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We present the synthesis of polymeric nanoparticles from single ABA type block copolymers in an intramolecular-chain process to result 3-D architectures that confine a single chain of conducting copolymers. ABA triblock copolymers were prepared from conducting polymers such as fluorene homopolymers and fluorene/thiophene copolymers designed as telechelic macroinitiators to facilitate nitroxide-mediated living free radical polymerization methods. The polymerization with styrene and vinylbenzosulfone cross-linking units led to the desired ABA triblock copolymers with 8:1:8 and 5:1:5 ratios of the polymer copolymer blocks under living free radical polymerization conditions. In an intramolecular chain collapse process the ABA triblock copolymers form well-defined single chain nanoparticles with the confined semiconducting polymer block as core unit via a controlled cross-linking of the benzosulfone unit in the A block copolymer. The photoluminescence measurements illustrate the influence of the molecular weight of the A block to be crucial for the site isolation of the embedded conducting polymer block in the resulting nanoparticles with increased quantum efficiencies of 6%.

This Letter describes the synthesis and SAR, developed through an iterative analogue library approach, of an mGluR4 positive allosteric modulator lead based on a pyrazolo[3,4-d]pyrimidine scaffold. Despite tremendous therapeutic potential, Compound 7, VU0080421, and related congeners represent only a handful of mGluR4 positive allosteric modulators ever described.

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Substitution of –CD2– at the reactive centers of linoleic and linolenic acids reduces the rate of abstraction of D by a tocopheryl radical by as much as 36-fold, compared to the abstraction of H from a corresponding –CH2– center. This H atom transfer reaction is the rate-determining step in the tocopherol-mediated peroxidation of lipids in human low-density lipoproteins, a process that has been linked to coronary artery disease. The unanticipated large kinetic isotope effects reported here for the tocopherol-mediated oxidation of linoleic and linolenic acids and esters suggests that tunneling makes this process favorable.