Synthesis and characterisation of muramic acid 1',2-lactam-β-(14)-D-glucosamine derivatives related to repeating units of bacterial spore cortex

Article abstract of DOI:10.1016/S0008-6215(98)00248-1

A procedure for preparing allyl 4,6-O-benzylidene-N-phthaloyl-muramic acid methyl ester is described. Depending on the reaction conditions, a partial cleavage of the phthaloyl group and formation of the tricyclic allyl 4,6-O-benzylidene-muramic acid 1',2-

Full text of DOI:10.1016/S0008-6215(98)00248-1

Carbohydrate Research 313 (1998) 1±14
Synthesis and characterisation of muramic acid
10,2-lactam-ꢀ-(1!4)-d-glucosamine derivatives
related to repeating units of bacterial spore
cortex
Dina Keglevica,*, Biserka Kojic-Prodica,*, Zrinka Banic Tomisica, b
Anthony L. Spekc
,
a
-
Â
Ruder BosÏkovic Institute, P.O.B. 1016, HR-10000 Zagreb, Croatia
b
Â
Pliva - Research Institute, Prilaz baruna Filipovica 25, HR-10000 Zagreb, Croatia
c Department of Crystal and Structural Chemistry, Bijvoet Centre for Biomolecular Research, Utrecht
University, Padualaan 8, NL-3584 CH, Utrecht, The Netherlands
Received 18 May 1998; accepted 11 September 1998
Abstract
A procedure for preparing allyl 4,6-O-benzylidene-N-phthaloyl-muramic acid methyl ester is
described. Depending on the reaction conditions, a partial cleavage of the phthaloyl group and
formation of the tricyclic allyl 4,6-O-benzylidene-muramic acid 10,2-lactam also occurred; a suc-
cessful route to the latter was via de-esteri®cation (LiI) of the protected muramic acid ester group,
dephthaloylation and cyclisation. This compound was characterised by X-ray structure analysis.
Treatment of the protected muramic acid ester with tris(triphenylphosphine)rhodium(I) chloride
produced the desired hemiacetal which was then transformed into the trichloroacetimidate donor
and coupled with allyl 3,6-di-O-benzyl-2-deoxy-2-phthalimido-ꢀ-d-glucopyranoside to provide
allyl O-(4,6-O-benzylidene-2-deoxy-3-O-[(R)-1-(methoxycarbonyl)ethyl]-2-phthalimido-ꢀ-d-gluco-
pyranosyl)-(1!4)-3,6-di-O-benzyl-2-deoxy-2-phthalimido-ꢀ-d-glucopyranoside. De-esteri®cation
followed by removal of the two phthalimido groups and Ac2O/Py treatment gave allyl O-(2-
amino-4,6-O-benzylidene-3-O-[(R)-1-carboxyethyl]-2-deoxy-ꢀ-d-glucopyranosyl-10,2-lactam)-(1!4)-
2-acetamido-3,6-di-O-benzyl-2-deoxy-ꢀ-d-glucopyranoside. The conformation analysis of allyl
4,6-O-benzylidene-muramic acid ꢁ-lactam and propan-2-onyl glycoside of the protected muramic
ester revealed in solid state for both compounds a chair conformation of glucopyranose and 1,3-
dioxane rings with trans ring junction. The ꢁ-lactam ring of the tricyclic muramyl lactam exhibits a
conformation between sofa and half-chair. # 1998 Elsevier Science Ltd. All rights reserved.
Keywords: Muramic acid; muramic acid 10,2-lactam derivatives; Bacterial spore cortex repeating units; NMR
spectroscopy; X-ray structure; Conformational analysis
*Corresponding authors. Fax: +385-1-4680084; e-mail:
kojic@rudjer.irb.hr
0008-6215/98/$Ðsee front matter # 1998 Elsevier Science Ltd. All rights reserved
PII S0008-6215(98)00248-1

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D. Keglevic et al./Carbohydrate Research 313 (1998) 1±14
2
1. Introduction
the introduction of the lactic acid residue at the C-
3 of 1 is practically quantitative. During the reac-
tion, a partial phthalimido-ring-opening had also
occurred to give a mixture of 2-phthalimido- and
2-phthalamido-3-O-lactyl acid derivatives. Treat-
ment of the crude product with Dowex H+ resin
and Ac2O/Py converted the phthalamido acid sub-
stituent into the phthalimido ring without a€ecting
the lactyl acid group. Esteri®cation of the latter
with diazomethane a€orded pure 2 (73% calcd on
It has been widely recognised that the bacterial
spore peptidoglycan, so called spore cortex, has a
composition di€erent from that of the bacterial
vegetative cell [1]. In the spore cortex, a substantial
part of the muramic acid residues lack the peptide
and N-acetyl substituents and instead form an
intramolecularly cyclised ꢁ-lactam structure [2,3].
Although the process of spore formation has been
studied extensively in recent years by the molecular
genetic approach [4], information on the chemistry
of cortex and its fragments is still very scarce. We
have reported [5,6] previously the synthesis, X-ray
and conformational analysis of several muramic
acid ꢁ-lactams and their 4-O-(2-acetamido-2-
deoxy-ꢀ-d-glucopyranosyl)-substituted derivatives.
The aim of the present work was to prepare a
disaccharide structurally and sequentially related
to the cortex fragment, in which a muramic acid ꢁ-
lactam structure is ꢀ-glycosidically linked to the 4-
position of the GlcNAc moiety.
1
1). The H NMR data (ꢁ 5.33, J1,2 8.3 Hz) were
consistent with the ꢀ con®guration, and the large
J2,3, J3,4 and J4,5 values (8.7±10.4 Hz) indicated the
4C1 conformation of the pyranoid ring.
In an earlier experiment of this work two major
products were isolated: the phthalimido ester 2 and
the MurLactam derivative 3 (ꢀ 30 and ꢀ 20%,
respectively). In the latter case, apparently, the
open-ring phthalamido derivative has undergone
cleavage of the phthaloyl group to give an inter-
mediary amino ester which cyclised to 3. A char-
acteristic feature of the NMR spectra of muramic
acid 10,2-lactam series is an up®eld position of the
signals for H-2 and for C-2 [5]. Indeed, in the
spectra of 3 the H-2 signal at 3.42 ppm and the 13C
signal assigned to C-2 at 57.05 ppm were the most
up®eld resonances of the molecule. To con®rm the
tricyclic structure of 3 the X-ray crystallographic
analysis was performed. The structure determined
correlates to the spectroscopic data.
2. Results and discussion
Synthesis.ÐAttempts to convert a muramic acid
ꢁ-lactam derivative into an ecient glycosyl donor
were not successful. Alternatively, we prepared 1-
O-allyl-4,6-O-benzylidene-N-phthaloylmuramic acid
methyl ester (2) as a suitably protected inter-
mediate for glycosidation of the glucosamine unit.
As the starting compound for the synthesis of 2,
allyl 4,6-O-benzylidene-2-deoxy-2-phthalimido-ꢀ-
d-glucopyranoside (1) [7,8] was used. The phthali-
mido group was chosen for the protection of the
amino function because of its activating and ꢀ-
directing e€ects during glycosidation. It was found
that in 1,4-dioxane using six equivalents of NaH,
In order to obtain a higher yield of 3, dephtha-
loylation of 2 was investigated. The reaction of 2
with ethanolic hydrazine hydrate was not a clean
1
one; H NMR spectra indicated that both, the lac-
tyl methyl ester group and the allyl aglycon were
a€ected by the reagent. Treatment of 2 with hydra-
zine acetate which was found [9] to be compatible
with the methyl ester group resulted in cyclisation
into the lactam ring together with reduction of the
Scheme 1. Monosaccharide synthesis.

