TW201402112A - New secoiridoids and bioactive constituents from Fraxinus chinensis and their preparation method - Google Patents

Abstract

Fraxinus chinensis are widely used in traditional Chinese medicine for reducing inflammation, stopping cough, improving gastrointestinal disease, and as a diuretic. The phytochemical investigation of stem bark of F. chinensis has led to the isolation of three new secoiridoid derivatives, (8E)-4''-O-methylligstroside (1), (8E)-4''-O-methyldemethylligstroside (2), and 3'', 4''-di-O-methyl- demethyloleuropein (3), along with 12 known compounds. The structures of all isolates were determined through spectral analyses (including 2D-NMR: NOESY, COSY, HMBC, HSQC...etc) and comparison of their physical and spectral data with literatures. The anti-inflammatory effects of compounds from F. chinensis were evaluated by suppressing formyl-L-methionyl-L-leucyl-L-phenylalanine/cytochalasin B (fMLP/ CB)-induced superoxide radical anion (O2) generation and elastase release by human neutrophils. The result of anti-inflammatory test showed that (8E)-4''-O-methylligstroside (1), (8E)-4''-O-methyl-demethylligstroside (2), 3'', 4''-di-O-methyldemethyloleuropein (3), oleuropein (5), aesculetin (7), isoscopoletin (9), aesculetin dimethyl ester (10), fraxetin (12), tyrosol (13), 4-hydroxyphenethyl acetate (14), and (+)-pinoresinol (15) exhibited inhibition (IC50 values ≤ 7.65 g/mL) of superoxide anion generation by human neutrophils in response to formyl-L-methionyl-L-leuckyl-L- phenylalanine/cytochalasin B (fMLP/ CB). In addition, (8E)-4''-O-methylligstroside (1), aesculetin (7), isoscopoletin (9), fraxetin (12), tyrosol (13), and 4-hydroxyphenethyl acetate (14) inhibited fMLP/CB-induced elastase release with IC50 values ≤ 3.23 g/mL.

Description

New cracked iridoids extracted from ash tree and biologically active component and preparation method thereof

The present invention relates to a sphagnum tree extracting new split iridoid oxime and a biologically active ingredient thereof and a preparation method thereof; more specifically, a method for analyzing three new secoiridoid compounds from ash tree: (8 E )-4 "- O -methylligstroside (1), (8 E) -4" - O -methyldimethylligstroside (2) , and 3 ", 4" -di- O -methyldemethyloleuropein (3) of the analysis system. In addition, the results of the anti-inflammatory activity test showed (8 E )-4 " - O -methylligstroside( 1 ), (8 E )-4 " - O -methyldimethyl-ligstroside( 2 ), 3 " , 4 " -di- O -methyldemethyloleuropein( 3 ), oleuropein( 5 ), aesculetin( 7 ),isoscopoletin( 9 ), aesculetin dimethyl ester( 10 ),fraxetin( 12 ),tyrosol( 13 ),4-hydroxyphenethyl acetate( 14 ), and (+) -pinoresinol( 15 ) has good inhibitory activity on the production of superoxide anion (O ₂ ^.- ) induced by fMLP/CB (IC _{50 )} 7.65 μg/mL). In addition, (8 E )-4 " - O -methylligstroside ( 1 ), aesculetin ( 7 ), isoscopoletin ( 9 ), fraxetin ( 12 ), tyrosol ( 13 ) and 4-hydroxyphenethyl acetate ( 14 ) were induced by fMLP/CB Release of elastase (elastase) with good inhibition (IC ₅₀ 3.23 μg/mL).

Ash tree belongs to deciduous tree, distributed in China, Japan, Korea, Russia and Vietnam. The bark of ash tree is also called Qinpi. It is listed as "Chinese medicine" in the "Shen Nong's Herbal Classic". It has been recorded in the past dynasties. Heat and dampness, astringent, eyesight, mainly used to treat phlegm, diarrhea, redness, redness, swelling, pain, eyelid membrane; ash tree has anti-inflammatory analgesic, cough, expectorant, asthma, diuretic, promotion Urinary acid excretion, promote blood circulation, inhibit intestinal peristalsis, anti-tumor, anti-allergy, anti-ultraviolet effect, anti-microbial and other effects.

The inventor of this case has been engaged in medical related research for many years, and has a considerable understanding of medical related knowledge. It is known from the above analysis that ash tree has a wide therapeutic effect, and the inventors believe that the therapeutic effect of this medicinal material should not stop there, so whether research on ash tree is concerned There are also new treatment features.

In view of this, the inventor of the present invention has carried out in-depth research on the above-mentioned research and development experience in the related fields, and has searched for a new method for extracting compounds according to the foregoing, and has completed the present invention after a long period of hard research and multiple tests.

The main object of the present invention is to provide a novel cleavage iridoid and a biologically active ingredient extracted from ash tree and a preparation method thereof, and to analyze three kinds of new secoiridoid compounds and compounds having anti-inflammatory activity by various experimental data.

A. Using the extraction, chromatography, purification and structural resolution steps described in the present invention, three new compounds were found: (8 E )-4 " - O -methylligstroside( 1 ), (8 E )-4 " - O - Methyldimethyl-ligstroside ( 2 ) and 3 " , 4 " -di- O -methyldemethyloleuropein ( 3 ).

