Method for producing curculigoside glycoside b

Abstract

FIELD: medicine; pharmacology.SUBSTANCE: method for producing the glycoside curculigoside B. The method is characterized by the fact that by reacting hydroquinone with benzoyl chloride, monobenzoylhydroquinone (2) is obtained, the interaction of which with urotropine in the presence of trifluoroacetic acid and then with silver oxide (I) and acetobromoglucose produces 5-(benzoyloxy)-2-[(2,3,4,6-tetra-O-acetyl-β-D-gluco-pyranosyl)oxy]benzaldehyde (4). Next, compound (4) is reacted with sodium methylate in methanol, the product is acetylated with acetic anhydride and reduced with sodium borohydride to obtain 5-(acetyloxy)-2-(hydroxymethyl)phenyl-(2,3,4,6-tetra-O-acetyl)-β-D-glucopyranoside (7). Tetrabromomethane and triphenylphosphine are added to compound (7), then potassium carbonate and 2-hydroxy-6-methoxybenzoic acid are added to the resulting intermediate product, obtaining pentaacetate of the glycoside curculigoside B, which, in turn, is treated with hydrochloric acid in methanol, neutralized with a cation exchange resin to obtain curculigoside B.EFFECT: creation of a method for obtaining the target product.1 cl, 6 dwg, 1 ex

Description

[0001] The invention relates to organic chemistry, namely to a method for producing the glycoside curculigoside B, which can be used in medicine and pharmacology.

[0002] A known method for obtaining the glycoside curculigoside B by extraction from plants was selected as a prototype. According to the method, 5 kg of dry root powder from the plant Curculigo orchioides is extracted three times in an ultrasonic bath using hot methanol (50°C) [Vuong NQ et al. Two new phenolic glucosides from Curculigo orchioides and their cytotoxic effects / / Phytochemistry Letters. - 2024. - Vol. 60. - Pp. 113-116]. The resulting alcoholic extract is concentrated under reduced pressure and diluted in 1.5 liters of water. The resulting aqueous suspension is extracted with two solvents: n-hexane and ethyl acetate. The aqueous fraction (ACO3) was subjected to chromatographic separation on a Diaion HP-20 column eluting with water (2 L) to remove polar components and then eluted with MeOH:H2O solution in the ratios of 1:1, 3:1, respectively, and pure MeOH (0.8 L each) to obtain three fractions: ACO3A (54.0 grams), ACO3B (24.5 grams), and ACO3C (2.5 grams), respectively.ACO3A was separated on a silica gel column eluting with CH2Cl2:MeOH (20:1, 10:1, 5:1, 2.5:1, 1:1, v:v) to give five fractions: ACO3A1 (4.9 grams), ACO3A2 (7.0 grams), ACO3A3 (6.5 grams), ACO3A4 (4.8 grams), and ACO3A5 (5.0 grams). Of these, ACO3A1 (4.9 grams) was subjected to silica gel column chromatography and elution with a mixture of CH2Cl2:acetone:H2O (1:1.5:0.1, v:v:v) to obtain six fractions: ACO3A1A (0.7 grams), ACO3A1B (0.7 grams), ACO3A1C (0.6 grams), ACO3A1D (0.6 grams), ACO3A1A (0.5 grams) and ACO3A1F (0.6 grams). Fraction ACO3A1D was then subjected to RP-18 column chromatography eluting with a mixture of MeOH:H2O (1:1.5, v:v). Further high performance liquid chromatography using a mobile phase of 25% acetonitrile in water yields curculigoside B in an amount of 6.5 mg.

[0003] However, the known method is characterized by a low yield of the final product of 0.00013% and a high consumption of plant materials, which are currently on the verge of extinction.

[0004] The technical result of the proposed invention is the creation of a method for producing the glycoside curculigoside B.

