Studies Of Chemical Constituents And Pharmacological Activities Of The Barks Of L.Chinense (Hemsl.) Sarg. X L.Tulipifera L.

Objective:The Liriodendron sp. genus belongs to Magnoliaceae. There are only two species now, L. tulipifera L. and L. chinense (Hemsl.) Sarg. In1963, Professor Peizhong Ye successfully cultured Liriodendron interspecific hybrids(L.chinense (Hemsl.) Sarg. x L. tulipifera L.) firstly in the word. As traditional medicine plant, Liriodendron sp. has many pharmacological activities. The foreign and domestic scholars have obtained more than forty aporphine alkaloids and several sequiterpenes from L. tulipifera L., but chemical constitutes and pharmacological activities of L. chinense and their hybrids have rarely been reported to date. To determine the bio-active constituents and their pharmacological activities, we studied the components of the barks of Liriodendron hybrids through the methods of extraction, purification and elucidation, and their bioactivities were also investigated in the end.Method:The95%EtOH extract of Liriodendron hybrids was partitioned with n-hexane, dichloromethane, EtOAc, actone, methanol to give five fractions, successively. The chemical constituents in n-hexane and dichloromethane partitions were isolated by means of silical gel/C18column chromatography, Sephadex LH-20. Their chemical structures were elucidated by MS, NMR, and chemical synthsis. The bioactivities of multi-partitions and phytochemicals were investigated by MTS antitumor model, Quorum sensing (QS) inhibition model and biofilm inhibition model, respectively.Result:thirteen phytochemical were isolated, and identified by the spectrum technology and chemical synthesid as5,6,7-trimethoxycoumarin (I),6,7-dimethoxycoumarin (â…¡),5-hydroxyl-6,7-dimethoxycoumarin (III),7-hydroxyl-6-methoxycourmarin (IV), N-phenethylbenzamide (V), N-(1-hydroxy-1-phenylethyl)-benzamide (VI), Lysicamine (VII), O-Methylmoschatoline (VIII), Oxopboebine (IX), N-acetylnornuciferine (X), Liriodenine (XI), N-Acetylasimilobine (XII), Tulipinolide (XIII). Mostly, chemicals (V) and (VI) were synthesized to confirm their structures. All of these chemicals were isolated from the species first time. In the end, some chemicals and the dichlormethane fraction showed antitumor, QS inhibitor and biofilm inhibitor activities.