B. Experimental data for three new compounds are as follows: (8 E )-4 " - O -methylligstroside( 1 ): yellow oil; [α] ²⁵ _D = -182.2 ° ( c 0.2, MeOH); UV (MeOH) λ _Max (log ε) 238 (4.05), 276 (3.82), 283 (3.81), 318 (3.76) nm; IR (neat) υ _max 3402 (OH), 1727 (C=O), 1709 (C=O) Cm ^-1 ; ¹ H NMR (CD ₃ OD, 500 MHz): δ 1.63 (3H, dd, J = 7.0, 1.0 Hz, H-10), 2.44 (1H, dd, J =14.0, 9.5 Hz, H _α -6), 2.69 (1H, dd, J = 14.0, 4.5 Hz, H _β -6), 2.85 (2H, t, J = 7.0 Hz, H-β), 3.30-3.35 (3H, m, H-2 ' , 4 ' , 5 ' ), 3.41 (1H, dd, J = 9.0, 8.5 Hz, H-3 ' ), 3.66 (1H, dd, J = 12.0, 5.5 Hz, H-6 ' ), 3.71 (3H) , s, OMe-11), 3.76 (3H, s, OMe-4 " ), 3.88 (1H, dd, J = 12.0 Hz, H-6 ' ), 3.96 (1H, m, J = 9.5, 4.5 Hz, H-5), 4.12 (1H, dt, J = 10.5, 7.0 Hz, H-α), 4.24 (1H, dt, J = 10.5; 7.0 Hz, H-α), 4.80 (1H, d, J = 8.0 Hz, H-1 ' ), 5.92 (1H, br s, H-1), 6.06 (1H, br q, J = 7.0, H-8), 6.85 (each 1H, d, J = 9.0 Hz, H- 3 " , 5 " ), 7.15 (each 1H, d, J = 9.0 Hz, H-2 " , 6 " ), 7.51 (1H, s, H-3); ¹³ C NMR (CD ₃ OD, 125 MHz) : δ 13.7 (C-10), 32.0 (C-5), 35.2 (C-β), 41.3 (C-6), 52.1 (OMe-11), 55.9 (OMe-4 " ), 62.9 (C-6 ' ), 67.0 (C-α), 71.7 (C-4 ' ), 74.9 (C-2 ' ), 78.1 (C-3 ' ), 78.6 (C-5 ' ), 95.3 (C-1), 101.0 (C-1 ' ), 109.5 (C-4), 115.1 (C-3 " , 5 " ), 125.1 (C-8), 130.1 (C-9), 131.2 (C-2 " , 6 " ), 131.5 (C-1 " ), 155.3 (C-3), 160.0 (C-4 " ), 168.9(C-11), 173.4(C-7); ESIMS m/z 561[M+Na] ⁺ ; HRESIMS m/z 561.1950 [M+Na] ⁺ (calcd for C ₂₆ H ₃₄ O ₁₂ Na, 561.1948) .

(8 E )-4 " - O -methyldimethylligstroside ( 2 ): yellowish oil; [α] ²⁵ _D = -182.5 ° ( c 0.25, MeOH); UV (MeOH) λ _max (log ε) 225 (4.04), 276 (3.80), 282 (3.79), 317 (3.73) nm; IR (KBr) υ _max 3334 (OH), 1728 (C=O), 1707 (C=O) cm ^-1 ; ¹ H-NMR (CD ₃ OD, 500 MHz) δ 1.66 (3H, dd, J = 7.0, 1.0 Hz, H-10), 2.41 (1H, dd, J = 14.0, 9.5 Hz, H-6), 2.79 (1H, dd, J = 14.0, 4.5 Hz, H-6), 2.85 (2H, t, J = 7.0 Hz, H-β), 3.29-3.35 (3H, m, H-2 ' , 4 ' , 5 ' ), 3.41 (1H, Dd, J = 9.0, 8.5 Hz, H-3 ' ), 3.67 (1H, dd, J = 12.0, 5.5 Hz, H-6 ' ), 3.76 (3H, s, OMe-4 " ), 3.88 (1H, Dd, J =12.0, 1.5 Hz, H _β -6 ' ), 4.01 (1H, m, J = 9.5, 5.0 Hz, H-5), δ 4.12 (1H, dt, J = 10.5, 7.0 Hz, H- α), 4.23 (1H, dt, J = 10.5, 7.0 Hz, H-α), 4.80 (1H, d, J = 8.0 Hz, H-1 ' ), 5.87 (1H, br s, H-1), 6.05 (1H, br q, J = 7.0, H-8), 6.85 (each 1H, d, J = 9.0 Hz, H-3 " , 5 " ), 7.15 (each 1H, d, J = 9.0 Hz, H -2 " , 6 " ), 7.39 (1H, s, H-3); ¹³ C-NMR (CD ₃ OD, 125 MHz) δ 13.6 (C-10), 31.9 (C-5), 35.2 (C- β), 41.3 (C-6), 55.9 (OMe-4 " ), 62.9 (C-6 ' ), 66.9 (C-α), 71.6 (C-4 ' ), 74.9 (C-2 ' ), 78.1 (C-3 ' ), 78.6 (C-5 ' ), 95.0 (C-1), 101.0 (C-1 ' ), 110.2 (C-4), 115.1 (C-3 " , 5 " ), 125.1 (C-8), 130.1 (C-9), 131.2 (C-2 " , 6 " ), 131.5 (C-1 " ), 152.8 (C-3), 160.0(C-4 " ), 171.0(C-11), 173.3(C-7); ESI-MS m/z 547[M+Na] ⁺ ; HR-ESI-MS m/z 547.1787[M+Na] ⁺ (calcd for C ₂₅ H ₃₂ O ₁₂ Na, 547.1791).

