Some natural products, such as traditional Chinese medicines（TCMs）, contain compounds with anticancer activity and have attracted a great interest in recent years as alternative anticancer therapies. A quick and con...Some natural products, such as traditional Chinese medicines（TCMs）, contain compounds with anticancer activity and have attracted a great interest in recent years as alternative anticancer therapies. A quick and convenient assay for screening antimicrotubule compounds in which in vitro microdialysis/high-performance liquid chromatography （HPLC） is used to monitor the binding of the compounds extracted from TCM Taxus cuspidata Siebold ＆ Zucc（Taxus） to microtubules is reported. It was observed that the extract of Taxus contains at least five compounds which have affinity interaction with microtubules by biological fingerprinting analysis, and they were identified as the taxoids of taxol, baccatin III, 10-deacetylbaccatin Ⅲ（10-DAB）, cephalomannine and 7-epi-10-deacetyltaxol （7-epi-10-DAT） based on the comparison of their high-performance liquid chromatographic/mass spectrometric and UV spectra with those of the standard samples, both assembly-promoting and disassembly-inhibiting characteristics of those compounds were evaluated. It was observed that baccatin Ⅲ and 10-DAB bound to microtubules and the binding degrees were influenced by GTP. Competitive binding behavior of taxol with other four taxoids to microtubules was also investigated.展开更多
New D-seco-taxoids were synthesized from 1-deoxybaccatinⅥand their structures were confirmed by 1H NMR,13C NMR, ESIMS and X-ray crystallography.The key step of the synthesis involved the opening of the oxetane ring u...New D-seco-taxoids were synthesized from 1-deoxybaccatinⅥand their structures were confirmed by 1H NMR,13C NMR, ESIMS and X-ray crystallography.The key step of the synthesis involved the opening of the oxetane ring under acid and basic conditions in order to obtain new multidrug resistance（MDR） reversal agents and new synthetic precursors of paclitaxel analogues.展开更多
Microbial trdrisformation of taxoids was inveStigared: taxoid 2 was transformed into 1β and 14β hydroxylated derivahves 3 and 4, unnatural taxoid 6 was transformed into 1β-hydroxy derivative 7 and 11(15-1) abeotaxa...Microbial trdrisformation of taxoids was inveStigared: taxoid 2 was transformed into 1β and 14β hydroxylated derivahves 3 and 4, unnatural taxoid 6 was transformed into 1β-hydroxy derivative 7 and 11(15-1) abeotaxane 8. Taxoids with an oxetane ring, 11-13 were synthesized from 1 via chemical reachons.展开更多
Three novel bicyclic taxane diterpenoids with the rare 6/12-membered rings wereisolated from the need ies of Taxus chinensis var. mairei. The structures were established with the help of 1D and 2D NMR spectral analysis.
A new taxane diterpenoid, named 7-deacetoxy taxinine J, together with ten knowncompounds were isolated from the needles of Taxus × media Hickiii. The structures of allcompounds were elucidated and identified by s...A new taxane diterpenoid, named 7-deacetoxy taxinine J, together with ten knowncompounds were isolated from the needles of Taxus × media Hickiii. The structures of allcompounds were elucidated and identified by spectroscopic methods. T'he structure of 7-deacetoxytaxinine J was further confirmed by X-ray crystallographic analysis. The structure of the knowncompound, taxinine E, was also revised.展开更多
-An oxetane ring can be constructed from 5 α-acyloxy-Δ4(20) -taxoids with osmylation as the first step in the usual manner. The innovation reported here is the use of an intramolecularly available acyl group for the...-An oxetane ring can be constructed from 5 α-acyloxy-Δ4(20) -taxoids with osmylation as the first step in the usual manner. The innovation reported here is the use of an intramolecularly available acyl group for the protection of 20-OH by an unexpected 5-to 20-migration under slightly basic conditions.展开更多
Two sets of CCD photometric observations for contact binary TU Boo were obtained in 2020 and 2021.Different from its asymmetric light curves published from the literature,our BVRcIc-band curves show that the heights o...Two sets of CCD photometric observations for contact binary TU Boo were obtained in 2020 and 2021.Different from its asymmetric light curves published from the literature,our BVRcIc-band curves show that the heights of maximum are almost equal.These distortions of light curves possibly indicate that the components were active in past 25 yr,but they were stable in the last two years.For total-eclipse binary TU Boo,due to some star-spots on the surface of the components,the physical structure obtained by many investigators are different.Therefore,the symmetric multi-color light curves in 2020,2021 are important for understanding configuration and evolution of this system.By using the Wilson–Devinney program,it is confirmed that TU Boo is an A-type shallow-contact binary with the temperature difference ofΔT=152 K and fill-out of f=14.67%.In the O−C diagram of orbital period analysis,a cyclic oscillation superimposed on a continuous decrease was determined.The long-term decreasing is often explained by the mass transfer from the more massive star to less massive one,this system will evolve into a deeper contact binary with time.The cyclic oscillations computed from much more CCD times of light minimum maybe result from the light-travel time effect via the presence of a third body.These characters of structure,evolution and ternary belong to typical A-type W UMa binaries with spectral G.展开更多
