CN1291614A - Process for synthesizing saponin with 2,4-O-disubstituted glucosylose chain - Google Patents

Process for synthesizing saponin with 2,4-O-disubstituted glucosylose chain Download PDF

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CN1291614A
CN1291614A CN 00119867 CN00119867A CN1291614A CN 1291614 A CN1291614 A CN 1291614A CN 00119867 CN00119867 CN 00119867 CN 00119867 A CN00119867 A CN 00119867A CN 1291614 A CN1291614 A CN 1291614A
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mol ratio
saponin
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CN1163500C (en
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俞飚
惠永正
李兵
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Shanghai Institute of Organic Chemistry of CAS
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Abstract

The present invention relates to a process for synthesizing a saponin from easily available aglycone and monosaccharide. The structural formula of synthesized saponin is also disclosed.

Description

A kind of synthesizing has 2, and 4-O-two replaces the method for the saponin of glucosyl group sugar chains
The present invention relates to a kind of synthetic method of saponin, specifically a kind of 2,4-O-two replaces the synthetic method of the saponin of glucosyl group sugar chains, and this class saponin is the material with physiologically active.
Have 2, the saponin that 4-O-two replaces the glucosyl group sugar chain distributes very wide in plant, be effective ingredient (Saponins.K.Hostetamnn, A.Marston, the Cambridge University Psess:Cambridge of many herbal medicine, 1995) as 2, the Dioscin that the 4-O-rhamanopyranosyl replaces can separate from Paris polyphylla, Dioscorea nipponica Mak. Ningpo Yam Rhizome plant and obtains, and has cardiovascular, antitumor and antimycotic activity (K.Nakaro etc., Chem.Pharm.Bull.37,116-118,1989; C.D.Hufford etc., J.Nat.Prod., 51,94-98,1988, the Polyphyllin D that 2-O-sandlwood pyrans glycosyl 4-O-arbinofuranose replaces once separated from plants such as Paris polyphylla, have cardiovascular and antineoplastic activity (T.Namba etc., Planta medica, 55,501-506,1989; J.Zhou, Pure, Appl.Chem., 61,457-460,1989), from the plant Balanitin of West Africa, separate the Balanitin 7 that obtains and have anti-tumor activity (G.B.Pettit etc., J.Nat.Prod., 54,1491-1502,1991).But the saponin portioning in the plant often exists with the homology mixture of complexity, and a certain composition that separates wherein is very difficult, does not have the synthetic method to prepare these saponins so far.Therefore, to prepare the saponin with this class formation easily from the glucoside that is easy to get unit and monose be highly significant to the method for development chemosynthesis.
The purpose of this invention is to provide and a kind of synthesizing have 2, the method for the saponin of 4-O-two replacement glucosyl group sugar chains.
Method of the present invention is from glucoside unit and the monose that is easy to get, easy Synthetic 2, and two of 4-O-replaces the saponin of glucosyl group sugar chain, and this saponin has following structure and is:
Figure 0011986700041
R wherein 1=Chinese yam glucoside unit base, carry glucoside unit bases such as fruit glucoside unit base, luxuriant numb glucoside unit base, R 2=α-L-furans rhamanopyranosyl, R 3Glycosyls such as=α-L-rhamnopyranosyl, α-L-arabinofuranosyl, glucosyl group, xylosyl 3-xylosyl-glucosyl group.
Method of the present invention can be represented with following reaction formula:
Figure 0011986700042
