From Senecio tsoongianus, two pairs of enantiomeric isomers, tsoongianolides A (1) and B (2), tsoongianolides C (3) and D (4) were isolated. Their structures were elucidated by 1D and 2D-NMR techniques and X-ray diffr...From Senecio tsoongianus, two pairs of enantiomeric isomers, tsoongianolides A (1) and B (2), tsoongianolides C (3) and D (4) were isolated. Their structures were elucidated by 1D and 2D-NMR techniques and X-ray diffractions. The cytotoxicity to KB cell of 1 and 2 is also reported.展开更多
Two new eremophilanolides, tsoongianolide E and F, were isolated from Senecio tsoongianus. Their structures were elucidated on the basis of NMR and MS spectra. Both of these two compounds showed in vitro cytotoxicity ...Two new eremophilanolides, tsoongianolide E and F, were isolated from Senecio tsoongianus. Their structures were elucidated on the basis of NMR and MS spectra. Both of these two compounds showed in vitro cytotoxicity to cultured KB and A-549 cancer cell lines.展开更多
Two series of territrem B analogues (6, 11) were designed and synthesized from jujubogenin 2. Compound 11c inhibited AChE with the ratio of 70% at 10-4 mol/L. Compounds 5a, 5b, 6a and 11b showed moderate cytotoxicit...Two series of territrem B analogues (6, 11) were designed and synthesized from jujubogenin 2. Compound 11c inhibited AChE with the ratio of 70% at 10-4 mol/L. Compounds 5a, 5b, 6a and 11b showed moderate cytotoxicity on cultured KB cells at 10-6 mol/L. Compounds 5c and 6b alleviated injury arising from oxygen-glucose deprivation (OGD).展开更多
A new taxoid, 2-deacetyl-2a, 14b-dihydroxybaccatin IV (1), was isolated from the leaves and branches of Taxus chinensis together with the known compound baccatin IV (2). The structure of the new compound was elucidat...A new taxoid, 2-deacetyl-2a, 14b-dihydroxybaccatin IV (1), was isolated from the leaves and branches of Taxus chinensis together with the known compound baccatin IV (2). The structure of the new compound was elucidated by spectroscopic techniques. The detailed 13C NMR assignments of baccatin IV are reported for the first time.展开更多
A series of Reed Pulps were prepared in which the level of Non-Process Elements(NPEs), including calcium, manganese,copper,iron were seclectively enriched and depleted, these pulps were then oxygen delignification,and...A series of Reed Pulps were prepared in which the level of Non-Process Elements(NPEs), including calcium, manganese,copper,iron were seclectively enriched and depleted, these pulps were then oxygen delignification,and the pulps were characterized according to kappa number,viscosity,brightness. The results indicated that the enrichment of NPEs have an important effulence on delignification,pulp viscosity and brightness, iron is the most harmful during oxygen delignification but manganese is just like a kind of aid and can enhance brightness and delignification.展开更多
Two series of territrem B analogues (10a-10c and 18) have been designed and synthesized from jujubogenin 5a which was prepared from jujubogenin glycosides 5b obtained from the leaves of Zizyphus jujuba. The structur...Two series of territrem B analogues (10a-10c and 18) have been designed and synthesized from jujubogenin 5a which was prepared from jujubogenin glycosides 5b obtained from the leaves of Zizyphus jujuba. The structures of the new compounds were confirmed by H-, 1 13C-NMR and MS data. Compounds 10c and 18 showed weak inhibitory effect on AChE at 10-4 mol/L.展开更多
基金This work is financially supported in part by the Life Sciences Special Fund of Chinese Academy of Sciences Supported by the Ministry of Finance (STZ-00-24) the Yunnan Province Foundation of Applied Basic Research (2000C0072M) the Chine-France PRA (g
文摘From Senecio tsoongianus, two pairs of enantiomeric isomers, tsoongianolides A (1) and B (2), tsoongianolides C (3) and D (4) were isolated. Their structures were elucidated by 1D and 2D-NMR techniques and X-ray diffractions. The cytotoxicity to KB cell of 1 and 2 is also reported.
文摘Two new eremophilanolides, tsoongianolide E and F, were isolated from Senecio tsoongianus. Their structures were elucidated on the basis of NMR and MS spectra. Both of these two compounds showed in vitro cytotoxicity to cultured KB and A-549 cancer cell lines.
文摘Two series of territrem B analogues (6, 11) were designed and synthesized from jujubogenin 2. Compound 11c inhibited AChE with the ratio of 70% at 10-4 mol/L. Compounds 5a, 5b, 6a and 11b showed moderate cytotoxicity on cultured KB cells at 10-6 mol/L. Compounds 5c and 6b alleviated injury arising from oxygen-glucose deprivation (OGD).
文摘A new taxoid, 2-deacetyl-2a, 14b-dihydroxybaccatin IV (1), was isolated from the leaves and branches of Taxus chinensis together with the known compound baccatin IV (2). The structure of the new compound was elucidated by spectroscopic techniques. The detailed 13C NMR assignments of baccatin IV are reported for the first time.
文摘A series of Reed Pulps were prepared in which the level of Non-Process Elements(NPEs), including calcium, manganese,copper,iron were seclectively enriched and depleted, these pulps were then oxygen delignification,and the pulps were characterized according to kappa number,viscosity,brightness. The results indicated that the enrichment of NPEs have an important effulence on delignification,pulp viscosity and brightness, iron is the most harmful during oxygen delignification but manganese is just like a kind of aid and can enhance brightness and delignification.
文摘Two series of territrem B analogues (10a-10c and 18) have been designed and synthesized from jujubogenin 5a which was prepared from jujubogenin glycosides 5b obtained from the leaves of Zizyphus jujuba. The structures of the new compounds were confirmed by H-, 1 13C-NMR and MS data. Compounds 10c and 18 showed weak inhibitory effect on AChE at 10-4 mol/L.
