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Histone deacetylases (HDACs) play an essential role in the transcriptional regulation of cells through the deacetylation of nuclear histone and non-histone proteins and are promising therapeutic targets for the treatment of various diseases. Here, the synthesis of new compounds in which a hydroxamic acid residue is attached to differently substituted pyrimidine rings via a methylene group bridge of varying length as potential HDAC inhibitors is described. The target compounds were obtained by alkylation of 2-(alkylthio)pyrimidin-4(3H)-ones with ethyl 2-bromoethanoate, ethyl 4-bromobutanoate, or methyl 6-bromohexanoate followed by aminolysis of the obtained esters with hydroxylamine. Oxidation of the 2-methylthio group to the methylsulfonyl group and following treatment with amines resulted in the formation of the corresponding 2-amino-substituted derivatives, the ester group of which reacted with hydroxylamine to give the corresponding hydroxamic acids. The synthesized hydroxamic acids were tested as inhibitors of the HDAC4 and HDAC8 isoforms. Among the synthesized pyrimidine-based hydroxamic acids N-hydroxy-6-[6-methyl-2-(methylthio)-5-propylpyrimidin-4-yloxy]hexanamide was found to be the most potent inhibitor of both the HDAC4 and HDAC8 isoforms, with an IC50 of 16.6 µM and 1.2 µM, respectively.

Human carbonic anhydrase (CA) IX has emerged as a promising anticancertarget and a diagnostic biomarker for solid hypoxic tumors. Novel fluorinated CAIX inhibitors exhibited up to 50 pM affinity towards the recombinant human CA IX,selectivity over other CAs, and direct binding to Zn(II) in the active site of CA IXinducing novel conformational changes as determined by X-ray crystallography. Massspectrometric gas-analysis confirmed the CA IX-based mechanism of the inhibitors ina CRISPR/Cas9-mediated CA IX knockout in HeLa cells. Hypoxia-induced extracellularacidification was significantly reduced in HeLa, H460, MDA-MB-231, and A549 cellsexposed to the compounds, with the IC50 values up to 1.29 nM. A decreased clonogenicsurvival was observed when hypoxic H460 3D spheroids were incubated with ourlead compound. These novel compounds are therefore promising agents for CA IXspecifictherapy.

Alkaline phosphatase from E. coli was immobilized on Sepharose-4B, macroporous cellulose and chitosan-based carriers. The yields of immobilization were over 60% in most cases. It was shown that immobilized alkaline phosphatase can be used for dephosphorylation of DNA 5'-termini.

Human carbonic anhydrase IX (CA IX) is highly expressed in tumor tissues, and its selective inhibition provides a potential target for the treatment of numerous cancers. Development of potent, highly selective inhibitors against this target remains an unmet need in anticancer therapeutics. A series of fluorinated benzenesulfonamides with substituents on the benzene ring was designed and synthesized. Several of these exhibited a highly potent and selective inhibition profile against CA IX. Three fluorine atoms significantly increased the affinity by withdrawing electrons and lowering the pKa of the benzenesulfonamide group. The bulky ortho substituents, such as cyclooctyl or even cyclododecyl groups, fit into the hydrophobic pocket in the active site of CA IX but not CA II, as shown by the compound's co-crystal structure with chimeric CA IX. The strongest inhibitor of recombinant human CA IX's catalytic domain in human cells achieved an affinity of 50 pM. However, the high affinity diminished the selectivity. The most selective compound for CA IX exhibited 10 nM affinity. The compound that showed the best balance between affinity and selectivity bound with 1 nM affinity. The inhibitors described in this work provide the basis for novel anticancer therapeutics targeting CA IX.

S-Alkylation of pyrimidine derivatives (I) with ω-bromoacetylbenzenesulfonamides (II) and (IV) affords the title compounds (III) and (V), respectively.

ß-galactosidase from Penicillium canescens was immobilized on chitosan, sepharose-4B, foamable polyurethane and some other carriers. The highest yield of immobilization (up to 98 %) was obtained by using chitosan as a carrier. The optimum pH and temperature were not significantly altered by immobilization. High stability of immobilized ß-galactosidase during storage was demonstrated. Efficient lactose saccharification (over 90 %) in whey was achieved by using immobilized ß-galactosidase. (C) Central European Science Journals. All rights reserved.

Enzymatic hydrolysis of lactose at 5°C was proposed for production of low lactose milk. Stability of milk casein particles was decreased and their dispersity was increased as a results of lactose conversion. Immobilized β-galactosidase was successfully tested for lactose hydrolysis in whey.