Minor Humulane and Eremophilane Sesquiterpenoids from Syringa pinnatifolia and Their Protective Effect Against Oxidative Injuries in H9c2 Cells.

As a part of systematic research, an ongoing phytochemical investigation of the sesquiterpenoid-containing fraction led to the isolation of five new sesquiterpenoids from the peeled stems of Syringa pinnatifolia, including two pairs of enantiomeric humulane-type (±)-alashanoids A1 and B1 (1 and 2) and one eremophilane-type alashanoid C1 (3). These structures were elucidated by the analysis of extensive spectroscopic data, including ESI-MS and 1D and 2D NMR, and the absolute configuration was determined by comparing its experimental and calculated electronic circular dichroism and calculated NMR. These isolates exhibited moderate in vitro cardioprotective effects against oxidative injuries in H9c2 cells.

Alashanoids O-S, seco-Humulane and Eremophilane Sesquiterpenoids from Syringa pinnatifolia.

Five new sesquiterpenoids, alashanoids O-S (1-5), along with three known analogs (6-8) were isolated from the peeled stems of Syringa pinnatifolia. Their structures were elucidated by analysis of extensive spectroscopic data including ESI-MS, 1D, 2D NMR. The absolute configurations were determined by comparing its experimental and calculated electronic circular dichroism, calculated OR, calculated NMR, and single crystal X-ray diffraction data analysis. Compounds 1 and 2 belong to the seco-humulane type and possess a rare 13-membered oxygen heterocycle framework, and 3-5 belong to eremophilane-type. Compounds 1, 2, and 5 showed inhibitory effects against NO production in LPS-induced RAW264.7 macrophage cells with its IC50 values of 11.86±2.34, 72.08±7.72, and 69.22±15.29 µM, respectively, compared with the positive control indomethacin (IC50 =31.52 µM).

Humulane-type and germacrane-type sesquiterpenoids from the fruits of Xanthium spinosum Linn.

Eight undescribed humulane-type sesquiterpenoids (xanthspinol A-E, I, J and N), three undescribed germacrane-type sesquiterpenoids (xanthspinol F, G and O) and twelve known compounds were isolated from the fruits of Xanthium spinosum. The structures of the undescribed compounds were elucidated by analyses of spectroscopic data, electronic circular dichroism (ECD) calculations, dimolybdenum tetraacetate [Mo2(OAc)4]-induced circular dichroism (ICD) spectra, a CD exciton chirality method and the modified Mosher's method. Xanthspinol A and B featured a humulane skeleton containing a 2,5-dihydrofuran fragment. Putative biosynthetic pathways for the undescribed compounds are proposed. Xanthspinol N, 8-epi-isoxanthanol and deacetyl-4-epixanthanol showed moderate activity against Coxsackie virus B3 (CVB3) with IC50 values of 8.70, 3.70 and 3.70 µM, respectively.

Humulane-Type Macrocyclic Sesquiterpenoids From the Endophytic Fungus Penicillium sp. of Carica papaya.

Three new humulane-type sesquiterpenoids, penirolide A (1), penirolide B (2), and 10-acetyl-phomanoxide (3), together with three known compounds aurasperone A (4), pughiinin A (5), and cyclo(l-Leu-l-Phe) (6) were isolated from the endophytic fungus Penicillium sp. derived from the leaves of Carica papaya L. Their structures including their absolute configurations were determined based on the analysis of NMR and HRESIMS spectra, NMR chemical shifts, and ECD calculations. Compounds 2, 3, 5, and 6 significantly inhibited glucagon-induced hepatic glucose production, with EC50 values of 33.3, 36.1, 18.8, and 32.1 µM, respectively. Further study revealed that compounds 2, 3, 5, and 6 inhibited hepatic glucose production by suppression of glucagon-induced cAMP accumulation.

[Advances on anti-tumor mechanisms of zerumbone].

Zerumbone(ZER), one of humulane-type sesquiterpenoids, showed its unique advantage against tumor activities. The main underlying mechanisms include inhibiting the growth and proliferation of cancer cells, inducing apoptosis of cancer cells and differentiation of cancer cells, regulating immune function, inhibiting invasion and metastasis of cancer cells, and reversing multidrug resistance of cancer cells. Studies on ZER focusing its cytotoxic or anti-tumor is one of hot topic. Currently, with the increasing studies on ZER, the clarified mechanisms are getting rich. The present paper describes a summary of its anti-tumor mechanism of action and helps to provide significant reference to more in-depth research.

Leptogorgins A-C, Humulane Sesquiterpenoids from the Vietnamese Gorgonian Leptogorgia sp.

Leptogorgins A-C (1-3), new humulane sesquiterpenoids, and leptogorgoid A (4), a new dihydroxyketosteroid, were isolated from the gorgonian Leptogorgia sp. collected from the South China Sea. The structures were established using MS and NMR data. The absolute configuration of 1 was confirmed by a modification of Mosher's method. Configurations of double bonds followed from NMR data, including NOE correlations. This is the first report of humulane-type sesquiterpenoids from marine invertebrates. Sesquiterpenoids leptogorgins A (1) and B (2) exhibited a moderate cytotoxicity and some selectivity against human drug-resistant prostate cancer cells 22Rv1.

A pair of humulane sesquiterpenoid enantiomers from Syringa pinnatifolia.

Two humulane-type sesquiterpenoids, namely (+)-alashanoid I (1a) and (-)-alashanoid I (1b), were isolated as a pair of enantiomers from the peeled stems of Syringa pinnatifolia. Their structures were elucidated by extensive spectroscopic data (1 D and 2 D NMR, UV, and IR), and the absolute configurations were resolved by X-ray diffraction and experimental and calculated ECD data analysis.

[Phytochemical and pharmacological progress on humulane-type sesquiterpenoids].

Humulane-type sesquiterpenoids, widely distributed in plants and microbes, include three types: α-humulene, ß-humulene, and γ-humulene. Up to now, 98 humulane-type sesquiterpenoids have been reported, which possessed anti-tumor, anti-inflammatory, antibacterial, and antiviral activities. Herein, this paper describes their chemical constituents and pharmacological activities, hoping to bring benefits for further research and lay a foundation for investigating the structure-activity relationships.

Three New Humulane Sesquiterpenes from Cultures of the Fungus Antrodiella albocinnamomea.

Three new humulane-type sesquiterpenes, antrodols A-C (1-3), were isolated from cultures of the fungus Antrodiella albocinnamomea. Their structures were elucidated on the basis of extensive spectroscopic analysis. Antrodols A-C (1-3) are first examples of humulane-type sesquiterpenes isolated from cultures of higher fungi, and antrodol A (1) was the first report of humulane-type sesquiterpene with a methyl rearranged at C-3. All compounds were evaluated in the enzyme inhibition assay against two protein-tyrosine phosphatases (PTPs): MEG2 and PTP1Bc.