Synthetic method for scutellarein

Abstract

The invention provides a synthetic method for scutellarein. The synthetic method comprises the following steps: subjecting a compound with a structure as shown in a formula (I) which is described in the specification to oxidative ring-closure to produce a compound with a structure as shown in a formula (2-8) which is described in the specification; and subjecting the compound with a structure as shown in the formula (2-8) to demethylation so as to produce a target compound as shown in a formula (1-2) which is described in the specification, wherein R in the formula is selected from a group consisting of C2-C5 alkylacyl groups which are unsubstituted or substituted by any one phenyl group, and benzoyl groups which are unsubstituted or arbitrarily substituted by C1-C5 alkyl groups. The synthetic method is simple in process, mild in conditions, and high yield, wherein the overall yield of the method is as high as 80.4%; and the synthetic method has good industrial application prospects.

Description

technical field [0001] The invention relates to the total synthesis of active ingredients of natural medicines, in particular to a synthesis method of scutellarin aglycon. Background technique [0002] Erigeron breviscapus, commonly known as breviscapus, is the dry whole herb of Erigerm breviscapus (Vant.) Hand-Mass, a plant of the Compositae family. Bitter in taste, warm in nature, can cure rheumatism pain". "Yunnan Chinese Herbal Medicine" clearly states that breviscapus is mainly used for dispelling cold, relieving the exterior, promoting blood circulation and relaxing tendons, cold, headache, nasal congestion, bruises, etc. Breviscapine is a general term for the flavonoid active ingredients extracted from Breviscapus. The scutellarin medicines currently used clinically all use scutellarin as the main active ingredient, and its main pharmacological ingredient is scutellarin (1-1, Scutellarin, also known as scutellarin, molecular formula: C 21 h 18 o 12 , molecular we...

AI Technical Summary

Problems solved by technology

The problems of extracting scutellarin from plants are: (1) planting scutellaria takes up a lot of land resources, and the quality of the product is greatly affected by the environment; (2) the content of scutellarin in scutellaria is low, resulting in the extraction The rate is low and the cost is high; (3) the quality of extraction is not stable

However, the disadvantage is that raw materials (1-4) are not easy to prepare (obtained as raw materials from 1-5), and the price is expensive

[0029] Analyzing the above synthesis route of scutellarin (1-1), there are several disadvantages as follows: (1) The use of protecting group strategy obviously increases the difficulty of reaction route and experimental operation; (2) Debenzylation needs to use 0.25 The equivalent Pd / C greatly increases the cost; (3) in the glycosylation reaction, Ag 2 O needs to use 1-2 equivalents, the cost is high

The existing problems in the total synthesis route of scutellarin are as follows: (1) Most of the synthetic routes of key intermediate scutellarin aglycon use compound (1-5) as raw material, while compound (1-5) There are problems such as low yield, serious pollution or difficult operation in the synthesis, which is also the key problem in the current scutellarin total synthesis process; (2) scutellarin aglycone (1-2) can be obtained from scutellarin through 5-step reaction Scutellarin, the route is long, and a large amount of expensive reagents are used, the production cost is too high, and it is not suitable for the large-scale preparation of scutellarin

Images