Eight novel diamino-ester ligands were synthesized by amidation reaction of long-chain alkyl esters of l-lysine with diethylenetriamine pentaacetic acid monoanhydride or ethylenediamine tetraacetic acid monoanhydride. The corresponding dimeric Gd(iii) complexes were obtained by treating these ligands with GdCl3·6H2O. All ligands and complexes were characterized by 1H NMR, FT-IR, and elemental analysis. The longitudinal relaxation time (T1) was measured, and all relaxivity values (R1) of these dimeric Gd(iii) complexes are higher than that of Magnivest (Gd-DTPA). One of these complexes, possessing the highest relaxivity in the DTPA series, was chosen to test the acute toxicity and T1-weighted imaging. It was found that this dimeric Gd(iii) complex exhibits no acute toxicity, and offers highly enhanced MRI signal and increases intention time in the rat liver tissue compared to Magnivest.
Poly(2-hexadecylsuccinic acid-sebacic acid) (P(HSA-SA)) copolymers have been prepared by melt polycondensation. The copolymers were characterized by FT-IR, 1 HNMR, gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). In vitro studies showed that all our prepared copolymers are degradable in phosphate buffer at 37 °C. The release profiles of hydrophilic model drug, ciprofloxcin hydrochloride, from the copolymers, follow first order release kinetics. All the preliminary results suggested that the copolymer might be potentially used as drug delivery devices.
A series of novel title compounds were synthesized by the addition reaction of trans 2-isothiocyano-4-substitutedphenyl-5, 5-dimethyl-1,3,2-dioxaphosphinane 2-sulfide to 3-aminomethylpyridine or 2-chloro-5-amino methylpyridine. Their structures were confirmed by 1 H NMR, 31 P NMR, IR, MS, and elemental analyses. Results of preliminary bioassay showed that all new compounds possess good fungicidal activity and insecticidal activity to some extent.
2-Octylsuccinic acid and its copolyanhydrides with sebacic acid have been synthesized by melt polycondensation, and were characterized by Fourier transform infrared spectroscopy, 1 H NMR, gel permeation chromatography, differential scanning calorimetry, and thermal gravimetric analysis. In vitro studies showed that all copolymers are degradable in phosphate buffer at 37 • C. The release profiles of the hydrophilic model drug ciprofloxacin hydrochloride follow first-order release kinetics.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.