[0005] According to the invention, 0.103 mol of benzoyl chloride is added dropwise to 0.206 mol of hydroquinone dissolved in a 10% sodium hydroxide solution and cooled in an ice bath, stirred, and filtered. The precipitate is then recrystallized from toluene to obtain monobenzoylhydroquinone, 12.6 mmol of which is mixed with 25.2 mmol of urotropine and 30 ml of trifluoroacetic acid and stirred at 77°C for 5 hours. Then 0.5 ml of hydrochloric acid is added, the mixture is stirred, and neutralized with an aqueous solution of sodium bicarbonate. The resulting solution is extracted with ethyl acetate, dried over magnesium sulfate, filtered, and evaporated on a rotary evaporator. The resulting extract is purified by column chromatography and mixed with 5.37 mmol of silver (I) oxide and 4.128 mmol of acetobromoglucose. Quinoline is then added to the reaction mixture, stirred with a glass rod for 2 hours, diluted with methylene chloride, and passed through a Schott filter.The resulting filtrate is washed successively with sodium hydroxide solution and sulfuric acid, dried over magnesium sulfate, filtered, evaporated on a rotary evaporator, and purified by column chromatography. Next, 10.44 mmol of sodium methoxide is added, the mixture is dissolved in methanol, and stirred. The reaction mixture is then neutralized with a cation exchange resin, filtered, evaporated on a rotary evaporator, and purified by column chromatography. The reaction product is mixed with 3.93 mmol of sodium acetate and 26.2 mmol of acetic anhydride. The reaction mixture is stirred at 90°C for 8 hours and at room temperature for 16 hours, extracted with ethyl acetate, dried over magnesium sulfate, filtered, evaporated on a rotary evaporator, and dissolved in 10 ml of ethyl acetate. Next, add 10 ml of distilled water and 3.21 mmol of sodium tetraborate, stir for 12 hours, extract with ethyl acetate and dry with magnesium sulfate.The reaction mixture is then filtered and evaporated on a rotary evaporator to obtain 5-(acetyloxy)-2-(hydroxymethyl)phenyl-(2,3,4,6-tetra-O-acetyl)-β-D-glucopyranoside, 0.195 mmol of which is dried under reduced pressure in a flask supplied with argon and dissolved in dried ethyl acetate. After this, a solution of 0.312 mmol of tetrabromomethane in dried ethyl acetate is added, the mixture is cooled in an ice bath and a solution of 0.331 mmol of triphenylphosphine in dried ethyl acetate is added, the mixture is stirred, evaporated on a rotary evaporator and dried for 1 hour under reduced pressure. The flask containing the reaction mixture is filled with argon, 0.232 mmol of potassium carbonate and 0.226 mmol of 2-methoxy-5-hydroxybenzoic acid are added. N,N-Dimethylformamide (DMF) is added to the flask, the mixture is stirred, evaporated on a rotary evaporator, and purified by column chromatography to obtain curculigoside B glycoside pentaacetate, 0.142 mmol of which is dissolved in 1 ml of dichloromethane (DCM).Then 3 ml of methanol and 0.142 ml of hydrochloric acid are added, mixed, neutralized with a cation exchange resin, filtered, evaporated on a rotary evaporator and purified by column chromatography to obtain curculigoside B.

[0006] Unlike the prototype, no plant materials are used to produce curculigoside B. According to the proposed method, the overall yield of curculigoside B is 2.3%.

[0007] Fig. 1 shows a reaction scheme for obtaining the glycoside curculigoside B according to the invention.

[0008] Fig. 2 shows the nuclear magnetic resonance (hereinafter referred to as NMR) spectrum of proton nuclei 1 H (400 MHz, CD3OD) glycoside curculigoside B.

[0009] Fig. 3 shows the NMR spectrum of carbon nuclei 13 C (101 MHz, CD3OD) glycoside curculigoside B.

[0010] Fig. 4 shows the spectrum of the glycoside curculigoside B obtained by the method of homonuclear correlation (COSY) NMR spectroscopy.

[0011] Fig. 5 shows the spectrum of the glycoside curculigoside B obtained by the method of heteronuclear single-quantum correlation (HSQC) NMR spectroscopy.

[0012] Fig. 6 shows the spectrum of the glycoside curculigoside B obtained by the heteronuclear multi-connected correlation (HMBC) NMR spectroscopy method.

