[Phenolic constituents from stems of Ilex asprella].

Phytochemical investigation on Ilex asprella stems by using various chromatographic techniques led to the isolation of 18 phenolic constituents. Based on spectroscopic data analyses and/or comparison of the spectroscopic data with those in literature, these constituents were identified, including two lignans (1, 2), five phenylpropanes (3-7), six chlorogenic analogues (8-13), and five benzoic analogues (14-18). Among them, compounds 3-7, 9, 11, 13, 14, 17, and 18 were isolated from genus Ilex for the first time, and 2, 8, 10, 15, and 16 were isolated from this species for the first time. The in vitro anti-inflammatory assay results showed that compounds 8, 9, 11, 13, and 15 possessed moderate inhibition on the NO production in RAW264.7 cells with IC50 values of 51.1-85.8 µmol·L⁻¹. The present study brought preliminary reference for the clarification of therapeutic ingredients of I. asprella with anti-inflammatory efficacy and its quality evaluation.

Ahmpatinin iBu, a new HIV-1 protease inhibitor, from Streptomyces sp. CPCC 202950.

Ahmpatinin iBu (1) and statinin iBu (2), two new linear peptides, a novel pyrrolidine derivative, (-)-(S)-2-[3-(6-methylheptanamido)-2-oxopyrrolidin-1-yl] acetic acid (3), and three known pepstatin derivatives (4-6) along with their corresponding methanolysis artifacts (7-9) were isolated from Streptomyces sp. CPCC 202950. Their structures were elucidated on the basis of extensive spectroscopic data using Marfey's analysis, chiral-phase HPLC, and ECD and OR calculation to determine the absolute configurations. Compound 1 contains an unusual amino acid, 4-amino-3-hydroxy-5-(4-methoxyphenyl)pentanoic acid (Ahmppa), and 3 is the first natural product with a 2-(3-amino-2-oxopyrrolidin-1-yl)acetic acid system. Compounds 1, 2, and 4-9 are HIV-1 protease inhibitors. In particular, ahmpatinin iBu (1) exhibits significant inhibitory activity against HIV-1 protease with an IC50 value of 1.79 nM. A preliminary structure-activity relationship is discussed.

[Chemical constituents from stems of Ilex asprella].

Phytochemical investigation on the stems of Ilex asprella by using various chromatographic techniques led to the isolation of 13 compounds. By spectroscopic analyses and comparisons the spectral data with those in literatures, these compounds were identified as salicifoneoliganol(1), rel-(7R,8S)-3,3',5-trimethoxy-4',7-epoxy-8,5'-neolignan-4,9,9'-triol 9-ß-D-glucopyranoside(2),(+)-cycloolivil(3),(+)-syringaresinol-4'-O-ß-D-monoglucoside(4), liriodendrin(5), caffeic acid (6), 3,4-dihydroxy-5-methoxybenzaldehyde(7), benzene-1,2,4-triol(8), 3,4,5-trimethoxyphenyl-1-O-ß-D-apiofuranosyl(1″→6')-glucopyranoside(9), aeculetin(10), cryptochlorogenic acid ethyl ester(11), chlorogenic acid ethyl ester(12), and rel-5-(3S,8S-dihydroxy-1R,5S-dimethyl-7-oxa-6-oxobicyclo [3,2,1]oct-8-yl)-3-methyl-2Z,4E-pentadienoic acid(13). Among them, compounds 7, 8, 11, and 13 were isolated from genus Ilex for the first time, and 1-3, 9, 10, and 12 were isolated from this speciesfor the first time. The anti-inflammatory assay results of these compounds showed that compounds 1 and 9 showed moderate inhibitory effect against NO production in RAW 267. 4 cells with IC50 values of 35.7 and 50.6 µmol•L⁻¹, in vitro respectively, whereas compound 10 showed weak inhibition(IC50 value 98.7 µmol•L⁻¹).

[A phytochemical and pharmacological advance on Ilex asprella].

Ilex asprella is one of representative medicinal plants in South of the Five Ridges of China. The roots and rhizomes of I. asprella have the effects of clearing heat and detoxifying, stimulating salvia, and reducing thirst, which has been used to treat wind-heat cold, acute and chronic pharyngitis, and sore throat. Contemporary studies showed that I. asprella contains the major triterpenoids and glycosides, phenolic acids, and minor steroids. The extracts and compounds show activities of anti-inflammatory, antiviral, anti-tumor, and regulating lipid metabolism.The present paper summarizes a phytochemical and pharmacological advance on this species to provide reference for clarification of its pharmacologically active ingredients, quality evaluation, and further explorations.

