To develop new tumor targeting macromolecular conjugates,poly（HPMA）-SD-APMA-DTPA（HPMA：N-（2-hydroxypropyl）- methacrylamide;APMA：N-（3-ammopropyl）methacrylamide;DTPA：diethylenetriaminepentaacetic acid;SD：sulfadiazine） was synthesized and characterized.The poly（HPMA）-SD-DTPA conjugates were radiolabeled with the radionuclide ^（99m）Tc and tested for uptake by cultured H22 cells in vitro.DTPA-^（99m）Tc（radiotracer 1） and poly（HPMA）-DTPA-^（99m）Tc（radiotracer 2） were also synthesized and characterized for comparison.The uptake of poly（HPMA）-SD-DTPA-^（99m）Tc（radiotracer 3,34.76%） was significantly higher than that of poly（HPMA）-DTPA-^（99m）Tc（16.40%）,indicating that uptake of the poly（HPMA）-SD-DTPA-^（99m）T was active binding.The uptake of poly（HPMA）-DTPA-^（99m）Tc was significantly higher than that of DTPA-^（99m）Tc（2.98%）, suggesting that uptake of the poly（HPMA）-DTPA-^（99m）T was passive binding.The data suggest that the poly（HPMA）-SDAPMA -DTPA conjugates might be useful as tumor targeting macromolecular conjugates.
A new α-diimine ligand 1a, bis[N,N′-（4-tert-butyl-2,6-dimethylphenyl）imino]-2,3-butanediylidene and its corresponding Ni（II） complex 2a, {bis[N,N′-（4-tert-butyl-2,6-dimethylphenyl）imino]-2,3-butanediylidene}dibromo- nickel were successfully synthesized, and characterized by 1H NMR, 13C NMR, Fourier transform infrared spectroscope（FTIR）, elemental analysis and X-ray photoelectron spectroscopy（XPS）. α-Diimine ligand 1b, bis[N,N′-（2,6- dimethylphenyl）imino]-2,3-butanediylidene and its corresponding Ni（II） complex 2b, {bis[N,N′-（2,6-dimethyl- phenyl）imino]-2,3-butanediylidene}dibromonickel were also synthesized and characterized for comparison. The pre-catalyst 2a with sterically bulky, electron-donating group tert-butyl, activated by diethylaluminum chloride （DEAC） and tested in the polymerization of ethylene, was very highly active[2.01×107 g PE/（mol Ni？h？0.1 MPa）] and led to a very highly branched polyethylene（ca. 35―103 branches/1000 C）. The state of the polyethylene obtained varied from plastic, elastomer polymers to the oil-like hyperbranched polymers.
YUAN Jian-chao LIU Yu-feng MEI Tong-jian WANG Xue-hu
