Synthesis And Chiral Self-assembly Of Phospholipid Coils

Phospholipid molecules with the amphiphilic property can self-assemble and form phospholipid spiral tubes with a certain spatial structure under a special condition.The phospholipid spiral tube has a broad application prospect in many fields becasuse of many unique physical and chemical properties.Accordingly,it is significant to study the effect of the phospholipid molecular structure on its self-assembly.If the biacetylene phospholipid tubule is formed by the self-assembly of phospholipid molecules with the different chirality,the swirling lines with a left handed spiral band and a right-handed spiral band can appear on the surface of the tube.However,there has always been an unresolved problem on self-assembly study so far:Is the spiral-band tube with the different rotation orientation formed by a single chiral phospholipid molecule,or is it assembled toghther by a large number of the single chiral molecules and a small number of chiral molecules with the opposite configuration?Thus,we have proposed the way to combine the fluorescent dye with phospholipid molecules by the chemical synthesis method,so as to trace the self-assembly process of phospholipid spiral tubes by dye marking.Above all,we intented to realize the combination of fluorescent dyes and phospholipid molecules via the reaction to form the amide bond between carboxyl group and amino group.On the one hand,fluorescent dyes of Cy3 and Cy5 with carboxyl structure were designed and synthesized successfully through the multi-step synthesis reaction.On the other hand,the synthetic route of phospholipid molecule with amino structure was designed,and then the fluorescent dye Cy5 was combined with phospholipid molecule intermediates by three different schemes.However,owing to the fragility of the intermediates structure,the phospholipid molecule with amino structure intermediates can’t been synthesized successfully.The expected goal has not been achieved.Therefore,we have carried out the other two research projects.Secondly,both a waist-type monomer（WMA）with maleimide structure and a tail-type styrene monomer（TSB）were designed and synthesized successfully.Using the characteristics of alternating copolymerization between styrene and maleimide,the novel alternating copolymer of Co（WMA-TSB）with side-chain liquid mesogenic units was prepared successfully via the free radical copolymerization of WMA and TSB,whose structure was confirmed through ¹H NMR,¹³C NMR and GPC.It showed that Co（WMA-TSB）was a smectic liquid crystal with the clearing point of 125oC by means of polarizing microscope（POM）,differential thermal scanner（DSC）,small angle X-ray scattering（SAXS）and two dimensional small angle X-ray scattering（2D-SAXS）.Based on the thermogravimetric ananlysis（TGA）,Co（WMA-TSB）had the better heat stability.Thirdly,a novel hydrogen-bonding complementary Compound 9 was designed and synthesized successfully,which was further combined with melamine in a 3:1stiochimetry.As a result,a new kind of hydrogen-bonding compound Complex Mel-9with melamine-core was successfully obtained by ultrasonic treament and annealing.