Thirteen α-methylene aromatic araminenone and four α-methylene aromatic aminoketones were prepared by modified Mannich reaction. On the basis of isotopic labeling, a plausible way of cleavage was proposed for the fo...Thirteen α-methylene aromatic araminenone and four α-methylene aromatic aminoketones were prepared by modified Mannich reaction. On the basis of isotopic labeling, a plausible way of cleavage was proposed for the formation of the M^＋- 17 fragment peak in the MS of the α-methylene aromatic araminenone and aminoketones. The characteristic chemical shift of the olefinic protons in ^1H NMR is also discussed.展开更多
Hydrogels of dimethylaminoethyl acrylate methyl chloride quaternary salt (Q9) have been synthesized with different monomer ratio by copolymerization of this poorly studied monomer either with acrylic acid or with 2-me...Hydrogels of dimethylaminoethyl acrylate methyl chloride quaternary salt (Q9) have been synthesized with different monomer ratio by copolymerization of this poorly studied monomer either with acrylic acid or with 2-methylene bu-tane-1,4-dioic acid. Hydrogel swelling was measured as a function of the composition of the hydrogel and of the crosslinking agent ratio. High values of swelling have been obtained at very high crosslinking values (【14 wt %) and the equilibrium swelling was reached at very low time (less than 15 minutes). The swelling isotherms consisted of a steep initial portion and then levelled off as asymptotically to the equilibrium swelling limit. The experimental data suggest clearly that the swelling process obeys second-order kinetics. According to this, the kinetics rate constant and the equilibrium water content were determined at different comonomer composition and crosslinker concentration. The calculated kinetic constants ranged from 0.48 to 3.76 ×10-2 min-1 for poly (acrylic acid-co-Q9) hydrogels and from 0.68 to 4.0 ×10-2 min-1 for poly (2-methylene butane-1,4-dioic acid-co-Q9) hydrogels depending on the hydrogels composition. The diffusion process was evaluated for each hydrogel showing a non-Fickian type diffusion. In all cases was observed a considerable increase in diffusion coefficient as Q9 content increases.展开更多
Two new sterol have been isolated from the South China Sea marine organism. Compound 1 was isolated from the sponge Polymastia sobustia and compound 2 was obtained from the soft coral Sinularia inexplicata. Their stru...Two new sterol have been isolated from the South China Sea marine organism. Compound 1 was isolated from the sponge Polymastia sobustia and compound 2 was obtained from the soft coral Sinularia inexplicata. Their structures were established as 3 beta-hydroxy-stigmast-5en-7-one and 24-methylene cholestan -3 beta, 6 beta, 9 alpha, 19-tetrol by variety of spectral analysis such as IR, EIMS, 1DNMR, H-1-H-1 COSY, HMQC, HMBC, NOESY.展开更多
A simple, efficient and low-cost methodology for the synthesis of α-aryl-α,β-unsaturated esters using paraformaldehyde as a source of carbon was developed. Factors that control reaction yields such as temperature, ...A simple, efficient and low-cost methodology for the synthesis of α-aryl-α,β-unsaturated esters using paraformaldehyde as a source of carbon was developed. Factors that control reaction yields such as temperature, concentration and reaction time were evaluated. A mechanism is proposed based on experimental structures of the intermediates.展开更多
Objective: To isolate bioactive compounds from the endophytic fungus Fusarium sporotrichioides isolated from Rauwolfia yunnanensis, and investigate their pharmacological activities.Methods: The chemical constituents w...Objective: To isolate bioactive compounds from the endophytic fungus Fusarium sporotrichioides isolated from Rauwolfia yunnanensis, and investigate their pharmacological activities.Methods: The chemical constituents were isolated and purified by combining with ODS column chromatography, silica gel column chromatography and by performing semipreparative HPLC. Their structures were established on the basis of 1D NMR(1H-NMR and13C-NMR) and 2D NMR(1H–1H COSY,HSQC, HMBC and NOESY), as well as HRESIMS and comparison with literature data. In addition, the absolute configuration