Â
D. Keglevic et al./Carbohydrate Research 313 (1998) 1±14
3
O-allyl double bond to give propyl MurLactam
derivative 5 (69%) and the starting 2 (15%).
Finally, 2 was de-esteri®ed by using LiI in pyridine
as the nucleophyle [10±12]; the liberated N-phta-
loylmuramic acid derivative 4 was then directly
treated with 1,2-diaminoethane [13] and Ac2O/Py
to give the desired lactam 3 (75%).
For the synthesis of the target disaccharide and
conversion of 2 into the glycosyl donor, the de-O-
allylation of 2 was required. Deprotection of 2 with
PdCl2 and CuCl [14] was accompanied by the
Wacker oxidation process [15±17] involving hydra-
tion of the allylic double bond followed by oxidation
to a methyl ketone. Thus, treatment of 2 a€orded the
reducing sugar 6 and the propan-2-onyl (acetonyl) ꢀ-
glycoside 7 (37 and 40%, respectively). They were
resolved by column chromatography; the structure
of 7 was con®rmed by X-ray structure analysis.
An ecient access to the reducing sugar 6 (73%)
was by the selective removal of the allyl group in 2
using tris(triphenylphosphine)rhodium (I) chloride
(Wilkinson catalyst) [18] and mercuric ion cata-
lysed hydrolysis [13].
Treatment of 10 with LiI, as described for 4 gave
the disaccharide acid 11 (77%) which was then
directly converted into the desired disaccharide 12
(76%) with 1,2-diaminoethane and Ac2O/Py. The
1H NMR spectra of 12 revealed the two anomeric
0
0
protons at ꢁ 4.96 (J1,2 7.9 Hz) and ꢁ 4.48 (J1 ,2
8.2 Hz); a high-®eld signal at ꢁ 3.26 (H-20) and one
acetyl signal at ꢁ 1.87 were consistent with the
given structure.
X-ray structure analysis of 3 and 7.ÐThe mole-
cular structures of 3 and 7 with atom numbering
are shown in Figs. 1 and 2, respectively. The
molecule 3 is shown in ball and stick presentation
[24] based on the isotropic re®nement (limited
number of re¯ections disabled an anisotropic
re®nement, see the Experimental section). It crys-
tallizes with two independent molecules (A and B)
in the asymmetric unit. The ORTEP drawing [25]
for 7 is prepared with thermal ellipsoids at a 30%
probability level. In both compounds d-enantio-
mers were selected according to the synthesis; the
con®guration at the anomeric C-1 in the crystal
proved to be ꢀ.
The hemiacetal 6 was transformed with tri-
chloroacetonitrile [19] and diazabicyclo [5.4.0]
undecene (DBU) as the base [20] into the tri-
chloroacetimidate 8 (82%). Coupling of 8 with the
allyl 3,6-di-O-benzyl-2-deoxy-2-phthalimido-ꢀ-d-
glucopyranoside 9 [8,21,22] was performed in two
ways. By using silver tri¯ate as the catalyst [23] the
disaccharide 10 (63% yield) was obtained along
with unchanged acceptor 9 (21%) and the hemi-
acetal 6 (13%) formed by decomposition of 8.
Alternatively, the presence of catalytic amounts of
silyl tri¯uoromethanesulphonate (0.3 equivalents)
furnished the disaccharide 10 (66%). The ꢀ-d-dis-
Values of bond lengths and angles of both con-
formers of 3 (A and B) and 7 were not signi®cantly
di€erent (ꢁ 3ꢂ).
The molecular conformations of 3 and 7 are
described by selected torsion angles (Table 1),
Cremer±Pople [26] and asymmetry parameters [27]
[28] (Table 2). In both conformers of 3 and 7 glu-
4
copyranose moieties adopt usual chair C1 con-
formation (i.e. OC3 [29]). 1,3-Dioxane rings also
7
6
adopt chair C5 i.e. CO4 conformation (Table 2).
ꢁ-lactam rings in both conformers of 3 adopt
intermediate conformation between sofa E3 and
O
half-chair H3; displacements from four-atom (C-
1
accharide structure of 10 was con®rmed by its H
2,N-2,C-33,C-31) best least-squares planes are for
O-3, 0.16 A (A), 0.26 A (B) and for C-3, 0.53 A
(A), 0.50 A (B). Ring junctions between glucopyr-
anose and ꢁ-lactam ring in 3 (molecules A and B)
and between glucopyranose and 1,3-dioxane ring
[both in 3 (molecules A and B) and in 7] are trans.
NMR spectra which showed two doublets for
anomeric protons at 5.47 and 5.02 ppm with J 8.71
and J 8.18 Hz and were assigned to the two gluco-
pyranosyl residues of MurNPhth and GlcNPhth
moiety, respectively.
Scheme 2. Disaccharide synthesis.

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D. Keglevic et al./Carbohydrate Research 313 (1998) 1±14
4
Fig. 1. Molecular structure of 3A (ball and stick presentation [24]) with atom numbering.
Fig. 2. Molecular structure of 7 (ORTEP drawing [25]) with atom numbering. The thermal ellipsoids are drawn at a 35%
probability level.

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D. Keglevic et al./Carbohydrate Research 313 (1998) 1±14
5
Table 1
Selected torsion angles (ꢂ) for 3 (molecules A and B) and 7
Allyl 4,6-O-benzylidene-2-deoxy-3-O-[(R)-1-
(methoxycarbonyl)ethyl]-2-phthalimido-b-d-gluco-
pyranoside (2).ÐTo a solution of 1 (656 mg,
1.5 mmol) in dry 1,4-dioxane (8 mL) was added in
portions NaH (50% in oil, 435 mg, 9 mmol), and
the mixture was stirred under N2 for 30 min at
3
7
A
B
Glucopyranose ring
O-5±C-1±C-2±C-3
C-1±C-2±C-3±C-4
C-2±C-3±C-4±C-5
C-3±C-4±C-5±O-5
C-4±C-5±O-5±C-1
C-5±O-5±C-1±C-2
52(2)
56(2)
59(3)
65(3)
63(2)
54(2)
67(3)
61(2)
62(3)
65(3)
62(2)
64(3)
52(1)
53(1)
59(1)
65(1)
65(1)
58(1)
ꢂ
room temperature and for furtꢂher 3 h at 85 C. To
the suspension cooled to 70 C was then added
over 1 h a solution of (S)-2-chloropropionic acid
(310 mg, 2.8 mmol) in 1,4-dioxane (4 mL) and stir-
ring at this temperature was continued for 18 h.
Upon cooling, the mixture was diluted with dry
THF (30 mL) and Dowex (H+) resin was added
ꢁ-Lactam ring
N-2±C-2±C-3±O-3
C-2±C-3±O-3±C-31
C-3±O-3±C-31±C-33
O-3±C-31±C-33±N-2
C-31±C-33±N-2±C-2
C-33±N-2±C-2±C-3
58(2)
64(2)
42(3)
15(4)
9(3)
58(2)
71(3)
51(3)
22(3)
15(3)
31(3)
ꢂ
under stirring at ꢀ 4 C until all of the solid dis-
appeared and a clear solution (pH ꢀ4) was formed.
The resin was removed by ®ltration, washed with
THF, and the combined ®ltrate was concentrated
and co-concentrated with toluene. The remaining
white solid was treated at 0 ꢂC with pyridine (5 mL)
and Ac2O (5 mL), the solution was left at room
temperature for 24 h and then co-concentrated
with toluene. The remaining material was extracted
with chloroform (4Â20 mL), the extracts were
concentrated, and a solution of the resiꢂdue in 1:1
CHCl3±MeOH (4 mL) was treated at 0 C with an
ethereal diazomethane solution. After standing
overnight in a refrigerator, excess of diazomethane
was destroyed with a few drops of AcOH, and the
solution was concentrated. Column chromato-
graphy (19:1 benzene±EtOAc) of the residue a€or-
ded 2, isolated as a colourless syrup (573 mg, 73%),
[ꢃ]d +20ꢂ (c 1.2); Rf 0.45 (19:1 benzene±EtOAc),
31(3)
1,3-Dioxane ring
C-4±O-4±C-7±O-6
O-4±C-7±O-6±C-6
C-7±O-6±C-6±C-5
O-6±C-6±C-5±C-4
C-6±C-5±C-4±O-4
C-5±C-4±O-4±C-7
70(3)
69(3)
59(3)
53(3)
50(3)
60(2)
61(3)
64(3)
57(3)
59(3)
62(3)
56(2)
61(1)
65(1)
62(1)
55(1)
56(1)
58(1)
Crystal packing of 3 and 7.ÐIn the crystal struc-
ture of 3 an amide lactam nitrogen acts as a donor
to two oxygen atoms O-3 and O-4 from molecules
A and B forming a three-centre hydrogen bond
[30,31] (Fig. 3 and Table 3). The basic motif
includes two A and two B molecules (a sequence
. . .ABAB. . .) connected into a spiral along b. The
crystal packing of 7 is realized via van der Waals
interactions, only.
1
0.65 (5:1 toluene±EtOAc); H NMR (CDCl3): ꢁ
7.89±7.75 (m, 4 H, Phth), 7.48±7.37 (m, 5 H, Ph),
5.77±5.64 (m, 1 H, CH2CH ˆ CH2), 5.59 (s, 1 H,
PhCH), 5.33 (d, 1 H, J1,2 8.3 Hz, H-1), 5.14 and
5.04 (2 m, each 1 H, CH2CH ˆ CH2), 4.43 (dd, 1
H, J3,4 8.7 Hz, H-3), 4.40 (dd, 1 H, J6a,6b 10.2 Hz,
H-6a), 4.40 (q, JCH,Me 6.8 Hz, ꢃ-CH Lact), 4.29
(dd, 1 H, J2,3 10.4 Hz, H-2), 4.27 and 4.03 (2 m,
each 1 H, CH2CH ˆ CH2), 3.85 (t, 1 H, J6b,5 J6b,6a
10.2 Hz, H6-b), 3.76 (t, 1 H, J4,5 9.4 Hz, H-4), 3.66±
3.58 (m, 1 H, J5,6a 4.9 Hz, H-5), 3.23 (s, 3 H, CO2Me
Lact), 1.28 (d, 3 H, JMe,CH 6.8 Hz, Me Lact). 13C
NMR (CDCl3): ꢁ 173.3 (CO Lact; 167.8 (CO Phth);
137.1±123.5 (aromatic C and CH2CH ˆ CH2);
117.5 (CH2CH ˆ CH2); 101.2 (PhCH); 97.9 (C-1);
83.1 (C-4); 75.5, 74.1, 70.0, 68.6, 65.6 (C-3, 5, 6, ꢃ-
CH Lact and CH2CH ˆ CH2); 55.3 (C-2); 51.3
(CO2Me Lact); 18.7 (MeCH Lact). Anal. Calcd for
C28H29NO9: C, 64.24; H, 5.58; N, 2.67. Found: C,
64.54; H, 5.73; N, 2.95.
3. Experimental
General methods.ÐMelting points are uncor-
rected. Column chromatography was performed
on silica gel (Merck 0.040±0.063 mm) and TLC
on Silica Gel 60 with detection by charring with
10% H2SO4, chlorine±iodine reagent, or nin-
hydrin, if not stated otherwise. Optical rotations
were determined with an Optical Activity LTD
automatic AA-10 Polarimeter for solutions in
CHCl3. NMR spectra were recorded with a Varian
Gemini 300 spectrometer operating at 300 MHz
for 1H and 75 MHz for 13C for solutions in
CDCl3 (internal Me4Si). Double resonance experi-
ments were performed in order to assist in signal
assignment.