[0013] The invention is illustrated by an example in which 22.76 grams of hydroquinone are placed in a 250 ml flask and 41.5 ml of a 10% aqueous sodium hydroxide solution are added (Fig. 1). The resulting solution, placed in an ice bath and cooled to 0 ºC, is then dripped with 12 ml of benzoyl chloride using a dropping funnel over the course of 2 hours. When 6 ml of benzoyl chloride enters the reaction mixture, it thickens, so it is diluted with 41.5 ml of water and benzoyl chloride is continued to be added dropwise. After the dropwise addition is complete, the resulting mixture is removed from the ice bath and left to stir on a magnetic stirrer at room temperature for 20 minutes. The reaction mixture is filtered using a Bunsen flask and a Buchner funnel, and the resulting precipitate is washed with 60 ml of water. The precipitate is dissolved in 100 ml of toluene, brought to a boil and stirred with a glass rod until the precipitate is dissolved.The hot solution is cooled in a freezer at -19°C until the product crystallizes, filtered using a Bunsen flask and a Buchner funnel, and washed with 20 ml of toluene. This yields 2.8 grams of monoacetylhydroquinone. The products are analyzed using nuclear magnetic resonance (NMR). 1 H (400.13 MHz) and 13 C (101 MHz). NMR analysis results for monoacetylhydroquinone (2, Fig. 1) 1 H (400.13 MHz) ((CDCl3, 400 MHz) δ 6.9 (d, J = 8.9 Hz, 2H, Н-2, Н-6), 7.1 (d, J = 8.9 Hz, 2H, Н-3, Н-5), 7.5 (t, J = 7.8 Hz, 2H, Н-10, Н-12), 7.7 (t, J = 7.4 Hz, 1H, Н-11), 8.2 (d, J = 7.2 Hz, 2H, Н-9, Н-13)) and 13C (101 MHz) ((CDCl3, 101 MHz) δ 116.2 (C-2, C-6), 122.8 (C-3, C-5), 128.7 (C-10, C-12), 129.7 (C-8), 130.3 (C-9, C-13), 133.8 (C-11), 144.5 (C-4), 153.5 (C-1), 165.9 (C-7)) coincide with the literature data from the article [Belyanin, ML First total chemical synthesis of natural acyl derivatives of some phenolglycosides of the family Salicaceae / ML Belyanin, EV Stepanova, VD Ogorodnikov / / Carbohydrate research. – 2012. – 363. – P. 66-72], which are subsequently also used to determine known reaction products.

[0014] Next, 2.7 grams of monobenzoylhydroquinone and 3.53 grams of urotropine are placed in a 100 ml round-bottomed flask, and 30 ml of trifluoroacetic acid are added. The reaction proceeds under reflux with constant stirring on a magnetic stirrer and heating to 77 ºC for 5 hours. Then, the heating is turned off. When the flask temperature drops to room temperature, 0.5 ml of 33% hydrochloric acid solution is added and stirring is continued for 5 minutes. The pH of the solution is neutralized with sodium bicarbonate to 7, and the resulting mixture is extracted with ethyl acetate (three times with 120 ml of each). The mixture is separated using a separatory funnel. The three phases of ethyl acetate are combined, dried with magnesium sulfate by adding it to the combined ethyl acetate until a dense precipitate is formed, filtered through cotton wool placed in a glass funnel, and the filtrate is concentrated on a vacuum rotary evaporator.The resulting concentrate is purified using column chromatography, using hexane and ethyl acetate in a ratio of 5:1 as the eluent, resulting in 2-hydroxy-5-benzoyloxybenzaldehyde (3, Fig. 1) in an amount of 1.26 grams, which is analyzed by the method. 1 H NMR ((CDCl3, 400 MHz) δ 7.1 (d, J = 8.9 Hz, 1H, H-6), 7.4 (dd, J = 9.0, 2.9 Hz, 1H, H-5), 7.47 (d, J = 2.9 Hz, 1H, H-3), 7.53 (t, J = 7.8 Hz, 2H, H-10, H-12), 7.7 (t, J = 7.5 Hz, 1H, H-11), 8.2 (d, J = 7.1 Hz, 2H, H-9, H-13), 9.9 (s, 1H, COH), 11.0 (s, 1H, OH)) and by the method 13 C NMR ((CDCl3, 101 MHz) δ 119.0 (C-2), 120.4 (C-6), 125.7 (C-3), 128.8 (C-10, C-12), 129.2 (C-5), 130.3 (C-9, C-13), 131.0 (C-8), 134.1 (S-11), 143.4 (S-4), 159.5 (S-1), 165.4 (S-7), 195.9 (SON)).

