A Novel Approach for the Synthesis of<i>seco</i>C-Nucleoside Analogues
作者:Laila F. Awad、El Sayed H. El Ashry
DOI:10.1080/15257779908041493
日期:1999.4
The synthesis of 4-amino-3-(D-gluco- or D-galacto-pentitoi-1.yl)-5-mercapto-1,2,4-triazoles and their conversion to the respective 6-methyl-3-(1,2,3,4,5-penta-O-acetyl-pentitol-1-yl)1,2,4-triazolo[3,4-b] 1,3,4-thiadiazoles have been achieved. The vicinal coupling constants were used to deduce the favored conformations.
The crystal packing of N-(n-octyl)-d-gulonamide containing tail-to-tail sheets compared to its gluconamide diastereomer showing head-to-tail arrangement
作者:Christoph André、Peter Luger、Sönke Svenson
DOI:10.1016/s0008-6215(00)90511-1
日期:1992.6
N-Octylamides of diastereomeric gluconic and gulonic acids form molecular aggregates of extremely different curvature, namely helical micellar rods with a diameter of 4 nm and planar bilayers. In the crystal structure of the gulonamide compound, symmetric ''tail-to-tail'' bilayer sheets are observed, whereas the gluconamide derivative (whose crystal structure was determined previously) forms an unusual ''head-to-tail'' arrangement. These differences are unexpected because both diastereomers contain one pair each of syn- and anti-oriented hydroxyl groups in 1,3-positions of the extended aldonic acid chains. The experimental results are explained by the occurrence of hydrogen-bond patterns between hydroxyl groups, either within one crystal sheet or hydrophobic bilayer (gluconamide) or between the end groups of neighboring sheets (gulonamide).
MEINETSBERGER, EIKE
作者:MEINETSBERGER, EIKE
DOI:——
日期:——
HEIKKILA, HEIKKI OLAVI;NURMI, JUHA VEIKKO
作者:HEIKKILA, HEIKKI OLAVI、NURMI, JUHA VEIKKO
DOI:——
日期:——
BOUZARD, D.;PEROL, C.;STEMER, J.;WEBER, A.;GRANATEK, E. S.
作者:BOUZARD, D.、PEROL, C.、STEMER, J.、WEBER, A.、GRANATEK, E. S.