CN106674295A - Preparation method for 1-O-acetyl-3,4-di-O-benzyl-2,6-dideoxy-alpha-D-glucoside - Google Patents
Preparation method for 1-O-acetyl-3,4-di-O-benzyl-2,6-dideoxy-alpha-D-glucoside Download PDFInfo
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- CN106674295A CN106674295A CN201611152670.0A CN201611152670A CN106674295A CN 106674295 A CN106674295 A CN 106674295A CN 201611152670 A CN201611152670 A CN 201611152670A CN 106674295 A CN106674295 A CN 106674295A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07H—SUGARS; DERIVATIVES THEREOF; NUCLEOSIDES; NUCLEOTIDES; NUCLEIC ACIDS
- C07H13/00—Compounds containing saccharide radicals esterified by carbonic acid or derivatives thereof, or by organic acids, e.g. phosphonic acids
- C07H13/02—Compounds containing saccharide radicals esterified by carbonic acid or derivatives thereof, or by organic acids, e.g. phosphonic acids by carboxylic acids
- C07H13/04—Compounds containing saccharide radicals esterified by carbonic acid or derivatives thereof, or by organic acids, e.g. phosphonic acids by carboxylic acids having the esterifying carboxyl radicals attached to acyclic carbon atoms
- C07H13/06—Fatty acids
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07H—SUGARS; DERIVATIVES THEREOF; NUCLEOSIDES; NUCLEOTIDES; NUCLEIC ACIDS
- C07H1/00—Processes for the preparation of sugar derivatives
Abstract
The invention discloses a preparation method for 1-O-acetyl-3,4-di-O-benzyl-2, 6-dideoxy-alpha-D-glucoside. The preparation method is characterized by adopting a two-step method to synthesize 1-O-acetyl-3,4-di-O-benzyl-2,6-dideoxy-alpha-D-glucoside. The two-step method comprises the steps of dissolving 6-deoxy-D-glucal in N,N-dimethylformamide firstly, then adding sodium hydride and benzyl bromide to prepare 3,4-di-O-benzyl-6-dexoy-D-glucal, then dissolving 3,4-di-O-benzyl-6-dexoy-D-glucal in dichloromethane, adding acetic anhydride, acetic acid and hydrogen bromide acetum to conduct glycosylation to obtain 1-O-acetyl-3,4-di-O-benzyl-2,6-dideoxy-alpha-D-glucoside. Compared with the prior art, the preparation method for 1-O-acetyl-3,4-di-O-benzyl-2,6-dideoxy-alpha-D-glucoside has the advantages that the process is simple, the reagents used are all cheap and easily available, the production cost is low, the yield is high, the total yield can be improved by 60%, and high-toxic chemical reagents can be effectively avoided, so that the preparation method is relatively environmentally friendly, economical and efficient.
Description
Technical field
The present invention relates to technical field of organic synthesis, specifically a kind of to be used for pharmaceutical intermediate 1-O- acetyl group -3,
The preparation method of-O- benzyls -2,6- the dideoxies of 4- bis--alpha-D-glucose glycosides.
Background technology
2,6- dideoxies sugar is often found to be present in Angucycline antibiotic, and this kind of antibiotic is because have wide spectrum
Biological activity and receive significant attention, wherein, it is more that 2,6- bis--DDG structures are found, and it mainly passes through
C-/O- glycosidic bonds are connected with other groups.- O- benzyls -2,6- the dideoxies of 1-O- acetyl group -3,4- two-alpha-D-glucose glycosides is
A kind of donor that effectively can be used to prepare Angucycline antibiotic, is successfully used for vineomycin B2The conjunction of methyl ester
Into.
At present, 1-O- acetyl group -3,-O- benzyl -2 of 4- bis-, the synthesis of 6- dideoxies-alpha-D-glucose glycosides is with 1-O- pair
Methoxy-benzyl-β-D- 2-desoxy-D-altromethyloses are raw material, first the cis hydroxyl groups Jing two-step reaction of C-3 and C-4 positions are switched to into trans hydroxyl
The two hydroxyls are subsequently carried out benzyl protection by base, reuse ammonium ceric nitrate removing end group substituent group, and finally terminal hydroxyl is entered
Row acetylation obtains the-O- benzyls -2,6- dideoxies of 1-O- acetyl group -3,4- two-alpha-D-glucose glycosides (Qian Chen, Yashan
Zhong and George A.O’Doherty.Convergent de novo synthesis of vineomycinone B
2methyl ester[J].Chemical Communications,2013,49(60)：6806-6808).
