Qinghu Wang

Two new flavonoid glycosides from Artemisia frigida Willd.

An investigation of the n-BuOH-soluble fraction from the aerial parts of Artemisia frigida has led to the isolation of two new flavonoid glycosides, named friginoside A and friginoside B. Their structures were characterized as 5,7-dihydroxy-3′,4′,5′-trimethoxy flavone 7-O-β-d-glucuronide (1) and 5,7-dihydroxy-3′,4′,5′-trimethoxyflavone 7-O-β-d-glucuronyl-(1 → 2)O-β-d-glucuronide (2) on the basis of 1D and 2D NMR spectral analysis.

Lignans from Syringa pinnatifolia Hemsl. Var. alashanensis

Two new lignans, syripinnalignans A and B (1 and 2), together with two known lignans, were isolated from the stem of Syringa pinnatifolia Hemsl. Var. alashanensis. The structures of 1 and 2 were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques.

A new 6,9′-cyclolignan from Syringa pinnatifolia

A new lignan, 4,4′-dihydroxy-3,3′-dimethoxy-6,9′-cycloligna-7,8′-dien-9′-al, was isolated from the stem of Syringa pinnatifolia Hems1. var. alashanensis MA. et S.Q. Zhou (S. pinnatifolia). This is the first report on the structure elucidation of a new compound based on spectroscopic methods including UV, IR, ESI-MS, 1D NMR and 2D NMR techniques.

A biflavonoid glycoside from Lomatogonium carinthiacum (Wulf) Reichb

A biflavonoid glycoside with a new carbon skeleton, named carinoside A, was isolated from the n-BuOH crude extract of the whole plant of Lomatogonium carinthiacum (Wulf) Reichb. The structure of the new compound was elucidated by using spectroscopic methods, including UV, IR, HR-ESI-MS and extensive 1D and 2D NMR techniques.

The structural elucidation and antimicrobial activities of two new monoterpene glucoside derivatives from Lomatogonium carinthiacum (Wulf) Reichb.

Lomatogonium carinthiacum (Wulf) Reichb (L. carinthiacum), Habirigendigeda in Mongolian, a species of the genus Lomatogonium, is distributed throughout Inner Mongolia, Shanxi, Xinjiang of China, and is used as a remedy for plague, influenza, typhoid, liver disease, and jaundice in Mongolian medicine. Terpenoids and flavonoids have been reported from L. carinthiacum. The terpenoidsterpenoids exhibited significant pharmacological activities including anti-inflammatory and cytotoxicity against A 549 lung carcinoma, WI-38 lung fibroblast, VA-13 lung malignant tumor, and HepG2 human liver tumor cells, which are consistently used in Mongolian clinics. In the course of a search for antimicrobial active compounds, the ethanol extract of the whole plant of L. carinthiacum was investigated. The current paper describes the isolation and structure elucidation of two monoterpene glucoside derivatives, and their antimicrobial activities are reported.

Two new sesquiterpene lactone glycosides from Artemisia frigida Willd.

The investigation of EtOAc-soluble fraction from the aerial parts of Artemisia frigida has led to the isolation of two new sesquiterpene lactone glycosides, named as artemofriginoside A and artemofriginoside B. Their structures were characterized as 3β-(β-d-glucopyranosyloxy)-8β-(p-hydroxyphenylacetyloxy)-4(15),10(14),11(13)-guaiatrien-1α,5β,6β,7αH-12,6-olide (1) and β-(β-d-glucopyranosyloxy)-8β-(2-hydroxy-3-methylbutanoyloxy)-4(15),10(14),11(13)-guaiatrien-1α,5β,6β,7αH-12,6-olide (2), on the basis of 1D and 2D NMR spectral analysis.

The Structure Elucidation and Antimicrobial Activities of Nonsterol Triterpenoids from Ixeris chinensis

Abstract An investigation of the petroleum ether extract from Ixeris chinensis Nakai has led to the isolation of a new compound, 3-O-acetyl-22,28-cyclobauer-7-en-3β-ol (1), together with four known compounds which have been isolated from this plant for the first time, namely taraxast-20-en-3β-ol (2), 3-O-acetyl-taraxast-20-en-3β-ol (3), taraxast-20(30)-en-3β-ol (4), and 3-O-acetyl-taraxast-20(30)- en-3β-ol (5). The structures of the isolated compounds have been elucidated on the basis of spectroscopic methods including UV, IR, ESI-MS, 1D NMR, 2D NMR techniques, and by comparison with data reported in the literature. All compounds have been evaluated for their activity against various bacteria and shown to give good results

A new sesquiterpene from Ixeris chinensis

The petroleum ether (PE) extract from Ixeris chinensis was submitted to chromatographic separation. A new sesquiterpene, namely 14-noreudesma-3-hydroxy-3-en-2,9-dione, was isolated from the PE extract. The structures of the sesquiterpene was elucidated by using spectroscopic methods, including UV, IR, HR-ESI-MS and extensive 1D and 2D NMR techniques.

Structure elucidation and NMR assignments of an alkaloid from Ixeris chinensis Nakai

Abstract A new alkaloid, 2-amino-1,6-dihydro-pyridine-5-carbaldehyde (1), together with four known compounds, namely 4-hydroxybenzaldehyde (2), 4-hydroxyacetophenone (3), acetophenone-4-O-β-d-glucoside (4), 2-hydroxyl-6-methoxyacetophenone-4-O-β-d-glucoside (5), were isolated from the CHCl3 extract from Ixeris chinensis Nakai. The structures of 1 was elucidated by spectroscopic methods, including UV, IR, HR-ESI-MS and extensive 1D and 2D NMR techniques.

Structure elucidation and NMR assignments of a new 6,9-cyclotetrahydrofuranlignan from Syringa pinnatifolia

A new 6,9-cyclotetrahydrofuranlignan, 3,3′-dimethoxy-4,4′-dihydroxy-8β,9β,8′α-6,9-cyclotetrahydrofuranlignan, was isolated from the stem of Syringa pinnatifolia Hems1.var. alashanensis MA. et S. Q. ZHOU. Its structures were elucidated on the basis of spectroscopic methods including UV, IR, ESI-MS, 1D NMR and 2D NMR.