JPH0441154B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel oligomannoside and a method for producing the same.
The present invention relates to a branched mannan having α1-3 bonds and α1-6 bonds, and a method for producing the same.

Mannan is a polysaccharide that is widely distributed from higher plants to microorganisms. In recent years, research on their chemical structures has progressed, and structural formulas of several repeating units have been published. For example, yeast mannan and potato mannan are proteomannans that exist on the surface of cells (T. Nakajima, H. Sasaki,
M. Sato, K. Tamari and K. Matsuda, J.
Biochem, (Tokyo) 82, 1657-1662) A complex branched structure is considered. Since these mannans exist on the surface layer, it is highly likely that they are also involved in recognition phenomena between organisms. Furthermore, antitumor activity has been reported for some mannans. The present inventors are conducting research on the synthesis of oligomannosides having accurate structures, with the aim of elucidating the correlation between these biological functions, antitumor activities, and mannan structure.

As part of the above research, the present inventors conducted research on the synthesis of the partial structure of proteoheteroglycan, which is present in the cell wall of the rice blast fungus and has the following structural formula, and succeeded in synthesizing M5 model and M9 model I. (Japanese Patent Application Laid-Open No. 57-72996, Patent Application No. 146662/1983)
(see specification).

(In the formula, M represents a mannose residue, G represents a glucose residue, and G represents a galactofuranosyl residue.) The present invention was completed in the course of research on the synthesis of the M9 model. The novel oligomannosides of the present invention are represented by the following general formula.

In the above formula, R is a hydrogen atom or an acetyl group,
R' is a hydrogen atom or benzyl group, Y is a hydrogen atom or (In the formula, R represents a hydrogen atom or an acetyl group.)

The pentasaccharide compound in which Y is a hydrogen atom in the above general formula has the formula (1): (In the formula, R′ represents a benzyl group) and the compound represented by formula (2) (In the formula, R is an acetyl group and X is a halogen atom.) It can be obtained by reacting a compound represented by the following formula, followed by deacetylation and debenzylation if necessary.

(3a) R=acetyl group, R'=benzyl group (3b) R=H, R'=benzyl group (3c) R=H, R'=H The nonasaccharide compound which is another object compound of the present invention is:
Compound (3a) and formula (9) (In the formula, R is an acetyl group and X is a halogen atom.) It can be obtained by reacting a compound represented by the following formula, followed by deacetylation and debenzylation if necessary.

(10a) R=acetyl group, R'=benzyl group (10b) R=H, R'=benzyl group (10c) R=H, R'=H Compound (1), which is the starting material of the present invention, is, for example, It can be synthesized as follows (Patent application 1983-
146664).

First, compound (A) (T.Ogawa & K.Sasajma,
(See Carbohydrate Research, 93 (1981), 67-81) , (CH ₃ ) ₃ SiOSO ₂ CF ₃ (TMS Trif), SnCl ₄ ,
Compound (B) is obtained by reacting with benzyl alcohol in the presence of a Lewis acid catalyst such as AlCl ₃ , PCl ₃ or ZnCl ₂ . Suitable solvents include dichloroethane, dichloromethane, chloroform, nitromethane, benzene, toluene, and the like.

The reaction temperature and reaction time are approximately -20 to 50, respectively.
℃, about 1 minute to 48 hours is suitable.

The obtained compound (B) was mixed with MeONa/MeOH,
EtONa/EtOH, i-PrOH/i-PrONa,
Compound (C) is obtained by treatment with an alcoholate such as MeOK/KOH in a solvent such as THF or ether for deacetylation.

The obtained compound (C) is reacted with the compound (A) to obtain the disaccharide compound (D), and the reaction conditions are such that the compound
The reaction conditions are the same as those for (A)→compound (B).

The obtained disaccharide compound (D) was mixed with AgOSO ₂ CF ₃ and Ag ₂
A trisaccharide compound (F) is obtained by reacting with the compound (E) using a silver or mercury compound such as CO ₃ , Ag ₂ O, AgClO ₄ , HgBr ₂ or Hg(CN) ₂ as a catalyst.

(X is a halogen atom) Suitable solvents include dichloroethane, dichloromethane, chloroform, nitromethane, benzene, toluene, etc., and the reaction temperature and reaction time are approximately -20 to 100°C and approximately 1 minute to 48 hours, respectively. Appropriate.

In this reaction, it is preferable to add a molecular sieve for the purpose of removing acids such as HBr generated during the reaction.

The thus obtained trisaccharide compound (F) was converted into the above compound (B).
→ Deacetylation is performed in the same manner as the reaction of compound (C) to obtain the desired triol trisaccharide compound (1).

Compound (2), which is another starting material of the present invention, can be synthesized, for example, as follows (JP-A-57
-Refer to Publication No. 146797).

