1,2- Dihydroisoquinoline as a new carrier for specific delivery of drugs to the brain

The present thesis involves design, synthesis and investigation of a novel carrier system for .site-specific. delivery of biologically active compounds to the brain.. The. designed carrier is one of 1,2-dihydroisoquinoline  isoquinolinium salt redox chemical delivery system (Redox-CDS), that contains a carboxylic group at C(l) (1QCDS). The carboxylic group at this position was designed to enhance the rate of conversion of the lipophilic dihydrocompound to the corresponding quaternary (IQQ+). Molecular orbital calculations. were performed on the designed structures, their intermediates and expected transition states for reduction and oxidation reactions.The dissertation is divided into four main sections ; introduction, scope of investigation, results & discussion and experimental section.The introduction section is concerned with the methods used for .increasing drugs delivery to the brain, applications of 1,4-dihyDROPyridine as CDS {PCDS(s)} with certain drugs, the problems facing the use of dihyDROPyridine  pyridinium (PCDS PQ+) Redox-CDS in | pharmaceutical formulations and the aim of using dihydroquinoline, dihydroisoquinoline as brain-specific chemical delivery carriers.The scope of investigation states the main objectives of synthesis and design of IQCDS as a new chemical delivery system to the brain.The third section is devoted to discuss and describe the results obtained, the section is subdivided into four parts, the first part involves the discussion of the prepared intermediate compounds and the designed compound as a new CDS to the brain. Structures of the prepared compounds were confirmed by their melting or boiling points and spectral investigations as proton magnetic resonance (1H-NMR) and infrared.