3 " , 4 " -di- O -methyldemethyloleuropein ( 3 ): amorphous powder; [α] ²⁵ _D = -155.2 ° ( c 0.22, MeOH); UV (MeOH) λ _max (log ε) 226 (4.24), 277 (3.40) nm; IR (KBr) υ _max 3350 (OH), 1721 (C=O), 1698 (C=O) cm ^-1 ; ¹ H-NMR (CD ₃ OD, 500 MHz) δ 1.66 (3H, Dd, J = 7.0, 1.0 Hz, H-10), 2.41 (1H, dd, J = =14.0, 9.5 Hz, H _α -6), 2.80 (1H, dd, J = 14.0, 4.5 Hz, H _β -6 ), 2.86 (2H, t, J = 7.0 Hz, H-β), 3.28-3.36 (3H, m, H-2 ' , 4 ' , 5 ' ), 3.41 (1H, dd, J = 8.5, 8.5 Hz) , H-3 ' ), 3.66 (1H, dd, J = 12.0, 5.5 Hz, H-6 ' ), 3.80 (3H, s, OMe-4 " ), 3.82 (3H, s, OMe-3 " ), 3.88 (1H, dd, J = 12.0, 1.5 Hz, H-6 ' ), 4.00 (1H, dd, J = 9.5, 4.5 Hz, H-5), 4.15 (1H, dt, J = 10.5, 7.0 Hz, H-α), 4.27 (1H, dt, J = 10.5; 7.0 Hz, H-α), 4.80 (1H, d, J = 8.0 Hz, H-1 ' ), 5.86 (1H, br s, H-1 ), 6.06 (1H, br q, J = 7.0, H-8), 6.79 (1H, dd, J = 8.5; 2.0 Hz, H-2 " ), 6.86 (1H, d, J = 2.0 Hz, H- 2 " ), 6.88 (1H, d, J = 8.5 Hz, H-5 " ), δ 7.38 (1H, s, H-3); ¹³ C-NMR (CD ₃ OD, 125 MHz) δ 13.6 (C- 10), 32.0 (C-5), 35.7 (C-β), 41.3 (C-6), 56.7 (OMe × 2), 62.9 (C-6 ' ), 66.8 (C-α), 71.6 (C- 4 ' ), 74.9 (C-2 ' ), 78.1 (C-3 ' ), 78.6 (C-5 ' ), 95.3 (C-1), 101.0 (C-1 ' ), 110.1 (C-4), 113.3 (C-5 " ), 114.1 (C-3 " ), 122.6 (C-6 " ), 124.7 (C-8), 130.6 (C-9) ), 132.5(C-1 " ), 149.3 (C-4 " ), 150.5 (C-3 " ), 152.9 (C-3), 171.0 (C-11), 173.3 (C-7); ESI-MS m/z 577 [M+Na] ⁺ ; HR-ESI-MS m/z 577.1892 [M+Na] ⁺ (calcd for C ₂₆ H ₃₄ O ₁₃ Na, 577.1897).

C. A compound isolated from ash, which produces superoxide anion (O ₂ ^.- ) by inhibiting human neutrophils induced by foryl-L-methionyl-L-leucyl-L-phenylalanine/cytochalasin B (fMLP/CB) The effect of elastase was evaluated to evaluate its anti-inflammatory activity. The results of the anti-inflammatory activity test showed (8 E )-4 " - O -methylligstroside( 1 ),(8 E )-4 " - O -methyldimethylligstroside( 2 ),3 " ,4 " -di- O -methyldemethyl-oleuropein ( 3 ), oleuropein ( 5 ), aesculetin ( 7 ), isoscopoletin ( 9 ), aesculetin dimethyl ester ( 10 ), fraxetin ( 12 ), tyrosol ( 13 ), 4-hydroxyphenethyl acetate ( 14 ), and (+)-pinoresinol ( 15 ) Good inhibitory activity (IC ₅₀ ) for the production of superoxide anion (O ₂ ^.- ) induced by fMLP/CB 7.65 μg/mL). In addition, (8 E )-4 " - O -methylligstroside ( 1 ), aesculetin ( 7 ), isoscopoletin ( 9 ), fraxetin ( 12 ), tyrosol ( 13 ) and 4-hydroxyphenethyl acetate ( 14 ) were induced by fMLP/CB Release of elastase (elastase) with good inhibition (IC ₅₀ 3.23 μg/mL).

D. Among all the isolated compounds, (8 E )-4 " - O -methylligstroside ( 1 ) and fraxetin ( 12 ) are the most effective compounds for inhibiting the production of superoxide anion induced by fMLP/CB and elastase The IC ₅₀ values for release were 0.08 ± 0.01 and 0.50 ± 0.10 μg / mL, respectively. These two compounds have the potential to be developed as anti-inflammatory drugs.