The synthetic method of prior art, complicated process of preparation, production process is long, complex operation step, industrialization cost compared with
Height, five step in need is completed, and the products collection efficiency low selectivity of generation is poor, wherein ammonium ceric nitrate Deprotection and acetylization reaction
Poor selectivity, directly affects overall yield.And need to use Nitrodracylic acid, Lithium hydrate etc. in building-up process by force
Acid, the material of highly basic, due to ammonium ceric nitrate used in building-up process, can produce the waste water containing heavy metal ion cerium, be also easy to produce
Environmental pollution, has had a strong impact on 1-O- acetyl group -3,-O- benzyl -2 of 4- bis-, and 6- dideoxies-alpha-D-glucose glycosides is in the middle of medicine
The extensive application of body.
The content of the invention
The purpose of the present invention be for the deficiencies in the prior art and provide a kind of-O- benzyls of 1-O- acetyl group -3,4- two -
The preparation method of 2,6- dideoxies-alpha-D-glucose glycosides, adopts 6- DDGs alkene for Material synthesis 3 ,-O- the benzyls of 4- bis-
Base -6- DDG alkene, then prepares 1-O- acetyl group -3 by its glycosylation reaction, and-O- benzyl -2 of 4- bis-, 6- bis- takes off
Oxygen-alpha-D-glucose glycosides, process is simple, easy to operate, high income, low production cost, reaction condition is gentleer, it is to avoid high poison
The use of chemical raw material, is the new side of preparation of a kind of environmental protection and economical and efficient and very promising β-aromatic radical oxygen glycosides
Method.
Realizing the concrete technical scheme of the object of the invention is：A kind of-O- benzyls-the 2,6- two of 1-O- acetyl group -3,4- two take off
The preparation method of oxygen-alpha-D-glucose glycosides, is characterized in 6- DDGs alkene as Material synthesis 3 ,-O- the benzyls of 4- bis--
6- DDG alkene, then by its glycosylation reaction generation 1-O- acetyl group -3,-O- benzyl -2 of 4- bis-, 6- dideoxies -
Alpha-D-glucose glycosides, preparation is comprised the following steps：
The synthesis of-O- benzyl -6- DDG the alkene of a, 3,4- bis-
Under a nitrogen atmosphere, 6- DDG alkene is dissolved in DMF, is then sequentially added
Sodium hydride and benzyl bromine, carry out 2~5 hours synthetic reactions at a temperature of 0~70 DEG C, and-O- benzyl -6- deoxidation-the D- of 3,4- bis- are obtained
Fructus Vitis viniferae thin malt sugar, the 6- DDGs alkene is 1 with the molal volume ratio of sodium hydride, benzyl bromine and DMF：
2.0~7.0：2.0~5：10~30mL.
The synthesis of-O- benzyls -2,6- the dideoxies of b, 1-O- acetyl group -3,4- two-alpha-D-glucose glycosides
In dry conditions,-O- benzyl -6- DDG the alkene of 3,4- obtained in above-mentioned a steps bis- is dissolved in into two
In chloromethanes, the hydrogen bromide acetic acid solution that acetic anhydride, acetic acid and mass fraction are 25~40% is sequentially added under then stirring,
0.25~4 hour glycosylation reaction is carried out at a temperature of 0~50 DEG C, 1-O- acetyl group -3 are obtained,-O- benzyl -2 of 4- bis-, 6- bis- takes off
Oxygen-alpha-D-glucose the glycosides,-O- benzyls -6- DDGs alkene of 3, the 4- bis- is molten with acetic anhydride, acetic acid, bromination acetate hydrogen
The molal volume ratio of liquid and dichloromethane is 1：6~30：5~30：0.05~0.5；5~20mL.
Compared with prior art reaction scheme is greatly shortened the present invention, reaction condition milder, operates more easy, total product
Rate can bring up to 60% or so, and the used reagent of reaction is cheap and easy to get, and organic solvent and catalyst greatly reduce, raw
Producing cost substantially reduces, and efficiently avoid the use of strong acid and strong base reagent, free from environmental pollution, be a kind of more environmental protection and
Economical and efficient and very promising synthetic method.
