[Study on quality evaluation of Dihuang (Rehmannia glutinosa) by two-dimension HPLC fingerprints and chemometrics methods].

The study is to establish the two-dimension HPLC fingerprints of Dihuang (Rehmannia glutinosa), by HPLC-PDA and HPLC-ELSD methods. The separations were performed on Waters Atlantis®T3（4.6 mm× 250 mm，5 µm）and Welch Ultimate®Hilic-NH2（4.6 mm× 250 mm，5 µm）columns with the gradient elution of acetonitrile-0.01% phosphoric acid and acetonitrile-water, respectively. The chromatographic display wavelength for PDA detector was set at 203 nm. For HPLC-ELSD, the nebulizer was set as cooling mode, the drift tube temperature was set at 60 °C and the gas pressure was 35.0 psi. Based on similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine, 26 and 10 chromatographic peaks were determined as common components for HPLC-PDA and HPLC-ELSD fingerprints, respectively. Chemometrics analyses, such as similarity analysis; cluster analysis and principal component analysis, were performed on the common peak areas in two-dimension fingerprints for 41 batches of Dihuang from multiple sources. The results showed that the HPLC-PDA fingerprint could distinguish dried rehmannia root between different sources, and HPLC-ELSD fingerprint could differentiate dried rehmannia root from prepared rehmannia root. The two-dimension fingerprints were established with advantages of a good degree of separation, abundant chemical information and multi-components identified including two nucleosides (adenosine and uridine)，four iridoid glycosides (catalpa alcohol，rehmaionoside D，rehmaionoside A and leonuride)，two phenylethanoid glycosides (acteoside and cistanoside A) and nine sugars. The method is simple and practical, which could be used for the identification and quality assessment for Dihuang.

Two new phenolic compounds from the tuber of Sparganium stoloniferum.

Two new phenolic compounds, 2-(2-hydroxyphenyl)-4-methoxycarbonyl-5-hydroxybenzofuran (1) and 1-methoxycarbonyl-2, 3-dihydroxydibenzo[b, f]oxepine (2), were isolated from the tuber of Sparganium stoloniferum. The structures of both new compounds were determined on basis of spectroscopic means including HR-ESI-MS, 1D and 2D NMR experiments.

[Caffeoyl phenylethanoid glycosides from Callicarpa kwangtungensis].

Phytochemical investigation on the EtOH extract from the aerial part of Callicarpa kwangtungensis led to the isolation and characterization of 10 caffeoyl phenylethanoid glycosides, 2'-acetylacteoside (1), tubuloside E (2), acteoside (3), tubuloside B (4), isoacteoside (5), alyssonoside (6), 2'-acetylforsythoside B (7), brandioside (8), forsythoside B (9), and poliumoside (10). Compound 4 was isolated from the plants of Verbenaceae,and 6 was obtained from the Callicarpa genus, for the first time, while compounds 1, 2, 5 and 7 were firstly reported from the plant.

Four new constituents from the fruits of Cyclocodon lancifolius (Roxburgh) Kurz.

Phytochemical analysis of the fruits of Cyclocodon lancifolius led to the isolation of two new phenylpropanoid-derived glycosides (1-2), two new geranyl glucosides (3-4), and nine known compounds (5-13). Their chemical structures were elucidated by extensive spectroscopic data. The absolute configuration of the sugar moiety was determined by hydrolysis and derivatization. All compounds were evaluated for their xanthine oxidase (XO) and α-glucosidase inhibitory activities, and four compounds showed weak inhibitory activity towards XO.

Isoprenylated flavonoids from Morus nigra and their PPAR γ agonistic activities.

A novel dihydroflavonol unprecedentedly with a prenyl group at C-2, nigragenon A (1), four new sanggenon-type flavonones, nigragenons B-E (2-5), along with six known isoprenylated flavonoids (6-11) were isolated from the twigs of Morus nigra. Their structures were elucidated through extensive analysis of spectroscopic data. Interestingly, compound 1 was the first reported biogenetic precursor of sanggenon-type flavanones and the biogenetic pathway from 1 to sanggenol F was proposed. The PPAR γ agonistic activity was investigated in HEK293 cells using dual luciferase reporter assay. Compounds 2, 4, 7, and 9 showed obvious agonistic activities on PPAR γ, and compound 2 was a potential PPAR γ partial agonist. Moreover, the preliminary structure-activity relationships for the tested compounds were discussed.