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1 2 3 4OO NHHNOClOOMeOO NHHNOClOOHH 2NOHNClOOHOO NHHNOONHOOMe5 6 7 8OClO NHHNOONHOOHH 2NOClHNONHOOHOOHNClONHOHNClOOMeOOHNClONHOHNClOOHClCl9 10 11 12H 2NONHOHNClOOOHNOMeOH O NH NHOOOOOHHNOHHN NHOHOOHNOHH 2N NHOO13 14 15 16OOHNONHOHNOOMeOOHNONHOHNOOHH 2NONHOHNOOHOOHNClONHOHNONHOOMeCl17 18OOHNClONHOHNONHOOHH 2NClONHOHNONHOOHClClFig. 2. Schematic representation of the molecular structures of the synthesized peptides.Figure 2 shows the structure of synthesized peptides. The ability of synthesized peptides tomake appropriate hydrogen bonding in aqueous media and organic solvents were investigated.First, the compounds were dried up completely and made into a fine powder usingultrasonication for five minutes. Then TFE solvent was added to the powder until it forms asaturated solution. White precipitates appear after adding water. With adjusting the pH, theprecipitate becomes soluble and by becoming more acidic, the precipitate formation wasincreased. In a particular pH the precipitates assemble completely and do not pour down byturning the container upside down (Figure 1-a). This point is absolutely temperaturedependent and the gel easily dissociates even with warmth from the hands. SEM results couldshow the nanostructure of the compounds 6 and 8 (Figure 1-b).Molecular dynamic calculations for compound 9 could show the high capabilities of thecompounds in establishing hydrogen bonds and appropriate π-stacking interactions (Figure 1-c). It seems, that tri- or tetra- peptides which contained γ-amino acids, the ability of hydrogenbonding could decrease, but on the other hand the helical structure of the products could bestable and therefore formation of π-stacking could increase.In conclusion, we described the synthesis of some novel peptides which contained one ortwo γ-amino acids in the sequence structure of desired peptides. The existence of γ-aminoacids could affect the self-assembly of the molecules and also the type of hydrogen bonding.The research for finding the biological activities of the synthesized peptides is in progress.AcknowledgmentsWe thank Iran Nanotechnology Initiative Council for financial support. We also acknowledge KimiaExir Company for chemical donation.References1. Petkova, A.T., Leapman, R.D., Guo, Z. Science 307, 262-265 (2005).2. Reches, M., Gazit, E. Science 300, 625-627 (2003).3. Gorbitz, C.H. Chem. Eur. J. 7, 5153 (2001).4. Reches, M., Gazit, E. Phys. Biol. 3, S10-S19 (2006).5. Andrew, M.S., et al. Adv. Mater. 20, 37-41 (2008).6. Castelletto, V., Hamley, L.W. Biophys. Chem. 141, 169-174 (2009).7. Schousboe, A., Sarup, A., Bak, L.H., Larsson, O.M., et al. Neurochem. Int. 45, 521-527 (2004).579