NꢀAcyllactosylamine derivatives
Russ.Chem.Bull., Int.Ed., Vol. 55, No. 7, July, 2006
1265
carbonylglycine (2a), Nꢀbenzyloxycarbonylglycylglycine (2b),
or NꢀbenzyloxycarbonylꢀLꢀserine (5)) (1.1 mmol), and NHS
(0.126 g, 1.1 mmol) was dissolved with heating to 40 °C in dry
DMSO (4 mL). The solution was cooled to 15 °C, and DCC
(0.247 g, 1.2 mmol) was added. The reaction mixture was stirred
for 1 h and kept for 23 h at 15 °C until lactosylamide was
converted almost completely (monitoring by electrophoresis).
The precipitate of N,N´ꢀdicyclohexylurea was filtered off and
washed with DMSO (0.5 mL). The filtrate was added with stirꢀ
ring to Et2O (45 mL), and, when the solution became clear, the
liquid was decanted from the oily precipitate. The precipitate
was triturated several times with Et2O (each portion 10 mL)
until a thick paste formed; this was triturated several times with
acetone (each portion 5 mL) until a powder formed. The powꢀ
der was filtered off, washed with acetone (2×5 mL) and Et2O,
and dried. The resulting compounds 3a—c and 7a were purified
as described below for each particular case, and compound 6a
was used without purification
Lactosylamides 4a—c, 6b, 7b (general procedure). NꢀBenzylꢀ
oxycarbonyllactosylamide (0.5 mmol) was dissolved in water
with heating to 40 °C (3a, 3b and 6a, in 8 mL of water, and 3c
and 7a in 30 mL of water). The solution was cooled to 20 °C,
10% Pd/C (its mass was half that of lactosylamide) was added
under argon, and the mixture was hydrogenated with vigorous
stirring in a gentle flow of H2 for 8—10 h (monitoring by paper
electrophoresis). The catalyst was filtered off and washed with
water containing 10% MeOH (2×6 mL). The solution was twice
concentrated and filtered (0.45 µm filter). Subsequent isolation
of lactosylamides 4a—c, 6b, 7b is described below separately for
each product.
pound 1 (0.4 g, 1 mmol) and Nꢀbenzyloxycarbonylglycylglycine
(2b) (0.29 g, 1.1 mmol). The crude product 3b was dissolved in
water (1.5 mL), PriOH was added with stirring until the solution
became turbid, and the mixture was kept for 16 h at 5 °C. The
gelꢀlike precipitate was filtered off, washed with 20% aq. PriOH,
acetone, and Et2O, and dried to give 0.46 g (70%) of amorphous
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compound 3b, [α]D +2.7 (c 1, H2O). Found (%): C, 47.19;
H, 6.21; N, 8.43; H2O, 3.03. C26H38N4O15•H2O. Calcuꢀ
1
lated (%): C, 46.99; H, 6.07; N, 8.43; H2O, 2.71. H NMR, δ:
3.46—3.61 (m, 2 H); 3.61—3.86 (m, 8 H); 3.91 (br.s, 5 H); 3.98
(br.s, 3 H); 4.45 (d, 1 H, H(1) Gal, J = 7.5 Hz); 5.02 (d, 1 H,
H(1) Glc, J = 9.0 Hz); 5.16 (s, 2 H, CH2O); 7.44 (br.s, 5 H, Ph).
4ꢀOꢀ(βꢀDꢀGalactopyranosyl)ꢀNꢀtriglycylꢀβꢀDꢀglucopyranoꢀ
sylamine (4b) was obtained by hydrogenation of compound 3b
(0.33 g, 0.5 mmol). The solution was concentrated to 0.5 mL,
MeOH was added with stirring until turbidity appeared, and the
mixture was left for 16 h at 5 °C. The precipitate was filtered off,
washed with MeOH and Et2O, and dried to give 0.22 g (88%) of
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amorphous compound 4b, [α]D +3.0 (c 1, H2O). Found (%):
C, 41.92; H, 6.48; N, 10.39. C18H32N4O13. Calculated (%):
C, 42.19; H, 6.29; N, 10.93. 1H NMR, δ: 3.46 (br.s, 2 H,
CH2NH2); 3.47—3.61 (m, 2 H); 3.61—3.86 (m, 8 H); 3.86—3.98
(m, 2 H); 4.01 (br.s, 4 H, 2 CH2 NH); 4.45 (d, 1 H, H(1) Gal,
J = 7.5 Hz); 5.02 (d, 1 H, H(1) Glc, J = 9.0 Hz).
4ꢀOꢀ(βꢀDꢀGalactopyranosyl)ꢀNꢀ(Nꢀbenzyloxycarbonylpentaꢀ
glycyl)ꢀβꢀDꢀglucopyranosylamine (3c) was obtained from comꢀ
pound 4b (0.51 g, 1 mmol) and Nꢀbenzyloxycarbonylglycylꢀ
glycine (2b) (0.29 g, 1.1 mmol). The crude product 3c was
treated with water (25 mL) at 60 °C and the precipitate was
filtered off. The filtrate was concentrated to 10 mL, then PriOH
(8 mL) was added with stirring, and the mixture was kept for
16 h at 5 °C. The gelꢀlike precipitate was filtered off, washed
with 80% aq. PriOH, acetone, and Et2O, and dried to give 0.47 g
4ꢀOꢀ(βꢀDꢀGalactopyranosyl)ꢀNꢀ(Nꢀbenzyloxycarbonylꢀ
diglycyl)ꢀβꢀDꢀglucopyranosylamine (3a) was obtained from
4ꢀOꢀ(βꢀDꢀgalactopyranosyl)ꢀNꢀglycylꢀβꢀDꢀglucopyranosylamine
(1) (0.4 g, 1 mmol) (see Ref. 8) and Nꢀbenzyloxycarbonylglycine
(2a) (0.23 g, 1.1 mmol). The crude product 3a was dissolved
with heating to 40 °C in a mixture of water (1.1 mL) and MeOH
(20 mL), then PriOH (4 mL) was added with stirring, and the
mixture was kept for 16 h at 5 °C. The gelꢀlike precipitate was
filtered off, washed with MeOH and Et2O, and dried to give
0.46 g of pure compound 3a. The mother liquor was concenꢀ
trated to dryness to give additional 0.06 g of amorphous comꢀ
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(59%) of amorphous compound 3c, [α]D +2.0 (c 0.5, H2O).
