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Biomedical subjects

Q T Zheng

Publications and source records attributed to Q T Zheng.

At least 19 recordsLinked to original sources
PubMed2001

Cytotoxic 7,20-epoxy ent-kauranoids from Isodon xerophilus.

Four 7,20-epoxy ent-kaurane diterpenoids, xerophilusins G (1) and I-K (2-4), were isolated from the leaves of Isodon xerophilus, along with four known ones, enanderianin C (5), rosthorin A (6), longikaurin B (7), and rabdoternin D (8). Their structures were determined primarily using NMR spectroscopic techniques. The structure and stereochemistry of 3 were confirmed by X-ray crystallography. Compounds 4 and 7 exhibited broad cytotoxicity against four kinds of human tumor cells (K562, HL-60, HCT, and MKN-28 cells) in the range of 2.23-15.35 and 0.30-8.61 microg/ml, respectively.

Antineoplastic Agents, Phytogenic↗
PubMed2001

A new sesquiterpene lactone from Tsoongiodendron odorum Chun.

A new sesquiterpene lactone (1) was obtained from the cytotoxic fraction of 95% ethanol extract of root barks of Tsoongiodendron odorum Chun together with two known sesquiterpene lactones, costunolide (2) and parthenolide (3). The structure of 1 was elucidated as 5alpha, 6alpha, 7beta, 10beta- 11alpha, 13-dihydro-4(15)-eudesmene-12, 6-olide on the basis of chemical and spectral evidence including X-ray diffraction analysis. Costunolide showed cytotoxic activity against human leukemia (HL-60) cell line. Parthenolide showed promising cytotoxic activities in vitro against HCT-8, Bel-7402, SKOV3, KB, HELA and EJ cell lines. Also, the cytotoxic ethyl acetate fraction of ethanol extract of the root barks from which three chemical components were isolated showed promising cytotoxic activities in vitro against KB, BGC-823, Bel-7402, HCT-8, HL-60 cell lines.

Antineoplastic Agents, Phytogenic↗
PubMed2000

Two novel secoergosterols from the fungus Tylopilus plumbeoviolaceus.

Two novel secoergosterols, 3beta-hydroxy-8alpha,9alpha-oxido-8, 9-secoergosta-7,9(11),22-triene (tylopiol A) (1) and 3beta-hydroxy-8alpha,9alpha-oxido-8,9-secoergosta-7,22 -dien-12-one (tylopiol B) (2), were isolated from the fresh fruit bodies of Tylopilus plumbeoviolaceus, along with three known compounds, ergosta-7,22-dien-3beta-ol, uridine, and allitol. Their structures were elucidated by NMR techniques, including (1)H NMR, (13)C NMR, HMQC, HMBC, and MS. The structure and stereochemistry of compound 1 were demonstrated by X-ray crystallography.

Agaricales↗
PubMed2000

[Selective isolation of isopsoralen from crude extract of Psoralea corylifolia. L by using inclusion method of host-guest molecules].

AIM: To isolate the chemical components from extracted crude of Psoralea corylifolia L. METHODS: Applicate the function of molecular recognition in supramolecular chemistry, use 1,1,6,6-tetraphenylhexa-2,4-diyne-1,6-diol as the host molecule and chemical components in extracted crude of Psoralea corylifolia L. as guest molecules, which represent different from either in sort, quantity and sites of function groups or in structural topological character, 1,1,6,6-tetraphenylhexa-2,4-diyne-1,6-diol could selectively form inclusion compound with component endowed with interactional complementarity and isolate as crystalline from the extracted crude of Psoralea corylifolia L. RESULTS: The isopsoralen as guest molecule is selectively included by 1,1,6,6-tetraphenylhexa-2,4-diyne-1,6-diol in inclusion crystal and removed by acetone from the inclusion compound and total yield is 0.18%. Isopsoralen is determined by UV, IR, 1HNMR and MS and its inclusion compound is determined by means of IR, powder XRD and single crystal XRD. The isolation effect is analyzed by GC/MS. CONCLUSION: The method is simple and selective for isolation isopsoralen from extracted crude of Psoralea corylifolia L.

Furocoumarins↗
PubMed2000

[X-ray diffraction Fourier pattern analysis of natural caculus bovis].

OBJECTIVE: To set up a method for analyzing and distinguishing all the chemical components in natural Caoulus Bovis. METHOD: Powder X-ray diffraction analyses was used to analyze four samples of natural Caculus Bovis, and the X-ray diffraction Fourier pattern was obtained for distinguishing natural Caculus Bovis. RESULT AND CONCLUSION: The method can be used for distinguishing animal medicinal materials.

Animals↗
PubMed1997

[Studies on X-ray diffraction pattern of traditional Chinese medicinal materials].

Traditional Chinese medicine(TCM) as prescribed by Chinese traditional physicians is usually available as "decoction slices" which calls for a ready method for assessment of quantity or even genuineness. Three groups of TCM drugs (radix Rubiae, bulbus Fritillariae and rhizoma Dioscoreae) were selected by using powder X-ray diffraction analysis with complete absorption profile. Topological regularity and characteristic peaks of the absorption profile were obtained as fingerprint in X-ray diffraction diagrams of the pertinent medicinal materials. We have discovered the similarities of 3 radix Rubiae samples gathered from different localities and their differences with Rubia tinctorum, the similarities and differences between 7 species belonging to Fritillaria Genus, the similarities of 2 rhizoma Dioscoreae samples from different localities and their differences with 2 counterfeits. The result points to a promising prospect in achieving an objective assessment of genuineness at TCM drugs.

