- Synthesis and characterisation of new types of side chain cholesteryl polymers
-
A series of cholesterol derivatives have been synthesised via the alkylation reaction of the 3-hydroxyl group with the aliphatic bromide compounds with different chain lengths, namely 3β-alkyloxy-cholesterol. The double bond between the C5 and C6 positions in these cholesterol derivatives was oxidised into epoxy, followed by an epoxy-ring-opening reaction with the treatment with acrylic acid, resulting in a series of 3β-alkyloxy-5α- hydroxy-6β-acryloyloxycholesterol, CnOCh (n = 1, 2, 4, 6, 8, 10, 12), The acrylate group is connected to the C6 position, which is confirmed by the single crystal structure analysis. The corresponding polymers, PC nOCh, were prepared via free radical polymerisation. The structure of monomers and the resulting polymers were characterised with nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR) and gel permeation chromatography (GPC). The thermal properties of PCnOCh were studied using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). To determine the secondary structure of polymers, circular dichroism (CD) spectra were performed. It was found that not all monomers produce high-molecular-weight polymers because of steric hindrance. However, all polymers have a helical structure, which can be enhanced by increasing the alkoxy chain length. In addition, increasing the alkoxy chain length decreases the glass transition temperature and increases the decomposition temperature of the polymers.
- Wang, Bin,Du, Haiyan,Zhang, Junhua
-
-
Read Online
- Montmorillonite Clay Catalysis. Part 13.1 Etherification of Cholesterol Catalysed by Montmorillonite K-10
-
The preparation of cholesteryl ethers from alcohols and phenols with cholesterol is carried out at 50-70 °C by using montmorillonite K-10 as an acid catalyst in chloroform or cyclohexane.
- Lu, Bo,Li, Li-Jun,Li, Tong-Shuang,Li, Ji-Tai
-
p. 604 - 605
(2007/10/03)
-
- SOLVOLYSIS OF 3β-CHLORO-5-CHOLESTENE IN THE PRESENCE OF ZINC SALTS
-
When heated in alcohols in the presence of zinc chloride 3β-chloro-5-cholestene undergoes solvolysis, and cholesterol ethers are formed with high yields.The same direction of reaction is preserved if the zinc chloride is formed directly in the reaction mixture.
- Kutulya, L. A.,Oleinik, S. S.,Protsenko, L. I.,Tishchenko, V. G.
-
p. 1467 - 1469
(2007/10/02)
-
- The Synthesis of Cholesteryl Alkyl Ethers
-
Seventeen cholesteryl alkyl ethers were synthesized through alcoholysis of cholesterol p-toluenesulfonate.This method was found superior to the etherification of sodium or potassium cholesterylate with alkyl halides or methanesulfonates, especially for the preparation of long-chain unsaturated alkyl ethers of cholesterol of high specific activity.
- Halperin, G.,Gatt, S.
-
-