92403-95-7Relevant academic research and scientific papers
Poly(ethylene glycol) with Multiple Aldehyde Functionalities Opens up a Rich and Versatile Post-Polymerization Chemistry
Blankenburg, Jan,Maciol, Kamil,Hahn, Christoph,Frey, Holger
, p. 1785 - 1793 (2019/02/27)
Two novel epoxide monomers 3,3-dimethoxy-propanyl glycidyl ether (DMPGE) and 3,3-dimethoxy-2,2-dimethylpropanyl glycidyl ether (DDPGE) were developed for the introduction of multiple aldehyde functionalities into the poly(ethylene glycol) (PEG) backbone. The acetal protecting group for the aldehyde functionality is stable against the harsh, basic conditions of the anionic ring-opening polymerization. Both monomers could be homopolymerized as well as copolymerized randomly with ethylene oxide (EO) in a controlled fashion. Copolymers with molecular weights (Mn) in the range of 4500-20100 g/mol and low dispersity (Mw/Mn) between 1.06 and 1.14 were obtained. The polymers were characterized by size exclusion chromatography, 1H NMR spectroscopy, and by differential scanning calorimetry regarding their thermal properties. The controlled character of the copolymerization was verified by MALDI-TOF. To study the distribution of the acetal-protected aldehyde functionalities at the polyether chains, the copolymerization with EO was monitored by in situ 1H NMR kinetics experiments for both monomers. These measurements revealed almost ideally random distribution of the comonomers with reactivity ratio pairs rEO = 0.96, rDMPGE = 1.04 and rEO = 1.20, rDDPGE = 0.83. The acetal functionalities of DMPGE polymers were successfully addressed by hydrazone formation. In addition, DDPGE copolymers were successfully deprotected in acidic media, and various transformations yielded aldehyde-, ester-, and nitrile-functionalized PEG while maintaining a dispersity below 1.1. Consequently, these monomers represent promising building blocks for the synthesis of multifunctional PEG for a variety of biomedical purposes.
FUSED HETEROCYCLIC COMPOUND
-
Page/Page column 93, (2011/07/29)
The present invention relates to a fused heterocyclic compound having the Formula 1, which is useful as a platelet aggregation inhibitor, a method for preparing the same, and a pharmaceutical composition for inhibiting platelet aggregation comprising the same.
Transformations of chromanol and tocopherol and synthesis of ascorbate conjugates
Lahmann, Martina,Thiem, Joachim
experimental part, p. 1654 - 1664 (2011/04/18)
α-Tocopherol and as a model compound pentamethylchromanol could be transferred into simple and more complex 5a-ether derivatives including galactopyranose as well as ascorbic acid conjugates. Following elaboration of a glucopyranoside spacer element this could be used for tethering the vitamin E and the vitamin C components to give novel conjugates for subsequent biostudies concerning their proposed synergism of antioxidant properties in tissues.
REGIO- AND STEREO-SELECTIVITIES IN THE TITANIUM COMPLEX CATALYZED HYDROBORATION OF CARBON-CARBON DOUBLE BONDS IN VARIOUS UNSATURATED COMPOUNDS
Lee, Hyung Soo,Isagawa, Kakuzo,Toyoda, Hiromu,Otsuji, Yoshio
, p. 673 - 676 (2007/10/02)
The titanium complex prepared from TiCl3 and NaBH4 in THF in the presence of 18-crown-6 promotes the catalytic hydroboration of carbon-carbon double bonds in alkenes, alkadienes and unsaturated ethers with NaBH4, giving sodium organoborates which can be converted into alcohols by oxidation with H2O2/CH3ONa.The reaction proceeds with high regio- and stereo-selectivities.