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D. Keglevic et al./Carbohydrate Research 313 (1998) 1±14
6
Table 2
Ring conformation analysisa for 3 (molecules A and B) and 7
Glucopyranose ring
Comp.
Asymmetry parameter (ꢂ)
w < jt:a:j > (ꢂ) Q(A) Â (ꢂ) È (ꢂ) Conform.
3A
ÁCsꢃC 1† ˆ ÁCsꢃC4† ˆ 5ꢃ2†
ÁCsꢃC 2† ˆ ÁCsꢃC5† ˆ 4ꢃ2†
ÁCsꢃC 3† ˆ ÁCsꢃO5† ˆ 9ꢃ2†
57.3(9)
0.58(2) 7(3) 281(21) OC3=4C1
ÁC2ꢃC
ÁC2ꢃC
ÁC2ꢃC
1
2
3
C
C
C
2† ˆ ÁC2ꢃC
3† ˆ ÁC2ꢃC
4† ˆ ÁC2ꢃO
4
5
5
C
O
C
5† ˆ 3ꢃ2†
5† ˆ 9ꢃ3†
1† ˆ 10ꢃ2†
4
3B
ÁCsꢃC 1† ˆ ÁCsꢃC 4† ˆ 3ꢃ2†
ÁCsꢃC 2† ˆ ÁCsꢃC 5† ˆ 4ꢃ2†
ÁCsꢃC 3† ˆ ÁCsꢃO 5† ˆ 2ꢃ2†
63(1)
0.65(3) 4(2) 143(29) OC3 ˆ C1
ÁC2ꢃC
ÁC2ꢃC
ÁC2ꢃC
1
2
3
C
C
C
2† ˆ ÁC2ꢃC
3† ˆ ÁC2ꢃC
4† ˆ ÁC2ꢃO
4
5
5
C
O
C
5† ˆ 2ꢃ3†
5† ˆ 4ꢃ3†
1† ˆ 5ꢃ3†
4
7
ÁCsꢃC 1 † ˆ ÁCsꢃC 4† ˆ 9ꢃ1†
ÁCsꢃC 2† ˆ ÁCsꢃC 5† ˆ 1ꢃ1†
ÁCsꢃC 3† ˆ ÁCsꢃO 5† ˆ 9ꢃ1†
59.1(5)
0.60(1) 8(1) 269(8) OC3 ˆ C1
ÁC2ꢃC
ÁC2ꢃC
ÁC2ꢃC
1
2
3
C
C
C
2† ˆ ÁC2ꢃC
3† ˆ ÁC2ꢃC
4† ˆ ÁC2ꢃO
4
5
5
C
O
C
5† ˆ 6ꢃ1†
5† ˆ 7ꢃ1†
1† ˆ 13ꢃ1†
ꢁ-lactam ring
Comp.
Asymmetry parameter (ꢂ)
whjt:a:ji (ꢂ)
Q(A) Â (ꢂ) È (ꢂ) Conform.
ÁCsꢃC 3† (ꢂ)
ÁC2ꢃC
3
O
3†(ꢂ)
ˆ ÁCsꢃC 33†(ꢂ)
ˆ ÁC2ꢃN
2
C
33† (ꢂ)
O
3A
3B
3A
8(2)
16(3)
45(1)
44(1)
60(1)
0.474(2) 42(3) 50(4)
0.52(3) 40(3) 45(5)
E3! H3
14(2)
8(3)
OH3/E3
6
7
ÁCsꢃO 4† ˆ ÁCsꢃC 6† ˆ 9ꢃ2†
0.61(3) 11(3) 295(15) CO4 ˆ C5
ÁCsꢃC 4† ˆ ÁCsꢃO 6† ˆ 13ꢃ2†
ÁCsꢃC 5† ˆ ÁCsꢃC 7† ˆ 2ꢃ2†
ÁC2ꢃO
ÁC2ꢃC
ÁC2ꢃC
4
4
5
C
C
C
4† ˆ ÁC2ꢃC
5† ˆ ÁC2ꢃO
6† ˆ ÁC2ꢃC
6
6
7
O
C
O
6† ˆ 18ꢃ3†
7† ˆ 9ꢃ3†
4† ˆ 9ꢃ3†
6
3B
ÁCsꢃO 4† ˆ ÁCsꢃC 6† ˆ 3ꢃ2†
ÁCsꢃC 4† ˆ ÁCsꢃO 6† ˆ 5ꢃ2†
ÁCsꢃC 5† ˆ ÁCsꢃC 7† ˆ 3ꢃ2†
59(1)
0.58(3) 0(3) 120(45) CO4=7C5
ÁC2ꢃO
ÁC2ꢃC
ÁC2ꢃC
4
4
5
C
C
C
4† ˆ ÁC2ꢃC
5† ˆ ÁC2ꢃO
6† ˆ ÁC2ꢃC
6
6
7
O
C
O
6† ˆ 4ꢃ3†
7† ˆ 4ꢃ3†
4† ˆ 7ꢃ3†
6
7
ÁCsꢃO 4† ˆ ÁCsꢃC 6† ˆ 7ꢃ1†
ÁCsꢃC 4† ˆ ÁCsꢃO 6† ˆ 4ꢃ1†
ÁCsꢃC 5† ˆ ÁCsꢃC 7† ˆ 3ꢃ1†
59.6(5)
0.59(1) 2(1) 251(30) CO4=7C5
ÁC2ꢃO
ÁC2ꢃC
ÁC2ꢃC
4
4
5
C
C
C
4† ˆ ÁC2ꢃC
5† ˆ ÁC2ꢃO
6† ˆ ÁC2ꢃC
6
6
7
O
C
O
6† ˆ 8ꢃ1†
7† ˆ 2ꢃ1†
4† ˆ 6ꢃ1†
aw < jt:a:j > is weighted average of ring torsion angles absolute values: Q, Â and È are Cremer±Pople parameters for atom
sequences: O-5±C-1±C-2±C-3±C-4±C-5 (glucopyranose ring), O-3±C-3±C-2±N-2±C-33±C-31 (ꢁ-lactam ring) and O-4±C-4±C-5±C-6±
O-6±C-7 (1,3-dioxane ring); calculated by PLATON [24].
Allyl 2-amino-4,6-O-benzylidene-3-O-[(R)-1-carbo-
xyethyl]-2-deoxy-b-d-glucopyranoside 10,2-lactam
(1-O-allyl-4,6-O-benzylidene-muramic acid 10,2-
lactam) (3).Ð(a) The reaction of 1 (437 mg,
1 mmol) with (S)-2-chloropropionic acid (206 mg,
1.9 mmol) was performed as described above. After
treatment with Dowex (H+) resin and concentration
of the ®ltrate, the residue was eluted from a col-
umn of silica gel with 20:2:1 CHCl3±MeOH±
AcOH. Fractions containing H2SO4 and peptide
positive components (Rf&0.8±0.4) were combined,
concentrated and treated with diazomethane as
described above. TLC (19:1 benzene±EtOAc, and
2:1 toluene±EtOAc) of the crude product showed