Specific embodiment
The present invention prepares the-O- benzyl -2,6- dideoxy-α-D- Fructus Vitis viniferaes of 1-O- acetyl group -3,4- two using two-step synthesis method
Glucosides, the equation of its reaction is as follows：
Wherein：Structural formula I is 6- DDG alkene；Structure formula II is the-O- benzyl -6- deoxidation-D- Fructus Vitis viniferaes of 3,4- bis-
Thin malt sugar；Structure formula III is the-O- benzyls -2,6- dideoxies of 1-O- acetyl group -3,4- two-alpha-D-glucose glycosides；BnBr is benzyl bromine；
DMF is N,N-dimethylformamide.
The first step：6- DDG alkene is dissolved in DMF, hydrogenation is then sequentially added
Sodium, benzyl the bromine,-O- benzyl -6- DDG alkene of synthetically prepared 3,4- bis-；Second step：By prepare-O- the benzyls of 3,4- bis--
6- DDG alkene is dissolved in dichloromethane, and it is glycosylation to add acetic anhydride, acetic acid and hydrogen bromide acetic acid solution to carry out
Reaction, is obtained 1-O- acetyl group -3,-O- benzyl -2 of 4- bis-, 6- dideoxies-alpha-D-glucose glycosides.In first step reaction, 6- takes off
Oxygen-D-Glucose alkene is 2.0~7.0 with sodium hydride mol ratio, and is preferred with 3.0~5.0；6- DDGs alkene and benzyl
The mol ratio of bromine is 2.0~5.0, and is preferred with 2.5~3.5, and mol ratio is too low, and reaction slows down, and yield is substantially reduced, mol ratio
Too high then byproduct of reaction increases, and increases the difficulty of post processing, increases production cost, and reaction temperature is advisable with 0~70 DEG C, and with
15~40 DEG C are preferred.In second step reaction, mole body of 3,4- bis--O- benzyls -6- DDGs alkene and dichloromethane
Product and is preferred than being 5~20 with 7~12, and than too low, reactant concentration is too high, and byproduct of reaction increase, yield is bright for molal volume
Aobvious to reduce, than too high, material concentration is too low, and reaction slows down for molal volume, response time prolongation and yield is substantially reduced.Hydrogen bromide
The mass fraction of acetum is 25%~40%, and is preferred with 29%~33%, and mass fraction is too low, and reaction slows down, yield
Substantially reduce, mass fraction is too high, byproduct of reaction increases, increase the difficulty of post processing, increase production cost.- the O- of 3,4- bis-
Benzyl -6- DDGs alkene is 0.05~0.5 with the mol ratio of hydrogen bromide, and is preferred with 0.1~0.3, and mol ratio is too
Low, reaction slows down, and yield is substantially reduced, and mol ratio is too high, and byproduct of reaction increases, and increases production cost, and post processing can be because
Catalyst is made troubles.Reaction temperature is advisable for 0~50 DEG C, and is preferred with 15~40 DEG C.
Below will the present invention is further elaborated by specific embodiment：
Embodiment 1：
The synthesis of-O- benzyl -6- DDG the alkene of a, 3,4- bis-
Under nitrogen protection, 0.34g (2.6mmol) 6- DDG alkene is dissolved in into 5ml N, N- dimethyl methyls
Amide, is subsequently adding 0.13g (5.2mmol) NaH, Deca 0.6ml (8.9mmol) benzyl bromine after stirring 15min, at a temperature of 15 DEG C
Stirring 4.5 hours, reaction adds water after terminating and is quenched, and after dichloromethane extraction anhydrous sodium sulfate drying is used, and obtains light yellow after being spin-dried for
Syrup product 0.66g is the-O- benzyl -6- DDG alkene of 3,4- bis-, and its yield is 69%.
The synthesis of-O- benzyls -2,6- the dideoxies of b, 1-O- acetyl group -3,4- two-alpha-D-glucose glycosides
Under nitrogen protection,-O- benzyl -6- DDG the alkene of 250mg (0.8mmol) 3,4- bis- is dissolved in
10ml dichloromethane, is subsequently adding 0.4mL (4mmol) Ac2O and 0.9mL (16mmol) HOAc, after stirring 15min 1.5 μ L are added
40%HBr/HOAc, stirs 0.25h at a temperature of 25 DEG C, and reaction adds 20gNaOAc to be quenched, leaches synthetic with saturation after terminating
Sodium bicarbonate is washed, and Jing silicagel column elutions after being spin-dried for anhydrous sodium sulfate drying, obtains faint yellow syrup product 230mg for 1-O-
Acetyl group -3,-O- benzyl -2 of 4- bis-, 6- dideoxies-alpha-D-glucose glycosides, its yield is 78%, and what the silicagel column was adopted washes
De- agent is petroleum ether：Ethyl acetate=20: 1.
