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A synthetic strategy to efficiently prepare main-chain peptide-polymer conjugates probing their aggregation in solution is described. An in situ tandem reaction based on aminolysis/thio-bromo "click" reaction is performed to tether an amyloidogenic peptide fragment amyloid-β (Leu-Val-Phe-Phe (LVFF)) to the ω-chain end of poly(diethylene glycol methyl ether acrylate) (PDEGA), prepared via reversible addition fragmentation chain transfer polymerization. Structural confirmation of the constructed conjugates PDEGA-LVFF (M = 5600, Ð = 1.21), (M = 7600, Ð = 1.16), and (M = 8900, Ð = 1.15) is successfully made by combined studies of H NMR, size-exclusion chromatography, matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry, and electrospray ionization time-of-flight (ESI-TOF) mass spectrometry. The effect of the peptidic constituent on the thermoresponsive behavior of the polymer is examined by UV-vis spectroscopy, and the self-assembly behavior of the amphiphilic conjugate is further exploited, exhibiting micellar morphology in aqueous solution.

Chiral and achiral β-turn mimetic polymer conjugates were synthesized, and their chiroptical properties were investigated. Chiral helical poly(n-hexyl isocyanate)s (PHICs) with alkyne functional end groups (4.0−5.4 kDa) were synthesized via coordination polymerization using either a chiral or an achiral alkyne-functional organotitanium catalyst. The obtained helical polymers were coupled with a chiral β-turn mimetic structure using the copper-catalyzed azide/alkyne cycloaddition (CuAAC) reaction, in turn allowing to tune the distance between the PHIC-helix and the chiral center from 7 to 14 Å. The successful linkage of the PHIC-helix to the β-turn mimetic was confirmed by size exclusion chromatography (SEC), high performance liquid chromatography (HPLC), 1 H NMR spectroscopy, and MALDI-ToF mass spectrometry, proving the attachment of either one or two PHIChelices to the central β-turn. Circular dichroism (CD) spectra confirmed chirality induction from the chiral β-turn mimetic structure to the polymer backbone of the achiral PHIC over five chemical bonds via postpolymerization modification, and revealed a distance-dependent effect for the transmission of stereochemical information. In contrast, a linkage effect leading to reduced chirality was observed when an additional linker unit was incorporated in-between the β-turn mimetic structure and the polymer backbone. The reported data do show that transfer of chirality is possible after polymerization over a relatively short distance of atoms.