56543-17-0Relevant academic research and scientific papers
Hydrophobic, Hydrophilic, and Amphiphilic Polyglycocarbonates with Linear and Macrocyclic Architectures from Bicyclic Glycocarbonates Derived from CO2 and Glucoside
Pati, Debasis,Feng, Xiaoshuang,Hadjichristidis, Nikos,Gnanou, Yves
, p. 1362 - 1370 (2017)
Two bicyclic glycocarbonates were synthesized in five steps from α-methyl-d-glucoside without resorting to phosgene or to its derivatives for the first time. The 4- and 6-positions of glucose were modified to introduce a six-membered carbonate ring, using CO2 as the carbonylating reagent; the 2- and 3-positions of the same glucoside substrate were first transformed into either methyl or triethylene glycol monomethyl ether groups to protect these positions from undesirable reactions and also to impart hydrophobicity in the first case and hydrophilicity in the second. The polymerization behavior of these bicyclic glycocarbonates was then investigated under different conditions. On the one hand, through ring-opening polymerization of the above monomers, linear polyglycocarbonate homopolymers and diblock copolymers were obtained initiated by p-methylbenzyl alcohol using 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) as catalyst; on the other hand, macrocyclic polyglycocarbonate homopolymers and diblock copolymers were grown using 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) which served as zwitterionic initiator. The various architectures derived were all thoroughly characterized by NMR, GPC, and MALDI-tof and shown to exhibit the expected structure. Finally, the self-assembly of linear and macrocyclic amphiphilic copolyglycocarbonates in water was investigated and characterized by cryo-TEM.
STEREOSELETIVITIES IN THE REACTIONS OF α-D-HEXOPYRANOSID-4-ULOSES WITH DIAZOMETHANE
Sato, Ken-Ichi,Yoshimura, Juji
, p. 221 - 238 (2007/10/02)
The stetreoselectivities in the reactions of diazomethane with various α-D-hexopyranosid-4-uloses are compared with those in Grignard reactions.The results support the hypothesis that the stereoselectivity of the diazomethane reaction is mainly controlled
CHAIN ELONGATION BY USE OF AN IRON CARBONYL REAGENT: A FACILE SYNTHESIS OF 6-DEOXYHEPTOSIDURONIC ACIDS
Baer, Hans H.,Hanna, Hanna R.
, p. 169 - 184 (2007/10/02)
A method of chain elongation at the nonreducing terminal of 6-deoxy-6-halo- and 6-O-tosyl-hexopyranosides, to give methyl (methyl 6-deoxyheptopyranosid)uronates was developed on the basis of organo-iron chemistry.Thus, methyl 2,3,4-tri-O-acetyl-6-O-p-toly
Further Stereoselective Reductions of 3-O-Hexafuranosyl S-Methyl Dithiocarbonates with Tributyltin Deuteride. A Comment on Mechanism
Fuller, Trevor S.,Stick, Robert V.
, p. 2509 - 2515 (2007/10/02)
The reduction of 1,2:5,6-di-O-isopropylidene-3-O-(methylthio)thiocarbonyl-β-D-altrose, -mannose and -(3-2H)mannose with tributyltin deuteride and hydride leads to highly stereoselective syntheses of 3-deoxy-1,2:5,6-di-O-isopropylidene-β-D-(3-2H)altrose and -(3-2H)mannose.In addition, the reduction of a pair of diastereomeric dithiocarbonates with virtually no stereochemical constraints leads to the same diastereomeric mixture of reduced products, indicating a common radical intermediate for the reduction.