[0015] Next, 1 gram of the previously obtained 2-hydroxy-5-benzoyloxybenzaldehyde, 1.243 grams of silver (I) oxide (Ag2O), and 2.206 grams of acetobromoglucose are placed in a 100 ml beaker. Then 4.4 ml of quinolyl are poured into the same beaker. The resulting solution is stirred with a glass rod at room temperature for 2 hours. Then the reaction mixture is diluted with 40 ml of methylene chloride. The resulting suspension is filtered from silver oxide through a Schott filter with a pore size of 16. The silver oxide remaining on the filter is washed with 50 ml of methylene chloride to obtain the first filtrate. The resulting first filtrate is washed three times with 70 ml of a 10 wt.% sodium hydroxide solution to obtain the second filtrate. The resulting second filtrate is washed three times with 50 ml of a 5% sulfuric acid solution to obtain a third filtrate. Magnesium sulfate is added to the third filtrate to remove residual water.Next, the magnesium sulfate is filtered through a cotton filter, and the resulting fourth filtrate is concentrated using a rotary evaporator. The resulting concentrate is purified using column chromatography, using a petroleum ether-ethyl acetate mixture in a ratio of 5:1 to 1:1 as the eluent. The resulting purified product is analyzed using [unclear]. 1 H NMR ((CDCl3, 400 MHz) δ 2.05, 2.06, 2.08, 2.09 (4×s, 12H, 4×COCH3), 3.9 (ddd, J = 10.0, 5.3, 2.4 Hz, 1H, H-5 Glu), 4.2 (dd, J = 12.4, 2.4 Hz, 1H, H-6b Glu), 4.31 (dd, J = 12.4, 5.3 Hz, 1H, H-6a Glu), 5.15 – 5.25 (m, 2H, H-1 Glu, H-4 Glu), 5.28 – 5.43 (m, 2H, H-2 Glu, H-3 Glu), 7.2 (d, J = 8.9 Hz, 1H, Н-6), 7.4 (dd, J = 8.9, 3.0 Hz, 1H, Н-5), 7.5 (t, J = 7.8 Hz, 2H, Н-10, Н-12), 7.6 (d, J = 7.4 Hz, 1H, Н-11), 7.7 (d, J = 2.9 Hz, 1H, Н-3), 8.2 (d, J = 7.1 Hz, 2H, Н-9, Н-13), 10.3 (s, 1H, СОН)) and 13C NMR ((CDCl3, 101 MHz) δ 20.21 – 21.45 (4×C, COCH3), 61.9 (C-6 Glu), 68.2 (C-4 Glu), 71.0 (C-2 Glu), 72.43, 72.52 (C-3 Glu, C-5 Glu), 99.7 (C-1 Glu), 117.8 (C-6), 121.2 (C-5), 127.3 (C-2), 128.8 (C-10, C12), 129.0 (C-8), 129.2 (C-9), 130.4 (C-13), 134.1 (C-11), 146.8 (C-4), 156.4 (C-1), 165.2 (C-7), 169.3, 169.5, 170.3, 170.6 (4×C-COCH3), 188.3 (C-COH)) and determined that 5-(benzoyloxy)-2-[(2,3,4,6-tetra-O-acetyl-β-D-gluco-pyranosyl)oxy]benzaldehyde (4, Fig. 1) was obtained in an amount of 1.9 grams.

[0016] Previously obtained 5-(benzoyloxy)-2-[(2,3,4,6-tetra-O-acetyl-β-D-gluco-pyranosyl)oxy]benzaldehyde in an amount of 1.5 grams and 0.55 grams of sodium methoxide are placed in a 250 ml flask and dissolved in 40 ml of methanol. The reaction mixture is stirred using a magnetic stirrer at room temperature for 4.5 hours, then neutralized with a cation exchange resin to a pH of 7, which is adjusted using indicator paper, then filtered to remove the cation exchange resin and the resulting filtrate is concentrated at a pressure of 337 mbar at a bath temperature of 40 °C on a vacuum rotary evaporator. The resulting concentrate is purified using column chromatography. A mixture of chloroform and methanol in a ratio of 14:1 to 5:1, respectively, is used as an eluent. The resulting purified product is analyzed using 1 H NMR ((CD3OD, 400 MHz) δ 3.35 (s, 1H, PhO H), 3.38 – 3.55 (m, 4H, H-2 Glu, H-3 Glu, H-4 Glu, H-5 Glu), 3.7 (dd, J = 12.2, 4.0 Hz, 1H, H-6b Glu), 3.9 (d, J = 12.0 Hz, 1H, H-6a Glu), 4.9 (d, J = 7.3 Hz, 1H, H-1 Glu), 7.05 (dd, J = 9.0, 3.2 Hz, 1H, H-4), 7.14 (d, J = 3.2 Hz, 1H, H-6), 7.3 (d, J = 8.9 Hz, 1H, H-3), 10.4 (s, 1H, COH)) and 13 C NMR ((CD3OD, 101 MHz) δ 62.4 (C-6 Glu), 71.2, 74.9, 77.9, 78.2 (C-2 Glu, C-3 Glu, C-4 Glu, C-5 Glu), 103.8 (C-1 Glu), 113.1 (C-6), 120.4 (C-3), 124.4 (C-4), 128.2 (C-5), 154.2 (C-2), 155.0 (C-1), 192.1 (C-COH).) and HSQC NMR, and determined that 5-(hydroxy)-2-[(β-D-gluco-pyranosyl)oxy]benzaldehyde (5, Fig. 1) was obtained in an amount of 0.393 grams.

