阅读说明：本技术 一种新的肉桂酰酯儿茶素及四种新的苯丙素黄烷生物碱制备和应用 (Preparation and application of novel cinnamoyl ester catechin and four novel phenylpropanoid flavane alkaloids ) 是由 鲍官虎 柯家平 拉什米·高尔 于 2020-02-12 设计创作，主要内容包括：本发明属于化学技术领域,具体涉及一种新的肉桂酰酯儿茶素及四种新的苯丙素黄烷生物碱及其制备方法。本发明在制备上述苯丙素儿茶素时,首先将表儿茶素、肉桂酰氯、三氟乙酸及四氢呋喃,在室温下搅拌24小时,收集乙酸乙酯溶液,取部分分离纯化得到3-O-肉桂酰基-表儿茶素。再将茶氨酸与3-O-肉桂酰基-表儿茶素加热反应,收集甲醇部分,在进行分离纯化得到四种儿茶素衍生物,通过乙酰胆碱酯酶抑制实验中发现,得到的5种化合物在抑制乙酰胆碱酯酶上有显著的功效,具有开发成抗阿尔茨海默病药物的潜力。同时5种化合物在抗疟实验中也有一定功效,具有开发成抗疟疾药物的潜力。本发明中的制备方法简单环保,成本较低。(The invention belongs to the technical field of chemistry, and particularly relates to novel cinnamoyl ester catechin, four novel phenylpropanoid flavane alkaloids and a preparation method thereof. When the phenylpropanoid catechin is prepared, firstly, epicatechin, cinnamoyl chloride, trifluoroacetic acid and tetrahydrofuran are stirred for 24 hours at room temperature, an ethyl acetate solution is collected, and part of the ethyl acetate solution is separated and purified to obtain 3-O-cinnamoyl-epicatechin. And then heating theanine and 3-O-cinnamoyl-epicatechin to react, collecting a methanol part, and separating and purifying to obtain four catechin derivatives, wherein the result of an acetylcholinesterase inhibition experiment shows that the obtained 5 compounds have a remarkable effect on inhibiting acetylcholinesterase and have the potential of developing anti-Alzheimer disease drugs. Meanwhile, the 5 compounds have certain efficacy in antimalarial experiments and have the potential of being developed into antimalarial drugs. The preparation method is simple and environment-friendly, and has low cost.)

1. A novel cinnamoyl ester catechin and four novel phenylpropanoid flavan alkaloids, characterized by having the following structural formula I-V:

2. a process for the preparation of a novel cinnamoyl ester catechin and four novel phenylpropanoid flavan alkaloids according to claim 1, comprising the steps of:

1) preparation of 3-O-cinnamoyl-epicatechin

The compound shown in the formula (I) is obtained by the reaction of epicatechin and cinnamoyl chloride;

2) preparation of phenyl propanoid flavane alkaloid

A. Reacting theanine with 3-O-cinnamoyl-epicatechin under heating to obtain compounds shown in (II) - (V);

B. isolation of Compounds represented by (II) to (V)

And D, separating and purifying the product obtained in the step A to obtain the phenylpropanoid flavane alkaloids shown in formulas (II) - (V) respectively.

3. The process of claim 2 for the preparation of a novel cinnamoyl ester catechin and four novel phenylpropanoid flavan alkaloids, wherein: the epicatechin and the cinnamoyl chloride in the step 1) are obtained by reaction under the catalysis of trifluoroacetic acid.

4. The process of claim 2 for the preparation of a novel cinnamoyl ester catechin and four novel phenylpropanoid flavan alkaloids, wherein: step 2) the heating reaction temperature of theanine and 3-O-cinnamoyl-epicatechin is 100 ℃.

5. The method for preparing the novel cinnamoyl ester catechin and the four novel phenylpropanoid flavan alkaloids according to claim 3 or 4, wherein the separation and purification in step 3) is to dissolve the product obtained in step 2) A, sequentially perform Sephadex L H-20 gel column chromatography and Toyopearl column chromatography, and finally perform HP L C separation and purification to obtain the four phenylpropanoid flavan alkaloids.

6. The process for preparing the novel cinnamoyl ester catechin and the four novel phenylpropanoid flavan alkaloids according to claim 3, wherein the separation and purification step in step 3) comprises dissolving the obtained product in aqueous methanol, performing Sephadex L H-20 gel column chromatography, and performing MeOH-H gel column chromatography₂Performing gradient elution with the volume ratio of O being 20:80 to 100:0, and collecting MeOH-H in the gradient elution₂Elution components in a volume ratio of O of between 30:70 and 80: 20; subjecting the obtained fraction to Toyopearl column chromatography with MeOH-H₂Performing gradient elution with the volume ratio of O being 20:80 to 100:0, and collecting MeOH-H in the gradient elution₂And (3) eluting components with the volume ratio of O of 60:40 to 100:0, collecting fractions of L per 20m, combining collected fractions on a plate, evaporating to dryness, collecting corresponding components, and purifying by using HP L C to obtain the compounds with the structural formulas (II) - (V).

7. The use of a compound of formula i-v as defined in claim 1 in an anti-alzheimer's disease medicament.

8. Use of a compound of formula i-v according to claim 1 in antimalarial drugs.

Technical Field

The invention belongs to the technical field of chemistry, and particularly relates to novel cinnamoyl ester catechin, four novel phenylpropanoid flavane alkaloids, and a preparation method and application thereof.

