http://nopr.niscpr.res.in/handle/123456789/22260 2026-10-10T20:21:43Z http://nopr.niscpr.res.in/handle/123456789/22581 Title: Direct observation and structural investigation of galactomannans by transmission electron microscope Authors: Yongli, Yang; Shoujun, Guo; Kun, Sun; Ji, Zhang; Tianzhen, Ju; Jian, Yao Abstract: Galactomannans isolated from the seeds of <i>Ceratonia siliqua, Itelicise tetragonoloba </i>and <i>Sophora japonica </i>have been studied<i> </i>directly by transmission electron microscope and the fine structures<i> </i>of these galactomannans investigated. Although all the three<i> </i>types of galactomannans are linear, they can be distinguished<i> </i>from one another easily under transmission electron microscope. The results indicate that the fine structures of galactomannans<i> </i>vary with their origin. Generally, galactomannan from guar is<i> </i>non block-type, their α-<img src='http://www.niscair.res.in/jinfo/smaller.gif' border=0>-galactose side-chains are disposed basically<i> </i>regular; but not unifonnly. Unlike guar gum, the galactomannans<i> </i>from sophora bean gum and locust bean gum have<i> </i>block-type dispositions which are composed of alternately distributed<i> </i>smooth zone and hair zone but the smooth zone of locust<i> </i>bean gum is longer than that sophora bean gum. Page(s): 313-316 2000-04-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/22580 Title: Steroidal alkaloids from <i>Veratrum taliense</i> Authors: Zhou, C X; Tan, R X; Ye, W C; Min, Z D Abstract: Phytochemical reinvestigation of the roots and rhizomes of <i>Veratrum taliense </i>yield three known (solanidine,veramiline-3-<i>O</i>-β-<img src='http://www.niscair.res.in/jinfo/smaller.gif' border=0>-glucopyranoside and stenophylline B-3-<i>O</i>-β-<img src='http://www.niscair.res.in/jinfo/smaller.gif' border=0>-glucopyranoside) and two novel steroidal alkaloids. The structures of the new compounds have been established by a combination of spectroscopic methods as 3- angeloylzygadenine-β-<i>N</i>-oxide and (20<i>S</i>, 25<i>S</i>)-22,26-epiminocholesta-5,22-diene-3β,12α-diol (named veramitaline). The chemotaxonomic significance of the isolates are discussed briefly. Page(s): 283-286 2000-04-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/22517 Title: A novel naphthalene glucoside from <i>Cassia javanica </i>stem bark Authors: Sanghi, Rashmi; Singh, Rahul; Singh, J Abstract: A new glucoside, 3-carbomethoxynaphtho [1,2-<i>b</i>]-3',3'dimethylpyran-4-<i>O</i>-,<i>β</i>-glucopyranoside has been isolated from the stem bark of <i>Cassia javanica.</i> Page(s): 321-322 2000-04-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/22516 Title: Synthesis and antimicrobial activity of 2-substituted-6-chloro-8-nitro-4-trichloromethyl-4<i>H</i>-1,3,2-benzodioxaphosphorin 2-oxides Authors: Srinivasulu, D; Reddy, C Devendranath Abstract: A series of 2-aryloxy/2-arylthio-6-chloro-8-nitro-4-trichloromethyl-4<i>H</i>-1,3,2-benzodioxaphosphorin 2-oxides <b>3</b> have been synthesized by-reacting 2-(2,2,,2-trichloro-1-hydroxyethyl)-4-chloro-6-nitrophenol <b>1</b> with different arylphosphorodichloridates <b>2</b> in the presence of triethylamine at 70-80°C. Some of these compounds are prepared by reacting the monochloride, 2-chloro- 6-chloro-8-nitro-4-trichloromethyl-4<i>H</i>-1, 3, 2-benzodioxaphosphorin 2-oxide 4, <i>in situ </i>with substituted phenol and thiols <b>5</b>. The monochloride is prepared by condensing 2-(2,2,2-trichloro-1-hydroxyethyl)- 4-chloro-6-nitrophenol with phosphorus oxychloride. IR, ¹H, ¹³C and ³¹P NMR and mass spectral data have been discussed. Some of these compounds have been screened for their antibacterial and antifungal activities. Page(s): 317-320 2000-04-01T00:00:00Z