[0017] Next, 0.393 grams of the previously obtained 5-(hydroxy)-2-[(β-D-gluco-pyranosyl)oxy]benzaldehyde is placed in a 25 ml flask and 0.323 grams of sodium acetate and 2.5 ml of acetic anhydride are added. The reaction proceeds at a temperature of 90 °C and constant stirring on a magnetic stirrer with a reflux condenser for 8 hours, and for the next 16 hours at room temperature. The reaction mass is diluted with 10 ml of distilled water and extracted with ethyl acetate 3 times with 20 ml, the phases are separated using a separatory funnel, the organic layer is dried with magnesium sulfate, filtered with a cotton filter and concentrated using a vacuum rotary evaporator. The resulting product is analyzed using 1H NMR ((CDCl3, 400 MHz) δ 2.04, 2.05, 2.06, 2.07 (all s, 12H, CH3CO), 2.30 (3H, s, CH3COPh), 3.88 (1H, ddd, J=9.7, 5.2, 1.8 Hz, H-5 Glu), 4.16 (1H, dd, J=12.4, 1.8 Hz, H-6a Glu), 4.28 (1H, dd, J=12.4, 5.2 Hz, H-6b Glu), 5.14 (1H, d, J=7.3 Hz, H-1 Glu), 5.19 (1H, dd~t, J=9.6 Hz, H-4 Glu), 5.28 – 5.39 (2H, m, H-2 Glu, H-3 Glu), 7.13 (1H, d, J=9.0 Hz, H-6), 7.28 (2H, dd, J=9.0, 2.9 Hz, H-5), 7.54 (1H, d, J=2.9 Hz, H-3), 10.28 (1H, s, COH)) and 13 C NMR ((CDCl3, 101 MHz) δ 20.56, 20.64, 20.9 (5 × CH3CO), 61.6 (C-6 Glu), 68.0 (C-4 Glu), 70.8 (C-2 Glu), 72.2 (C-3 Glu), 72.3 (C-5 Glu), 99.4 (C-1 Glu), 117.4 (C-6), 120.9 (C-3), 127.0 (C-2), 128.9 (C-5), 146.3 (C-4, 156.2 (C-1), 169.2, 169.33, 169.39, 170.2, 170.5 (5 × CH3CO), 188.1 (CHO)) and determine that 5-(acetyloxy)-2-[(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl)oxy]benzaldehyde (6, Fig. 1) was obtained in quantitative yield.

[0018] Next, 0.545 grams of the previously obtained 5-(acetyloxy)-2-[(2,3,4,6-tetra-O-acetyl-β-D-gluco-pyranosyl)oxy]benzaldehyde is placed in a 50 ml flask, dissolved in 10 ml of ethyl acetate, and 10 ml of distilled water is added. As a result, two phases, aqueous and organic, are formed due to the difference in solvent densities. 0.121 grams of sodium borohydride (NaBH4) are added to the same flask and the flask is tightly sealed with a septum. The resulting reaction mixture is stirred with a magnetic stirrer at room temperature for 6 hours. The organic and aqueous phases are then separated using a separatory funnel. The aqueous phase is washed with ethyl acetate three times (10 ml each), and the resulting ethyl acetate portions after washing the aqueous phase are combined with the main organic phase to form a second organic phase. Magnesium sulfate is added to the resulting second organic phase to dry off any remaining water.Magnesium sulfate was filtered using a cotton filter, and the resulting filtrate was concentrated on a rotary evaporator to give 5-(acetyloxy)-2-(hydroxymethyl)phenyl-(2,3,4,6-tetra-O-acetyl)-β-D-glucopyranoside (7, Fig. 1), which was proven by the obtained 1 H NMR spectrum ((400 MHz, CDCl3) δ 2.040, 2.045, 2.06, 2.09 (all s, 12H, 4 × CH3CO), 2.28 (s, 3H, CH 3COPh), 2.44 (1H, dd,J=7.9, 5.6 Hz, OH), 3.82 (1H, ddd,J=10.2, 5.5, 2.3 Hz, H-5 Glu), 4.15 (1H, dd,J=12.4, 2.3 Hz, H-6a Glu), 4.26 (1H, dd,J=12.4, 5.5 Hz, H-6b Glu), 4.49 (1H, dd,J=13.3, 7.9 Hz, H-7a), 4.66 (1H, dd,J=13.3, 5.6 Hz, H-7b), 5.01 – 5.09 (1H, m, H-1 Glu), 5.10 – 5.19 (1H, m, H-4 Glu), 5.26 – 5.35 (2H, m, H-2 Glu, H-3 Glu), 6.97 (1H, dd,J=8.8, 2.6 Hz, H-5), 7.01 (1H, d,J=8.8 Hz, H-6), 7.09 (1H, d,J=2.6 Hz, H-3)) and 13C ЯМР-спектра ((CDCl3, 101 МГц) δ 20.56, 20.59, 20.63, 20.67, 21.0 (5 × CH3CO), 60.5 (C-7), 61.7 (C-6 Glu), 68.1 (C-4 Glu), 71.0 (C-3 Glu), 72.1 (C-2 Glu), 72.3 (C-5 Glu), 99.8 (C-1 Glu), 116.6 (C-6), 121.6 (C-5), 122.2 (C-3), 132.9 (C-2), 146.3 (C-4), 152.0 (C-1), 169.4, 169.6, 169.7, 170.1, 170.6 (5 × CH3CO)).