Compounds that are yet another starting material of the present invention
For example, (9) can be synthesized as follows.

1,2,4,6-tetra-0-benzyl-α-
D-Mannoviranoside (4) and acetobromomannose (5) were reacted in the presence of AgOSO ₂ CF ₃ -MS to produce 2
Compound (9) is obtained by treating compound (8) obtained by obtaining sugar (6), debenzylating it, and then acetylating it by a conventional method with HBr-AcOH in a solvent such as dichloroethane.

The present invention provides a method for reacting the thus obtained compound (1) and compound (2) to obtain a pentasaccharide compound (3), and a method for reacting compound (3) and compound (9) to obtain a nonasaccharide compound (10). This is the way to obtain.

Compound (1) and compound (2), and (3b) and compound
The reaction with (9) is carried out in a solvent such as 1,2-dichloroethane, dichloromethane, chloroform, nitromethane, benzene, toluene, etc. at a temperature of -30℃ to 150℃.
For about 1 to 8 hours, HgHr ₂ , Hg(CN) ₂ , A
This is carried out using a catalyst such as gOSO ₂ CF ₃ , Ag ₂ CO ₃ , Ag ₂ O, AgClO ₄ or the like. At this time, generated during the reaction
For the purpose of removing acids such as HBr, it is preferable to add molecular sieve 4A to the reaction.

The deacetylation reaction of compounds (3a) and (10a) is carried out using a catalyst such as a tertiary organic base such as sodium methoxide, sodium ethoxide, or triethylamine, using methanol, ethanol, n- and iso-propanol, water or The process proceeds satisfactorily in a mixed solvent of these at a temperature of -30°C to 100°C for 0.5 to 30 hours.

The debenzylation reaction of compounds (3b) and (10b) involves converting these compounds into water-ethanol,
THF-ethanol, ethanol, methanol,
This is carried out by dissolving in a solvent or mixed solvent such as acetic acid, THF-water, dioxane-water, DMF, etc., and hydrogenating at normal pressure or under pressure using Pd/C or the like as a catalyst. Appropriate reaction temperature is 0°C to 100°C and reaction time is approximately 1 to 100 hours.

In addition, compounds (3a), (3b), (3c), (6), (7), (8), (9), (10a) obtained in the above steps
),
Both (10b) and (10c) are new compounds synthesized for the first time by the present inventors.

The above novel compounds obtained by the present invention are useful as intermediates in the synthesis of mannans having physiological activities such as antitumor properties, and as reagents in elucidating the biological significance and functions of mannans. It has the following.

The present invention will be explained in more detail with reference to Examples below, but these are not intended to limit the scope of the present invention in any way.

In the examples and reference examples, unless otherwise specified, all C-NMR and H-NMR measurements are
It was carried out in CDCl ₃ solvent at 20°C.

Example 1 2 g of molecular sieves 5A powder and a rotor were placed in a 30 ml brown two-necked flask and stirred at 190° C. under reduced pressure for 7 hours. After cooling to room temperature, dissolve in 10ml of toluene.
Inject _200mg (0.77mM) of _AgOSO2CF3 for 40 minutes under reduced pressure.
The solvent was removed at °C. Compound (1) 200mg after nitrogen substitution
(0.137mM) was injected with 30ml of dichloroethane and stirred at room temperature for 1 hour. After cooling to -15°C, 100 mg (0.147 mM) of compound (2) was added dropwise together with 2 ml of dichloroethane. Stirring for 30 min at −15°C results in TLC.
of compound (2) on (toluene:ethyl acetate 1:1).
The Rf0.55 spot disappeared and a small amount of compound (1)
Along with the Rf0.45 spot, a new Rf0.36 spot appeared along with two traces of Rf0.28 and Rf0.15 spots. After filtering with FC diatomaceous earth, ethyl acetate 100ml
was added, washed twice with saturated sodium bicarbonate solution, washed with saturated saline solution, dried with MgSO ₄ , and the solvent was removed, and a substance with Rf 0.36 was isolated as 140 mg of powdered material using Fractogel PVA2000.