基金the National Natural Science Foundation of China(No.90709021)Knowledge Innovation Program of Chi-nese Academy of Sciences(No.KJCX2.YW.HO9)
文摘Some natural products, such as traditional Chinese medicines（TCMs）, contain compounds with anticancer activity and have attracted a great interest in recent years as alternative anticancer therapies. A quick and convenient assay for screening antimicrotubule compounds in which in vitro microdialysis/high-performance liquid chromatography （HPLC） is used to monitor the binding of the compounds extracted from TCM Taxus cuspidata Siebold ＆ Zucc（Taxus） to microtubules is reported. It was observed that the extract of Taxus contains at least five compounds which have affinity interaction with microtubules by biological fingerprinting analysis, and they were identified as the taxoids of taxol, baccatin III, 10-deacetylbaccatin Ⅲ（10-DAB）, cephalomannine and 7-epi-10-deacetyltaxol （7-epi-10-DAT） based on the comparison of their high-performance liquid chromatographic/mass spectrometric and UV spectra with those of the standard samples, both assembly-promoting and disassembly-inhibiting characteristics of those compounds were evaluated. It was observed that baccatin Ⅲ and 10-DAB bound to microtubules and the binding degrees were influenced by GTP. Competitive binding behavior of taxol with other four taxoids to microtubules was also investigated.
基金the National Natural Science Foundation of China(No.30672506)Leading Academic Discipline Project of Shanghai Municipal Education Commission(No.J50102)
文摘New D-seco-taxoids were synthesized from 1-deoxybaccatinⅥand their structures were confirmed by 1H NMR,13C NMR, ESIMS and X-ray crystallography.The key step of the synthesis involved the opening of the oxetane ring under acid and basic conditions in order to obtain new multidrug resistance（MDR） reversal agents and new synthetic precursors of paclitaxel analogues.
文摘Microbial trdrisformation of taxoids was inveStigared: taxoid 2 was transformed into 1β and 14β hydroxylated derivahves 3 and 4, unnatural taxoid 6 was transformed into 1β-hydroxy derivative 7 and 11(15-1) abeotaxane 8. Taxoids with an oxetane ring, 11-13 were synthesized from 1 via chemical reachons.
文摘Three novel bicyclic taxane diterpenoids with the rare 6/12-membered rings wereisolated from the need ies of Taxus chinensis var. mairei. The structures were established with the help of 1D and 2D NMR spectral analysis.
文摘A new taxane diterpenoid, named 7-deacetoxy taxinine J, together with ten knowncompounds were isolated from the needles of Taxus × media Hickiii. The structures of allcompounds were elucidated and identified by spectroscopic methods. T'he structure of 7-deacetoxytaxinine J was further confirmed by X-ray crystallographic analysis. The structure of the knowncompound, taxinine E, was also revised.
文摘-An oxetane ring can be constructed from 5 α-acyloxy-Δ4(20) -taxoids with osmylation as the first step in the usual manner. The innovation reported here is the use of an intramolecularly available acyl group for the protection of 20-OH by an unexpected 5-to 20-migration under slightly basic conditions.
基金sponsored by Natural Science Foundation of Xinjiang Uygur Autonomous Region (No.2022DO1A164)the Joint Research Found (No.U1831109)in Astronomy under cooperative agreement between the National Natural Science Foundation of China (NSFC)and Chinese Academy of Sciences (CAS)the Natural Science Foundation of Shandong Province (No.ZR2020QA048)。
文摘Two sets of CCD photometric observations for contact binary TU Boo were obtained in 2020 and 2021.Different from its asymmetric light curves published from the literature,our BVRcIc-band curves show that the heights of maximum are almost equal.These distortions of light curves possibly indicate that the components were active in past 25 yr,but they were stable in the last two years.For total-eclipse binary TU Boo,due to some star-spots on the surface of the components,the physical structure obtained by many investigators are different.Therefore,the symmetric multi-color light curves in 2020,2021 are important for understanding configuration and evolution of this system.By using the Wilson–Devinney program,it is confirmed that TU Boo is an A-type shallow-contact binary with the temperature difference ofΔT=152 K and fill-out of f=14.67%.In the O−C diagram of orbital period analysis,a cyclic oscillation superimposed on a continuous decrease was determined.The long-term decreasing is often explained by the mass transfer from the more massive star to less massive one,this system will evolve into a deeper contact binary with time.The cyclic oscillations computed from much more CCD times of light minimum maybe result from the light-travel time effect via the presence of a third body.These characters of structure,evolution and ternary belong to typical A-type W UMa binaries with spectral G.
