Different generations of dendritic macromolecules based on triazine were synthesized by the divergent growth approach and functionalization with mesogenic units based on peripherally located dihydroxybiphenyl derivatives. Thermotropic liquid crystal dendrimers, containing poly (ethylene glycol) (PEG) as a core and triazine dendrons with peripherals mesogenic groups were synthesized. First generation (G1) was prepared by coupling of hydroxyl group of PEG with cyanuric chloride in dichloromethane at 0-5oC. Reaction of compound G1 with amino group of ethanolamine in dichloromethane resulted G1.5. Second generation of linear dendritic compounds (G2) was synthesized using coupling reaction of hydroxyl groups of compound G1.5 and cyanuric chloride in dichloromethane. Reaction of compound G2 with amino group of ethanolamine in water/dioxane resulted G2.5. The growth of dendrons on the PEG core and their structures were investigated using common spectroscopy methods. In the next step, compounds Cn with different alkyl tail groups were synthesized via nucleophilic displacement of bromine from 1-bromoalkane by potassium-4,4'-biphenoxide in DMF. The mesogenic compounds 4-bromo-(4-alkyloxybiphenyl-4'-oxy) butane (CnC4Br) were synthesized by reaction with Cn and 1,4-dibromobutane undergoing SN2 substitution. Liquid crystalline dendrimers (LCD) were synthesized via coupling of hydroxyl group of G2.5 and bromine from mesogenic units, 4-bromo-(4-alkyloxy-biphenyl-4'-oxy) butane. The liquid crystal property of mesogenic compound has been studied in details with differential scanning calorimetry and optical polarization microscopy. The experiments showed that the thermal properties are influenced with the spacer length.

Alzheimer’s disease (AD) is the most prevalent neurodegenerative disorder. It is characterized by formation of amyloid plaques and neurofibrillary tangles in the brain, degeneration of the cholinergic neurons and neural cell death. This study was aimed to investigate the effect of a triazine derivative, C16H12Cl2N3S, on learning in an Alzheimer’s rat model. Animals were divided into seven groups; each group contained seven animals. Control group: animals received no surgery and treatment; saline group: animals received normal saline after recovery; sham group: animals received 10% DMSO after recovery; STZ group (Alzheimer’s model): animals received streptozotocin (STZ) in four and six days after recovery; T5, T10 and T15 groups: animals were treated with triazine derivative, C16H12Cl2N3S, at doses of 5, 10 and 15 mM, respectively. All drugs were injected intracerebroventricular. The spatial learning and histological assessment were performed in all groups. Animals in STZ group had more deficits in spatial learning than the control group in Morris water maze. C16H12Cl2N3S improved spatial learning significantly compared to STZ group. The CA1 pyramidal layer thicknesses in STZ group were reduced significantly compared to control group. C16H12Cl2N3S increased the CA1 pyramidal layer thickness in T15 group compared to STZ group. Current findings suggest C16H12Cl2N3S may have a protective effect on learning deficit and hippocampal structure in AD.