A new class of superabsorbent hydrogels was synthesized by copolymerization of acrylamide with sodium 4-hydroxy-2-methylene­butanoate (SHMB). SHMB is obtained by saponification of α-methylene-γ-butyrolactone (MBL) which is a renewable monomer from tulips. Radical polymerization of SHMB was studied for the first time. The extent of side products through the ring closure depended on the pH used during the polymerization. Reactivity ratios for copolymerization of SHMB with acrylamide were estimated. Prepared hydrogels with various composition were investigated for their swelling, mechanical and thermal properties, and morphology as well as cytotoxicity. The achieved degree of swelling of the hydrogels was up to 82 000% and significantly exceeds the capacity of classical superabsorbent hydrogels made of acrylamide and salts of acrylic acid. The degree of swelling as well as mechanical and thermal properties of the hydrogels could be tuned by SHMB content.

and reducing agent" ATRP. [4] It was also demonstrated that these systems are tolerant to molecular oxygen. [5] The limitation of all above mentioned ATRP variations working with ppm amounts of catalyst is that additional chemicals, used as reducing agents or radical precursors, and usually also quite expensive ligands, have to be added commonly at least tenfold excess related to catalyst. These chemicals and/or their oxidation products can participate in side reactions, even though the extent of the side reactions is significantly lower than that in "normal" ATRP.A photoATRP system, in which the copper(II) catalyst was reduced by light without necessity of using additional reducing agent, was reported for the first time by Yagci and co-workers. [6] In that work, however, equimolar amount of catalyst to initiator was used. In order to diminish the catalyst amount and at the same time to avoid using chemicals as reducing agents, our group reported for the first time a photoATRP system using Well-defined poly(methyl methacrylate) (PMMA) and poly(methyl acrylate) (PMA) are prepared via photochemically induced atom transfer radical polymerization (photoATRP) using ppm amounts of CuBr 2 /tris(2-pyridylmethyl)amine and CuBr 2 /tris[2-(dimethylamino)ethyl]amine catalyst complexes, respectively, without degassing of polymerization mixture and with no need to introduce an external reducing agent to the system. The effect of ligand to CuBr 2 ratio on kinetic and induction period during the polymerization of MMA and MA is investigated. The induction period is influenced also by the amount of oxygen in the polymerization system. Both the kinetics of MA polymerization and the induction period are affected by light intensity. Finally, the high livingness and initiation efficiency of the photoATRP system in the presence of air are proved by chain extension polymerizations. The presented system is valuable from an industrial point of view, since after optimization, well-defined and high-molarmass poly(meth)acrylates can be prepared without the necessity of degassing the system, while the polymerization can be proceeded quickly and without an induction period.

The practical stereodivergent route to both syn- and anti-diastereomers of 1-substituted 3-aminobutane-1,4-diols based on the crystallization-induced asymmetric transformation (CIAT) approach was completed. This led to the revision of the reported stereochemistry of the first inhibitor of CERT-dependent ceramide trafficking HPA-12 from (R,R)-anti- to the (R,S)-syn-enantiomer. Due to the expeditiousness of production and inexpensive conditions developed, a series of alkyl- and aryl-substituted analogues of HPA-12 is also reported.

A highly compartmentalized enzymatic network regulates the pro-apoptotic and proliferative effects of sphingolipids. Over-conversion of ceramide (Cer) correlates with insensitivity to apoptosis signaling (in response to chemotherapy) and to drug resistance of cancer cells. De novo sphingomyelin biosynthesis relies on non-vesicular ceramide trafficking by the CERT (CERamide Transfer) protein. Therefore, blocking CERT transfer, thus leading to increased intracellular ceramide availability, represents a potential anticancer strategy. Our study is based on the implementation of an in vitro binding assay, supported by in silico molecular docking. It constitutes the first attempt to explore at the molecular level for the identification of novel CERT ligands. This approach is the first step toward in silico design and optimization of CERT inhibitor candidates, potentially relevant as innovative ceramide-transfer-targeting therapeutic agents.

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Optimization of atom transfer radical polyadditions using commercially available catalytic systems allowed obtaining control over the polyester architecture and functionality and functional linear polyesters with high molecular weight (Mw = 16 200).

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