Familial dysautonomia is a debilitating congenital neurodegenerative disorder with no causative therapy. It is caused by a homozygous mutation in ELP1 gene, resulting in the production of the transcript lacking exon 20. The compounds studied as potential treatments include the clinical candidate kinetin, a plant hormone from the cytokinin family. We explored the relationship between the structure of a set of kinetin derivatives (N = 72) and their ability to correct aberrant splicing of the ELP1 gene. Active compounds can be obtained by the substitution of the purine ring with chlorine and fluorine at the C2 atom, with a small alkyl group at the N7 atom, or with diverse groups at the C8 atom. On the other hand, a substitution at the N3 or N9 atoms resulted in a loss of activity. We successfully tested a hypothesis inspired by the remarkable tolerance of the position C8 to substitution, postulating that the imidazole of the purine moiety is not required for the activity. We also evaluated the activity of phytohormones from other families, but none of them corrected ELP1 mRNA aberrant splicing. A panel of in vitro ADME assays, including evaluation of transport across model barriers, stability in plasma and in the presence of liver microsomal fraction as well as plasma protein binding, was used for an initial estimation of the potential bioavailability of the active compounds. Finally, a RNA-seq data suggest that 8-aminokinetin modulates expression spliceosome components.

• Klíčová slova
• ADME in vitro, Alternative splicing, Cytokinin, ELP1, Kinetin, mRNA metabolism,
• MeSH
• kinetin * farmakologie   chemie   MeSH
• lidé MeSH
• molekulární struktura MeSH
• prekurzory RNA * genetika   metabolismus   MeSH
• sestřih RNA * účinky léků   MeSH
• transkripční elongační faktory metabolismus   genetika   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• Elp1 protein, human MeSH Prohlížeč
• kinetin * MeSH
• prekurzory RNA * MeSH
• transkripční elongační faktory MeSH

A novel group of 5,6-dihydropyrido [2',1':2,3]imidazo [4,5-c]quinolines was prepared via a microwave assisted one-pot telescopic approach. The synthetic sequence involves the formation of an amine precursor of imidazo [1,2-a]pyridine via condensation and reduction under microwave irradiation. Subsequently, the Pictet-Spengler cyclisation reaction occurs with ketones (cyclic or acyclic) to obtain substituted 5,6-dihydropyrido [2',1':2,3]imidazo [4,5-c]quinolines in excellent yields. The compounds were tested as neuroprotective agents. Observed protection of neuron-like cells, SH-SY5Y differentiated with ATRA, in Parkinson's and Huntington's disease models inspired further mechanistic studies of protective activity against damage induced by 1-methyl-4-phenylpyridinium (MPP+), a compound causing Parkinson's disease. The novel compounds exhibit similar or higher potency than ebselen, an established drug with antioxidant activity, in the cells against MPP + -induced total cellular superoxide production and cell death. However, they exhibit a significantly higher capacity to reduce mitochondrial superoxide and preserve mitochondrial membrane potential. We also observed marked differences between a selected derivative and ebselen in terms of normalizing MPP + -induced phosphorylation of Akt and ERK1/2. The cytoprotective activity was abrogated when signaling through cannabinoid receptor CB2 was blocked. The compounds also inhibit both acetylcholine and butyrylcholine esterases. Overall the data show that novel 5,6-dihydropyrido [2',1':2,3]imidazo [4,5-c]quinoline have a broad cytoprotective activity which is mediated by several mechanisms including mitoprotection.

• Klíčová slova
• Choline esterase, Microwave-assisted synthesis, Mitochondria, Neurodegeneration, One-pot synthesis, Parkinson's disease, Telescopic approach,
• MeSH
• chinoliny * farmakologie   chemie   chemická syntéza   MeSH
• cholinesterasové inhibitory * farmakologie   chemie   chemická syntéza   MeSH
• lidé MeSH
• molekulární struktura MeSH
• nádorové buněčné linie MeSH
• neuroprotektivní látky * farmakologie   chemie   chemická syntéza   MeSH
• receptor kanabinoidní CB2 * metabolismus   antagonisté a inhibitory   MeSH
• signální transdukce * účinky léků   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• chinoliny * MeSH
• cholinesterasové inhibitory * MeSH
• neuroprotektivní látky * MeSH
• receptor kanabinoidní CB2 * MeSH