Â
D. Keglevic et al./Carbohydrate Research 313 (1998) 1±14
7
Fig. 3. Crystal packing of 3.
Table 3
Hydrogen bond geometry in the crystal packing of 3
DÁ Á ÁA (A)
D-H (A)
HÁ Á ÁA (A)
D-HÁ Á ÁA (ꢂ)
Symmetry operation on A
N-2A±HÁ Á ÁO-3B
N-2A±HÁ Á ÁO-4B
N-2B±HÁ Á ÁO-3A
N-2B±HÁ Á ÁO-4A
3.03(3)
3.33(3)
3.09(3)
3.24(2)
1.01(2)
1.01(2)
1.01(2)
1.01(2)
2.14(2)
2.54(2)
2.20(2)
2.49(2)
147(1)
136(1)
147(1)
131(1)
x 1, y, z
x 1, y, z
x+1, y+1/2 1, z+1
x+1, y+1/2 1, z+1
Two molecules in the asymmetric unit: A and B.
two major components (Rf 0.5 and 0.05, and 0.8
and 0.4, respectively). Column chromatography in
5:1 toluene±EtOAc a€orded the methyl ester 2
(168 mg, 32%) as a syrup; further elution with pure
EtOAc yielded the lactam 3 (90 mg, 25%) as a
white solid which was crystallised from EtOAc±
light petroleum, mp 186±188ꢂ (softening at 183 ꢂC),
(b) A solution of 2 (200 mg, 0.38 mmol) in dry
pyridine (6 mL) containing granulated 4 A mole-
cular sieves (0.4 g) was stirred for 1 h at room tem-
perature under N2. Anhydrous LiI (820 mg,
6.1 mmol) was added and the mixture was stirred
ꢂ
at 105 C for 24 h under N2. TLC (9:1 CHCl3±
MeOH), detection: Ce(SO4)2 showed a complete
conversion of 2 (Rf 0.9) into a new product (Rf
0.35). After cooling, the mixture was co-con-
centrated with toluene (3Â), the residue was taken
in CHCl3±water (2:1, 40 mL), and the aqueous
layer was acidi®ed with 2.5 M HCl to pH 3. The
product was extracted with CHCl3 (4Â), the com-
bined extracts washed with water, dried (Na2SO4)
and concentrated. Column chromatography (9:1
CHCl3±MeOH) of the residue a€orded the acid 4
as a syrup (149 mg, 77%) that was used directly in
the next step; 1H NMR (CDCl3) ꢁ 7.8±7.5 (m, 4 H,
Phth), 7.5±7.3 (m, 5 H, Ph), 5.76±5.63 (m, 1 H,
CH2CH ˆ CH2), 5.60 (s, 1 H, PhCH), 5.36 (d, 1 H,
J1,2 8.2 Hz, H-1), 5.16±5.03 (m, 2 H, CH2CH ˆ
CH2), 4.42 (dd, J6a,5 5.1, J6a,6b 10.3 Hz, H-6a) 4.41
(dd, J3,4 8.6 Hz, H-3), 4.32 (q, JCH,Me 6.9 Hz, ꢃ-CH
Lact), 4.29 (dd, J2,3 9.8 Hz, H-2), 4.27 and 4.05 (2
m, each 1 H, CH2CH ˆ CH2), 3.85 (t, 1 H, J6b,5
J6b,6a 10.25 Hz, H-6b), 3.77 (t, 1 H, J4,3 8.7, J4,5
ꢂ
1
[ꢃ]d 49 (c 0.9); H NMR (CDCl3): ꢁ 7.50±7.36
(m, 5 H, Ph), 6.07 (bs, 1 H, disappeared on H±D
exchange, NH), 5.95±5.84 (m, 1 H, CH2CH ˆ CH2),
5.58 (s, 1 H, PhCH), 5.35±5.26 (m, 2 H, CH2CH ˆ
CH2), 4.48 (d, 1H, J1,2 8.2 Hz, H-1), 4.39 and 4.10 (2
m, each 1 H, CH2CH ˆ CH2), 4.36 (dd, 1H, J6a,6b
10.5 Hz, H-6a), 4.31 (q, 1 H, JCH,Me 6.8 Hz, ꢃ-CH
Lact), 3.87 (t, 1 H, J6b,5 10.3 Hz, H6-b), 3.82 (t, 1
H, J4,5 9.0 Hz, H-4), 3.77 (t, 1 H, J3,4 9.1 Hz, H-3),
3.59±3.51 (m, 1 H, J5,6a 4.9 Hz, H-5), 3.42 (t, 1 H,
J2,3 8.9 Hz, H-2), 1.51 (d, 3 H, JMe,CH 6.8 Hz, Me
Lact). 13C NMR (CDCl3): ꢁ 171.0 (CO Lactam);
136.6, 129.2, 128.2, 126.2 (aromatic C); 132.6
(CH2CH ˆ CH2); 118.8 (CH2CH ˆ CH2); 101.9
(PhCH); 99.8 (C-1); 78.2 (C-4); 75.0, 74.6, 70.4,
68.4, 67.9 (C-3, 5, 6, ꢃ-CH Lact and CH2
CH ˆ CH2); 57.05 (C-2); 17.40 (MeCH Lact).
Anal. Calcd for C19H23NO6: C, 63.15; H, 6.41; N,
3.87. Found: C, 63.22; H, 6.52; N, 3.80.

