Sclerotinia sclerotiorum, Helminthosprium maydis, Botrytis cinerea and Rhizoctonia solani are harmful pathogenic fungi of crops or vegetables 1-4. Over the past decades, synthetic fungicides including carbendazim have been used to prevent them. However, in recent years, they have developed resistance to the fungicides 5-9. Moreover, their scope of resistance continues to expand and has already included many new fungicides 10-12. Therefore, new fungicides are continually required. It is well-known that since aspirin (acetylsalicylic acid) was first marketed in 1899, it has been widely used for the treatment of pains, fever and colds 13-16. Therefore, in the present study, aspirin derivatives were synthesized based on aspirin. In the meantime, their antifungal activity has been evaluated in the laboratory to find new fungicides with high efficacy and low toxicity.

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Herein, we report a class of distinctive supramolecular nanostructures in situ-generated from the cationic ring-opening polymerization of a particular 2-oxazoline monomer, i.e., 2-( N - tert -butyloxycarbonylaminomethyl)-2-oxazoline (Ox1). Driven by side-chain hydrogen bonding between neighboring molecules and van der Waals interactions, the growing oligomers of Ox1 precipitate in the form of macroscopic platelets when the degree of polymerization reaches 5–7. A similar self-assembly occurred in the block copolymerization of 2-ethyl-2-oxazoline (EtOx) or 2-pentyl-2-oxazoline (PeOx) and Ox1 as the second monomer. These polymeric aggregates were found to disassemble into rod-like nanoparticles under appropriate conditions, and to form stable organogels in some polar solvents like dimethylformamide as well as in natural liquid fragrances such as ( R )-carvone, citronellal, and ( R )-limonene. Scanning electron microscopy revealed that the morphology of their xerogels was solvent-dependent, mainly with a lamellar or fibrous structure. The rheology measurements confirmed the as-obtained organogels feature an obvious thixotropic character. The storage modulus was about 7–10 times higher than the loss modulus, indicating the physical crosslinking in the gel. The fragrance release profiles showed that the presented supramolecular gel system exhibits good sustained-release effect for the loaded bioactive volatiles.

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