In this paper, we present the synthesis of four new complexes: the dimeric precursor [Ir(dmppz)2(μ-Cl)]2 (1) (Hdmppz - 3,5-dimethyl-1-phenyl-1H-pyrazole) and heteroleptic bis-cyclometalated complexes: [Ir(dmppz)2(Py2CO)]PF6·½CH2Cl2 (2), [Ir(dmppz)2(H2biim)]PF6·H2O (3), and [Ir(dmppz)2(PyBIm)]PF6 (4), with auxiliary N,N-donor ligands: 2-di(pyridyl)ketone (Py2CO), 2,2'-biimidazole (H2biim) and 2-(2'-pyridyl)benzimidazole (PyBIm). In the obtained complexes, SC-X-ray analysis revealed that Ir(III) has an octahedral coordination sphere with chromophores of the type {IrN2C2Cl2} (1) or {IrN4C2} (2-4). The complexes obtained, which have been fully characterised by physicochemical methods (CHN, TG, FTIR, UV-Vis, PL and 1H, 13C, 15N NMR), were used to continue our studies on the factors influencing the cytotoxic properties of potential chemotherapeutic agents (in vitro). To this end, the following studies are presented: (i) comparative analysis of the effects on the biological properties of N,N-donor ligands and C,N-donor ligands in the studied complexes, (ii) studies of the interactions of the compounds with the selected molecular target: DNA and BSA (UV-Vis, CD and PL methods), (iii) and the reactivity towards redox molecules: GSH, NADH (UV-Vis and/or ESI-MS methods), (iv) cytotoxic activity (IC50) of potential chemotherapeutics against MCF-7, K-562 and CCRF-CEM cell lines.

• MeSH
• antitumorózní látky * farmakologie   chemie   chemická syntéza   MeSH
• DNA chemie   metabolismus   MeSH
• fotochemické procesy MeSH
• iridium * chemie   farmakologie   MeSH
• komplexní sloučeniny * farmakologie   chemie   chemická syntéza   MeSH
• kvantová teorie MeSH
• léky antitumorózní - screeningové testy MeSH
• lidé MeSH
• ligandy MeSH
• molekulární modely MeSH
• molekulární struktura MeSH
• nádorové buněčné linie MeSH
• proliferace buněk * účinky léků   MeSH
• pyrazoly * chemie   farmakologie   chemická syntéza   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antitumorózní látky * MeSH
• DNA MeSH
• iridium * MeSH
• komplexní sloučeniny * MeSH
• ligandy MeSH
• pyrazole MeSH Prohlížeč
• pyrazoly * MeSH

Cytokinin oxidase/dehydrogenase (CKX) inhibitors reduce the degradation of cytokinins in plants and thereby may improve the efficiency of agriculture and plant tissue culture-based practices. Here, we report a synthesis and structure-activity relationship study of novel urea derivatives concerning their CKX inhibitory activity. The most active compounds showed sub-nanomolar IC50 values with maize ZmCKX1, the lowest value yet documented. Other CKX isoforms of maize and Arabidopsis were also inhibited very effectively. The binding mode of four compounds was characterized based on high-resolution crystal complex structures. Using the soil nematode Caenorhabditis elegans, and human skin fibroblasts, key CKX inhibitors with low toxicity were identified. These compounds enhanced the shoot regeneration of Lobelia, Drosera, and Plectranthus, as well as the growth of Arabidopsis and Brassica napus. At the same time, a key compound (identified as 82) activated a cytokinin primary response gene, ARR5:GUS, and a cytokinin sensor, TCSv2:GUS, without activating the Arabidopsis cytokinin receptors AHK3 and AHK4. This strongly implies that the effect of compound 82 is due to the up-regulation of cytokinin signalling. Overall, this study identifies highly effective and easily prepared CKX inhibitors with a low risk of environmental toxicity for further investigation of their potential in agriculture and biotechnology.

• Klíčová slova
• Agriculture, Arabidopsis, CKX inhibitor, biostimulant, biotechnology, cytokinin, cytokinin oxidase/dehydrogenase, diphenylurea, nutrient use efficiency, oilseed rape,
• MeSH
• Arabidopsis * účinky léků   genetika   MeSH
• Brassica napus genetika   účinky léků   MeSH
• cytokininy metabolismus   MeSH
• inhibitory enzymů farmakologie   MeSH
• kukuřice setá účinky léků   genetika   růst a vývoj   MeSH
• oxidoreduktasy * metabolismus   genetika   MeSH
• rostlinné proteiny metabolismus   genetika   chemie   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• zemědělství MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cytokinin oxidase MeSH Prohlížeč
• cytokininy MeSH
• inhibitory enzymů MeSH
• oxidoreduktasy * MeSH
• rostlinné proteiny MeSH