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D. Keglevic et al./Carbohydrate Research 313 (1998) 1±14
8
9.5 Hz, H-4), 3.69±3.60 (m, 1H, H-5), 1.21 (d, 3H,
JMe,CH 6.8 Hz, Me Lact).
acetone (5 mL) containing mercuric oxide (2 mg,
0.009 mmol) and to this mercuric chloride (515 mg,
1.9 mmol) was added in 9:1 acetone-H2O (10 mL)
and the mixture was stirred for 2 h at room tem-
perature. Following solvent evaporation, the resi-
due was extracted with CHCl3 and the combined
extracts were washed with 30% aq KI followed by
water and dried (Na2SO4). Evaporation left a
syrup which was puri®ed by column chromato-
graphy with 10:1 benzene±acetone to give 6
(136 mg, 74%) as a shiny foam. Crystallisation
from EtOAc±petroleum ether a€orded crystals mp
170±172 ꢂC, [ꢃ]d +31ꢂ (c 1), 1H NMR (CDCl3 and
CDCl3±D2O): ꢁ 7.89±7.73 (m, 4 H, Phth), 7.47±
7.37 (m, 5 H, Ph), 5.60 (s, 1 H, PhCH), 5.53 (t, 1 H,
J1,2ꢀJ1,OH 8.4 Hz; changes to doublet on H±D
exchange, H-1), 4.50 (dd, 1 H, J3,4 8.6 Hz, H-3),
4.40 (dd, 1 H, J6a,6b 10.1 Hz, H-6a), 4.40 (q, 1H,
JCH,Me 6.8 Hz, ꢃ-CH Lact), 4.19 (dd, 1 H, J2,3
10.1 Hz, H-2), 3.83 (t, J6b,5 10.1 Hz, H-6b), 3.77 (t,
1 H, J4,5 9.3 Hz, H-4), 3.72±3.64 (m, 1 H, J5,6a
4.7 Hz, H-5), 3.24 (s, 3 H, CO2Me Lact), 1.29 (d, 3
H, JMe,CH 6.8 Hz, Me Lact). Anal. Calcd for
C25H25NO9: C, 62.10; H, 5.21; N, 2.90. Found: C,
62.25; H, 5.30, N, 3.0.
A solution of 4 (130 mg, 0.25 mmol) in n-butanol
(14 mL) was treated with 1,2-diaminoethane (1 mL,
15 mmol) for 20 h at 90 ꢂC under N2. After cooling
and co-concentration with toluene (4Â), the resi-
ꢂ
due was treated at 4 C with 1:1 Ac2O±pyridine
(5 mL), and the solution was left overnight at room
temperature. Concentration and co-distillation
with toluene left a solid that was extracted with 1:1
toluene±EtOAc (4Â10 mL). The extracts were con-
centrated, and the residue was fractionated on a
silica gel column with 1:1 toluene±EtOAc to give
the lactam 3 (69 mg, 75%) as a crystalline solid
which physical and NMR data were indistinguish-
able from those of 3 obtained under (a).
Propyl 2-amino-4,6-O-benzylidene-3-O-[(R)-1-
carboxyethyl]-2-deoxy-b-d-glucopyranoside 10,2-
lactam (5).ÐA solution of 2 (94 mg, 0.18 mmol)
and hydrazine acetate (714 mg, 7.8 mmol) in dry
MeOH (20 mL) was re¯uxed under stirring for
36 h. The solution was concentrated, the residue
partioned between water and CHCl3, the organic
layer was washed with water, dried and con-
centrated. Column chromatography (3:2 toluene±
EtOAc) of the residue gave, ®rst, the unreacted 2
(Rf 0.8, 14 mg, 15%) and then the propyl lactam 5
(Rf 0.25, 45 mg, 69%). Crystallisation of 5 from
1:10 EtOAc±light petroleum gave material with mp
Procedure (b) (with PdCl2-CuCl). To a solution
of 2 (143 mg, 0.27 mmol) was added PdCl2 (50 mg,
0.28 mmol) and CuCl (28 mg, 0.28 mmol), and
through the stirred suspension oxygen was bubbled
at room temperature for 4 h.; TLC (1:1 ethyl acet-
ate±petroleum ether) then showed complete dis-
appearance of the starting material (Rf 0.8) and the
presence of two overlapping spots (Rf ꢀ0.3). The
mixture was diluted with 1:1 ether±EtOAc, ®ltered
through Celite, and the ®ltrate concentrated to a
residue which was extracted with chloroform. The
combined extracts were washed with water, dried
(Na2SO4) and concentrated. Column chromato-
graphy (10:1 benzene±acetone) of the residue sepa-
rated the majority of the two products.
Crystallisation of the slower moving product from
EtOAc±petroleum ether a€orded 6 (49 mg, 37%)
which mp, [ꢃ]d and NMR data were indistinguish-
able from those of 6 obtained under procedure (a).
Found: C, 62.19; H, 5.31; N, 2.65. Crystallisation
of the faster moving product (EtOAc±petroleum
ether) gave propan-2-onyl 4,6-O-benzylidene-2-
deoxy-3-O-[(R)-1-(methoxycarbonyl)ethyl]-2-phth-
alimido-ꢀ-d-glucopyranoside (7) (59 mg, 40%); mp
ꢂ
1
172±174 C, [ꢃ]d 45ꢂ (c 1), H NMR (CDCl3): ꢁ
7.5±7.3 (m, 5 H, Ph), 6.02 (bs, 1 H, NH), 5.58 (s, 1
H, PhCH), 4.43 (d, J1,2 8.14 Hz, H-1), 4.35 (dd,
J6a,5 5.0, J6a,6b 10.3 Hz, H-6a), 4.31 (q, JCH,Me
6.7 Hz, ꢃ-CH Lact), 3.87 (t, J6b,5 10.3 Hz, H-6b),
3.85 (t, J4,3 9.2 Hz, H-4), 3.84±3.65 (m, 1H, 1/2
OCH2CH2CH3), 3.77 (t, J3,2 9.5 Hz, H-3), 3.59±
3.51 (m, 1H, J5,4 9.9 Hz, H-5) 3.51±3.44 (m, 1H, 1/
2 OCH2CH2CH3), 3.39 (t, 1 H, H-2), 1.70±1.59 (m,
2 H, OCH2CH2CH3), 1.51 (d, 3 H, JMe,CH 6.7 Hz,
Me Lact), 0.95 (t, 3 H, J 7.4 Hz, OCH2CH2CH3).
Anal. Calcd for C19H25NO6: C, 62.80; H, 6.93; N,
3.85. Found: C, 63.00; H, 7.19; N, 4.02.
4,6-O-Benzylidene-2-deoxy-3-O-[(R)-1-(meth-
oxycarbonyl)ethyl]-2-phthalimido-b-d-glucopyr-
anose (6).ÐProcedure (a) (with Wilkinson cata-
lyst): A solution of 2 (200 mg, 0.38 mmol), tris-
(triphenylphosphine)rhodium (I) chloride (92.5 mg,
0.1 mmol) and 1,8-diazabicyclo [2.2.2] octane
(Dabco, 18 mg, 0.16 mmol) in 10:5:1.25 ethanol±
benzene±water (16.5 mL) was re¯uxed for 30 h
(monitoring by TLC in 19:1 benzene±EtOAc). The
solvent was removed, the residue was dissolved in
ꢂ
1
146±147 C; [ꢃ]d 1ꢂ (c 1.5); H NMR (CDCl3): ꢁ
7.90±7.74 (m, 4 H, Phth), 7.47±7.26 (m, 5 H, Ph),
5.60 (s, 1 H, PhCH), 5.28 (d, J1,2 8.4 Hz, H-1), 4.50

