Search results for " prodrug"
showing 10 items of 22 documents
Synthesis and in vitro studies on a potential dopamine prodrug.
2008
Dopamine delivery to the central nervous system (CNS) undergoes the permeability limitations of blood-brain barrier (BBB) which is a selective interface that excludes most water-soluble molecules from entering the brain. Neutral amino acids permeate the BBB by specific transport systems. Conden- sation of dopamine with neutral amino acids could afford potential prodrugs able to interact with the BBB endogenous transporters and easily enter the brain. The synthesis and characterization of the dopamine derivative 2-amino-N-[2-(3,4-dihydroxy-phenyl)-ethyl]-3-phenyl-propionamide (7) is de- scribed. The chemical and enzymatic stability of 7 was evaluated. The molecular weight (300 Da) and Log P …
SYNTHESIS, PHYSICO-CHEMICAL AND BIOLOGICAL CHARACTERIZATION OF A PACLITAXEL MACROMOLECULAR PRODRUG
2004
Paclitaxel was attached to poly(hydroxyethylaspartamide) via a succinic spacer arm by a two-step protocol: (1) synthesis of 2'-O-succinyl-paclitaxel; (2) synthesis of PHEA-2'-O-succinyl-paclitaxel. The 2'-O-succinyl-paclitaxel derivative and the macromolecular conjugate were characterized by UV, IR, NMR and mass spectrometry analysis. The reaction yields were over 95% and the purity of products over 98%. Paclitaxel release and degradation from 2'-O-succinyl-paclitaxel occurred at a faster rate at pH 5.5 than 7.4. After 30 h of incubation at pH 5.5 and 7.4 the released free paclitaxel was about 40 and 20%, respectively. In plasma both drug release and degradation were found to occur at a hig…
Synthesis and analysis of activity of a potential anti-melanoma prodrug with a hydrazine linker
2013
A potential anti-melanoma prodrug containing a phenolic activator, a hydrazine linker, and a nitrogen mustard effector - (N-{4-[bis-(2-chloroethyl)amino]benzoyl}-N'-(4-hydroxybenzyl)hydrazine) has been synthesized in seven steps. Spectrophotometric measurements of its oxidation by tyrosinase showed a rapid increase of absorbance at 337 nm. HPLC analysis demonstrated that two major products were formed. However, during the reaction one of the products was converted into the other. The stable product with a maximum of absorption at 337 nm was isolated and identified as 5,6-dihydroxy-1H-indazol-1-yl 4-[bis-(2-chloroethyl)amino]benzoate. It was formed by a cyclization of the enzymatically gener…
Design, synthesis and biological evaluation of novel stilbene-based antitumor agents
2008
A series of novel stilbene derivatives has been synthesized and studied with the main goal to investigate SAR of the amino compound 1a, as well as to improve its water solubility, a potentially negative aspect of the molecule that could be a serious obstacle for a pre-clinical development. We have obtained derivatives with good cytotoxic activity, in particular, the derivatives 5c and 6b could represent two novel leads for further investigation. Compound 8b, a morpholino-carbamate derivative, prodrug of 1a, has a very good solubility in water, and is active in suppressing growth of tumor cells at a concentration of 5000 nM, which is a concentration 100 times higher than the parent stilbene …
Lipid nanocarriers containing esters prodrugs of Flurbiprofen. Preparation, physical-chemical characterization and biological studies.
2013
In this paper, the preparation, chemical-physical, technological and in vitro characterization of nanostructured lipid carriers (NLC) carrying R-flurbiprofen ester prodrugs, were analyzed for a potential pharmaceutical application. R-flurbiprofen was chosen as a model drug because it has been found to play an effective role in counteracting secretases involved in neurodegenerative diseases, although it does not cross the Blood Brain Barrier (BBB). In this study, two R-flurbiprofen ester prodrugs (ethyl and hexyl) were successfully synthesized and entrapped into non-pegylated and pegylated NLC. The obtained systems showed average diameters in the colloidal size range, negative zeta potential…
Evaluation of the aptitude to cross the BBB of a new dopamine aminoacidic prodrug
2012
One of the most important factors limiting the development of new drugs for the CNS is the ability to cross the BBB which is a barrier that controls the entrance and exit of both endogenous and exogenous compounds. BBB expresses several transport systems that carry actively into the brain important nutrients (e.g. glucose and amino acids) and are able to import or export various xenobiotics including drugs and their metabolites. The content of active in the brain depends on the overall difference between the drug uptake and drug efflux processes [1]. Dopamine (DA) is a crucial neurotransmitter; its striatal depletion is responsible of clinical signs of Parkinson’s disease (PD). Owing to the…
Preparation and characterization of lipid nanoparticles as potential carriers for ester prodrugs of flurbiprofen
2011
A new dopamine amino-acid conjugate: preclinical in vitro studies and evaluation of behavioural effects in rats
2012
It is well established that alterations in the functionality of dopaminergic transmission are associated with neurodegenerative diseases such as Parkinson’s Disease. The purpose of this study was to investigate the activity of a new dopamine amino-acid conjugate: L-phenylalanine-β-(3,4-dihydroxyphenyl) etilamide(DA-Phe) in the central nervous system, by assessing its influence on different behavioural parameters in the rat. Preliminarily, we tested the in vitro stability in plasmatic environment following the disappearance of DA-Phen from human plasma and the concurrent appearance of dopamine. Using rat brain homogenate, we also evaluated the level of DA-Phen cleavage by cerebral enzymes an…