In order to have a more detailed understanding of the features and structures of the present invention, please refer to Annex I; Annex I is a data chart of the analysis results of the compound of the present invention. The method for preparing a new biphenyl compound for extracting according to the present invention has the following steps:

A. The ash stem bark was chopped and dried to obtain a total of 4.0 kg, which was extracted three times with methanol, and the resulting extract was concentrated under reduced pressure to give a MeOH extract of 384 g, followed by EtOAc:H ₂ O (1: The mixture was partitioned with EtOAc (EtOAc m. The H ₂ O layer extract was further partitioned with n -Hexane (1:1, v/v) to obtain n -B Hexane layer extract (Fr. B, 56 g) and H ₂ O layer extract (Fr. C, 119 g).

B. The EtOAc layer extract (Fr. A, 180 g) was separated by column chromatography, starting with CH ₂ Cl ₂ and gradually increasing CH ₂ Cl ₂ and MeOH to increase the polarity. A total of 10 divisions were obtained: Fr.A1 (5 L, CH ₂ Cl ₂ ), A2 (6 L, CH ₂ Cl ₂ /MeOH, 90:1), A3 (9 L, CH ₂ Cl ₂ /MeOH, 80:1), A4 (6) L, CH ₂ Cl ₂ /MeOH, 60:1), A5 (5 L, CH ₂ Cl ₂ /MeOH, 50:1), A6 (10 L, CH ₂ Cl ₂ /MeOH, 40:1), A7 ( 5 L, CH ₂ Cl ₂ /MeOH, 20:1), A8 (3 L, CH ₂ Cl ₂ /MeOH, 10:1), A9 (4 L, CH ₂ Cl ₂ /MeOH, 1:1), A10 (2 L, MeOH).

C. Fr.A1 (5.8 g) was separated by column chromatography and eluted with n- hexane/acetone (2:1) to obtain 8 fractions (each 500 mL, Fr.A1-1~A1-8) ). 4-hydroxyphenethyl acetate ( 14 ) (6.6 mg) was obtained from Fr. A1-1 (R _f = 0.78). Fr. A 1-5 (mg) was purified by preparative TLC (silica gel, CH ₂ Cl ₂ /EtOAc, 8:1) to afford (+)-pinoresinol( 15 ) (5.5 mg) ( _Rf = 0.32).

D. Fr. A3 (7.8 g) was separated by column chromatography and eluted with n- hexane/EtOAc (1:1). A total of 10 fractions were obtained (each 300 mL, Fr.A3-1~Fr .A3-10). Isoscopoletin ( 9 ) (1.0 mg) was obtained from Fr. A3-1 (R _f = 0.81). Fr. A 3-4 (190 mg) was purified by preparative TLC (silica gel, CH ₂ Cl ₂ /MeOH, 25:1) to afford fraxidin ( 11 ) (1.5 mg) ( _Rf = 0.41). Tyrosol ( 13 ) (4.9 mg) was obtained from Fr. A3-8 ( _Rf = 0.52). Fr. A3-10 (190 mg) was purified by preparative TLC (silica gel, n- hexane/EtOAc, 1:1) to afford fraxetin ( 12 ) (5.9 mg) ( _Rf = 0.30).

E. Fr. A4 (8.5 g) was separated by column chromatography and extracted with CH ₂ Cl ₂ /acetone (10:1). A total of 5 divisions were obtained (each 1.2 L, Fr.A4-1~Fr. A4-5). Fr.A4-2 was again separated by column chromatography and eluted with n- hexane/acetone (3:2). A total of 4 divisions were obtained (each 1.2 L, Fr.A4-2-1~Fr.A4- 2-4). Fr. A4-2-3 (195 mg) was purified by preparative TLC (silica gel, CH ₂ Cl ₂ / EtOAce, 15:1) to afford scopoletin ( 8 ) (3.1 mg) ( _Rf = 0.39). Fr. A4-3 (192 mg) was purified by preparative TLC (silica gel, CH ₂ Cl ₂ /acetone, 5:1) to afford aesculetin ( 7 ) (3.9 mg) ( _Rf = 0.46).

F. Fr. A6 (8.2 g) was separated by column chromatography eluting with CH ₂ Cl ₂ /EtOAc (10:1) to give a total of 7 divisions (each 1 L, Fr.A6-1~Fr .A6-7). Fr. A6-4 (180 mg) was purified by preparative TLC (silica gel, n- hexane/EtOAc, 2:1) to afford aesculetin dimethyl ester ( 10 ) (1.5 mg) ( _Rf = 0.71). Fr. A6-7 (28 mg) was purified by preparative TLC (silica gel, CHCl ₃ /MeOH 8:1) to afford oleoside methyl ester ( 6 ) (4.5 mg) ( _Rf = 0.19).

G. Fr. A9 (7.3 g) was separated by column chromatography and eluted with CH ₂ Cl ₂ /MeOH (7:1) to obtain 4 partitions (each 500 mL, Fr.A9-1~) Fr. A9-4). Fr.A9-2 (202 mg) to _{preparative TLC (silica gel, CHCl 3} / MeOH 7: 1) to give (8 E) -4 "- O -methylligstroside (1) (4.5 mg) (R f = 0.66 Fr.A9-4 (188 mg) was again separated by column chromatography and eluted with CHCl ₃ /MeOH (3:1) to give a total of 2 divisions (each 150 mL, Fr.A9-4-1) ~Fr.A9-4-2).Fr. A9-4-1 (210 mg) was purified by preparative TLC (silica gel, CHCl ₃ /MeOH, 4:1) to give 3 " ,4 " -di- O- methyldemethyloleuropein (3) (3.1 mg) (R f = 0.61) .Fr.A9-4-2 (205 mg) to _{preparative TLC (silica gel, CH 2} Cl 2 / MeOH, 5: 1) to give (8 E )-4 " - O -methyldimethylligstroside ( 2 ) (4.2 mg) (R _f = 0.55).

