Functionalization of polyethylene oxide with 4-amino- N-(2-pyrimidinyl) benzene sulfonamide at one end
✍ Scribed by Zhaohua Huang; Sheng Chen; Junlian Huang
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 190 KB
- Volume
- 73
- Category
- Article
- ISSN
- 0021-8995
No coin nor oath required. For personal study only.
✦ Synopsis
Polyethylene oxide (PEO) with 4-amino-N-(2-pyrimidinyl) benzene sulfonamide (APBS; PEO as ) at one end was used as a carrier polymer for attachment (via the hydroxyl end group) of drugs such as mustard. For this purpose, the amine group of PEO as was protected first by the formation of a Schiff's base; then protected PEO as OBr and PEO as ONH 2 were prepared. In order to attach N,N-dichloroethyl amine (DCEA) to the PEO as ONH 2 , DCEA hydrogen chloride salt was reacted with maleic anhydride first, then the resulting N,N-dichloroethyl maleinamic acid (DCEMA) could react with protected PEO as ONH 2 continuously in the presence of dicyclohexylcarbodiimide (DCC). However, DCEMA is unstable; the chloroethyl group was rearranged to a corresponding ternary ammonium salt with a three-membered ring (DCEMA r ). Therefore, the protected PEO as ONH 2 was coupled with the DCEMA r in the presence of DCC; then it attacked the nucleophilic center of the aniline group of the APBS end of the PEO as after deprotection. Thus, a PEO with higher molecular weight and wider distribution was formed due to the intermolecular addition of PEO as .