Phytochemical investigations from the roots of Cynanchum stauntonii led to obtain four new C_(21) steroidal glycosides(1–4) and one known compound stauntoside F(5). Their chemical structures were characterized ...Phytochemical investigations from the roots of Cynanchum stauntonii led to obtain four new C_(21) steroidal glycosides(1–4) and one known compound stauntoside F(5). Their chemical structures were characterized by sophisticated analyses of IR, HRESI-TOF-MS, 1D, and 2D-NMR data, together with chemical methods, which showed interesting 13,14:14,15-disecopregnane-type skeleton or 14,15-secopregnane-type skeleton C_(21) steroidal glycosides. Among them, compound 1 was determined to be glaucogenin C 3-O-b-D-glucopyranosyl-(1 → 4)-b-D-cymaropyranosyl-(1 → 4)-b-D-digitoxopyranosyl-(1 → 4)-b-D-thevetopyranoside. Compound 2 was characterized to be hirundigenin 3-O-a-L-diginopyranosyl-(1 → 4)-b-D-cymaropyranosyl-(1 → 4)-b-D-digitoxopyranosyl-(1 → 4)-b-D-30-demethyl-thevetopyranoside. Compound 3 was identified to be(14S,16 S,20R)-14,16-14,20-15,20-triepoxy-14,15-secopregn-5-en-3-ol-3-O-a-L-cymaropyranosyl-(1 → 4)-b-D-digitoxopyranosyl-(1 → 4)-b-D-oleandropyranoside.Compound 4 was identified to be(14S,16 S,20R)-14,16-14,20-15,20-triepoxy-14,15-secopregn-5-en-3-ol-3-O-a-L-cymaropyranosyl-(1 → 4)-b-D-cymaropyranosyl-(1 → 4)-b-D-digitoxopyranosyl-(1 → 4)-b-Dthevetopyranoside. Among them, compound 2 was hirundigenin type C21 steroidal glycoside that existed in nature as epimers due to the presence of 14-hemiketal hydroxyl group in its structure. In addition, the anti-inflammatory and cardiomyocyte protective effects of compounds 1–4 were evaluated. We found that they exhibited significant protective effects on hypoxia/reoxygenation induced cardiomyocyte injury, but did not showed obvious anti-inflammatory function.展开更多
High-performance superamphiphobic fabrics are very useful in special fields,such as firefighting,rescue,and polar sports.The complicated preparation process,easily damaged surface structure,and high cost drastically l...High-performance superamphiphobic fabrics are very useful in special fields,such as firefighting,rescue,and polar sports.The complicated preparation process,easily damaged surface structure,and high cost drastically limit their commercial application.In this work,we utilized a simple,low-cost superamphiphobic coating to prepare a superamphiphobic aramid fabric(SAF).The excellent repellency to acid/alkali solutions and low boiling point organic solvents has been demonstrated with the contact angle of>150°and>130°,respectively.Additionally,the original color of the fabric can also be maintained,accompanied by superior flame retardancy,strength and comfort with thermal degradation of 361℃.More importantly,SAF displayed excellent durability via 50 standard machine washes,100-min of ultrasonic washing,10-min of UV irradiation,120-min of high-temperature heating,5000 cycles of abrasion,and destructive abrasion by sharp metal.All the results showed the superior performance of our SAF in protective fabrics under extreme environmental conditions.展开更多
基金supported by grants from Science and Technology Planning Project of Guangdong Province,China(No.2015B030301005)
文摘Phytochemical investigations from the roots of Cynanchum stauntonii led to obtain four new C_(21) steroidal glycosides(1–4) and one known compound stauntoside F(5). Their chemical structures were characterized by sophisticated analyses of IR, HRESI-TOF-MS, 1D, and 2D-NMR data, together with chemical methods, which showed interesting 13,14:14,15-disecopregnane-type skeleton or 14,15-secopregnane-type skeleton C_(21) steroidal glycosides. Among them, compound 1 was determined to be glaucogenin C 3-O-b-D-glucopyranosyl-(1 → 4)-b-D-cymaropyranosyl-(1 → 4)-b-D-digitoxopyranosyl-(1 → 4)-b-D-thevetopyranoside. Compound 2 was characterized to be hirundigenin 3-O-a-L-diginopyranosyl-(1 → 4)-b-D-cymaropyranosyl-(1 → 4)-b-D-digitoxopyranosyl-(1 → 4)-b-D-30-demethyl-thevetopyranoside. Compound 3 was identified to be(14S,16 S,20R)-14,16-14,20-15,20-triepoxy-14,15-secopregn-5-en-3-ol-3-O-a-L-cymaropyranosyl-(1 → 4)-b-D-digitoxopyranosyl-(1 → 4)-b-D-oleandropyranoside.Compound 4 was identified to be(14S,16 S,20R)-14,16-14,20-15,20-triepoxy-14,15-secopregn-5-en-3-ol-3-O-a-L-cymaropyranosyl-(1 → 4)-b-D-cymaropyranosyl-(1 → 4)-b-D-digitoxopyranosyl-(1 → 4)-b-Dthevetopyranoside. Among them, compound 2 was hirundigenin type C21 steroidal glycoside that existed in nature as epimers due to the presence of 14-hemiketal hydroxyl group in its structure. In addition, the anti-inflammatory and cardiomyocyte protective effects of compounds 1–4 were evaluated. We found that they exhibited significant protective effects on hypoxia/reoxygenation induced cardiomyocyte injury, but did not showed obvious anti-inflammatory function.
基金supported by the National Key R&D Program of China(Grant No.2016YFC0802802)。
文摘High-performance superamphiphobic fabrics are very useful in special fields,such as firefighting,rescue,and polar sports.The complicated preparation process,easily damaged surface structure,and high cost drastically limit their commercial application.In this work,we utilized a simple,low-cost superamphiphobic coating to prepare a superamphiphobic aramid fabric(SAF).The excellent repellency to acid/alkali solutions and low boiling point organic solvents has been demonstrated with the contact angle of>150°and>130°,respectively.Additionally,the original color of the fabric can also be maintained,accompanied by superior flame retardancy,strength and comfort with thermal degradation of 361℃.More importantly,SAF displayed excellent durability via 50 standard machine washes,100-min of ultrasonic washing,10-min of UV irradiation,120-min of high-temperature heating,5000 cycles of abrasion,and destructive abrasion by sharp metal.All the results showed the superior performance of our SAF in protective fabrics under extreme environmental conditions.