H. Fr. A10 (6.8 g) was separated by column chromatography and eluted with CH ₂ Cl ₂ /MeOH (7:1) to obtain 4 partitions (each 700 mL, Fr.A10-1~) Fr.A10-4). Fr.A10-1 (200 mg) preparative TLC to _{(silica gel, CHCl 3 / MeOH} , 7: 1) to give (8 E) -ligstroside (4) (7.3 mg) (R f = 0.65). Fr. A10-2 (180 mg) was purified by preparative TLC (silica gel, CH ₂ Cl ₂ /acetone 1:2) to afford oleuropein ( 5 ) (3.6 mg) ( _Rf = 0.35).

The purified compound obtained in the above step was tested for anti-inflammatory activity as shown in the following steps:

First, the experimental materials:

(A) Compounds isolated from the bark of the ash tree

(B)human neutrophils

(C)HBSS: Hank’s buffered saline solution

(D)fMLP: formyl-L-methionyl-L-leucyl-L-phenylalanine

(E)CB: cytochchalasin B

(F)SOD: superoxide dismutase

(G)ferricytochrome c

Second, the experimental method:

(A) Preparation of human neutrophils

Healthy blood donors aged 20-30 years old (normal work and no drugs for more than two weeks), blood collection in the elbow vein by vacuum aseptic blood collection, about 30-80 ml. The neutrophils were separated by Ficoll gradient centrifugation as follows: 25 ° C, 650 g, male whole blood was centrifuged for 10 min, female whole blood was centrifuged for 8 min, the supernatant was removed, and the lower blood cells were fractionated and 3%. The dextran solution was mixed in an equal volume and allowed to stand at room temperature for 30 min. The upper layer containing abundant neutrophils was covered in a 50 ml centrifuge tube of an equal volume of Histopaque-1077 solution, centrifuged at 400 g for 20 min at 20 ° C, and pellets were taken. The remaining red blood cells are broken by a method of hemolysis of a low-tension solution. Finally, the supernatant was removed by centrifugation at 4 ° C, and the separated neutrophils were suspended in Hank's buffered saline solution (HBSS) in an ice bath.

(B) Determination of superoxide anion radical (O ₂ ^.- ) release

A suspension of neutrophils (6×10 ⁵ cells/ml) containing 0.5 mg/ml ferricytochrome c , 1 mM CaCl ₂ and 1 mM MgCl ₂ was preheated for 5 minutes to reach 37 ° C. After 5 minutes of drug action, fMLP (0.1 μM)/cyto-chalasin B (CB, 1 μg/ml) was added for further 10 minutes. The absorbance was measured at a wavelength of 550 nm using an ultraviolet spectrophotometer. In the experiment, the amount of superoxide radical released by neutrophils (extinction coefficient 21.1/mM/cm) was evaluated by superoxide dismutase (SOD, 100 U/ml) to inhibit ferricytochrome c reduction.

△A ₅₅₀ =extinction coefficient×1×△C

△C=△A ₅₅₀ /(21.1/mM/cm×1 cm)

△C=△A ₅₅₀ × 47.4 nmol/ml

Among them, the absorbance of the sample of △A _{550 to} be tested is subtracted from the absorbance of the SOD inhibition group, and ΔC is the O ₂ of the sample to be tested ^{. -} Production.

(C) Determination of elastase release

The suspension of neutrophils contains Methoxysuccinyl-Ala-Ala-Pro-Val-p-nitroanilide (Ms-Ala-Ala-Pro-Val-pNA), preheated for 5 minutes to reach 37 ° C, and added to the drug to be tested 5 After a minute, the fMLP/CB reaction was further added for 10 minutes. The absorbance was measured at a wavelength of 405 nm using an ultraviolet spectrophotometer.

Third, the experimental principle:

Using fMLP/CB (formyl-L-methionyl-L-leucyl-L-phenylalanine/cyto-chalasin B) to induce neutrophil to produce superoxide anion and elastase, and super The production of oxygen anions and the release of elastase are associated with the development of inflammatory diseases. Therefore, the anti-inflammatory activity of the isolated compound can be evaluated by the inhibitory effect of fMLP/CB on induction of superoxide anion production and elastase release.

Fourth, statistical analysis:

The experimental results were presented as mean ± standard deviation (SEM) (n = 4), and compared using "Student's t test", a probability of 0.05 or less was considered statistically significant.

V. Results and discussion

The chemical constituents of the vines of the genus Oleaceae were studied. At present, three new secoiridoid compounds were isolated from the thick bark: (8 E )-4 " - O -methylligstroside( 1 ), (8 E )-4 " -O- methyldimethylligstroside( 2 ) and 3 " ,4 " -di- O- methyldemethyl-oleuropein( 3 ), and 12 known compounds ( 4-15 ). The above compounds were analyzed by various experimental data (including 2D-NMR: NOESY, COSY, HMBC, HSQC, etc.) and the data in the related literature were confirmed.

