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Phytochemical investigation of the exudates of Commiphora opobalsamumled to the isolation of three new sesquiterpenoids, 2α-methoxy-6-oxogermacra-1(10),7(11)-dien-8,12-olide (1), 5β-10α-hydroxy-2α-methoxy-6-oxoguaia-7(11),8-dien-8,12-olide (2), and furanocadina-1(10),6,8-triene-4-ol (3), together with six known compounds. Their structures were elucidated on the basis of spectroscopic methods. [ABSTRACT FROM AUTHOR]

The combination of IL-2 (interleukin-2) and GM-CSF (granulocyte/macrophage colony-stimulating factor) has been broadly studied in antitumour immune therapy, but its efficacy is uncertain. To better exert the activities of the two cytokines and study them in a mouse model, we have constructed a bifunctional protein, hIL-2–mGM-CSF (human IL-2–mouse GM-CSF), fused to a C-terminal tag of six histidine residues (His6). The fusion protein was expressed in Escherichia coli as IBs (inclusion bodies). After extracting and clarifying the IBs, four methods of protein purification and refolding were compared in order to optimize the preparation technique. Of these methods, the best result was obtained with a four-step process consisting of (1) purification with denaturing affinity chromatography, (2) followed by fully denaturing the protein with system conversion, (3) then refolding by isovolumetric ultrafiltration and (4) finally, purification by anion-exchange chromatography. The purity of the hIL-2–mGM-CSF was approx. 95%, yielding approx. 20 mg of protein/l of culture. The fusion protein retained the natural activities of IL-2 and GM-CSF, with specific activities of 8.7×106and 1.1×107i.u./mg respectively. Flow-cytometric analysis indicated that hIL-2–mGM-CSF could specifically bind to the corresponding receptor-positive cells. The present study provides important preliminary information for studying the antitumour activity of hIL-2–mGM-CSF in vivo, which will facilitate future clinical research into the use of hIL-2/hGM-CSF in immune therapy. [ABSTRACT FROM AUTHOR]

Three new triterpenoids, turrapubesols A–C (1–3), and one new sesquiterpenoid, 1α,4α-dihydroxyeudesman-11-ene (4), along with 12 known terpenoids were isolated from Turraea pubescens. The structures of the terpenoids were established on the basis of extensive spectroscopic analyses and by a chemical transformation. The previous assignment of the NMR data for guaidiol (5) was corrected. Some of the triterpenoids exhibited cytotoxicity against the P-388 cell line. [ABSTRACT FROM AUTHOR]

Seventeen Daphniphyllum alkaloids, including two new pentacyclic alkaloids, yuzuric acid (1) and daphnezomic acid (2), and 15 known ones, were isolated from the fruits of Daphniphyllum oldhamii. The structures and configuration of the two new alkaloids were determined on the basis of spectroscopic methods, especially 2D NMR techniques. [ABSTRACT FROM AUTHOR]

Three new alkaloids, N-hydroxypaxdaphnine B (1), 21-O-acetylpaxdaphnine B (2), and methyl 17-hydroxyhomodaphniphyllate (3), were isolated from the fresh fruits of Daphniphyllum macropodum, together with six known alkaloids. Their structures were established on the basis of extensive spectroscopic and mass-spectrometric analyses in combination with chemical transformations. [ABSTRACT FROM AUTHOR]

Two new lignan glycosides, lanicepsides A and B (1 and 2), along with the eight known compounds 3–6, epipinoresinol, syringin, ethyl caffeate, and 5,6,7-trihydroxy-4′-methoxyflavone, including sesquiterpene lactones, lignans, and a flavone, were isolated from the ethanol extract of Saussurea laniceps. Their structures were determined by spectroscopic methods especially 1D- and 2D-NMR techniques. [ABSTRACT FROM AUTHOR]

Three new natural products, the taraxastane-type triterpenoid 1, the azafluorene-based constituent 2-hydroxyonychine (2), and the diterpenoid nemoralisin (3) were isolated from the EtOH extract of Polyalthia nemoralis, along with five known compounds. The structures of the new compounds were established by in-depth spectroscopic and mass-spectrometric analyses, as well as by chemical transformation. [ABSTRACT FROM AUTHOR]