In the method for the present invention; adopt efficient product 2 (the Yu Biao etc. that obtain of glucose and glucoside unit; Tetrahedron Letters; 39; 6511-6514; 1998) be raw material; at glucoside unit glucoside 3; 6 one steps go up trimethylammonium formyl radical (Piv) protecting group simultaneously and get compound 3; compound 3 obtains compound 4 or 5-1 with the α-L-furans rhamnosyl reaction of the protected different substituents of hydroxyl; compound 4 obtains compound 5 with the sugar reaction of the protected different substituents of hydroxyl, and compound 5 or 5-1 be acquisition 5 of deprotection base or 5-1 under alkaline condition.
Method of the present invention can further describe as follows:
Compound 2 reacts 0.5-5h with trimethylammonium formyl chloride (PivCl) and generates compound 3 in the time of polar solvent neutralization-5-50 ℃.Wherein compound 2 is 1 with the mol ratio of PivCl: 1-10, the recommendation ratio is 1: 2-5.
α-L-furans the rhamnosyl of compound 3 and the protected different substituents of hydroxyl
Figure 0011986700061
6 in the presence of promotor and molecular sieve and in the polar solvent ,-78-0 ℃ reaction 0.5-2h, obtain compound 4 or 5-1.Wherein compound 2 and 6 and the mol ratio of promotor be 1: 1-5: 0.2-2: 0-1, R 4=ethanoyl (Ac) or benzoyl (Bz), R 5=Cl 3C C=NH, C 2H 5S or halogen, halogen can be F, Cl, Br or I.
Compound 4 and R 7OR 5In the presence of promotor and molecular sieve and in the polar solvent ,-10-10 ℃ of reaction 0.5-2h obtains compound 5, and the mol ratio of compound 4, compound 7 promotor and molecular sieve is 1: 1-5: 0.2-2: 0-1.Described R 7OR 5Be that hydroxyl is by R such as acetyl or benzoyl bases 4Protection by Cl 3C C=NH, C 2H 5R such as S or halogen 5The sugar that replaces, R 7=
Figure 0011986700062
Figure 0011986700063
Halogen R wherein 4Or R 5Same as above.
In above-mentioned two steps and sugared direct reaction, described promotor can be BF 3(C 2H 5) 2The succimide (NIS) of O, silver trifluoromethanesulfonate (AgOTf), iodo or the mixture of above-mentioned substance.This is reflected at will help the carrying out that react under the anhydrous condition, as adding a spot of molecular sieve in the reactant.Improve speed of response and productive rate.This class reaction can also add weak base cancellation reaction, can add NH usually 3, (CH 3) 3N, (C 2H 5) 3Cancellation such as N reaction.
Compound 5 or 5-1 are in the presence of highly basic and in the polar solvent, generate compound 1 or 1-1 at 20-60 ℃ of reaction 1-10h, the mol ratio of described compound 5 or 5-1 and alkali is 1: 1-5, described alkali is the oxyhydroxide of monovalence metal, and described polar solvent is one or more water, methyl alcohol, ethanol, tetrahydrofuran (THF), the dissolving of acetonitrile isopolarity.R among product 5 and the 5-1 1, R 2, R 3As previously mentioned.
In the compound 5, work as R 3=R 2The time be compound 5-1.In other words, compound 5-1 can be synthetic with two kinds of methods, promptly earlier connects α-L-pyrans rhamnosyl simultaneously at 4 or 2,4 then at 2.
Method of the present invention provides a kind of 2 of physiologically active that has first, 4-O-two replaces the method for the saponin of glucosyl group sugar chain, adopt method of the present invention, synthetic Polyphyllin DDalanitin isoreactivity material easily not only, can also develop many new similar compounds, and raw material is easy to get, method is easy, compares with extracting method from natural phant, has industrial prospect.
The present invention will be helped to understand by following embodiment, but content of the present invention can not be limited.
