6778-50-3Relevant articles and documents
New steroidal saponins from the roots of Solanum melongena L.
Yang, Bing-You,Yin, Xin,Liu, Yan,Zhao, Dong-Ying,Kuang, Hai-Xue
, p. 12 - 19 (2018/05/22)
Phytochemical investigation of the roots of Solanum melongena L. resulted in the isolation of six new steroidal saponins, including five new cholestane saponins (1-5) and one new steroidal alkaloid (6), along with one new natural product (7) and three know steroids (8-10). The structures of all isolated compounds were determined by 1D and 2D NMR experiments and by comparison of their spectroscopic and physical data with literature values. The inhibitory activities on nitric oxide (NO) production stimulated by lipopolysaccharide (LPS) in a RAW 264.7 cell line were assayed for all the isolated compounds. Compounds 1, 2 and 4–9 exhibited moderate inhibition of NO production with IC50 values ranging from 12.6 to 59.5 μM.
Trifasciatosides A-J, steroidal saponins from Sansevieria trifasciata
Teponno, Rémy Bertrand,Tanaka, Chiaki,Jie, Bai,Tapondjou, Léon Azefack,Miyamoto, Tomofumi
, p. 1347 - 1355 (2016/09/09)
Four previously unreported steroidal saponins, trifasciatosides A-D (1-4), three pairs of previously undescribed steroidal saponins, trifasciatosides E-J (5a, b-7a, b) including acetylated ones, together with twelve known compounds were isolated from the n-butanol soluble fraction of the methanol extract of Sansevieria trifasciata. Their structures were elucidated on the basis of detailed spectroscopic analysis, including 1H-NMR, 13C-NMR, 1H-1H correlated spectroscopy (COSY), heteronuclear single quantum coherence (HSQC), heteronuclear multiple bond connectivity (HMBC), total correlated spectroscopy (TOCSY), nuclear Overhauser enhancement and exchange spectroscopy (NOESY), electrospray ionization-time of flight (ESI-TOF)-MS and chemical methods. Compounds 2, 4, and 7a, b exhibited moderate antiproliferative activity against HeLa cells.
Microwave-assisted one-pot synthesis of 1,6-anhydrosugars and orthogonally protected thioglycosides
Ko, Yen-Chun,Tsai, Cheng-Fang,Wang, Cheng-Chung,Dhurandhare, Vijay M.,Hu, Pu-Ling,Su, Ting-Yang,Lico, Larry S.,Zulueta, Medel Manuel L.,Hung, Shang-Cheng
, p. 14425 - 14431 (2014/12/10)
Living organisms employ glycans as recognition elements because of their large structural information density. Well-defined sugar structures are needed to fully understand and take advantage of glycan functions, but sufficient quantities of these compounds cannot be readily obtained from natural sources and have to be synthesized. Among the bottlenecks in the chemical synthesis of complex glycans is the preparation of suitably protected monosaccharide building blocks. Thus, easy, rapid, and efficient methods for building-block acquisition are desirable. Herein, we describe routes directly starting from the free sugars toward notable monosaccharide derivatives through microwave-assisted one-pot synthesis. The procedure followed the in situ generation of per-O-trimethylsilylated monosaccharide intermediates, which provided 1,6-anhydrosugars or thioglycosides upon treatment with either trimethylsilyl trifluoromethanesulfonate or trimethyl(4-methylphenylthio)silane and ZnI2, respectively, under microwave irradiation. We successfully extended the methodology to regioselective protecting group installation and manipulation toward a number of thioglucosides and the glycosylation of persilylated derivatives, all of which were conducted in a single vessel. These developed approaches open the possibility for generating arrays of suitably protected building blocks for oligosaccharide assembly in a short period with minimal number of purification stages.
