmϪ3 NaOMe in methanol (16 h at rt) followed by work-up, as
described in the preparation of the phosphodiester 7, gave the
phosphodiester 9 (51 mg, 99%) as an amorphous solid, [α]D28
ϩ22.5 (c 0.99, MeOH); δH (D2O) (inter alia) 1.22–1.39 (22 H, m,
6Ј-H3, 3 × MeCH2 and 5 × CH2), 1.58 (2 H, tt, J 6.9, OCH2-
Dec-9-enyl ꢀ-D-fucopyranosyl-(1→4)-ꢀ-D-mannopyranosyl
phosphate, triethylammonium salt 10
De-O-benzoylation of compound 44 (95 mg) with 0.05 mol
dmϪ3 NaOMe in methanol (16 h at rt) followed by work-up, as
described in the preparation of the phosphodiester 7, gave the
phosphodiester 10 (48 mg, 100%) as an amorphous solid, [α]D28
ϩ69.8 (c 0.98, MeOH); δH (200 MHz; D2O) (inter alia) 1.23 (3
H, d, J5Ј,6Ј 6.6, 6Ј-H3), 1.26-1.40 (19 H, m, 3 × MeCH2 and
5 × CH2), 1.61 (2 H, tt, J 6.5, OCH2CH2CH2), 2.04 (2 H, dt,
CH CH ), 2.01 (2 H, dt, J 6.9, CH CH CH᎐), 3.15 (6 H,
᎐
2
2
2
2
q, 3 × MeCH2), 4.38 (1 H, d, J1Ј,2Ј 7.6, 1Ј-H), 5.37 (1 H, br d,
J1,P 7.1, 1-H) and 5.83 (1 H, m, CH CH᎐CH ); δ , δ and
᎐
2
2
C
P
ESMS(Ϫ) data: see Table 1.
2,3,4-Tri-O-benzoyl-ꢀ-D-fucopyranosyl-(1→4)-2,3,6-tri-O-
benzoyl-ꢀ-D-mannopyranose 42
J 7.0, CH CH CH᎐), 3.20 (6 H, q, 3 × MeCH ), 5.20 (1 H, br s,
᎐
2
2
2
1Ј-H), 5.42 (1 H, br d, J1,P 7.6, 1-H) and 5.83 (1 H, m,
CH CH᎐CH ); δ , δ and ESMS(Ϫ) data: see Table 1.
This compound was prepared from compound 40 (160 mg) as
described for the hemiacetal derivative 34. FCC [toluene →
solvent C] gave the disaccharide α-hemiacetal 40 (99 mg, 69%)
as an amorphous solid, [α]D26 ϩ54.7 (c 1.02, CHCl3) (Found: C,
68.0; H, 5.0. C54H46O16 requires C, 68.2; H, 4.9%); δH (200
MHz) 1.13 (3 H, d, J5Ј,6Ј 6.4, 6Ј-H3), 3.83 (1 H, d, J1,OH 4.3,
1-OH), 4.52 (1 H, q, 5Ј-H), 4.60 (1 H, ddd, J5,6b 0.7, 5-H), 4.65
(1 H, dd, J5,6a 2.6, 6-Ha), 4.81 (1 H, J3,4 = J4,5 = 9.6, 4-H), 5.01
(1 H, dd, J6a,6b 11.2, 6-Hb), 5.40 (1 H, d, J1,2 1.8, 1-H), 5.68 (1 H,
dd, 2-H), 5.75 (1 H, dd, J2,3 3.4, 3-H), 5.76–5.85 (4 H, m, 1Ј-, 2Ј-,
3Ј- and 4Ј-H) and 7.10–8.25 (30 H, m, 6 × Ph).
᎐
2
2
C
P
Acknowledgements
This work and I. A. I. were supported by a Wellcome Trust
International Grant. The research of A. V. N. was supported by
an International Research Scholar’s award from the Howard
Hughes Medical Institute. One of us (A. J. R.) thanks the
BBSRC for the award of a studentship.
References
1 Part 10, A. Crossman, Jr., J. S. Brimacombe, M. A. J. Ferguson and
T. K. Smith, Carbohydr. Res., 1999, 321, 42.
2 M. J. McConville and M. A. J. Ferguson, Biochem. J., 1993, 294,
305.
2,3,4-Tri-O-benzoyl-ꢀ-D-fucopyranosyl-(1→4)-2,3,6-tri-O-
benzoyl-ꢀ-D-mannopyranosyl hydrogenphosphonate, triethyl-
ammonium salt 43
3 A. V. Nikolaev, T. J. Rutherford, M. A. J. Ferguson and J. S.
Brimacombe, J. Chem. Soc., Perkin Trans. 1, 1995, 1977.
4 A. V. Nikolaev, T. J. Rutherford, M. A. J. Ferguson and J. S.
Brimacombe, J. Chem. Soc., Perkin Trans. 1, 1996, 1559.