Above-mentioned products therefrom Jing is analyzed to identify as 1-O- acetyl group -3,-O- benzyl -2 of 4- bis-, 6- dideoxy-α-D- Fructus Vitis viniferaes
Glucosides, its test data is as follows：
1H NMR(500MHz,CDCl3) δ 7.36-7.33 (m, 2H), 7.30 (d, J=6.7Hz, 3H), 6.14 (d, J=
2.2Hz, 1H), 5.32-5.23 (m, 1H), 4.72 (d, J=11.2Hz, 1H), 4.68-4.64 (m, 1H), 3.92-3.85 (m,
1H), 3.23 (t, J=9.3Hz, 1H), 2.27 (ddd, J=13.4,5.2,1.5Hz, 1H), 2.09 (s, 3H), 2.01 (s, 3H),
1.81 (ddd, J=13.4,11.4,3.7Hz, 1H), 1.31 (d, J=6.2Hz, 3H).
Mass spectrum：HRMS(ESI):m/z Calculated for[M+Na]+C17H22O6Na 393.1672,found
393.1679。
Embodiment 2
The synthesis of-O- benzyl -6- DDG the alkene of a, 3,4- bis-
Under nitrogen protection, 1.0g (7.7mmol) 6- DDG alkene is dissolved in into 15ml N, N- dimethyl methyls
Amide, is subsequently adding 0.61g (27mmol) NaH, Deca 2.7ml (23.1mmol) benzyl bromine after stirring 15min, at a temperature of 25 DEG C
Stirring 3.5 hours, reaction adds water after terminating and is quenched, and after dichloromethane extraction anhydrous sodium sulfate drying is used, and obtains light yellow after being spin-dried for
Syrup product 1.89g is the-O- benzyl -6- DDG alkene of 3,4- bis-, and its yield is 79%.
The synthesis of-O- benzyls -2,6- the dideoxies of b, 1-O- acetyl group -3,4- two-alpha-D-glucose glycosides
Under nitrogen protection,-O- benzyl -6- DDG the alkene of 250mg (0.8mmol) 3,4- bis- is dissolved in
10ml dichloromethane, is subsequently adding 1.8mL (18mmol) Ac2O and 0.5mL (8mmol) HOAc, after stirring 15min 3.2 μ L are added
32%HBr/HOAc, stirs 2h at a temperature of 25 DEG C, and reaction adds 20gNaOAc to be quenched, leaches synthetic with unsaturated carbonate after terminating
Hydrogen sodium is washed, and Jing silicagel column elutions after being spin-dried for anhydrous sodium sulfate drying, obtains faint yellow syrup product 219mg for 1-O- acetyl
Base -3,-O- benzyl -2 of 4- bis-, 6- dideoxies-alpha-D-glucose glycosides, its yield is 74%.
Embodiment 3
The synthesis of-O- benzyl -6- DDG the alkene of a, 3,4- bis-
Under nitrogen protection, 2.0g (15.4mmol) 6- DDG alkene is dissolved in into 30ml N, N- dimethyl methyls
Amide, is subsequently adding 1.1g (46.2mmol) NaH, Deca 5.5ml (46.2mmol) benzyl bromine after stirring 15min, in 25 DEG C of temperature
Lower stirring 4 hours, reaction adds water after terminating and is quenched, and after dichloromethane extraction anhydrous sodium sulfate drying is used, and obtains light yellow after being spin-dried for
Syrup product 3.91g is the-O- benzyl -6- DDG alkene of 3,4- bis-, and its yield is 82%.