[0019] To obtain 2-hydroxy-6-methoxybenzoic acid (10, Fig. 1), commercial 2,6-dimethoxybenzoic acid (1 gram) is placed in a 100 ml round-bottomed flask and tightly sealed with a septum. The septum is pierced with a needle attached to a hose from a membrane pump. Air is evacuated from the flask through the needle, and the pressure in the flask is reduced to 1-3 mbar. Under these conditions, the acid is dried for 1 hour, after which the needle, connected by a hose to the membrane pump, is removed. To prevent the ingress of air and moisture into the flask, a needle connected via a hose to a Schlenk line is inserted through the septum, and argon is supplied from a commercial cylinder, which was also connected to a Schlenk line. Using syringes, add 18 ml of dichloromethane (DCM), 0.27 ml of phosphorus tribromide, and 0.14 ml of distilled water through the septum into the flask. The reaction mixture is stirred with a magnetic stirrer at room temperature for 48 hours. The reaction mixture is then diluted with 10 ml of distilled water.The aqueous and organic phases are separated using a separatory funnel, and the organic phase is washed with distilled water (4 x 40 ml each), also separating them using a separatory funnel. The organic layer is dried over magnesium sulfate, filtered through a cotton filter, and concentrated on a vacuum rotary evaporator. The resulting crystals are dissolved in a solvent mixture of 100 ml of diethyl ether and hexane (4:1, respectively) and passed through a 16-pore Schott filter. The resulting precipitate is recrystallized from methanol: 10 ml of methanol is added, the mixture is heated to 70°C, cooled in a freezer at -19°C until a precipitate forms, the precipitate is filtered, and the process is repeated two more times. The resulting precipitate after recrystallization is filtered, dried under reduced pressure of 1-3 mbar and the product 2-hydroxy-6-methoxybenzoic acid (10, Fig. 1) is obtained, which confirms the results obtained. 1H NMR spectrum ((400 MHz, CDCl3) δ 4.1 (s, 3H, H – OCH3), 6.5 (d, J = 8.3 Hz, 1H, H-5), 6.8 (d, J = 8.5 Hz, 1H, H-3), J-H- 7, 7.5 (t 11.39 (s, 1H, H-OH), 12.20 (s, 1H, H-OH)), which are in agreement with the NMR results of the article [Kung HF et al. Dopamine D-2 receptor imaging radiopharmaceuticals: Synthesis, radiolabeling and in vitro binding of (R)-(+)-and (S)-(-)-3-iodo-2-hydroxy-6-methoxy-N-[(1-ethyl-2-pyrrolidinyl) methyl] cheurmistryde of medicinal / / - 1988. - Vol. 31. – No. 5. – S. 1039–1043].