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D. Keglevic et al./Carbohydrate Research 313 (1998) 1±14
9
(dd, 1 H, J3,4 8.8 Hz, H-3), 4.40 (q, 1 H, JCH,Me
6.8 Hz, ꢃ-CH Lact), 4.38 (dd, 1 H, J6a,6b 10.4 Hz,
H-6a), 4.33 (dd, 1 H, J2,3 10.4 Hz, H-2), 4.18 (2 d, 2
H, ABq, J 17.1 Hz, OCH2COCH3), 3.82 (t, 1 H,
J6b,5 10.2 Hz, H-6b), 3.76 (t, 1 H, J4,5 9.4 Hz, H-4),
3.65±3.57 (m, 1 H, J5,6a 4.8 Hz, H-5), 3.24 (s, 3H,
CO2Me Lact), 2.02 (s, 3 H, OCH2COCH3), 1.29 (d,
3 H, JMe,CH 6.8 Hz, Me Lact). Anal. Calcd for
C28H29NO10: C, 62.33; H, 5.42; N, 2.60. Found: C,
62.48; H, 5.49; N, 2.50.
1 H, CH2±CH ˆ CH2), 5.48 (s, 1 H, PhCH), 5.47
(d, 1 H, J1,2 8.71 Hz, H-10), 5.04±4.92 (2m, each 1
H, CH2±CH ˆ CH2), 5.02 (d, 1 H, J1,2 8.18 Hz, H-
1), 4.81 and 4.50 (2 d, ABq, 2H, J 12.35 Hz,
PhCH2), 4.55 and 4.48 (2d, ABq, 2H, J 11.93 Hz,
PhCH2), 4.43 (dd, 1H, J3,4 8.7 Hz, J3,2 10.39 Hz, H-
30), 4.39 (q, JCH,Me 7.0 Hz, ꢃ-CH Lact), 4.27 (dd,
1H, J3,4 8.4 Hz, J3,2 10.39 Hz, H-3), 4.24 (dd, 1 H,
H-2), 4.22 (dd, 1 H, J6a,5 5 Hz, J6a,6b 10.4 Hz, H-
60a), 4.20 and 3.89 (2m, each 1 H, CH2±
CH ˆ CH2), 4.19 (t, 1 H, J4,5 9.3 Hz, H-4), 4.16
(dd, 1 H, H-20), 3.67 (t, 1 H, J4,5 9.3 Hz, H-40), 3.53
(t, 1 H, J6b,5 10.4 Hz, H-60b), 3.58±3.36 (m, 4 H, H-
6a, H-60b, H-5, H-50), 3.25 (s, 3 H, CO2Me Lact),
1.27 (d, 3 H, JMe,CH 7.0 Hz, Me Lact). Calcd for
C56H54N2O15: C, 67.59; H, 5.47; N, 2.81. Found:
C, 67.76; H, 5.58; N, 2.85.
4,6-O-Benzylidene-2-deoxy-3-O-[(R)-1-(meth-
oxycarbonyl)ethyl]-2-phthalimido-b-d-glucopyran-
osyl trichloroacetimidate (8).ÐTo a stirred solution
of hemiacetal 6 (160 mg, 0.33 mmol) in dichlor-
omethane (5 mL) were added trichloroacetonitrile
(460 mL, 4.6 mmol) and DBU (42 mL, 0.28 mmol) at
ꢂ
0 C under N2. The mixture was stirred for 2 h at
room temperature when TLC (1:1 EtOAc±petro-
leum ether) indicated the disappearance of 6 (Rf
0.35) and presence of a new compound (Rf 0.80).
Column cromatography (2:1 petroleum ether±
EtOAc) of the partially concentrated solution
a€orded 8 as an amorphous mass (170.8 mg, 82%),
1H NMR (CDCl3): ꢁ 8.62 (s, 1 H, NH), 7.89±7.72
(m, 4 H, Phth), 7.48±7.38 (m, 5 H, Ph), 6.59 (d, J1,2
8.71 Hz, H-1), 5.62 (s, 1 H, PhCH), 4.57±4.38 (m, 4
H, H-3, -6a, -2, ꢃ-CH Lact), 3.89±3.30 (m, 3 H, H-
6b, -4, -5), 3.25 (s, 3 H, CO2Me Lact), 1.30 (d, 3 H,
JMe,CH 6.7 Hz, Me Lact). Anal. Calcd for
C27H25Cl3N2O9: C, 51.65; H, 4.01; N, 4.46. Found:
C, 51.40; H, 4.26; N, 4.76.
(b) To a stirred mixture of 9 (106 mg, 0.2 mmol)
and powdered molecular sieves (200 mg) in dry
CH2Cl2 (4 mL) cooled to 0 C, was added, under
ꢂ
N2, a 0.1 M solution of Me3SiOTf in dry CH2Cl2
(600 ꢄL) followed by a solution of 8 (163 mg,
0.26 mmol) in CH2Cl2 (4 mL), and stirring was
continued at room temperature overnight. The
mixture was neutralised with Et3N and further pro-
cessed as described above; column chromatography
(twice) gave pure 10 (131 mg, 66%) indistinguish-
able (Rf, 1H NMR) from that obtained under (a).
Allyl O-(2-amino-4,6-O-benzylidene-3-O-[(R)-
1-carboxyethyl]-2-deoxy-b-d-glucopyranosyl 10,20-
lactam)-(1!4)-2-acetamido-3,6-di-O-benzyl-2-
deoxy-b-d-glucopyranoside (12).ÐThe disaccharide
10 (150 mg, 0.15 mmol) was treated with anhydrous
LiI (450 mg, 3.4 mmol) in dry pyridine (6 mL) con-
taining granular molecular sieves at 107 ꢂC for 20 h
under N2 as described for 4. Evaporation and co-
evaporation in vacuo, dissolution of the residue in
2:1 CHCl3±water, acidi®cation of the aqueous
layer with 0.1 M HCl to pH 3, extraction of the
liberated acid with CHCl3 (4Â), followed by drying
(Na2SO4) and removal of the solvent, left a syrup
that was puri®ed by column chromatography (6:1
toluene±2-propanol), yielding the acid 11 (114 mg,
77%), TLC (6:1 toluene±2-propanol): Rf 0.40 as an
amorphous mass that was used directly in the next
Allyl O-(4,6-O-benzylidene-2-deoxy-3-O-[(R)-1-
(methoxycarbonyl)ethyl]-2-phthalimido-b-d-gluco-
pyranosyl-(1!4)-3,6-di-O-benzyl-2-deoxy-2-phthal-
imido-b-d-glucopyranoside (10).Ð(a) A mixture of
imidate 8 (163 mg, 0.26 mmol), allyl 3,6-di-O-ben-
zyl-2-deoxy-2-phthalimido-ꢀ-d-glucopyranoside [8,
21,22] 9 (106 mg, 0.2 mmol) and AgOTf (67 mg,
0.26 mmol) was dried in high vacuo; the ¯ask was
then opened to N2, dry CH2Cl2 (5 mL) was injected
through a septum, and the reaction was stirred at
room temperature in the dark for 48 h. The mixture
was diluted with CH2Cl2 ®ltered through Celite,
and the combined ®ltrate and washings were con-
centrated. Column chromatography (5:1 toluene±
EtOAc) of the residue a€orded 10 (125 mg, 63%)
as a colourless syrup, TLC (5:1 toluene±EtOAc):
Rf 0.60; recoveries of the acceptor 9 and the hemi-
acetal 6 (eluted with 1:1 toluene±EtOAc) were 21
and 13% respectively. Compound 10 had [ꢃ]d +21
1
step. Compound 11, H NMR (CDCl3): ꢁ 7.9 and
7.7 (2m, 8 H, 2ÂPhth), 7.4±6.9 (m, 15 H, 3ÂPh),
5.62±5.54 (m, 1 H, CH2±CH ˆ CH2), 5.49 (s, 1 H,
PhCH), 5.48 (d, 1 H, J1,2 7.9 Hz, H-10), 5.03, 5.00,
4.96, 4.93 (4m, 2 H, CH2±CH ˆ CH2), 5.01 (d, 1 H,
J1,2 8.2 Hz, H-1), 4.81 and 4.49 (2d, ABq, J 12.6 Hz,
PhCH2O), 4.53 and 4.47 (2d, ABq, 2 H, J 12.0 Hz,
1
(c 1); H NMR (CDCl3): ꢁ 7.96±7.66 (m, 8 H,
2ÂPhth), 7.43±6.90 (m, 15 H, 3ÂPh), 5.68±5.54 (m,

