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Three new pentacyclic triterpenes, trivially named sandkoetjapic acids A-C (1-3), have been isolated from the leaves extract of Sandoricum koetjape, along with the known triterpenes 3-oxo-olean-12-en-29-oic (4), bryonolic (5), and bryononic (6) acids. The structures of the new triterpenes were determined mainly by NMR spectroscopic and mass spectroscopic data. The isolation of these pentacyclic triterpenes in the plant's leaves is for the first time. Preliminary biological evaluation of 1-6 was done against eight receptor tyrosine kinases (RTKs), including EGFR, HER2, HER4 (epidermal growth factor receptor), IGF1R, InsR (insulin receptor), KDR (kinase insert domain receptor), and PDGFRα/-β (platelet-derived growth factor receptor), and their inhibitory properties against β-lactamase. The results showed that none of them were active both as the inhibitors of these RTKs and β-lactamase.

Two new quinone derivatives, epoxyquinophomopsins A (1) and B (2), were purified from the EtOAc extract of endophytic fungus Phomopsis sp isolated from Morus cathayana. The structures of both compounds were determined based on 1D and 2D NMR and mass spectral data, as well as by x-ray diffraction analysis for 1. Compounds 1 and 2 were screened against eight receptor- (RTKs) and eight non-receptor tyrosine kinases (nRTKs). Both compounds showed strong inhibitory properties against Bruton's Tyrosine Kinase (nRTK) with their kinase activity were 19% and 20%, respectively. Only compound 1 that showed strong inhibitory properties against RTKs EGFR and HER-4 with its kinase activity were 16 and 15%, respectively. Thus, both compounds have potential as tyrosine kinase inhibitors.

Three new 5,6-dihydro-α-pyrones derivatives, named (S)-rugulactone (1) pulchrinervialactone A (2), and pulchrinervialactone B (4), along with one known pyrone, cryptobrachytone C (3), and three known amide derivatives (5-7) have been isolated from the leaves of Cryptocarya pulchrinervia. The structures of 1-7 were elucidated based on extensive spectroscopic data and comparison with literatures. The configurations of compounds 3 and 4 were established by single crystal X-ray diffraction analysis. This is also the first report in finding (S)-rugulactone (1) as a natural product. In addition, the preliminary cytotoxic activity of the isolated compounds was evaluated against P-388 cells using the [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. All the pyrones, except compound 4, were active significantly inhibiting the growth of P-388 cells, while the amides derivatives (5-7) showed moderate to weak activities. Therefore, compounds 1-3 could be potentially examined further for anticancer agents.

Two new quinone derivatives, epoxyquinophomopsins A (1) and B (2), were purified from the EtOAc extract of endophytic fungus Phomopsis sp isolated from Morus cathayana. The structures of both compounds were determined based on 1D and 2D NMR and mass spectral data, as well as by x-ray diffraction analysis for 1. Compounds 1 and 2 were screened against eight receptor- (RTKs) and eight non-receptor tyrosine kinases (nRTKs). Both compounds showed strong inhibitory properties against Bruton's Tyrosine Kinase (nRTK) with their kinase activity were 19% and 20%, respectively. Only compound 1 that showed strong inhibitory properties against RTKs EGFR and HER-4 with its kinase activity were 16 and 15%, respectively. Thus, both compounds have potential as tyrosine kinase inhibitors.

Three andirobin- and one trijugin-class limonoids, named koetjapins A-D (1–4), have been isolated from the seed extracts of Sandoricum koetjape. The structures of these compounds were determined by extensive NMR and mass spectral data, and the chemotaxonomic significance of these limonoids in the family Meliaceae is highlighted. Preliminary biological activity showed that only compound 4 has significant inhibitory activity against P-388 cells, while antibacterial tests showed that none of these compounds were active.

Two new prenylated flavones, artoindonesianins A-2 (1) and A-3 (2), together with three known prenylated flavones, artonin B (3), heterophyllin (4) and cudraflavone C (5), have been isolated and identified from the chloroform extract of the heartwood of Artocarpus champeden. The structures of these compounds were determined on the basis of spectroscopic data, including UV, IR, 1-D and 2-D NMR, and mass spectra. The cytotoxic properties of the new compounds, together with three prenylated flavones isolated previously, artoindonesianins Q (6), R (7) and T (8), were evaluated against murine leukemia P-388 cells. Based on their IC50 values, compounds 1, 2, 4, 5 and 8 showed strong cytotoxic properties.

Eleven known prenyl xanthones, isolated from the pericarp of Garcinia mangostana, were tested for their ability to inhibit the phosphorylation of kinase domain receptor (KDR) tyrosine kinase. α-Mangostin was found to inhibit phosphorylation of KDR. α-Mangostin also showed to inhibit phosphorylation of the Y1175 residue of KDR (10 μM). This is the first report that α-mangostin inhibited the phosphorylation of KDR tyrosine kinase and also the Y1175 residue of KDR. α-Mangostin also showed inhibitory effects on proliferation of human umbilical vein endothelial cells (HUVECs) (IC(50) 1.2 μM) and human umbilical artery endothelial cells (IC(50) 2.4 μM), as well as the migration (IC(50) 0.034 μM) and tubule formation (at the concentrations of 0.6 and 1.2 μM) of HUVECs. These results suggest that the inhibition of the phosphorylation of KDR tyrosine kinase is concerned in the anti-angiogenic activity of α-mangostin.

A new oligostilbenoid derivative, diptoindonesin F (1), along with five known oligostilbenoids, (-)-ampelopsin A (2), (-)-alpha-viniferin (3), ampelopsin E (4), (-)-vaticanol B (5), and (-)-hemsleyanol D (6), were isolated from the methanol extract of the tree bark of Shorea gibbosa. The structure of the new compound was determined based on the analysis of spectroscopic data, including UV, IR, NMR 1-D and 2-D, and mass spectra. Cytotoxic properties of the isolated oligostilbenoids were evaluated against murine leukemia P-388 cells with the result that compounds 2 and 4 showed the highest cytotoxicity.