[0020] Next, 0.1 grams of the obtained 5-(acetyloxy)-2-(hydroxymethyl)phenyl-(2,3,4,6-tetra-O-acetyl)-β-D-glucopyranoside (7, Fig. 1) and 0.104 grams of tetrabromomethane (CBr4) are placed in a 10 ml flask and an inert environment is created in it using argon, which is supplied from a cylinder under a pressure of 0.1 MPa, and the flask is closed with a septum. 3 ml of ethyl acetate, previously dried from water, is added to the said flask through the septum using a syringe and the reaction mass is obtained, which is then cooled in an ice bath to 0ºC. In a separate beaker, dissolve 0.087 grams of triphenylphosphine (Ph3P) in 1 ml of ethyl acetate and add the mixture dropwise to the reaction mixture using a syringe while stirring with a magnetic stirrer. Remove the flask from the ice bath and stir its contents at room temperature for 1 hour. Next, concentrate the reaction mixture using a rotary evaporator and fill the flask with argon.After this, 0.032 grams of potassium carbonate and 0.038 grams of 2-hydroxy-6-methoxybenzoic acid (10, Fig. 1), previously dried in separate flasks under vacuum, are added to the flask. All substances are dissolved in 6 ml of N,N-dimethylformamide (DMF). The reaction mixture is stirred using a magnetic stirrer for 16 hours at room temperature, after which it is concentrated using a rotary evaporator. Next, 6 ml of toluene are poured into the flask and concentrated on a rotary evaporator again. The resulting concentrate is purified using column chromatography. A hexane-ethyl acetate mixture in a ratio of 3:1 to 1:2, respectively, is used as an eluent to obtain curculigoside B glycoside pentaacetate (11, Fig. 1), which is confirmed by the results of NMR analysis:. 1H ЯМР ((CDCl3, 400 МГц) ): δ 2.05 (s, 6H, 2×COCH3), 2.08 (s, 3H, COCH3), 2.12 (s, 3H, COCH3), 2.29 (s, 3H, PhCOCH3), 3.80 – 3.86 (m, 1H, H-5 Glu), 3.9 (s, 3H, 3H-OMe), 4.2 (d, J = 11.4 Hz, 1H, H-6b Glu), 4.3 (dd, J = 12.3, 5.2 Hz, 1H, H-6a Glu), 5.0 (d, J = 7.0 Hz, 1H, H-1 Glu), 5.2 (t, J = 9.1 Hz, 1H, H-4 Glu), 5.3 (dd, J = 14.2, 7.2 Hz, 3H, H-2 Glu, H-3 Glu, 7a), 5.4 (d, J = 14.7 Hz, 1H, 7b), 6.4 (d, J = 8.4 Hz, 1H, Н-11), 6.6 (d, J = 8.4 Hz, 1H, Н-13), 7.0 (dd, J = 8.8, 2.1 Hz, 1H, H-5), 7.1 (d, J = 8.8 Hz, 1H, H-6), 7.3 (t, J = 8.3 Hz, 1H, Н-12), 7.37 – 7.40 (m, 1H, H-3), 11.4 (s, 1H, H-OH), 13C ЯМР ((CDCl3, 101 МГц) δ 20.73, 20.74, 20.81 (4×C-COCH3), 21.2 (C-PhCOCH3), 56.1 (C-5 Glu), 61.7 (C-7), 62.0 (C-6 Glu), 68.4 (C-4 Glu), 71.1 (C-2 Glu или C-3 Glu), 72.2 (C-OMe), 72.7 (C-2 Glu или C-3 Glu), 100.1 (C-1 Glu), 102.4 (C-11), 103.1 (С-9), 110.3 (C-13), 117.2 (C-6), 121.4 (С-3), 121.7 (С-5), 128.1 (C-2), 135.50 (С-12), 146.6 (C-4), 151.4 (C-1), 161.2 (C-14), 163.9 (C-10), 169.48, 169.51, 169.72, 170.35 (4×C-COCH3), 170.7 (C-PhCOCH3), COSY ЯМР, HSQC ЯМР, HMBC ЯМР.