Drugs, Chinese Herbal↗
PubMed1997

[Crystal and molecular structure of the antimalarial agent alpha-(dibutylaminomethyl)-2, 7-dichloro-9-(p-chlorobenzylidene)-4- fluorenemethanol(benflumetol)].

The three-dimensional crystal and molecular structure of benflumetol(I), alpha-(dibutylaminomethyl)-2, 7-dichloro-9-(p-chlorobenzylidene)-4-fluorenemethanol, was determined by X-ray crystallography and compared with the crystal structures of the cinchona alkaloids. The aromatic rings of fluorene-phenyl system of benflumetol are twisted from each other by 52.8 degrees. The torsion angle of N-C-C-O of benflumetol is 47.6 degrees. The intramolecular aliphatic N-O distance in benflumetol is 2.709A, which is close to the N-O distance found in antimalarial cinchona alkaloids. Benflumetol contains an intramolecular hydrogen bond between the aliphatic nitrogen and oxygen atoms, no intermolecular hydrogen bond was found, which is different from the known amino alcohol antimalarials.

Antimalarials↗
PubMed1997

[The structure correction of villosolside].

The crystal structure of villosolside was determined by X-ray diffraction, which led to some stereochemical amendment of the structure proposed in the article by Xu CJ et al. in Acta Pharm Sin 1985, 20:652.

Crystallography, X-Ray↗
PubMed1993

[The crystal structure atlas data base system for chemical constituents of Chinese traditional and folk medicine].

The atlas data base system for chemical constituents of Chinese traditional and folk medicine is the first one for single crystal structure in China. It includes about 250 crystal structures of chemical ingredients of Chinese traditional and folk medicine. It has searching, plotting and computing functions. It is a useful reference base. All softwares are written in dbaseIII, FORTRAN and Assembler Languages. They can be run on PC-286,386,486 and their compatible microcomputers.

Crystallography↗
PubMed1993

[Studies on diterpenoids from leaves of Tripterygium wilfordii].

Tripterygium wilfordii Hook f. has been used as a medicinal herb in traditional Chinese medicine and as an insecticide by the Chinese for hundreds of years. Recently, this plant has been used to treat cancer, rheumatic arthritis and various skin diseases in some Chinese clinics. It is of interest to note that Tripterygium also showed significant antifertility activities. The active principles of the anti-inflammatory, immunosuppressive and antifertile actions in Tripterygium are diterpenoid containing triepoxides, but information on its chemistry is limited to the woody part of the root and the root bark. Recently, we have studies the leaves of Tripterygium (collected at Zhejiang province, China), and isolated two novel diterpenoids by chromatography named tripdioltonide (8) and 13,14-epoxide 9,11,12-trihydroxytriptolide (9), besides triptonide (1), triptolide (2), tripdiolide (3), triptolidenol (4), 16-hydroxyl-triptolide (5), tripchlorolide (6) and triptriolide (7). Their structures were established by chemical reactions, TLC, UV, MS, IR, 1H-1H COSY, 1H-13C COSY, DEPT spectrometric investigation. The structure of tripdioltonide was further confirmed by X-ray analysis.

Diterpenes↗
PubMed1993

[Studies on the chemical constituents of Ventilago leiocarpa Benth].

Three anthraquinones (1-3) and two naphthoquinones(4,5) were isolated from the root of Ventilago leiocarpa Benth (Rhamnaceae). On the basis of spectroscopic data and X-ray diffraction analysis compound 5, ventilagolin, was shown to be a new naphthoquinone occurring as a racemate.

Drugs, Chinese Herbal↗
PubMed1993

[The structure identification of zhepiresionol].

A new 3,7-dioxabicyclo[3, 3, O] octan-6-one named zhepeiresinol was isolated from Fritillaria thumbergii Miq. The spectroscopic and X-ray diffraction analysis established the structure as 2-(3',5'-dimethoxy-4'-hjydroxyphenyl)-3,7-dioxabicyclo[3, 3, O]octan-6-one.

Bridged Bicyclo Compounds↗
PubMed1992

Studies on the Constituents of Adelostemma gracillimum.

The glycone portion of the glycoside of ADELOSTEMMA GRACILLIMUM Hook. f. (Asclepiadaceae) was investigated. Three known polyoxypregnane ester-type aglycones, penupogenin ( 1) (1, 2), kidjoranine ( 2) (1, 3), and gagamine ( 3) (4, 5), and one new compound named gracigenin ( 4) were isolated and their structures were characterized on the basis of spectroscopic evidence, and that of ( 4) was determined by X-ray crystallography. It was found to possess an unprecedented 8,14- SECO-polyoxypregnane ester-type skeleton, and 4 is the first compound with this C (21)-steroid type skeleton to be found in nature.

Journal Article↗