Embodiment 13,6-two-O-trimethylammonium formyl radical-β-D-glucosyl group dioscin synthetic
In 1mmol dioscin base-β-D-Glucopyranose and 15ml pyridine or the toluene solution, in the time of-5-25 ℃, drip 1-5mmol trimethylammonium formyl radical chlorine, follow the tracks of reaction with thin-layer chromatography.Behind the reaction 1-4h,, use the saturated NaHCO of 10-20ml 1NHCl, 10ml successively with the dilution of 10ml vinyl acetic monomer 3The liquid washing.Organic phase is through anhydrous Na 2SO 4After the drying, dodge column chromatography for separation, be 8 with sherwood oil and vinyl acetic monomer volume ratio: the solution drip washing of 1-2, it is as follows finally to obtain colorless solid 0.44g product analysis result: [α] 1832.3 ° of (C0.87 CHCl of D 3) plate layer chromatography R f: 0.65 (3: 1 sherwood oil-vinyl acetic monomers) 1HNMR (300MHz, CDCl 3) δ: 5.35 (d, 1H, JJ2, H-6), 4.85 (t, 1H, J2,3, J3,4,9.06, H-3 '), 4.44-4.36 (m, 3H, H-1 ', H-16, H-6 ' is a), 4.25 (J5 ' 6 for dd, 1H ' b6.31, J6 ' ab ' b11.81, H-6 ' b), 3.58-3.58-3.32 (m, 6H, H-26, H-3, H-5 ', H-4 ', H-2 ') EIMS (m/z): 744,392,282 (base peaks), 139 ultimate analysis (C 43H 68O 101/2H 2O): calculated value C68.50 H9.22
Measured value C68.60 H9.30
Embodiment 2 2-O-(2,3,4-three-benzoyl-α-L-rhamanopyranosyl-3,6-two-O-trimethylammonium formyl radical
Synthesizing of-β-D-pyranoglucosyldioscin
The product of embodiment 1 The silver trifluoromethanesulfonate mol ratio is 1: 2-5: during 1-5, at CH 2Cl 2Or toluene solvant neutralization-20-0 ℃ of time reaction 1-2h, add 0.5ml triethylamine collection and go out, filter and concentrate, obtain white solid product, productive rate 60.4% through silicon amine column chromatography (30: 1, the toluene vinyl acetic monomer).The product analysis result is as follows: [α] 18D43.3 ° of (C1.14, CHCl 3) plate layer chromatography, Rf:0.41 (10: 1 toluene-ethyl acetates) 1HNMR (300MHz, CDCl 3) δ: 8.06-7.23 (m, 15H), 5.77 (d, J2 " 3 " J3 " 4 " 3.3Hz, H-3 "); 5.67-5.60 (m, 2H, H-2 ", H-4 "), 5.44 (brd; 1H, H-6), 5.24 (s, 1H; H-1 "), 1.16 (t, J2 ' 3 ' J3 ' 4 ' 9.23Hz, H-3 '), (4.82-4.77 m, 1H, H5 "), 4.68 (d; J1 ' 2 ' 7.7Hz, H-1 '), 4.44-4.41 (m, 2H; H-16, H-4 '), 4.28 (dd, J5 ' 6 ' a 6.6Hz; J6 ' ab ' b 11.9Hz, H-6 ' a), 4.14-4.11 (m, 1H; H-6 ' b), 3.85 (t, J1 ' 2 ' 7.95Hz, J2 ' 3 ' 8.99Hz; 1H, H-2 '), 3.67-3.59 (m, 2H, H-5 ', H-3), 3.50-3.39 (m, 2H, H-26) ESIMS (m/z): 1226,761,301 ((base peaks)), 149 ultimate analysis C 70H 90O 17: calculated value C69.86 H7.54
Measured value C69.64 H7.84
Embodiment 3 4-O-(three-ethanoyl-α-L-arabinose base)-2-O-(2,3,4 ,-three-O-benzoyl-α-L-rhamanopyranosyl)-3,6-two-trimethylammonium formyl radical-β-D-pyranoglucosyldioscin synthetic
The product of embodiment 2, With accelerant B F 3Et 2The mol ratio of O is 1: 2-6: during 0.2-1.5, at exsiccant CH 2Cl 2Stirring reaction 0.5-2h in the solvent filters, and concentrates.Enriched material separates with silica gel column chromatography, and the sherwood oil-vinyl acetic monomer that adopted 5: 1 is a leacheate, gets colorless solid after concentrating, productive rate 86%, and the product analysis result is as follows: [α] 14D 11.7 ° of (C1.17, CHCl 3) plate layer chromatography, Rf:0.56 (2: 1 sherwood oil-vinyl acetic monomers) 1HNMR (300MHz, CDCl 3) δ: 8.05-7.77 (m, 15H), 5.76 (dd, J2 ' 3 ' J3 ' 43.2Hz, 1H, H-3 '), 5.63-5.60 (m, 2H, H-2 ", H-4 "), 5.03 (s, 1H, H-1 "), 4.97 (dd, J3 4 , 3 , 2 1.5Hz; 1H, H-3 ), 4.70-4.68 (m, 2H); 4.5 (dd, J5 ' 6 ' a 1.8Hz, J6 ' a6 ' b 11.9Hz; 1H, H-6 ' a), 4.69-4.40 (m; 1H), 4.34-4.29 (m, 2H); 4.25-4.11 (m, 3H), 3.85-3.79 (m, 2H) ESIMS (m/z): 1484,743,442 (base peak) ultimate analysis C 81H 104O 24: calculated value C66.56 H7.17