[Properties of compound (3)] Elemental analysis: As C ₁₁₄ H ₁₂₆ O ₃₃ , C: 67.64, H: 6.27 Actual value C: 67.53, H: 6.26 [α] ²⁰ _D +55.4° (C: 0.4, CHCl ₃ ) NMR: δH (CDCl ₂ ): 7.318-7.165 (40H, m aromatic) 2.140-1.961 (21H, m,
7XAc) δC( _CDCl3 ): 101.4( ^l CH173.3HzC-1C), 99.6( ^l
70.9C-1b), 99.6( ^l 73.3, C-1d, C-
1e), 97.8 ( ^l 72, 1 Hz, C-1a) Reference Example 1 3 g of molecular sieves 5A powder and a rotor were placed in a 50 ml brown two-necked flask, and the mixture was stirred at 180° C. under reduced pressure overnight. AgOSO ₃ dissolved in 10ml of toluene after cooling to room temperature
800 mg of CF ₃ was injected, and the solvent was removed under reduced pressure at 40°C.
After nitrogen substitution, 967 mg (1.79 mM) of compound (4) was injected together with 20 ml of dichloroethane, and the mixture was stirred at room temperature for 1 hour. After cooling to -5°C, 733 mg (1.79 mM) of compound (5) was injected dropwise with 2 ml of dichloroethane and stirred for 5 minutes.
1) The 0.13 spot of compound (5) disappears and a new spot of Rf0.59 of compound (4) is created on the top.
A spot of Rf0.37 appeared. Furthermore, compound (5) 50mg
(0.12mM) with 1ml of dichloroethane,
After stirring for 5 minutes, spots of compound (4) disappeared on LC (toluene: ethyl acetate 5:1).
Almost a single spot of Rf0.37 appeared. After filtering through diatomaceous earth, add about 100 ml of ethyl acetate, wash twice with saturated sodium bicarbonate solution and once with saturated saline, dry with MgSO ₄ , remove the solvent, and perform flash chromatography on 80 g of silica gel (toluene: 5 ml of ethyl acetate). :1)
1113 mg of syrupy substance (6) was isolated (71
%).