Background

Tea belongs to the Theaceae family, is one of three non-alcoholic beverages in the world, and has been popular with consumers in the past and today. With the improvement of living standard of people, the health problem is more and more emphasized. The health care function of tea leaves is also receiving wide attention. Researches prove that the tea has multiple effects of resisting oxidation, resisting aging, reducing blood sugar, reducing blood fat, losing weight and the like. The health efficacy of the tea is related to the active ingredients contained in the tea. At present, researches on active ingredients of tea leaves are reported continuously, active ingredients such as polyphenols, flavonoids, alkaloid compounds and the like in the tea leaves are gradually discovered, and the biological activities of the active ingredients are continuously researched and researched.

Tea polyphenols are the most main secondary metabolites existing in tea, and mainly comprise catechin, flavonoid, anthocyanin, phenolic acid, depside, etc. Wherein the catechin accounts for about 70% of total amount of tea polyphenols, and mainly comprises four kinds of catechin including Epicatechin (EC), gallocatechin (EGC), epicatechin gallate (ECG) and epigallocatechin gallate (EGCG). Researches show that catechin in tea mainly has the health-care effects of inhibiting bacteria, preventing cancer, resisting oxidation, reducing blood pressure, resisting diabetes, inhibiting activity of renin and the like. With the rapid development of scientific technology, natural product technology is continuously and deeply applied to phytochemicals, researchers successively separate phenylpropanoid catechins and derivatives thereof from some plants, and experiments prove that the activity effect of a plurality of catechin derivatives is better than that of the catechins. The discovery of phenylpropanoid catechin and flavan alkaloid with bioactivity will make important contribution to the fields of agriculture and medicine.

Disclosure of Invention

One of the purposes of the invention is to provide a new cinnamoyl ester catechin and four new phenylpropanoid flavan alkaloids, wherein the phenylpropanoid catechin and the flavan alkaloids have the following structures:

another object of the present invention is to provide a method for preparing the above-mentioned novel cinnamoyl ester catechin and four novel phenylpropanoid flavan alkaloids, which comprises the following steps:

1) preparation of 3-O-cinnamoyl-epicatechin

The compound shown in the formula (I) is obtained by the reaction of epicatechin and cinnamoyl chloride;

2) preparation of phenyl propanoid flavane alkaloid

A. Reacting theanine with 3-O-cinnamoyl-epicatechin under heating to obtain compounds shown in (II) - (V);

B. isolation of Compounds represented by (II) to (V)

And D, separating and purifying the product obtained in the step A to obtain the phenylpropanoid flavane alkaloids shown in formulas (II) - (V) respectively.

Preferably, the reaction temperature of the theanine and the 3-O-cinnamoyl epicatechin in the step 2) is 100 ℃.

Preferably, the separation and purification in the step 3) is to dissolve the product, sequentially perform Sephadex L H-20 gel column chromatography, Toyopearl column chromatography and HP L C preparation, separation and purification to obtain the four phenylpropanoid flavane alkaloids.

Preferably, the separation and purification step in step 3) is carried out by dissolving the product in methanol water solution, and then carrying out Sephadex L H-20 gel column chromatography with MeOH-H₂Performing gradient elution with the volume ratio of O being 20:80 to 100:0, and collecting MeOH-H in the gradient elution₂Elution components in a volume ratio of O of between 30:70 and 80: 20; subjecting the obtained fraction to Toyopearl column chromatography with MeOH-H₂Performing gradient elution with the volume ratio of O being 20:80 to 100:0, and collecting MeOH-H in the gradient elution₂And (3) eluting components with the volume ratio of O of 60:40 to 100:0, collecting fractions of every 20m L, combining collected fractions on a plate, evaporating to dryness, collecting corresponding components, and finally preparing and purifying by using HP L C to obtain the components (II) - (V).

The invention has the beneficial effects that:

1. the phenylpropanoid flavane alkaloid provided by the invention has the effect of inhibiting acetylcholinesterase (AChE), can be used for preparing a medicament for preventing Alzheimer's disease, has an obvious effect in an antimalarial experiment, can be used for preparing an antimalarial medicament, has an important significance in the fields of agriculture and medicine, and provides a wider prospect for effectively developing and utilizing tea leaves.

2. The preparation method of the phenylpropanoid flavane alkaloid has the advantages of simple process, easy implementation, lower cost and very good application prospect.

3. The method for detecting the phenylpropanoid flavane alkaloid has simple process, easy implementation and high accuracy, can be used for searching biological resources containing the phenylpropanoid flavane alkaloid, increases the acquisition path of the phenylpropanoid flavane alkaloid and improves the utilization rate of the phenylpropanoid flavane alkaloid.

Drawings

FIG. 1 is a chemical structural formula of five novel compounds of the present invention;

FIG. 2 is a reaction sequence for synthesizing five novel compounds according to the present invention;

FIG. 3(A) is a diagram of a total ion flow of tea leaves, an extracted EIC and five compound mass spectrograms;

FIG. 3(B) is the fragment ion peak of the compound;

FIG. 3(C) is a putative cleavage pathway of the ion peak of the fragment of the compound;

FIG. 3(D) is a secondary mass spectrum of five compounds;

FIG. 4(A) is a CD reciprocal difference plot for compounds II and III;

FIG. 4(B) is a CD reciprocal difference plot for compounds IV and V.

Detailed Description

The experimental procedures in the following examples are conventional unless otherwise specified.

The percentages in the following examples are by mass unless otherwise specified.

The present invention will be described in further detail with reference to specific examples.