Found (%): C, 45.58; H, 6.16; N, 10.66; H2O, 4.86.
C30H44N6O17•2 H2O. Calculated (%): C, 45.22; H, 6.07;
N, 10.55; H2O, 4.52. 1H NMR, δ: 3.46—3.61 (m, 2 H);
3.61—3.86 (m, 8 H); 3.91 (br.s, 5 H); 3.98 (br.s, 7 H); 4.45 (d,
1 H, H(1) Gal, J = 7.5 Hz); 5.02 (d, 1 H, H(1) Glc, J = 9.0 Hz);
5.17 (s, 2 H, CH2O); 7.44 (br.s, 5 H, Ph).
4ꢀOꢀ(βꢀDꢀGalactopyranosyl)ꢀNꢀpentaglycylꢀβꢀDꢀglucoꢀ
pyranosylamine (4c) was prepared by hydrogenation of comꢀ
pound 3c (0.4 g, 0.5 mmol). The solution was concentrated to
2.5 mL and kept for 16 h at 5 °C. The precipitate was filtered off,
washed with cold water, MeOH, and Et2O, and dried to give
18
pound 3a in a similar way (total yield 86%), [α]D +1.5
(c 1, H2O). Found (%): C, 46.97; H, 6.31; N, 6.96; H2O, 3.07.
C24H35N3O14•H2O. Calculated (%): C, 47.44; H, 6.14; N, 6.92;
H2O, 2.97. 1H NMR, δ: 3.40—3.60 (m, 2 H); 3.60—4.04
(m, 14 H); 4.45 (d, 1 H, H(1) Gal, J = 7.5 Hz); 5.02 (d, 1 H,
H(1) Glc, J = 9.0 Hz); 5.17 (s, 2 H, CH2O); 7.44 (br.s, 5 H, Ph).
4ꢀOꢀ(βꢀDꢀGalactopyranosyl)ꢀNꢀdiglycylꢀβꢀDꢀglucopyranosylꢀ
amine (4a) was obtained by hydrogenation of compound 3a (0.3 g,
0.5 mmol). The solution was concentrated to 0.5 mL, and then
MeOH (2 mL) was added with stirring. The mixture was kept for
16 h at 5 °C. The precipitate was filtered off, washed with MeOH
and Et2O, and dried to give 0.2 g (86%) of amorphous comꢀ
pound 4a, [α]D18 +3.6 (c 1, H2O). Found (%): C, 41.22; H, 6.59;
N, 8.77; H2O, 1.88. C16H29N3O12•0.5 H2O. Calculated (%):
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0.26 g (80%) of amorphous 4c, [α]D +3.1 (c 0.5, H2O).
Found (%): C, 40.79; H, 6.35; N, 13.40; H2O, 2.90.
C22H38N6O15•H2O. Calculated (%): C, 40.99; H, 6.26; N, 13.04;
1
H2O, 2.80. H NMR, δ: 3.43 (br.s, 2 H, CH2NH2); 3.45—3.61
(m, 2 H); 3.61—3.85 (m, 8 H); 3.86—3.96 (m, 2 H); 4.02 (br.s,
8 H, 4 CH2 NH); 4.45 (d, 1 H, H(1) Gal, J = 7.5 Hz); 5.02 (d,
1 H, H(1) Glc, J = 9.0 Hz).
4ꢀOꢀ(βꢀDꢀGalactopyranosyl)ꢀNꢀ(Nꢀbenzyloxycarbonylꢀ
Lꢀseryldiglycyl)ꢀβꢀDꢀglucopyranosylamine (6a) was obtained from
compound 4a (0.464 g, 1 mmol) and Nꢀbenzyloxycarbonylꢀ
Lꢀserine (5) (0.263 g, 1.1 mmol). The crude product (yield 0.64 g,
94%) was used without purification for the synthesis of comꢀ
pound 6b.
1
C, 41.38; H, 6.51; N, 9.05; H2O, 1.94. H NMR, δ: 3.45 (br.s,
2 H, CH2NH2); 3.46—3.60 (m, 2 H); 3.60—3.85 (m, 8 H);
3.85—3.94 (m, 2 H); 4.02 (br.s, 2 H, CH2 NH); 4.45 (d, 1 H,
H(1) Gal, J = 7.5 Hz); 5.02 (d, 1 H, H(1) Glc, J = 9.0 Hz).
4ꢀOꢀ(βꢀDꢀGalactopyranosyl)ꢀNꢀ(Nꢀbenzyloxycarbonyltriꢀ
glycyl)ꢀβꢀDꢀglucopyranosylamine (3b) was obtained from comꢀ
4ꢀOꢀ(βꢀDꢀGalactopyranosyl)ꢀNꢀ(Lꢀseryldiglycyl)ꢀβꢀDꢀglucoꢀ
pyranosylamine (6b) was obtained by hydrogenation of comꢀ
pound 6a (0.34 g, 0.5 mmol). The solution was concentrated to