[0021] Next, 0.098 grams of curculigoside B glycoside pentaacetate are dissolved in 1 ml of dichloromethane (DCM) in a 10 ml flask. 3 ml of methanol and 0.142 ml of 36 wt% hydrochloric acid are added, and the mixture is stirred with a magnetic stirrer for 90 hours. A cation exchange resin is then added to the reaction mixture, neutralizing the acidic medium to a pH of 7, which is adjusted using indicator paper. The reaction mixture is then filtered through a Schott filter. The cation exchange resin remaining on the Schott filter is washed with methanol (3 times, 5 ml each). The resulting filtrate is concentrated using a rotary evaporator, and the concentrate is purified by column chromatography. A chloroform-methanol mixture in a ratio of 16:1 to 6:1, respectively, was used as an eluent, yielding an additional 0.024 g of crystals of the glycoside curculigoside B (12, Fig. 1), which was proven by NMR analysis: 1H ЯМР (Фиг. 2) ((MeOD-d4, 400 МГц) δ 3.35 – 3.54 (m, 4H, H-2 Glu, H-3 Glu, H-4 Glu, H-5 Glu), 3.7 (dd, J = 12.3, 4.4 Hz, 1H, H-6a Glu), 3.79 – 3.93 (m, 1H, H-6b Glu), 3.85 (s, 3H, OCH3), 4.8 (d, J = 7.1 Hz, 1H, H-1 Glu), 5.5 (s, 2H, H-7), 6.51 (d, J = 8.4 Hz, 1H, H-13), 6.54 (d, J = 9.1 Hz, 1H, H-11), 6.7 (d, J = 8.4 Hz, 1H, H-5), 6.98 (s, 1H, H-3), 7.1 (d, J = 8.7 Hz, 1H, H-6), 7.3 (dd~t, J = 8.4 Hz, 1H, H-12)), 13C NMR (Fig. 3) ((MeOD-d4, 101 MHz) δ 56.6 (C-OCH3), 62.6 (C-6 Glu), 63.5 (C-7), 71.4 (C-4 Glu), 75.0 (C-2 Glu), 78.08 (C-3 Glu), 78.15 (C-5 Glu), 103.6 (C-13), 104.3 (C-1 Glu), 108.1 (C-9), 110.2 (C-11), 116.17, 116.19 (C-3, C-5), 119.0 (C-6), 128.8 (C-2), 134.6 (C-12), 149.6 (C-4), 154.0 (C-1), 161.1 (C-10, C-14), 170.7 (C-8), as well as by methods of homonuclear correlation NMR spectroscopy COSY NMR (Fig. 4), heteronuclear single-quantum correlation spectroscopy HSQC NMR (Fig. 5) and heteronuclear multi-quantum correlation spectroscopy (HMBC) on a Bruker AV-400 HMBC NMR spectrometer (Fig. 6).

Claims

A method for producing curculigoside B glycoside, characterized in that benzoyl chloride is added to hydroquinone in an aqueous solution of sodium hydroxide and stirred for 20 minutes, the resulting reaction mass is filtered, recrystallized from toluene to obtain monobenzoylhydroquinone, which is mixed with urotropine and trifluoroacetic acid, stirred at 77 ° C for 5 hours, hydrochloric acid is added, stirred for 5 minutes and neutralized, after which the resulting solution is extracted with ethyl acetate, dried, filtered, evaporated on a rotary evaporator, purified by column chromatography and mixed with silver oxide (I) and acetobromoglucose, dissolved in quinoline, stirred for 2 hours, diluted with methylene chloride and filtered through a Schott filter, then the resulting filtrate is successively washed with a solution of sodium hydroxide and sulfuric acid, dried, filtered, evaporated on a rotary evaporator and purified by column chromatography, after which sodium methylate is added,dissolved in methanol and stirred for 4.5 h, then neutralized with a cation exchange resin, filtered, evaporated on a rotary evaporator, purified by column chromatography and mixed with sodium acetate and acetic anhydride, stirred at 90 °C for 8 h and then at room temperature for 16 h, extracted with ethyl acetate, dried, filtered, evaporated on a rotary evaporator and dissolved in ethyl acetate, then distilled water is poured in and sodium borohydride is added, stirred for 12 h, extracted with ethyl acetate, dried, filtered and evaporated on a rotary evaporator to obtain 5-(acetyloxy)-2-(hydroxymethyl)phenyl-(2,3,4,6-tetra-O-acetyl)-β-D-glucopyranoside, which is dried under reduced pressure in a flask, after which to argon is supplied to the flask and dissolved in dried ethyl acetate, a solution of tetrabromomethane in dried ethyl acetate is added, cooled in an ice bath and a solution of triphenylphosphine in dried ethyl acetate is added, stirred at room temperature for 1 hour,evaporated on a rotary evaporator, dried for 1 hour under reduced pressure, supplied with argon, added potassium carbonate and 2-hydroxy-6-methoxybenzoic acid, dissolved the mixture in N,N-dimethylformamide, stirred for 16 hours, evaporated on a rotary evaporator, purified by column chromatography to obtain pentaacetate of the glycoside curculigoside B, which is dissolved in dichloromethane, methanol and hydrochloric acid are added, stirred for 90 hours, neutralized with a cation exchange resin, filtered, evaporated on a rotary evaporator and purified by column chromatography to obtain curculigoside B.

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