Measured value C66.58 H7.23 embodiment 4 α-L-rhamanopyranosyl-(1-2)-[(I claps glycosyl α-L-)-(1-4)]-β-D-pyrans
Synthesizing of grape glycosyl dioscin (Polyphllin D)
The product of embodiment 3, the mol ratio of 1 valency metal hydroxides is 1: during 1-3, in one or more the polar solvent of 1-5ml at water, methyl alcohol, tetrahydrofuran (THF), acetonitrile and 20-60 ℃ of reaction 4-15h, with Dowes-732 (H +Type) neutralization is filtered and is concentrated.Enriched material separates with silica gel column chromatography, adopts 5: 1 CH 2Cl 2CH 3The drip washing of OH solution, concentrated back obtain Polyphllin D with 89% productive rate.Analytical results is as follows:
[α] 21D 113.6 ° of (C0.53, CH 3OH) plate layer chromatography, Rf:O.37 (5: 1CH 2Cl 2: CH 3OH) 1HNMR (300MHz, C 5D 5N) δ: 6.08 (s, 1H, H-1 "), 5.72 (s, 1H; H-1 ), 5.09 (d, 1H, J4.67Hz, H-6); 4.76-4.65 (m, 4H, H-1 ', H-2 ', H-4 '; H-2 ), 4.58 (d, 1H, J1.92, H-2 ); 4.40 (dd, 1H, H2 " 3 ", J3 " and 4 " 4.34, H-3 "), 4.32 (m, H-16), 4.18-3.92 (m-9H), 3.68 (m, 1H, H-3), 3.55 (m, 1H, H-5 "), 3.39-3.29 (m; 2H, H-26), 1.56 (d, J-6.31, H-6 "), 0.93 (d, 3H, J6.9), 0.84 (s, 3H), 0.62 (s, 3H), 0.48 (d, 3H, J4.95). 13C NMR (150MHz, C 5H 5D), δ: 140.78,121.79,109.24,101.88,100.15,86.71,82.67,81.11,78.12,77.90,77.70,77.42,77.04,76.72,74.13,72.80,72.47,69,48,66.86,62.91,62.50,61.41,56.63,50.30,41.98,40.46,39.86,38.90,37.49,37.14,32.30,31.83,31.69,30.60,30.16,29.98,29.26,21.10,19.40,18.65,17.30,16.33,15.03
Embodiment 5
Embodiment 2 described methods adopt different compounds 6 and promotor and compound 3 to generate in different mol ratio and reaction
Figure 0011986700091
The results are shown in following table: Annotate: α-L-Rha is α-L-furans rhamanopyranosyl
Embodiment 6
1mmol, NaOH 2-3mmol, in the mixed solvent of 10ml water, 10ml methyl alcohol and 10ml tetrahydrofuran (THF) and react 5h under the room temperature, aftertreatment is with embodiment 7, obtains with the productive rate of 80-91%
Figure 0011986700103
R wherein 1, R 2, R 4As previously mentioned
Figure 0011986700104
Or
Figure 0011986700105
Different R 3The result is as follows: product
Figure 0011986700106
The time, productive rate 86%.
13C NMR (75MHz, C 5D 5N); δ 108.91,105.94, and 102,20,101.45,99.62,86.98,81.14,80.76,77.74,77.80,72.26,76.95,75.91,74.96.73.76,73.64,72.41,72.08,70.56,69.12,68.68,67.04,66.52,62.55,61.38,61.14,56.28,49.95,45.35,41.63,40.12,39.51,39.48,38.58,37.15,36.78,31.96,31.88,31.49,31.34,30.25,29.80,28.93,20.76,1906,18.30,16.97,15.99,14.68. 1HNMR (300MHz, C 5D 5N); δ 6.25 (brs, 1H, H-1 "), 5.61 (t; 1H, J7.0), 5.37 (d, 1H; J3.7, H-6), 2.08,2.07; 2.05,1.99,1.94 (eachs, each 3H); 1.62,1.24 (each s, tach 3H), 1.131d; 3H, J6.1), 1.05 (s, 9H) .ESIMS:C 50H 80O 211017[M+1], 1016[M] product The time, productive rate 89.5% 1HNMR (300MHz, C 5D 5N); δ 6.38 (brs, 1H, H-1 ), 5.83 (brs., 1H, H-1 "), 5.31 (brd, 1H, H-6), 5.00-4.85 (m; 3H, H-1 ', H-2 ', H-4 '), 4.81 (brs; 1H), 4.66 (brs, 1H), 4.61 (dd, 1H; J3,4,9.3), 4.57-4.50 (m, 2H); 4.40-4.3.0 (m, 3H), 4.20 (m, 3H), 4.09 (dd; 1H, H-6 ' a), 3.87 (m-1H, H-3), 3.63 (m, 1H), 3.57 (m, 1H, H-26a), 3.50 (t, 1H, H-26b), 2.79 (dd, 1H), 2.71 (t, 1H), 1.76 (d, 3H), 1.62 (d, 3H), 1.13 (d, 3H), 1.04 (s, 3H), 0.82 (s, 3H), 0.69 (d, 3H). 13CNMR (75MHz, C 5D 5N); δ 214.12,109.44, and 103.09,102.23,100.45,81.28,78.70,78.22,78.15,77.95,77.14,74.32,74.13,73.02,72.94,72.75,70.60,69.72,67.04,63.06,61.44,56.80,50.46,42.14,45.2,40.63,40.02,39.15,3908,37.67,37.32,32.48,32.40,32.00,31.85,30.78,30.34,29.45,21.28,19.59,18.85,18.70,17.51,16.52,15.23.FABMS (m/z): C 45H 72O 7: 870[M+2], 868[M]