[Properties of compound (6)] Elemental analysis: C as C ₄₃ H ₅₄ O ₁₅ ; 66.19, H; 6.25 Actual value C; 66.31, H; 6.29 [α] ²⁰ _D +34.8° (C = 0.12, CHCl ₃ ) NMR: δH ( _CDCl3 ): 7.37-7.19 (20H, m, aromatic) 5.37 (1H, s, H-1b) 5.15 (1H,
H-2b) 5.04 (H-1, H-1a) 2.07-
1.96 (12H, m, Ac) Reference example 2 Compound (6) 800mg (0.91mM) in methanol 20ml
Add 5 ml of formic acid and 500 mg of 10% Pd-C to 60
After stirring overnight at °C, the Rf0.61 spot of the raw material disappeared on TLC (toluene:ethyl acetate 2:1), and a new spot appeared at the origin. This thing is
0 to 0 with TLC (chloroform:methanol 5:1)
It showed a multi-spot of 0.58. After removing the solvent,
Stirring for 30 minutes at room temperature in 1N triethylamine/methanol resulted in TLC (chloroform:methanol 5:
1) A single spot of Rf0.58 of compound (7) appeared on the surface. After removing the solvent, 20 ml of acetic anhydride:pyridine 1:2 mixed solution was added and stirred overnight. On TLC (toluene: ethyl acetate 1:1), the origin spot of the raw material disappeared and a new single spot of Rf0.37 was found. Appeared. After removing the solvent, dissolve in 100ml of ethyl acetate and dilute with 100ml of water.
After washing once with saturated saline and drying with _MgSO4 ,
After removing the solvent, it was isolated by flash chromatography using 50 g of silica gel (toluene: ethyl acetate 2:1) to obtain 550 mg of powdery substance (8) (89%) [Properties of compound (8)] Elemental analysis: C ₂₈ H ₃₈ O ₁₉ as C; 49.56 H; 5.60 Actual value C; 49.49 H; 5.68 [α] ²⁰ _D +27.8° (C = 0.4, CHCl ₃ ) NMR: δH (CDCl ₃ ): 6.11 (1H, d , 2.7Hz, H-1-
a) 2.14-2.00 (24H, m, Ac) Reference example 3 3 ml of 25% HBr/acetic acid in a 30 ml two-necked flask,
Add 0.1 ml of acetic anhydride, stir at room temperature for 30 minutes after purging with nitrogen, and add compound (8) dissolved in 3 ml of dichloromethane.
200 mg was injected. After stirring for 1 hour at room temperature, tlc
(Toluene: Ethyl acetate 1:1)
The Rf0.33 spot disappeared, and a new Rf0~0.19,
A multi-spot appeared at 0.51. After removing the solvent and azeotroping with toluene three times, TLC (toluene:ethyl acetate 1:1) showed a single spot with an Rf of 0.45.
180 mg of syrupy material (9) was isolated by flash chromatography on 5 g of silica gel (toluene:ethyl acetate 1:1). (85%) [Properties of compound (9)] [α] ²⁰ _D 48.7° (C = 0.4, CHCl ₃ ) Example 2 1.5 g of molecular sieves 5A powder and a rotor were placed in a 30 ml brown two-necked flask. 3 under reduced pressure at 180℃
The mixture was stirred for several days. After cooling to room temperature, dissolve in 10ml of toluene.
_150mg (0.58mM) of _AgOSO2CF3 was added and the solvent was removed. After nitrogen substitution, 120 mg (0.059 mM) of compound (3) was injected together with 10 ml of benzene, and the mixture was stirred at room temperature for 1 hour. Compound (9) 100 dissolved in 2 ml of benzene after cooling to 5°C
mg (0.14mM) and stirred for 30 minutes.
On TLC (toluene:ethyl acetate 1:1), both the spot of compound (3) with Rf0.29 and the spot of compound (9) with Rf0.39 almost disappeared, and undiscernible multi-spots with Rf0.04 to 0.13 were observed. has newly appeared. This thing is
on tlc (toluene:ethyl acetate 1:2)
Two spots of Rf0.76Rf0.61 are shown. Furthermore, 50 mg (0.07 mM) of compound (9) dissolved in 1 ml of benzene was injected dropwise and stirred for 30 minutes. On TLC (toluene: ethyl acetate 1:2), Rf0.52 and a multi-functional product, which was thought to be a hydrolyzate of compound (9), were detected. A spot appeared. After filtering with diatomaceous earth, add about 70ml of ethyl acetate and dilute with saturated sodium bicarbonate solution.
Washed once with saturated saline, dried over _MgSO4 , removed the solvent, isolated using Fractogel PVA2000,
mg of powdered material (10a) was obtained. (77%) [Properties of compound (10a)] Elemental analysis: C, 59.25 H, 5.95 as C ₁₅₂ H ₁₈₂ O ₆₇
Actual value C, 59.27 H, 5.98 [α] ²⁰ _D +49.0° (C = 0.2, CHCl ₃ ) NMR: δH: 7.30-7.18 (40H, m aromatic), 2.19-1.90 (63H, m 21×Ac) Example 3 Compound (10a) 100mg (0.032mM) at 0.05N
Dissolved in 5 ml of NaOMe/MeOH and stirred at room temperature for 2 hours. TLC (toluene: ethyl acetate 1:2)
Above, the raw material Rf0.52 spot disappeared, and a new spot appeared at the origin. This [compound (10b) was obtained by tlc (i-PrOH:AcOH: _H2O =4:
2:1), it appeared as a single spot with Rf0.73. After neutralizing with amberlist A-15, remove the solvent,
Dissolve in 2 ml of acetic acid and add 100 mg of 10% Pd-C to
Hydrogenation for 30 min at °C resulted in TLC (BuOH:
On AcOH:H ₂ O (1:1:1), the spot of Rf 0.96 of the raw material disappeared and a single spot of Rf 0.38 appeared. After passing through diatomaceous earth (Fc), remove the solvent and azeotropically distill with ethanol/methanol to obtain 40mg of powdered material (10c)
I got it. (83%) [Properties of compound (10c)] Elemental analysis: C ₅₄ H ₉₂ O ₄₆ , C as 4H ₂ O: 41.86,
H: 6.51 Actual value C: 41.66 H: 6.14 [α] ²⁰ _D +64.3° (C = 0.1, H ₂ O) NMR δH (60°C), 5.358 (0.7H, S, H-1aα) 5.284
(1H, H-1c), 5.160-5.138 (2H, H-
1h, H-1i), 5.105 (2H, H-1b, d)
5.058 (2H, H-1e, f), 5.024 (1H,
d, 1.7Hz, H-1g), 4.941 (0.3H, H-
1aβ) δc (D ₂ O 20℃): 102.44 (C-1e, C-1f, C
-1g, C-1h, C-1i) 100.71 (C-
1c), 98.49 (C-1b, C-1d) 92.80 (C
-1a) 78.82 (C-2 x 4, C-3 x 2)
66.39 (C-6×2) 61.37 (C-6×7).

Claims (1)

[Claims] 1. An oligomannoside represented by the following general formula. In the above formula, R is a hydrogen atom or an acetyl group,
R' is a hydrogen atom or benzyl group, Y is a hydrogen atom or (In the formula, R represents a hydrogen atom or an acetyl group)
shows. 2 formulas (In the formula, R′ represents a benzyl group) Compounds represented by and formula (In the formula, R is an acetyl group and X is a halogen atom.) A compound represented by (In the above formula, R is a hydrogen atom or an acetyl group,
R′ represents a hydrogen atom or a benzyl group) Method 3 for producing oligomannosides characterized by obtaining a compound represented by the formula (In the above formula, R represents an acetyl group and R' represents a benzyl group) (In the formula, R is an acetyl group and X is a halogen atom.) The compound represented by the formula is reacted, and if necessary, deacetylation and debenzylation are performed to form the general formula (In the above formula, R is an acetyl group or a hydrogen atom,
R′ represents a benzyl group or a hydrogen atom).