of compound 1 was determined by calculated ECD data.Results: One previously undescribed tetracyclic triterpenoid derivative, named as integracide L(1), 12aacetoxy-4,4-dimethyl-24-methylene-5a-cholesta-8,14-diene-2a,3β,11β-triol(2), 12a-acetoxy-4,4-dime thyl-24-methylene-5a-cholesta-8-momoene-2a,3β,11β-triol(3), 12a-acetoxy-4,4-dimethyl-24-methy lene-5a-cholesta-8,14-diene-3β,11β-triol(4), and 12a-acetoxy-4,4-dimethyl-24-methylene-5acholesta-8-momoene-3β,11β-triol(5) were isolated from F. sporotrichioide. Moreover, compound 1 was rare tetracyclic triterpenoid with single methyl replacement at C-4 position.Conclusion: Compound 1 was a new tetracyclic triterpenoid isolated from the endophytic fungus F.sporotrichioides. In addition, compound 2 could inhibit the growth of three different human cancer cells significantly. Compounds 3 and 5 were found to possess better cytotoxic activities on Hep G-2 cells than the other compounds, with IC50values of(2.8 ± 0.1) and(6.3 ± 0.3) μmol/L respectively.展开更多
P2X_(1) receptors and adrenoceptors are mainly responsible for vasoconstriction in a variety of blood vessels.However,previous studies have shown that α,β-methylene adenosine 5'-triphosphate(α,β-MeATP),a stabl...P2X_(1) receptors and adrenoceptors are mainly responsible for vasoconstriction in a variety of blood vessels.However,previous studies have shown that α,β-methylene adenosine 5'-triphosphate(α,β-MeATP),a stable analogue of ATP,can induce both pressor and depressor responses in la boratory animals.In this study,the effects of increasing intravenous doses of α,β-MeATP and noradrenaline(NA)(0-30 nmol/kg)administered at 20 min intervals on systolic(SBP),diastolic(DBP)and mean(MBP)blood pressure in groups of anesthetized mice(n=6)were compared.Both α,β-MeATP and NA caused transient,dose-dependent increases in SBP,DBP and MBP but the effect of α,β-MeATP was more rapid and significantly larger at doses of 10 and 30 nmol/kg(P<0.01).At the dose of 30 nmol/kg,α,β-MeATP increased SBP,DBP and MBP by 65.8±7.0,65.7±5.0 and 65.7±5.5 mmHg,respectively,compared to increases of 36.8±4.6,33.3±4.9 and 34.5±4.7 mmHg,respectively,produced by NA.These results indicate P2X_(1) receptors play an important role in BP regulation although purinergic vasoconstriction alone may not explain the more potent pressor response to α,β-MeATP in the anesthetized mouse.展开更多
基金supported by the National Natural Science Foundation of China(No.39970867).
文摘Thirteen α-methylene aromatic araminenone and four α-methylene aromatic aminoketones were prepared by modified Mannich reaction. On the basis of isotopic labeling, a plausible way of cleavage was proposed for the formation of the M^＋- 17 fragment peak in the MS of the α-methylene aromatic araminenone and aminoketones. The characteristic chemical shift of the olefinic protons in ^1H NMR is also discussed.
文摘Hydrogels of dimethylaminoethyl acrylate methyl chloride quaternary salt (Q9) have been synthesized with different monomer ratio by copolymerization of this poorly studied monomer either with acrylic acid or with 2-methylene bu-tane-1,4-dioic acid. Hydrogel swelling was measured as a function of the composition of the hydrogel and of the crosslinking agent ratio. High values of swelling have been obtained at very high crosslinking values (【14 wt %) and the equilibrium swelling was reached at very low time (less than 15 minutes). The swelling isotherms consisted of a steep initial portion and then levelled off as asymptotically to the equilibrium swelling limit. The experimental data suggest clearly that the swelling process obeys second-order kinetics. According to this, the kinetics rate constant and the equilibrium water content were determined at different comonomer composition and crosslinker concentration. The calculated kinetic constants ranged from 0.48 to 3.76 ×10-2 min-1 for poly (acrylic acid-co-Q9) hydrogels and from 0.68 to 4.0 ×10-2 min-1 for poly (2-methylene butane-1,4-dioic acid-co-Q9) hydrogels depending on the hydrogels composition. The diffusion process was evaluated for each hydrogel showing a non-Fickian type diffusion. In all cases was observed a considerable increase in diffusion coefficient as Q9 content increases.