5 A. P. Higson, Y. E. Tsvetkov, M. A. J. Ferguson and A. V. Nikolaev,
J. Chem. Soc., Perkin Trans. 1, 1998, 2587.
6 A. P. Higson, Y. E. Tsvetkov, M. A. J. Ferguson and A. V. Nikolaev,
Tetrahedron Lett., 1999, 40, 9281.
7 G. M. Brown, A. R. Millar, C. Masterson, J. S. Brimacombe, A. V.
Nikolaev and M. A. J. Ferguson, Eur. J. Biochem., 1996, 242, 410.
8 I. A. Ivanova, A. J. Ross, M. A. J. Ferguson and A. V. Nikolaev,
J. Chem. Soc., Perkin Trans. 1, 1997, 969.
This compound was prepared from the hemiacetal 42 (88 mg,
0.092 mmol) as described for the H-phosphonate derivative 13.
This produced the disaccharide hydrogenphosphonate 43 (100
mg, 97%) as a chromatographically homogeneous amorphous
solid, [α]D21 ϩ61 (c 1.06, CHCl3); δH (200 MHz) 1.08 (3 H, d, J5Ј,6Ј
6.3, 6Ј-H3), 1.29 (9 H, t, 3 × MeCH2), 3.01 (6 H, q,
3 × MeCH2), 4.47 (1 H, q, 5Ј-H), 4.57–4.68 (2 H, m, 5-H and
6-Ha), 4.79 (1 H, J3,4 = J4,5 = 9.4, 4-H), 4.93 (1 H, dd, J5,6b 2.8,
J6a,6b 12.9, 6-Hb), 5.67 (1 H, dd, J1,2 2.0, J2,3 3.0, 2-H), 5.70–5.82
(6 H, m, 1-, 1Ј-, 2Ј-, 3-, 3Ј- and 4Ј-H), 7.10 (1 H, d, JH,P 640.4,
HP) and 6.92–8.23 (30 H, m, 6 × Ph); δP 0.57; ESMS(Ϫ): m/z
1013.0 (100%, [M Ϫ Et3N Ϫ H]Ϫ) (expected m/z, 1013.17.
C60H62NO18P requires M, 1115.37).
9 A. V. Nikolaev, I. A. Ivanova, V. N. Shibaev and N. K. Kochetkov,
Carbohydr. Res., 1990, 204, 65.
10 N. S. Utkina, A. V. Nikolaev and V. N. Shibaev, Sov. J. Bioorg.
Chem. (Engl. Transl.), 1991, 17, 303.
11 C. Copeland and R. V. Stick, Aust. J. Chem., 1978, 31, 1371.
12 S. A. Abbas and A. H. Haines, Carbohydr. Res., 1975, 39, 358.
13 T. Nishio, Y. Miyake, K. Kubota, M. Yamai, S. Miki, T. Ito and
T. Oku, Carbohydr. Res., 1996, 280, 357.
14 G. M. Bebault and G. G. S. Dutton, Can. J. Chem., 1972, 50, 3373.
15 A. Hasegawa, K. Adachi, M. Yoshida and M. Kiso, Carbohydr.
Res., 1992, 230, 273.
16 J. A. L. M. van Dorst, C. J. van Heusden, J. M. Tikkanen, J. P.
Kamerling and J. F. G. Vliegenthart, Carbohydr. Res., 1997, 297,
209.
17 K. Bock and K. Pedersen, Adv. Carbohydr. Chem. Biochem., 1983,
41, 27.
18 J. V. O’Conner, H. A. Nunez and R. Barker, Biochemistry, 1979, 18,
500.
19 F. H. Routier, A. P. Higson, I. A. Ivanova, A. J. Ross, Y. E. Tsvetkov,
D. V. Yashunsky, P. A. Bates, A. V. Nikolaev and M. A. J. Ferguson,
Biochemistry, 2000, 39, 8017.
Dec-9-enyl 2,3,4-tri-O-benzoyl-ꢀ-D-fucopyranosyl-(1→4)-2,3,6-
tri-O-benzoyl-ꢀ-D-mannopyranosyl phosphate, triethyl-
ammonium salt 44
This compound was prepared by condensation of the H-phos-
phonate 43 (100 mg, 0.09 mmol) and dec-9-en-1-ol (0.035 cm3,
0.197 mmol) in pyridine (1 cm3) in the presence of trimethyl-
acetyl chloride (0.03 cm3, 0.246 mmol) followed by oxidation
with iodine (50 mg, 0.197 mmol) in pyridine–water (95:5; 2
cm3) as described for the synthesis of the phosphodiester 15.
FCC [CH2Cl2–MeOH–Et3N, (99:0:1) → (87:12:1)] gave the
phosphodiester 44 (95 mg, 78%) as an amorphous solid, [α]D26
ϩ46 (c 0.99, CHCl3); δH (200 MHz) 1.04 (3 H, d, J5Ј,6Ј 6.3,
6Ј-H3), 1.23 (10 H, m, 5 × CH2), 1.31 (9 H, t, 3 × MeCH2), 1.64
J. Chem. Soc., Perkin Trans. 1, 2001, 72–81
81