[A new benzamide derivative from rice fermentation of Streptomyces sp. CPCC 202950].

Eight compounds were isolated from the rice fermentation of Streptomyces sp. CPCC 202950 by a combination of various chromatographic techniques including column chromatography over silica, Sephadex LH-20, flash C18, and reversed-phase HPLC. Their structures were identified as 3-[(3'-amino-3'-oxoprop-1'-en-2'-yl)oxy]benzamide (1), m-hydroxybenzamide (2), leptosphaepin (3), 5-methyluracil (4), feruloylamide (5), p-hydroxyphenylacetoamide (6), vanillamide (7), cyclo (L-val-L-ala) (8). Among them, 1 was a new benzamide analogue, and 2 was a new natural product. In the preliminary assays, none of the compounds 1-8 exhibited obvious inhibition of HIV-1 protease activity, and toxic with the Hela, HepG2, and U2OS cells. (IC50 > 10 µmol•L⁻¹).

Phenolic constituents from Rheum nobile and their antioxidant activity.

Although the rhizomes of Rheum nobile Hook. f. et Thoms (Polygonaceae) are widely used in Tibetan medicine, no previous investigations regarding the biological activities and rarely chemical constituents of this plant have been reported. As part of an ongoing search for novel bioactive agents, a phytochemical investigation of R. nobile led to the isolation of two new compounds Rheumone B (1) and piceatannol-4'-O-ß-D-(6″-O-acetyl)-glucoside (2), together with 15 known compounds by gel filtration over Sephadex LH-20 and preparative HPLC. Their structures were determined by combined spectroscopic methods. Compounds 1-10 were evaluated for their ability to scavenge 2,2-diphenyl-1-picrylhydzyl (DPPH) radical and compounds 7-10 showed relatively strong scavenging abilities with IC50 values from 2.76 µM to 11.80 µM. In conclusion, naphthalene glycosides, stilbene glycosides, flavanols, especially anthraquinones are main chemical constituents of this plant. The ability to scavenge DPPH radical of compound 8 was the highest among compounds 1-10.

Anti-Influenza Virus (H5N1) Activity Screening on the Phloroglucinols from Rhizomes of Dryopteris crassirhizoma.

For screening the active phloroglucinols on influenza virus (H5N1) from Dryopteris crassirhizoma NaKai, a database was established including twenty-three phloroglucinols that had been isolated from Dryopteris crassirhizoma. Their inhibitory effect on the neuraminidase (NA) of influenza virus H5N1 was screened by molecular docking. As a result, three candidates were selected. The rhizomes of D. crassirhizoma were subjected to isolation and purification processes to obtain the inhibitor candidates. Thirteen phloroglucinols were obtained, including three selected candidates and two new phloroglucinols. The five phloroglucinols were investigated for their inhibitory activity on NA in vitro. The results showed that dryocrassin ABBA and filixic acid ABA exhibited inhibitory effects on NA with IC50 as 18.59 ± 4.53 and 29.57 ± 2.48 µM, respectively, and the other three phloroglucinols showed moderate inhibitory activity. Moreover, the anti-influenza virus (H5N1) activity and cytotoxicity of dryocrassin ABBA and filixic acid ABA were tested on Madin-Darby canine kidney (MDCK) cells with the cell counting kit-8 (CCK8) method. The results confirmed that dryocrassin ABBA exhibited an inhibitory activity with low cytotoxicity (TC50 > 400 µM) against influenza virus (H5N1) which will have to be investigated in further detail. In conclusion, phloroglucinols from D. crassirhizoma were shown to have anti-influenza virus activity, and especially dryocrassin ABBA, one of the phloroglucinols, may have the potential to control influenza virus (H5N1) infection.

[Chemical Constituents of Salvia grandifolia].

Objective: To study the chemical constituents of Salvia grandifolia. Methods: The chemical constituents were isolated and purified by means of chromatographic techniques and their structures were elucidated by spectroscopic methods. Results: Eleven compounds were isolated from chloroform and ethyl acetate of ethanol extract, and identified as tanshinone Ⅵ( 1),tetrahydrotanshiquinone( 2),tanshinone ⅡB( 3),danshenol B( 4), ursolic acid( 5),2α-hydroxyursolic acid( 6),2α,3α-dihydroxyurs-12-en-28-oic acid( 7),salvianolic acid B(8),3,5-dihydroxycinnamic acid( 9),ethyl 3-( 3,4-dihydrophenyl) lactate( 10) and nepetoidin B( 11). Conclusion: All of them are isolated from this plant for the first time.