Study on the Chemical Components of 8-O-4 ‘New Lignin in Physcomitrella chinensis
Mao Wei Zi is the fruit of Leonurus japonicus, a plant in the family Lamiaceae. The name “Yi Mu” was first recorded in Guangya: “Yi Mu, Mao Wei Ye”. As a medicinal herb, it was first recorded in Shennong Bencao Jing:; Previous generations often used a mixture of motherwort and wolfberry until the “Compendium of Materia Medica” recorded that “if the treatment of hand and foot Jueyin blood is divided into wind heat, clearing liver heat, improving vision and benefiting essence, regulating women’s meridians, then wolfberry alone is good. If the treatment of swelling, toxin, ulcers, dispelling water and promoting blood circulation, women’s fetal diseases, then it is advisable to use them together for good…” wolfberry and motherwort eventually developed into two independent traditional Chinese medicines, which are used for different clinical symptoms according to their respective advantages.
At present, there is a lot of research on the phytochemistry of motherwort, while there is little research on wolfberry. Very few compounds have been isolated from the seeds of Chinese wolfberry, mainly including triterpenes, steroids, cyclic peptides, and aromatic compounds. In addition, some literature used gas chromatography-mass spectrometry (GC-MS) to analyze its components, and found that Fructus Dioscoreae contains a large amount of aliphatic, monoterpenoid and other compounds. However, overall, research on the chemical composition of wolfberry is still relatively scarce. Fu Wei Zi is clinically used to treat menstrual disorders, amenorrhea, dysmenorrhea, postpartum blood stasis and abdominal pain, redness and swelling of the eyes, unclear vision, dizziness and bloating, and primary hypertension. Its pharmacological substance basis is still unknown. This experiment used modern separation methods to study the chemical composition of Fructus Ranunculi. Meanwhile, through literature review, it was found that such compounds have biological activities such as anti-tumor, anti-inflammatory, antiviral, hepatoprotective, and inhibition of platelet activating factor (PAF). Therefore, this experiment combined the traditional liver clearing effect of Fructus Polygonatum sibiricum to screen its anti liver cancer and liver cell protective activities, in order to clarify more theoretical basis for the traditional function of Fructus Polygonatum sibiricum.

In this experiment, the 8-O-4 ‘neolignans in Leonurus japonicus and their anti hepatoma and hepatocyte protective activities were studied. They were separated by silica gel, gel column chromatography and reverse phase medium pressure liquid chromatography, and then three 8-O-4’ neolignans were identified according to spectral data analysis. The absolute configuration of compound 1 was determined for the first time. Compound 3 is a new natural product, and compounds 1, 2 and 3 were isolated from Leonurus japonicus for the first time. This study enriches the types of chemical components in the Chinese wolfberry.
The relative configuration of 8-O-4 ‘new lignin compounds is mainly determined by the coupling constants of H-7 and H-8 in’ H NMR ‘. This method is derived from a pair of isomers and their acetylated products obtained by Wallis et al. through synthesis. The coupling constants of H-7 and H-8 in CDCI3 differ greatly, with the red form ranging from 2.5~3.5Hz and the Su form ranging from 6.8~8.4Hz. However, Gan et al. proposed that the influence of solvents must be considered when using this method. The absolute configuration confirmation method mainly relies on the FCD method, which is based on the synthesis of oxygen lignin analogues (2R, 3S) -3-methyl-2-phenyl-1,4-benzodioxane by Aroldi et al., which exhibit positive Cotton effect at 210-250nm. The compound 1 isolated in this article exhibits a positive Cotton effect at 228nm (Figure 2), and its absolute configuration is determined by comparing its optical rotation with compounds in the literature. In addition, this experiment used MTT assay to screen the inhibitory effect of the isolated compounds on SMMC-7721 liver cancer cells and their protective effect on HL-7702 and Chang liver cells induced by acetaminophen. At 50umol/L, none of the three compounds showed significant anti liver cancer and liver cell protective activity, but it cannot be concluded that lignin in Fructus Ranunculi has no anti liver cancer and liver cell protective activity. Researchers will continue to study its chemical composition in order to obtain more compound quantities and further seek the material basis for its liver clearing and vision improving effects.