Several stigamasterol saponins were concisely synthesized. Name!y, four monosaccharide （glucopyranose, galactopyranose, xylopyranose, 2-acetamido-2-deoxy-a-D-glucopyranose）, lactopyranose and chacotriose were couple...Several stigamasterol saponins were concisely synthesized. Name!y, four monosaccharide （glucopyranose, galactopyranose, xylopyranose, 2-acetamido-2-deoxy-a-D-glucopyranose）, lactopyranose and chacotriose were coupled with 3-OH of stigmasterol. All the compounds were identified by NMR, IR and high resolusion MS.展开更多
3-O-[β-D-Glucopyranosyl-（1→3）-α-L-arabinopyranosyl]-oleanolic acid-28-O-[β-D-glucopyranosyl] ester 1 was synthesized concisely by a convergent strategy. Using stepwise fashion for the synthesis of saponin 2, 3-O...3-O-[β-D-Glucopyranosyl-（1→3）-α-L-arabinopyranosyl]-oleanolic acid-28-O-[β-D-glucopyranosyl] ester 1 was synthesized concisely by a convergent strategy. Using stepwise fashion for the synthesis of saponin 2, 3-O-{[β-D-glucopyranosyl-（1→2）]-[α-L-arabinopyranosyl-（1→3）]-α-L-arabinopyranosyl）-oleanolic acid-28-O-（β- D-glucopyranosyl） ester, an abnormal phenomenon, that the terminal arabinosyl residue took the ^1C4 conformation instead of typical ^4C1 form, was observed. Deprotection or heating could not resume the normal conformation, which resulted in the product of 2＇ not 2.展开更多
One of the analogues of icogenin, a natural furostanol saponin showing strong cytotoxic effect on cancer cell, was first synthesized via convergent strategy by using diosgenin and available monosaccharides as starting...One of the analogues of icogenin, a natural furostanol saponin showing strong cytotoxic effect on cancer cell, was first synthesized via convergent strategy by using diosgenin and available monosaccharides as starting materials.展开更多
New saponin 26-O-tert-butyldimethylsiliyl protodiosgenyl β-D-glucopyranoside 1 was synthesized and its cytotoxicity activity in vitro was evaluated by MTI＇. It showed potent antitumor activity to human cancer cells....New saponin 26-O-tert-butyldimethylsiliyl protodiosgenyl β-D-glucopyranoside 1 was synthesized and its cytotoxicity activity in vitro was evaluated by MTI＇. It showed potent antitumor activity to human cancer cells. E ring and C22-OH play important roles in the antitumor activity of 1. A method to selective removal of acetyl group in the presence of benzoyl group was reported.展开更多
CT Traditional Chinese medicine （TCM） is a huge treasure trove for the discovery and development of modern pharmaceuticals. Indeed, numerous biologically and pharmacologically significant molecules have been identif...CT Traditional Chinese medicine （TCM） is a huge treasure trove for the discovery and development of modern pharmaceuticals. Indeed, numerous biologically and pharmacologically significant molecules have been identified from TCM; among them, a considerable portion belongs to glycosides. These glycosides are extremely diverse in structures, consisting of a large variety of aglycones, glycans, as well as glycosidic linkages. In addition, these glycosides occur frequently as a complicated mixture of congeners in the nature sources. This micro-heterogeneity leads to the isolation of a ho- mogeneous glycoside in an appreciable amount a formidable task. Therefore, development of synthetic approaches toward these nature glycosides has received great attention. In this account, we summarize our twenty-year efforts spent on this topic. Fifty five representative TCM-relevant glycosides synthesized by our group are highlighted. Based on the aglycone structure, these glycosides are categorized into three groups, i.e., steroid glycosides, triterpene glycosides, and flavonoid and phenolic glycosides. Typical synthetic approaches are discussed, showing the demanding tactics for regio- and stereo-controlled installation of glycans and overall manipulation of protecting groups. These expedient and scalable synthetic approaches have provided practical alternatives to the accessibility of these TCM components and thus opportunities for their in depth biological and pharmacological studies.展开更多
The focus of this work is the synthesis of an ursolic acid saponin with an N-acetylglucosamine-containing trisaccharide residue. Therefore, ursolic acid 3-yl α-L-arabinopyranosyl-（1→2）-α-L-arabinopyranosyl-（1→6...The focus of this work is the synthesis of an ursolic acid saponin with an N-acetylglucosamine-containing trisaccharide residue. Therefore, ursolic acid 3-yl α-L-arabinopyranosyl-（1→2）-α-L-arabinopyranosyl-（1→6）-2- acetamido-2-deoxy-β-D-glucopyranoside （1） was concisely synthesized in convergent synthesis with 48.0% overall yield. The structure of saponin 1 was confirmed by ^1H NMR, ^13C NMR and mass spectra.展开更多
基金Project supported by the National Natural Science Foundation of China （No. 30400564）.