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D. Keglevic et al./Carbohydrate Research 313 (1998) 1±14
10
PhCH2), 4.41 (t, 1 H, J3,4 8.9 Hz, J3,2 10 Hz, H-30),
4.39 (q, 1 H, JCH,Me 6.9 Hz, ꢃ-CH Lact), 4.3±4.0 (m,
6 H, H-2, 3, 4 H-20, 60a, 1/2 CH2±CH ˆ CH2), 3.92±
3.86 (m, 1 H, 1/2 CH2-CH ˆ CH2), 3.66 (t, 1 H, J4,5
9 Hz, H-40), 3.53 (t, 1 H, J6b,5 ˆ J6b,6a 10.2 Hz, H-
60b), 3.56±3.30 (m, 4 H, H-5, 6a, 6b, H-50), 1.27 (d,
3H, JMe,CH 6.9 Hz, Me Lact).
Ac2O was destroyed by 96% ethanol, and the
solution concentrated to a syrup which was pur-
i®ed by column chromatography with 10:10:1
toluene±EtOAc±MeOH to give ꢂ12 (Rf 0.45, 57 mg,
76%) as a solid, mp 240±245 C (decomp., soft-
ening at 190 C), [ꢃ]d +13ꢂ (c 0.9); H NMR
(CDCl3): ꢁ 7.47±7.30 (m, 15 H, 3ÂPh), 6.45 (bs, 1
H, NH0), 5.94±5.81 (m, 1 H, CH2±CH ˆ CH2), 5.61
(d, 1 H, JNH,2 7.4 Hz, NH), 5.46 (s, 1 H, PhCH),
5.29±5.17 (m, 2 H, CH2±CH ˆ CH2), 4.96 (d, 1 H,
J1,2 7.9 Hz, H-1), 4.84, 4.77, 4.59, 4.55 (4d, 4 H,
ABq, J ꢀ 12 Hz, 2ÂPhCH2), 4.48 (d, 1 H, J1,2
8.2 Hz, H-10), 4.34±4.18 (m, 3H, H60a, ꢃ-CH Lact,
ꢂ
1
A stirred solution of 11 (97 mg, 0.1 mmol) in n-
butanol (15 mL) was treated with ethylenediamine
ꢂ
(1 mL) at 100 C for 20 h under N2. After eva-
poration and co-evaporation with toluene (4Â), the
ꢂ
residue was dissolved in 1:1 Ac2O±pyridine at 4 C
and left at room temperature overnight. Excess
Table 4
Crystal data and summary of experimental details for 3 and 7
Compound
3
7
Molecular formula
Mr
Data collection
C19H23NO6
361.39
C28H29NO10
539.54
Difractometer
Radiation, l(A)
Enraf±Nonius CAD4F, rot.anode
MoKꢃ, 0.71073
Enraf±Nonius CAD4
CuKꢃ, 1.54184
295(3)
T=ꢃK†
154
25
No. of re¯ections for cell determination
15
11±21
2.38±74.33
0,9; 15,0; 0,24
!=2Â
ꢅ Range for cell determination (ꢂ)
ꢅ Range for intensity measurements (ꢂ)
hkl Range
Scan
2.03±24.97
11,11; 23,0; 11,0
!=2Â
Á!
No. of measured re¯ections
0.73+0.31tnÂ
2133
2109
3552
3336
1289
No. of symm. independent re¯ections
No. of symm. ind. re¯. with Fo > 4ꢂꢃFo†
665
Crystal data
Solvent
EtOAc±petroleum ether
EtOAc±petroleum ether
0.072Â0.036Â0.324
Colourless
8.435(1)
Crystal size (mm)
Crystal colour
a (A)
Colourless
9.5278
20.0326
9.7031
97.058
1837.96
Monoclinic
P21
b (A)
c (A)
14.044(2)
22.649(2)
90.00
2682.8(6)
Orthorhombic
P212121
ꢀ (ꢂ)
V (A3)
Crystal class
Space group
Z
Dx (g cm
ꢄ (cm
F (000)
4
4
1.3356(3)
8.2 (CuKꢃ)
1136
3
)
1.3060
0.9 (MoKꢃ)
768
1)
Solution and re®nement
Programs used
No. of parameters
Minimisation function
HELENA,SHELXS86,SHELXL93
184
HELENA,SHELXS86,SHELXL93
331
2
2
ÆwꢃjF2oj jF2c j†
ÆwꢃjF2oj jF2cj†
2
w ˆ 1:0
w ˆ q=‰ꢂ2ꢃF2o† ‡ ꢃaP† ‡ bPŠ
q ˆ 1:0, a ˆ 0:0622, b ˆ 0:02
p ˆ ‰maxꢃF2o† ‡ 2F2cŠ=3
0.0529 (R1)
RꢃF†zaFo > 4ꢂꢃFo†
RꢃF† all re¯ections
wRꢃF2† all re¯ections
S
0.1703 (R1)
0.3412 (R1)
0.4471 (wR2)
1.635 all re¯ections
Ð
0.3412 (R1)
0.1526 (wR2)
0.797 all re¯ections
<0.389
ꢃÁ=ꢂ†
max
Áꢆmax (eA 3),ÁꢆminꢃeA
3
†
1.01, 0:82
0.21, 0:23

Â
D. Keglevic et al./Carbohydrate Research 313 (1998) 1±14
11
1/2 OCH2±CH ˆ CH2), 4.12±4.06 (m, 2 H, H-6a, 1/
2 OCH2±CH ˆ CH2), 4.02 (t, 1 H, J4,3 8.7, J4,5
9.5 Hz, H-4), 3.82±3.51 (m, 6 H, H-2, 3, 6b, H-40,
50, 60b), 3.46 (t, J3,2 9.5, J3,4 9.2 Hz, H-30), 3.26 (t, 1
H, H-20), 3.20 (m, 1 H, H-5), 1.87 (s, 3 H, NAc),
1.49 (d, 3 H, JMe,CH 6.9 Hz, Me Lact). Anal. Calcd
for C41H48N2O11: C, 66.11; H, 6.49; N, 3.76.
Found: C, 66.21; H, 6.28; N, 3.56.
Table 5
Final atomic coordinates and isotropic thermal parameters of non-hydrogen atoms for 3 (molecules A and B)
Atom
x
y
z
Uiso (A2)
Molecule A
O-1
O-3
O-4
O-5
0.0745(16)
0.2154(16)
0.2773(17)
0.1505(15)
0.2767(18)
0.0292(19)
0.0295(19)
0.060(3)
0.129(2)
0.156(2)
0.243(2)
0.168(3)
0.246(3)
0.364(3)
0.005(3)
0.033(3)
0.077(3)
0.121(2)
0.207(3)
0.040(3)
0.2711(11)
0.4098(12)
0.5135(11)
0.37483(0)
0.5461(13)
0.2910(13)
0.3044(13)
0.3363(15)
0.3450(15)
0.4121(14)
0.4430(14)
0.4420(14)
0.4796(16)
0.5395(16)
0.2524(16)
0.1805(17)
0.159(2)
0.3826(14)
0.3689(17)
0.3228(15)
0.6123(10)
0.6352(11)
0.6991(11)
0.7401(10)
0.7172(11)
0.6533(11)
0.0854(16)
0.4628(16)
0.2659(16)
0.0340(15)
0.0353(18)
0.5719(19)
0.3554(19)
0.118(2)
0.273(2)
0.321(2)
0.230(2)
0.081(2)
0.018(3)
0.177(3)
0.044(3)
0.067(3)
0.190(3)
0.550(2)
0.682(3)
0.495(3)
0.023(4)
0.022(4)
0.025(4)
0.017(4)
0.033(5)
0.040(5)
0.021(5)
0.021(6)
0.019(6)
0.009(5)
0.015(5)
0.020(6)
0.033(7)
0.032(7)
0.032(7)
0.038(8)
0.061(10)
0.013(5)
0.040(8)
0.023(6)
0.014(5)
0.032(7)
0.044(8)
0.024(6)
0.045(8)
0.030(7)
O-6
O-33
N-2
C-1
C-2
C-3
C-4
C-5
C-6
C-7
C-11
C-12
C-13
C-31
C-32
C-33
C-71
C-72
C-73
C-74
C-75
C-76
0.3943(16)
0.5329(14)
0.5654(13)
0.4592(17)
0.3206(15)
0.2881(12)
0.2227(15)
0.2339(17)
0.2838(18)
0.3226(17)
0.3114(17)
0.2615(17)
Molecule B
O-1
O-3
O-4
O-5
0.5464(17)
0.9178(16)
0.7105(17)
0.4861(16)
0.4702(16)
1.0476(18)
0.8241(19)
0.582(2)
0.727(2)
0.780(2)
0.671(2)
0.531(2)
0.423(3)
0.601(2)
0.420(3)
0.411(3)
0.295(3)
1.007(3)
1.162(2)
0.958(2)
0.0202(12)
0.1640(12)
0.2641(12)
0.1194(12)
0.2886(12)
0.0394(12)
0.0546(13)
0.0895(14)
0.0880(15)
0.1636(15)
0.1930(14)
0.1891(15)
0.2195(15)
0.2905(16)
0.0049(16)
0.0726(16)
0.0990(18)
0.1410(16)
0.1379(15)
0.0705(15)
0.3668(10)
0.4017(11)
0.4678(11)
0.4991(10)
0.4642(12)
0.3981(11)
0.3752(17)
0.2988(15)
0.1969(17)
0.2604(16)
0.1273(16)
0.5488(17)
0.4386(19)
0.368(2)
0.330(3)
0.326(2)
0.211(2)
0.249(3)
0.138(3)
0.097(3)
0.447(3)
0.457(3)
0.435(3)
0.412(3)
0.374(2)
0.470(2)
0.030(5)
0.021(4)
0.024(4)
0.022(4)
0.022(4)
0.032(5)
0.015(5)
0.011(5)
0.022(6)
0.015(5)
0.009(5)
0.019(6)
0.027(7)
0.026(6)
0.037(8)
0.029(7)
0.040(8)
0.027(7)
0.022(6)
0.017(6)
0.012(5)
0.035(7)
0.026(6)
0.037(8)
0.037(7)
0.044(8)
O-6
O-33
N-2
C-1
C-2
C-3
C-4
C-5
C-6
C-7
C-11
C-12
C-13
C-31
C-32
C-33
C-71
C-72
C-73
C-74
C-75
C-76
0.6468(16)
0.7126(17)
0.7522(16)
0.7261(18)
0.6603(18)
0.6206(17)
0.0794(16)
0.1932(12)
0.1786(13)
0.0501(17)
0.0637(12)
0.0491(13)