1. Compound structure identification

Three are new biphenyl compounds ( 1-3 ) with UV, IR, ESI-MS, HR-ESI-MS, NMR ( ¹ H-NMR, ¹³ C-NMR, DEPT, COSY, NOESY, HSQC, HMBC.. ..), ..... and other experimental materials determine the chemical structure. Twelve known compounds ( 4-15 ), including 3 secoiridoids (8 E )-ligstroside ( 4 ), oleuropein ( 5 ) and oleoside methyl ester ( 6 ); 6 coumarins: aesculetin ( 7 ), scopoletin ( 8 ),isoscopoletin( 9 ), aesculetin dimethyl ether( 10 ),fraxidin( 11 ) and fraxetin( 12 ); 2 phenylethanoids:tyrosol( 13 ) and 4-hydroxyphenethyl acetate( 14 ) and 1 lignan:(+)-pinoresinol ( 15 ), compared with the literature data, its ¹ H-NMR, IR, UV, MS and other data, the results are consistent to determine its structure.

2. Physiological activity research

Inflammation is the normal defense response of the human body. In order to combat the foreign pathogens, the protective mechanism is characterized by red, hot, swollen, painful symptoms. When white blood cells fight against foreign pathogens, high-oxidation free radicals are used, which not only kills foreign pathogens, but also the surrounding normal tissues or cells are often affected. Once the DNA of a normal cell is damaged, the gene will mutate and affect the growth and differentiation of the cell. If mutations are made in important genes, the chances of developing malignant tumors increase. Because chronic inflammation is a normal thinning after years Cellular, chromosomal variations have also been accumulating, eventually leading to cancer, or the immune system may also cause many chronic degenerative diseases to begin to occur due to long-term load.

Research indicates that about 30% of cancers are associated with chronic inflammation or chronic infections; especially myocardial infarction, diabetes, Alzheimer's disease, cancer, allergic and autoimmune diseases, and more and more The evidence shows that it is closely related to chronic inflammation. For example, some people with heart attacks, in fact, their cholesterol is not high, the atherosclerotic block caused by chronic inflammation on the blood vessel wall, the initiation of coagulation mechanism, obstruction of the coronary artery is the cause of myocardial infarction; chronic liver Inflammation turns into liver cancer, which is caused by the attack of the immune system; cervical cancer is also caused by the inflammatory reaction against human papillomavirus in the body; the reflux of gastric juice causes esophageal inflammation and is also prone to esophageal cancer. Therefore, in theory, if the inflammatory response can be blocked, the cancer cells can be significantly inhibited.

When human neutrophil is stimulated and activated, it releases active oxygen such as superoxide anion (O ₂ ^.- ), hydrogen peroxide and hydroxyl radical. [(Reactive oxygen species (ROS)], and release of elastase (elastase), β-glucuronidase, lysozyme, PAF and other media, and these substances are related to inflammatory diseases such as: rheumatoid arthritis, kidney skein Nephritis, skin disease, ischemic reperfusion injury, myocardial infarction, chronic lung obstruction and asthma. Inhibition of neutrophilic leukemia or inappropriate activation is thought to improve these inflammatory diseases. Therefore, new treatment and prevention of inflammation The development of drugs for diseases has been a hot topic in the research of the pharmaceutical industry. Studies on anti-inflammatory active ingredients isolated from natural materials in the past have shown that flavonoids, terpenoids and lignans have good anti-inflammatory activity, so they are In vitro screening of anti-inflammatory tests, selection of plants with anti-inflammatory activity compared to "good" plants versus It is a feasible way to develop new anti-inflammatory drugs.

a compound isolated from the stem of ash tree, which produces superoxide anion (O ₂ ^.- ) by inhibiting human neutrophils induced by foryl-L-methionyl-L-leucyl-L-phenylalanine/cytochalasin B (fMLP/CB) The effect of elastase to evaluate its anti-inflammatory activity. Anti-inflammatory activity data is listed in Table 1. Diphenyleneiodonium and phenylmethylsulfonyl fluoride were treated as [O ₂ ^{. -} Produce] and [elastase release] positive control. For the results of the anti-inflammatory test, the following seven conclusions can be summarized:

(a)(8 E )-4 " - O -methylligstroside( 1 ),(8 E )-4 " - O -methyldimethyl-ligstroside( 2 ),3 " ,4 " -di- O -methyldemethyloleuropein( 3 ), Oleuropein( 6 ), aesculetin( 9 ),isoscopoletin( 11 ), aesculetin dimethyl ester( 12 ),fraxetin( 14 ),tyrosol( 21 ),4-hydroxyphenethyl acetate( 22 ) and (+)-pinoresinol( 24 ) for fMLP /CB induces the production of superoxide anion with good inhibitory activity (IC ₅₀ 7.65 μg/mL).

(b)(8 E )-4 " - O -methylligstroside( 1 ), aesculetin( 9 ),isoscopoletin( 11 ), fraxetin( 14 ), tyrosol( 21 ) and 4-hydroxyphenethyl acetate( 22 ) for fMLP/CB Induces elastase release with good inhibitory activity (IC ₅₀ 3.23 μg/mL).

(C) "having a methoxyl group of (8 E) -4-bit" in the C-4 - O -methylligstroside (1 ), for superoxide anion and elastase inhibitory effect than similar compounds (8 E) -ligstroside ( 5) (C-4 " bit with hydroxy group) is more effective.