文摘Two new sterol have been isolated from the South China Sea marine organism. Compound 1 was isolated from the sponge Polymastia sobustia and compound 2 was obtained from the soft coral Sinularia inexplicata. Their structures were established as 3 beta-hydroxy-stigmast-5en-7-one and 24-methylene cholestan -3 beta, 6 beta, 9 alpha, 19-tetrol by variety of spectral analysis such as IR, EIMS, 1DNMR, H-1-H-1 COSY, HMQC, HMBC, NOESY.
文摘A simple, efficient and low-cost methodology for the synthesis of α-aryl-α,β-unsaturated esters using paraformaldehyde as a source of carbon was developed. Factors that control reaction yields such as temperature, concentration and reaction time were evaluated. A mechanism is proposed based on experimental structures of the intermediates.
基金funded by Outstanding Youth Foundation of Heilongjiang province(NO.YQ2021H009).
文摘Objective: To isolate bioactive compounds from the endophytic fungus Fusarium sporotrichioides isolated from Rauwolfia yunnanensis, and investigate their pharmacological activities.Methods: The chemical constituents were isolated and purified by combining with ODS column chromatography, silica gel column chromatography and by performing semipreparative HPLC. Their structures were established on the basis of 1D NMR(1H-NMR and13C-NMR) and 2D NMR(1H–1H COSY,HSQC, HMBC and NOESY), as well as HRESIMS and comparison with literature data. In addition, the absolute configuration of compound 1 was determined by calculated ECD data.Results: One previously undescribed tetracyclic triterpenoid derivative, named as integracide L(1), 12aacetoxy-4,4-dimethyl-24-methylene-5a-cholesta-8,14-diene-2a,3β,11β-triol(2), 12a-acetoxy-4,4-dime thyl-24-methylene-5a-cholesta-8-momoene-2a,3β,11β-triol(3), 12a-acetoxy-4,4-dimethyl-24-methy lene-5a-cholesta-8,14-diene-3β,11β-triol(4), and 12a-acetoxy-4,4-dimethyl-24-methylene-5acholesta-8-momoene-3β,11β-triol(5) were isolated from F. sporotrichioide. Moreover, compound 1 was rare tetracyclic triterpenoid with single methyl replacement at C-4 position.Conclusion: Compound 1 was a new tetracyclic triterpenoid isolated from the endophytic fungus F.sporotrichioides. In addition, compound 2 could inhibit the growth of three different human cancer cells significantly. Compounds 3 and 5 were found to possess better cytotoxic activities on Hep G-2 cells than the other compounds, with IC50values of(2.8 ± 0.1) and(6.3 ± 0.3) μmol/L respectively.
文摘P2X_(1) receptors and adrenoceptors are mainly responsible for vasoconstriction in a variety of blood vessels.However,previous studies have shown that α,β-methylene adenosine 5'-triphosphate(α,β-MeATP),a stable analogue of ATP,can induce both pressor and depressor responses in la boratory animals.In this study,the effects of increasing intravenous doses of α,β-MeATP and noradrenaline(NA)(0-30 nmol/kg)administered at 20 min intervals on systolic(SBP),diastolic(DBP)and mean(MBP)blood pressure in groups of anesthetized mice(n=6)were compared.Both α,β-MeATP and NA caused transient,dose-dependent increases in SBP,DBP and MBP but the effect of α,β-MeATP was more rapid and significantly larger at doses of 10 and 30 nmol/kg(P<0.01).At the dose of 30 nmol/kg,α,β-MeATP increased SBP,DBP and MBP by 65.8±7.0,65.7±5.0 and 65.7±5.5 mmHg,respectively,compared to increases of 36.8±4.6,33.3±4.9 and 34.5±4.7 mmHg,respectively,produced by NA.These results indicate P2X_(1) receptors play an important role in BP regulation although purinergic vasoconstriction alone may not explain the more potent pressor response to α,β-MeATP in the anesthetized mouse.