Â
D. Keglevic et al./Carbohydrate Research 313 (1998) 1±14
12
X-ray structure determination of 3 and 7. The
HELENA [33]. The structures were solved by
SHELXS-86 [34] and re®ned by full-matrix least-
squares minimisation by SHELXL-93 [35] using F2
values. Due to poor ratio of re¯ections per vari-
able, 3 was re®ned isotropicaly, only. Hydrogen
atoms were generated on the stereochemical
grounds and re®ned riding on their respective car-
bon atoms. The O±H and N±H bond distances
were normalised to the values obtained by neutron
di€raction (O±H 0.983 A and N±H 1.009 A).
Details of the re®nement procedure are given in the
Table 4. During the structure determinations, the d
enantiomers were selected according to the assign-
ment R at C-5; chirality on C-31 (ꢁ-lactam residue)
proved to be R. The molecular geometries were
calculated by program PLATON [24] and ORTEP
crystals for X-ray analysis were ꢂ grown from
EtOAc±petroleum ether (b.p. 50±60 C) for both 3
and 7 at 4 ꢂC for several weeks. Numerous
attempts to get good quality crystals of 3 were not
successful. Only very tiny plates were obtained.
The crystal data and summary of experimental
details are listed in Table 4. The X-ray intensity
data were collected with an Enraf±Nonius CAD4F
di€ractometer using graphite-monochromatised
MoKꢃ radiation and rotating anode for 3 and
Enraf±Nonius CAD4 di€ractometer using gra-
phite-monochromatised CuKꢃ radiation for 7 [32].
There were no signi®cant variations in intensity for
the standard re¯ections. The data were corrected
for Lorentz and polarisation e€ects using program
Table 6
Final atomic coordinates and equivalent isotropic thermal parameters of non-hydrogen atoms for 7
Atom
x
y
z
Ueq (A2)a
O-1
O-3
O-4
O-5
0.4469(9)
0.5678(11)
0.4097(10)
0.3478(9)
0.2540(10)
0.7357(12)
0.8558(10)
0.5624(12)
0.8832(15)
0.9319(14)
0.6766(12)
0.4869(13)
0.5355(14)
0.5494(16)
0.3937(15)
0.3709(15)
0.2279(17)
0.2697(18)
0.4605(16)
0.624(2)
0.6390(17)
0.8280(17)
0.9290(11)
1.0899(11)
1.1619(8)
1.0732(12)
0.9123(12)
0.8403(7)
0.6743(18)
0.669(2)
0.3595(6)
0.3616(6)
0.5411(6)
0.4768(5)
0.6578(6)
0.3558(9)
0.4335(6)
0.1602(6)
0.3130(10)
0.4083(8)
0.3108(7)
0.4203(9)
0.3622(9)
0.4262(9)
0.4832(10)
0.5406(9)
0.6036(9)
0.5992(9)
0.3962(11)
0.3788(11)
0.3967(11)
0.3517(9)
0.2720(5)
0.2695(6)
0.1837(9)
0.1003(6)
0.1028(5)
0.1886(7)
0.2129(10)
0.4015(10)
0.3665(11)
0.3667(13)
0.3776(9)
0.6599(7)
0.7463(9)
0.8052(6)
0.7776(7)
0.6912(9)
0.6323(5)
0.2535(4)
0.0496(3)
0.0423(3)
0.1968(3)
0.0870(3)
0.3051(4)
0.1728(3)
0.1744(4)
0.0508(4)
0.0259(5)
0.1672(3)
0.2075(5)
0.1525(5)
0.0989(5)
0.0931(5)
0.1487(5)
0.1390(5)
0.0371(5)
0.3121(5)
0.3362(6)
0.3995(5)
0.1771(5)
0.1909(3)
0.2042(3)
0.2188(3)
0.2201(3)
0.2068(3)
0.1922(3)
0.1784(6)
0.0038(6)
0.0551(6)
0.0150(7)
0.0268(6)
0.0168(3)
0.0194(4)
0.0683(5)
0.1145(4)
0.1118(3)
0.0629(5)
0.060(4)
0.068(4)
0.064(4)
0.058(3)
0.065(4)
0.113(5)
0.062(3)
0.078(4)
0.151(7)
0.117(6)
0.046(4)
0.048(5)
0.054(6)
0.056(5)
0.066(6)
0.056(5)
0.077(7)
0.069(6)
0.081(7)
0.076(7)
0.121(9)
0.053(5)
0.047(5)
0.065(6)
0.080(7)
0.072(6)
0.061(6)
0.047(5)
0.068(6)
0.068(6)
0.109(8)
0.086(8)
0.106(8)
0.065(6)
0.097(8)
0.105(8)
0.076(7)
0.084(7)
0.066(6)
O-6
O-12
O-21
O-28
O-33
O-34
N-2
C-1
C-2
C-3
C-4
C-5
C-6
C-7
C-11
C-12
C-13
C-21
C-22
C-23
C-24
C-25
C-26
C-27
C-28
C-31
C-32
C-33
C-35
C-71
C-72
C-73
C-74
C-75
C-76
0.6078(17)
0.835(3)
1.0936(17)
0.2898(12)
0.2099(11)
0.2283(12)
0.3266(13)
0.4066(10)
0.3881(10)
aUeq ˆ ꢃ1=3†ÆiÆjUijaiÃaÃj ai Áaj

Â
D. Keglevic et al./Carbohydrate Research 313 (1998) 1±14
13
plot for 7 was prepared by program ORTEP [25].
Ball and stick molecular structure presentation and
packing diagrams for 3 were prepared by program
PLUTON [24]. The ®nal atomic coordinates and
equivalent isotropic thermal parameters for 3 and 7
are listed in the Tables 5 and 6, respectively. Cal-
culations were performed on Silicon Graphics
INDIGO2 workstation of the Laboratory for che-
mical and biological crystallography, Department
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of Physical Chemistry, Ruder Boskovic Institute,
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4. Supplementary material
Tables of atomic coordinates, thermal para-
meters, bond lengths, and bond angles for 3 and 7
have been deposited with the Cambridge Crystal-
lographic Data Centre. These tables may be
obtained, on request, from the Director, Cam-
bridge Crystallographic Data Centre, 12 Union
Road, Cambridge, CB2 1EZ, UK.
[17] A.J. Wood, P.R. Jenkins, J. Fawcett, and
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Acknowledgements
[22] Vandana, O. Hindsgaul, and J.U. Baenziger, Can.
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This work was supported by Ministry of Science
and Technology of Republic of Croatia grants
00980704 and 00980608. The authors thank
Professor Dr. Jan Kroon, Head, Department of
Crystal and Structural Chemistry, Bijvoet Centre
for Biomolecular Research, Utrecht University, for
enabling the use of high-intensity X-ray beam sui-
table for data collection and his valuable comments.
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