No abstract

The Araliaceae plant, Panax (P.) quinquefolium L., which is called as American ginseng or North American ginseng, is widely cultivated in U.S.A., Canada, and China. The roots of this plant are used for the same medicinal purposes as Ginseng, the roots of P. ginseng C. A. MEYER. The biologically active constituents of the roots have been pursued extensively and many dammarane-type triterpene oligoglycosides have been characterized as the principal ingredients.2-6) On the other hand, the flower buds of P. quinquefolium have been used as an exhilarant and tonic in the form of health tea. However, chemical and pharmacological studies on the bioactive constituents from the flower buds were yet left uncharacterized. Recently, we have reported the isolation and structure elucidation of dammarane-type triterpene oligoglycosides from the flower buds of P. ginseng 1,7,8) and P. notoginseng.9) Among them, ginsenoside Rd, which is principal constituent from the flower buds of P. ginseng, was found to show gastroprotective effect and ginsenosides-Rb 3 (6) and Rc, which are principal constituents from the flower buds of P. notoginseng, were found to show hepatoprotective effects. As a continuing study on the bioactive constituents of medicinal flowers, 1,[7][8][9][10][11][12][13][14][15] we have isolated new dammarane-type triterpene glycosides named floralquinquenosides A (1), B (2), C (3), D (4), and E (5) from the flower buds of P. quinquefolium together with 18 known dammarane-type triterpene oligoglycosides and three flavonoid glycosides. In this paper, we describe the isolation and structure elucidation of new floralquinquenosides (1-5).Isolation of Floralquinquenosides The methanolic extract from the flower buds of P. quinquefolium cultivated in Jilin province of China was partitioned into an ethyl acetate (EtOAc)-water mixture to furnish an EtOAc-soluble portion and an aqueous layer. The aqueous layer was further extracted with n-butanol (n-BuOH) to give an n-BuOH-soluble portion. The EtOAc-soluble fraction was subjected to normal-phase and reversed-phase silica gel column chromatography and finally HPLC to afford floralquinquenoside A (1, 0.0015% from the dried flower buds) together with 11 known compounds, ginsenoside Rb 3 (6,9,16) -rhamnopyranoside (26, 22) 0.0018%). The n-BuOH-soluble portion was subjected to normal-phase and reversed-phase silica gel column chromatography and finally HPLC to afford floralquinquenosides B (2, 0.0011%), C (3, 0.0036%), D (4, 0.0046%), and E (5, 0.0062%) together with 18 known compounds, ginsenoside Rb 3 (6, 9,16) 0.11%), ginsenoside Rd (7, 17) 0.23%), ginsenoside Rs 1 (8,18) 0.034%), pseudo-ginsenoside-RC 1 (9, 23) 0.0096%), pseudo-ginsenoside-F 8 (10, 18) 0.030%), quinquenoside III (11,2) (20,20) 0.0066%), pseudo-ginsenoside F 11 (21,20) 6.1%), 24(S)-pseudo-ginsenoside F 11 (22,20) 0.015%), and kaempferol 3-O-b-D-sophoroside-7-O-a-Lrhamnopyranoside (24, 27) 0.0042%).

As a part of our characterization studies on the bioactive saponin constituents of tea ‰owers (Camellia sinensis, ‰ower buds), the methanolic extract and 1-butanol-soluble portion (the saponin fraction) from the ‰ower buds were found to exhibit potent inhibitory eŠects on ethanol-and indomethacin-induced gastric mucosal lesions in rats and on serum glucose elevation in sucrose-loaded rats. Among the constituents of the 1-butanol-soluble portion, ‰oratheasapo-nins A, B, and C showed gastroprotective and hypoglycemic activities. Furthermore, we have developed qualitative and quantitative methods using HPLC for the principle saponins, ‰oratheasaponins A F, in tea ‰owers, which were previously found to show antiallergic and antiobesity eŠects. Using those methods, the saponin composition of Indian tea ‰owers were found to be similar to those of Chinese (Anhui) but not of Japanese tea ‰owers. On the other hand, it was found that the ‰oratheasaponin contents in tea ‰owers varied markedly during the blooming period, and they were abundant at half-bloom. Additionally, the contents of caŠeine in the tea ‰owers were examined using HPLC.