Claims (4)

1. one kind has 2, and 4-O-two replaces the synthetic method of the saponin of glucosyl group sugar chain, and this saponin has following structural formula R wherein 1=yam glycoside base, carry fruit glucoside base, luxuriant numb glucoside base, R 2=α-L-furans rhamanopyranosyl, R 3=α-L-furans rhamanopyranosyl, α-L-arabinofuranosyl, glucosyl group, xylosyl or 3-xylosyl glucosyl group is characterized in that with following method synthetic:
The mol ratio of trimethylammonium formyl chloride be 1: during 1-10, under polar solvent neutralization-5-50 ℃ temperature of reaction, react 0.5-5h, generate 3,6-two-O-trimethylammonium formyl radical-β-D-glucosyl group saponin.
(2) 3,6-two-O-trimethylammonium formyl radical-β-D-glucosyl group saponin,
Figure 0011986700023
Promotor and molecular sieve mol ratio are 1: 1-5: 0.2-5: during 0-1, reaction 0.5-2h generates in the time of polar solvent neutralization-78-0 ℃
Figure 0011986700025
The mol ratio of promotor molecular sieve is 1: 1-5: 0.2-2: during 0-1, polar solvent and-10-10 ℃ reaction 0.5-2h, synthetic
Figure 0011986700027
The mol ratio of monovalence metal hydroxides is 1: react 1-10h during 1-5 under polarity dissolving and 20-60 ℃ of temperature, generate
Figure 0011986700028
Figure 0011986700031
The oxyhydroxide mol ratio of monovalence metal is 1: during 1-5, react 1-10h in polar solvent He under 20-60 ℃ of temperature, generate
Figure 0011986700032
The oxyhydroxide mol ratio of monovalence metal is 1: during 1-5, react 1-10h in polar solvent He under 20-60 ℃ of temperature, generate
Figure 0011986700034
R wherein 1, R 2, R 3As previously mentioned, R 4=acetyl or benzoyl base, R 5=Cl 3C C=NH, C 2H 5S or halogen,
Figure 0011986700036
Described promotor is BF 3-(C 2H 5) 2O, silver trifluoromethanesulfonate, sulphur are for succimide, or the mixture of silver trifluoromethanesulfonate and iodo succimide.
2. a synthetic method as claimed in claim 1 is characterized in that in the described method (1)
Figure 0011986700037
With the mol ratio of trimethylammonium formyl chloride be 1: 2-5.
3. a synthetic method as claimed in claim 1 when it is characterized in that reaction finishes in described method (2) and (3), adds weak base cancellation reaction, and described weak base is NH 3, (CH 3) N or (C 2H 5) 3N.
4. a synthetic method as claimed in claim 1 is characterized in that the polar solvent described in described method (4) and (5) is water, methyl alcohol, ethanol, tetrahydrofuran (THF) or acetonitrile.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101792524B (en) * 2010-02-05 2012-08-29 中国科学院上海有机化学研究所 Glycosyl polyethers, preparation method thereof and use thereof
CN110479184A (en) * 2019-08-05 2019-11-22 华侨大学 A kind of agar glycosyl emulsifier and its preparation method and application

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101792524B (en) * 2010-02-05 2012-08-29 中国科学院上海有机化学研究所 Glycosyl polyethers, preparation method thereof and use thereof
CN110479184A (en) * 2019-08-05 2019-11-22 华侨大学 A kind of agar glycosyl emulsifier and its preparation method and application
CN110479184B (en) * 2019-08-05 2021-09-07 华侨大学 Agarose-based emulsifier and preparation method and application thereof

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