The synthesis of-O- benzyls -2,6- the dideoxies of b, 1-O- acetyl group -3,4- two-alpha-D-glucose glycosides
Under nitrogen protection,-O- benzyl -6- DDG the alkene of 250mg (0.8mmol) 3,4- bis- is dissolved in
10ml dichloromethane, is subsequently adding 2.4mL (24mmol) Ac2O and 1.4mL (24mmol) HOAc, after stirring 15min 3.5 μ are added
L 25%HBr/HOAc, stir 1h at a temperature of 40 DEG C, and reaction adds 20gNaOAc to be quenched, leaches synthetic with saturated carbon after terminating
Sour hydrogen sodium washing, and Jing silicagel column elutions after being spin-dried for anhydrous sodium sulfate drying, obtain faint yellow syrup product 216mg for 1-O- second
Acyl group -3,-O- benzyl -2 of 4- bis-, 6- dideoxies-alpha-D-glucose glycosides, its yield is 73%.
The various embodiments described above products therefrom after testing, analysis after can confirm that as pure target product.Above simply to this
Invention is further described, and is not used to limit this patent, all for equivalence enforcement of the present invention, is intended to be limited solely by the power of this patent
Within sharp claimed range.
Claims (1)
1. a kind of 1-O- acetyl group -3,4- two -O- benzyl -2,6- dideoxies -αThe preparation method of-D-Glucose glycosides, its feature
Be with 6- DDGs alkene as Material synthesis 3,4- bis--O- benzyl -6- DDG alkene, then by its glucosides
Change reaction and generate 1-O- acetyl group -3,4- two -O- benzyl -2,6- dideoxies -α- D-Glucose glycosides, preparation is comprised the following steps：
A, 3,4- bis--OThe synthesis of-benzyl -6- DDG alkene
Under a nitrogen atmosphere, 6- DDG alkene is dissolved in DMF, then sequentially adds hydrogenation
Sodium and benzyl bromine, carry out 2 ~ 5 hours synthetic reactions at a temperature of 0 ~ 70 DEG C, and prepared 3,4- bis--O- benzyl -6- DDGs
Alkene, the 6- DDGs alkene is 1 with the molal volume ratio of sodium hydride, benzyl bromine and DMF：2.0~
7.0：2.0~5：10~30mL；
b、1-O- acetyl group -3,4- two -O- benzyl -2,6- dideoxies -αThe synthesis of-D-Glucose glycosides
In dry conditions, by 3,4- bis- obtained in above-mentioned a steps-O- benzyl -6- DDG alkene is dissolved in dichloro
In methane, the hydrogen bromide acetic acid solution that acetic anhydride, acetic acid and mass fraction are 25 ~ 40% is sequentially added under then stirring, 0 ~ 50
0.25 ~ 4 hour glycosylation reaction is carried out at a temperature of DEG C, 1- is obtainedO- acetyl group -3,4- two -O- benzyl -2,6- dideoxies -α-
D-Glucose glycosides, 3, the 4- bis--O- benzyl -6- DDGs alkene and acetic anhydride, acetic acid, hydrogen bromide acetic acid solution and
The molal volume ratio of dichloromethane is 1：6~30：5~30：0.05~0.5；5~30mL .
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102180914A (en) * | 2011-04-06 | 2011-09-14 | 华东师范大学 | Preparation method of 2-deoxidizing-D-glucose |
| CN105007732A (en) * | 2012-12-31 | 2015-10-28 | 美国陶氏益农公司 | Macrocyclic picolinamides as fungicides |
| WO2015175695A1 (en) * | 2014-05-13 | 2015-11-19 | Debrabander Jef | Small molecule compounds selective against gram-negative bacterial infections |
-
2016
- 2016-12-14 CN CN201611152670.0A patent/CN106674295A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102180914A (en) * | 2011-04-06 | 2011-09-14 | 华东师范大学 | Preparation method of 2-deoxidizing-D-glucose |
| CN105007732A (en) * | 2012-12-31 | 2015-10-28 | 美国陶氏益农公司 | Macrocyclic picolinamides as fungicides |
| WO2015175695A1 (en) * | 2014-05-13 | 2015-11-19 | Debrabander Jef | Small molecule compounds selective against gram-negative bacterial infections |
Non-Patent Citations (2)
| Title |
|---|
| QIAN CHEN，等: "Convergent de novo synthesis of vineomycinone B2 methyl ester", 《CHEM. COMMUN.》 * |
| VÉRONIQUE BOLITT，等: "Direct Preparation of 2-Deoxy-D-glucopyranosides from Glucals without Ferrier Rearrangement", 《J. ORG. CHEM.》 * |
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