文摘Several stigamasterol saponins were concisely synthesized. Name!y, four monosaccharide （glucopyranose, galactopyranose, xylopyranose, 2-acetamido-2-deoxy-a-D-glucopyranose）, lactopyranose and chacotriose were coupled with 3-OH of stigmasterol. All the compounds were identified by NMR, IR and high resolusion MS.
基金Project supported by the National Natural Science Foundation of China （No. 30400564） and National High Technology Research and Development Program of China （863 Program） （No. 2003AA624060）.
文摘3-O-[β-D-Glucopyranosyl-（1→3）-α-L-arabinopyranosyl]-oleanolic acid-28-O-[β-D-glucopyranosyl] ester 1 was synthesized concisely by a convergent strategy. Using stepwise fashion for the synthesis of saponin 2, 3-O-{[β-D-glucopyranosyl-（1→2）]-[α-L-arabinopyranosyl-（1→3）]-α-L-arabinopyranosyl）-oleanolic acid-28-O-（β- D-glucopyranosyl） ester, an abnormal phenomenon, that the terminal arabinosyl residue took the ^1C4 conformation instead of typical ^4C1 form, was observed. Deprotection or heating could not resume the normal conformation, which resulted in the product of 2＇ not 2.
基金the National Natural Science Foundation of China （No 20372085） .
文摘One of the analogues of icogenin, a natural furostanol saponin showing strong cytotoxic effect on cancer cell, was first synthesized via convergent strategy by using diosgenin and available monosaccharides as starting materials.
基金Financial support of this research by the National Natural Science Foundation of China(No 20372085)is gratefully acknowledged by the authors.
文摘New saponin 26-O-tert-butyldimethylsiliyl protodiosgenyl β-D-glucopyranoside 1 was synthesized and its cytotoxicity activity in vitro was evaluated by MTI＇. It showed potent antitumor activity to human cancer cells. E ring and C22-OH play important roles in the antitumor activity of 1. A method to selective removal of acetyl group in the presence of benzoyl group was reported.
基金BY. is grateful to his co-workers whose names appear in the references for their invaluable contributions to this topic of researches, and to the current financial support from the National Natural Science Foundation of China （21432012 ＆ 21621002）, the Strategic Priority Research Program of the Chinese Academy of Sciences （XDB20020000）, and the K. C. Wong Education Foundation （E09013）.
文摘CT Traditional Chinese medicine （TCM） is a huge treasure trove for the discovery and development of modern pharmaceuticals. Indeed, numerous biologically and pharmacologically significant molecules have been identified from TCM; among them, a considerable portion belongs to glycosides. These glycosides are extremely diverse in structures, consisting of a large variety of aglycones, glycans, as well as glycosidic linkages. In addition, these glycosides occur frequently as a complicated mixture of congeners in the nature sources. This micro-heterogeneity leads to the isolation of a ho- mogeneous glycoside in an appreciable amount a formidable task. Therefore, development of synthetic approaches toward these nature glycosides has received great attention. In this account, we summarize our twenty-year efforts spent on this topic. Fifty five representative TCM-relevant glycosides synthesized by our group are highlighted. Based on the aglycone structure, these glycosides are categorized into three groups, i.e., steroid glycosides, triterpene glycosides, and flavonoid and phenolic glycosides. Typical synthetic approaches are discussed, showing the demanding tactics for regio- and stereo-controlled installation of glycans and overall manipulation of protecting groups. These expedient and scalable synthetic approaches have provided practical alternatives to the accessibility of these TCM components and thus opportunities for their in depth biological and pharmacological studies.
基金Project supported by the National Natural Science Foundation of China （No. 30400564）.
文摘The focus of this work is the synthesis of an ursolic acid saponin with an N-acetylglucosamine-containing trisaccharide residue. Therefore, ursolic acid 3-yl α-L-arabinopyranosyl-（1→2）-α-L-arabinopyranosyl-（1→6）-2- acetamido-2-deoxy-β-D-glucopyranoside （1） was concisely synthesized in convergent synthesis with 48.0% overall yield. The structure of saponin 1 was confirmed by ^1H NMR, ^13C NMR and mass spectra.