(d) Inhibition effect of aesculetin( 7 ) having a 6,7-dihydroxy group on superoxide anion (O ₂ ^.- ) in a coumarin-like compound ( 7-10 ) having a substituent at the C-6,7 position 8-10 is more effective.

(e) In the coumarin-like compound ( 11,12 ) having a substituent at the C-6,7,8 position, the fraxetin( 12 ) having a 7-hydroxy group has an inhibitory effect on superoxide anion and elastase. The similar compound fraxedin( 11 ) (the C-7 position has a methoxy group) is more effective.

(f) Among all the isolated compounds, (8 E )-4 " - O -methylligstroside ( 1 ) and fraxetin ( 12 ) are the most potent compounds for inhibiting the production of superoxide anion induced by fMLP/CB and elastase The IC ₅₀ values of the release were 0.08 ± 0.01 and 0.50 ± 0.10 μg / mL, respectively.

Claims (5)

A method for preparing a new cleavage iridoids and a biologically active component extracted from ash tree is prepared by the following steps: A. The stalk of the ash tree is chopped and dried to obtain 4.0 kg, and is extracted by methanol cold dipping three times. , obtained from the extraction was dried and concentrated under reduced pressure, MeOH extract to give 384 g, followed by _{EtOAc: H 2 O (1:} 1, v / v) was partitioned to obtain EtOAc layer was withdrawn, dried and concentrated under reduced pressure to give EtOAc Layer extract (Fr. A, 180 g). The H ₂ O layer extract was further partitioned with n -Hexane (1:1, v/v) to obtain n -B Hexane layer extract (Fr. B, 56 g) and H ₂ O layer extract (Fr. C, 119 g). B. The EtOAc layer extract (Fr. A, 180 g) was separated by column chromatography, starting with CH ₂ Cl ₂ and gradually increasing CH ₂ Cl ₂ and MeOH to increase the polarity. A total of 10 divisions were obtained: Fr.A1 (5 L, CH ₂ Cl ₂ ), A2 (6 L, CH ₂ Cl ₂ /MeOH, 90:1), A3 (9 L, CH ₂ Cl ₂ /MeOH, 80:1), A4 (6) L, CH ₂ Cl ₂ /MeOH, 60:1), A5 (5 L, CH ₂ Cl ₂ /MeOH, 50:1), A6 (10 L, CH ₂ Cl ₂ /MeOH, 40:1), A7 ( 5 L, CH ₂ Cl ₂ /MeOH, 20:1), A8 (3 L, CH ₂ Cl ₂ /MeOH, 10:1), A9 (4 L, CH ₂ Cl ₂ /MeOH, 1:1), A10 (2 L, MeOH). C. Fr.A1 (5.8 g) was separated by column chromatography and eluted with n- hexane/acetone (2:1) to obtain 8 fractions (each 500 mL, Fr.A1-1~A1-8) ). 4-hydroxyphenethyl acetate ( 14 ) (6.6 mg) was obtained from Fr. A1-1 (R _f = 0.78). Fr. A 1-5 (mg) was purified by preparative TLC (silica gel, CH ₂ Cl ₂ /EtOAc, 8:1) to afford (+)-pinoresinol( 15 ) (5.5 mg) ( _Rf = 0.32). D. Fr. A3 (7.8 g) was separated by column chromatography and eluted with n- hexane/EtOAc (1:1). A total of 10 fractions were obtained (each 300 mL, Fr.A3-1~Fr .A3-10). Isoscopoletin ( 9 ) (1.0 mg) was obtained from Fr. A3-1 (R _f = 0.81). Fr. A 3-4 (190 mg) was purified by preparative TLC (silica gel, CH ₂ Cl ₂ /MeOH, 25:1) to afford fraxidin ( 11 ) (1.5 mg) ( _Rf = 0.41). Tyrosol ( 13 ) (4.9 mg) was obtained from Fr. A3-8 ( _Rf = 0.52). Fr. A3-10 (190 mg) was purified by preparative TLC (silica gel, n- hexane/EtOAc, 1:1) to afford fraxetin ( 12 ) (5.9 mg) ( _Rf = 0.30). E. Fr. A4 (8.5 g) was separated by column chromatography and extracted with CH ₂ Cl ₂ /acetone (10:1). A total of 5 divisions were obtained (each 1.2 L, Fr.A4-1~Fr. A4-5). Fr.A4-2 was again separated by column chromatography and eluted with n- hexane/acetone (3:2). A total of 4 divisions were obtained (each 1.2 L, Fr.A4-2-1~Fr.A4- 2-4). Fr. A4-2-3 (195 mg) was purified by preparative TLC (silica gel, CH ₂ Cl ₂ / EtOAce, 15:1) to afford scopoletin ( 8 ) (3.1 mg) ( _Rf = 0.39). Fr. A4-3 (192 mg) was purified by preparative TLC (silica gel, CH ₂ Cl ₂ /acetone, 5:1) to afford aesculetin ( 7 ) (3.9 mg) ( _Rf = 0.46). F. Fr. A6 (8.2 g) was separated by column chromatography eluting with CH ₂ Cl ₂ /EtOAc (10:1) to give a total of 7 divisions (each 1 L, Fr.A6-1~Fr .A6-7). Fr. A6-4 (180 mg) was purified by preparative TLC (silica gel, n- hexane/EtOAc, 2:1) to afford aesculetin dimethyl ester ( 10 ) (1.5 mg) ( _Rf = 0.71). Fr. A6-7 (28 mg) was purified by preparative TLC (silica gel, CHCl ₃ /MeOH 8:1) to afford oleoside methyl ester ( 6 ) (4.5 mg) ( _Rf = 0.19). G. Fr. A9 (7.3 g) was separated by column chromatography and eluted with CH ₂ Cl ₂ /MeOH (7:1) to obtain 4 partitions (each 500 mL, Fr.A9-1~) Fr. A9-4). Fr.A9-2 (202 mg) to _{preparative TLC (silica gel, CHCl 3} / MeOH 7: 1) to give (8 E) -4 "- O -methylligstroside (1) (4.5 mg) (R f = 0.66 Fr.A9-4 (188 mg) was again separated by column chromatography and eluted with CHCl ₃ /MeOH (3:1) to give a total of 2 divisions (each 150 mL, Fr.A9-4-1) ~Fr.A9-4-2). Fr.A9-4-1 (210 mg) was purified by preparative TLC (silica gel, CHCl ₃ /MeOH, 4:1) to give 3 " ,4 " -di- O- methyldemethyloleuropein (3) (3.1 mg) (R f = 0.61) .Fr.A9-4-2 (205 mg) to _{preparative TLC (silica gel, CH 2} Cl 2 / MeOH, 5: 1) to give (8 E )-4 " - O -methyldimethylligstroside ( 2 ) (4.2 mg) (R _f = 0.55). H. Fr. A10 (6.8 g) was separated by column chromatography and eluted with CH ₂ Cl ₂ /MeOH (7:1) to obtain 4 partitions (each 700 mL, Fr.A10-1~) Fr.A10-4). Fr.A10-1 (200 mg) preparative TLC to _{(silica gel, CHCl 3 / MeOH} , 7: 1) to give (8 E) -ligstroside (4) (7.3 mg) (R f = 0.65). Fr. A10-2 (180 mg) was purified by preparative TLC (silica gel, CH ₂ Cl ₂ /acetone 1:2) to afford oleuropein ( 5 ) (3.6 mg) ( _Rf = 0.35). A new cracked iridoid oxime extracted from ash tree: A new cracked iridoid oxime extracted from ash tree: A new cracked iridoid oxime extracted from ash tree: A biologically active ingredient extracted from ash tree, which has the potential to be developed as an anti-inflammatory lead drug, and the biologically active ingredient is as follows: A.(8 E )-4 " -O-Methylligstroside( 1 ) for formyl-L-methionyl-L -leucyl-L-phenylalanine/cytochalasin B (fMLP/CB) induces superoxide anion (O ₂ ^.- ) and elastase (elastase) in human neutrophils, with an IC ₅₀ value of 0.08. ±0.01 and 2.57±0.76 μg/mL. B.(8 E )-4 " - O -Methyldemethylligstroside( 2 ) has a good inhibitory effect on the production of superoxide anion (O ₂ ^.- ) induced by fMLP/CB in human neutrophils, with an IC ₅₀ value of 2.66 ± 0.33 μg/mL. C. 3 " , 4 " -di- O -Methyldemethyloleuropein( 3 ) has a good inhibitory effect on the production of superoxide anion (O ₂ ^.- ) induced by fMLP/CB in human neutrophils, with an IC ₅₀ value of 5.22 ± 2.34 μg/mL. D. Oleuropein ( 5 ) has a good inhibitory effect on the production of superoxide anion (O ₂ ^.- ) induced by fMLP/CB in human neutrophils, with an IC ₅₀ value of 2.90 ± 0.46 μg / mL. E. Aesculetin ( 7 ) has a good inhibitory effect on the production of superoxide anion (O ₂ ^.- ) and elastase (eastase) induced by fMLP/CB in human neutrophils, with IC ₅₀ values of 0.17±0.03 and 2.41, respectively. ±0.60 μg/mL. F. Isoscopoletin( 9 ) has a good inhibitory effect on the production of superoxide anion (O ₂ ^.- ) and elastase (eastase) induced by fMLP/CB in human neutrophils, with IC ₅₀ values of 5.20±1.52 and 3.23, respectively. ±0.68 μg/mL G. Fraxetin( 12 ) has a good inhibitory effect on the production of superoxide anion (O ₂ ^.- ) and elastase (eastase) induced by fMLP/CB in human neutrophils, with IC ₅₀ values of 0.19±0.01 and 0.50, respectively. ±0.10 μg/mL. H. Tyrosol ( 13 ) has a good inhibitory effect on the production of superoxide anion (O ₂ ^.- ) and elastase (eastase) induced by fMLP/CB in human neutrophils, with IC ₅₀ values of 4.93 ± 0.19 and 2.64, respectively. ±0.22 μg/mL. I. 4-Hydroxyphenethyl acetate( 14 ) has a good inhibitory effect on the production of superoxide anion (O ₂ ^.- ) and elastase (eastase) induced by fMLP/CB in human neutrophils, and its IC ₅₀ value is 2.50±. 0.35 and 3.03 ± 0.48 μg/mL. J.(+)-Pinoresinol( 15 ) has a good inhibitory effect on the production of superoxide anion (O ₂ ^.- ) by human neutrophils induced by fMLP/CB, and its IC ₅₀ value is 2.50±0.35 μg/mL.