The Legminosae plant, Psoralea corylifolia L., is widely distributed from India to Southeast Asian countries. The seeds of this plant have been used as a tonic, to treat uterine hemorrhage, and as a coronary vasodilatory agent in Chinese traditional medicine. [2][3][4][5] Previously, several meroterpenoid [6][7][8][9][10][11] and flavonoid [12][13][14][15][16][17][18][19] constituents were isolated from this natural medicine. In addition, biological studies to determine its antioxidative, 20) antiplatelet, 21) and DNA polymerase and topoisomerase II inhibitory activities 22) were also reported. In the course of our characterization studies on the bioactive constituents in Chinese natural medicines, 1,[23][24][25][26][27][28][29][30][31][32][33][34] the ethyl acetate (EtOAc)-soluble fraction of the methanolic extract from this natural medicine was found to inhibit antigen-IgE-induced degranulation in RBL-2H3 cells. From this active fraction, two meroterpene constituents (1, 2) 35) were newly isolated together with 14 known constituents. This paper deals with the isolation and structural confirmation of the two compounds (1, 2) as well as the inhibitory effects of the constituents from P. corylifolia on antigen-induced degranulation in RBL-2H3 cells.The seeds of P. corylifolia were extracted with methanol under reflux. The methanolic extract was partitioned into an EtOAc-H 2 O (1 : 1, v/v) mixture to furnish the EtOAc-and H 2 O-soluble fractions. The EtOAc-acetate-soluble fraction inhibited antigen-induced degranulation in RBL-2H3 cells [inhibition (%): 39.3Ϯ2.5 (pϽ0.05) at 30 mg/ml], but the H 2 O-soluble fraction did not [inhibition (%): 6.3Ϯ4.4 at 30 mg/ml]. The EtOAc-soluble fraction was subjected to ordinary and reverse-phase silica gel column chromatography and finally HPLC to furnish 1 (0.011% from the natural medicine), 2 (0.009%), bakuchiol 6-10) (3, 8.19%) [d 6.75, 7.21 (2H each, both d, Jϭ8.5 Hz,11,13,10,]. As shown in Fig. 1, the 1 H-1 H correlation spectroscopy ( 1 H-1 H COSY) experiment on 1 indicated the presence of partial structures in bold lines. In the heteronuclear multiple-bond correlations (HMBC) experiment on 1, long-range correlations were observed between the following protons and carbons (1-H 3 , 18-H 3 and 2-C; 1-H 3 , 2-H, 4-H 2 , 7-H, 8-H, 18-H 3 and 3-C; 2-H and 4-C; 15-H 3 and 5-C; 5-H 2 , 7-H 2 , 15-H 3 , 16-H, 17-H 2 and 6-C; 15-H 3 and 7-C; 10,14-H and 8-C; 8-H, 11,13-H and 9-C; 8-H and 10,14-C; 10,14-H and 12-C; 16-H and 15-C; 15-H 3 and 16-C), as shown in Fig. 1. Thus the connectivities of quaternary carbons (3, 6, 9, 12-C) in 1 were clarified and the planar structure of 1 was elucidated. Next, the stereostructure of 1 was characterized in a nuclear Overhauser enhancement spectroscopy (NOESY) experiment, which showed NOE correlations between the following proton pairs (4b-H, 5b-H and 15-H 3 ; 7a-H and 10,14-H, 15-H 3 , 16-H; 8-H and 10,14-H, 15-H 3 ), as shown in Fig. 1 The

The MeOH extract and its BuOH-soluble fraction (crude saponin fraction) from the flower buds of Chinese tea plant (Camellia sinensis (L.) O. KUNTZE; Fujian Province) were found to exhibit accelerating effects on gastrointestinal transit in mice and inhibitory effects against pancreatic lipase. From the BuOH-soluble fraction, three new acylated oleanane-type triterpene oligoglycosides, chakasaponins I, II, and III (1-3, resp.), were isolated together with 13 known compounds. The chemical structures 1-3 were elucidated on the basis of chemical and physicochemical evidence. Compounds 1-3 showed accelerating effects on gastrointestinal transit in mice and inhibitory effects against porcine pancreatic lipase (IC(50)=150-530 microM).