OBJECTIVES: This study aimed to characterise compounds with activity against carbapenemase-expressing Gram-negative bacteria and nematodes and evaluate their cytotoxicity to non-cancerous human cells. METHODS: The antimicrobial activity and toxicity of a series of phenyl-substituted urea derivatives were evaluated using broth microdilution, chitinase, and resazurin reduction assays. RESULTS: The effects of different substitutions present on the nitrogen atoms of the urea backbone were investigated. Several compounds were active against Staphylococcus aureus and Escherichia coli control strains. Specifically, derivatives 7b, 11b, and 67d exhibited antimicrobial activity against Klebsiella pneumoniae 16, a carbapenemase-producing Enterobacteriaceae species, with minimum inhibitory concentration (MIC) values of 100, 50, and 72 µM (32, 64, and 32 mg/L), respectively. In addition, the MICs obtained against a multidrug-resistant E. coli strain were 100, 50, and 36 µM (32, 16, and 16 mg/L) for the same compounds, respectively. Furthermore, the urea derivatives 18b, 29b, 50c, 51c, 52c, 55c-59c, and 62c were very active towards the nematode Caenorhabditis elegans. CONCLUSIONS: Testing on non-cancerous human cell lines suggested that some of the compounds have the potential to affect bacteria, especially helminths, with limited cytotoxicity to humans. Given the simplicity of synthesis for this class of compounds and their potency against Gram-negative, carbapenemase-expressing K. pneumoniae, aryl ureas possessing the 3,5-dichloro-phenyl group certainly warrant further investigation to exploit their selectivity.

• Klíčová slova
• Anthelmintic, Antibacterial, Aryl urea, Caenorhabditis elegans, Carbapenemase,
• MeSH
• anthelmintika * chemie   farmakologie   toxicita   MeSH
• antibakteriální látky * chemie   farmakologie   toxicita   MeSH
• Bacteria * účinky léků   genetika   MeSH
• bakteriální proteiny genetika   MeSH
• beta-laktamasy genetika   MeSH
• buněčné linie MeSH
• Caenorhabditis elegans účinky léků   MeSH
• cizopasní červi * účinky léků   MeSH
• fenylmočovinové sloučeniny * chemie   farmakologie   toxicita   MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• anthelmintika * MeSH
• antibakteriální látky * MeSH
• bakteriální proteiny MeSH
• beta-laktamasy MeSH
• carbapenemase MeSH Prohlížeč
• fenylmočovinové sloučeniny * MeSH

Isoprenoid cytokinins are a class of naturally occurring plant signaling molecules. A series of prepared compounds derived from isoprenoid cytokinins (isopentenyladenine, trans-zeatin and cis-zeatin) with attached 2'-deoxy-d-ribose or 2',3'-dideoxy-d-ribose at the N9 position of the purine were prepared and their biological activities were examined. Different synthetic approaches were employed. The final compounds were characterized with variety of physicochemical methods (TLC, HPLC-MS, and NMR) and their cytokinin activity was determined in classical bioassays such as Amaranthus, tobacco callus, detached wheat leaf senescence and Arabidopsis thaliana root elongation inhibition assay. In addition, compounds were screened for activation of the cytokinin signaling pathway (bacterial receptor, competitive ligand binding and ARR5::GUS assay) to provide a detailed assessment of CK structure-activity relationship. The prepared compounds were found to be non-toxic to human cells and the majority of assays exhibited the highest activity of free bases while 2',3'-dideoxyribosides had very weak or no activity. In contrast to the free bases, all 2'-deoxyriboside derivatives were not toxic to tobacco callus even at the highest tested concentration (10-4 moL/l) and compound 1 (iPdR) induced betacyanin synthesis at higher concentration even stronger than iP free base in the Amaranthus bioassay. The general cytokinin activity pattern base > riboside >2'-deoxyriboside > 2',3'-dideoxyriboside was distinguished.

• Klíčová slova
• Biological activity, Cytokinin 2′,3′-dideoxyriboside, Cytokinin 2′-deoxyriboside, Cytotoxicity, Isoprenoid cytokinin, Synthesis,
• MeSH
• cytokininy * farmakologie   MeSH
• lidé MeSH
• ribosa MeSH
• terpeny * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cytokininy * MeSH
• ribosa MeSH
• terpeny * MeSH

• Publikační typ
• tisková chyba MeSH

Solubility of growth regulators is essential for their use in agriculture. Four new cytokinin salts─6-benzylaminopurine mesylate (1), 6-(2-hydroxybenzylamino)purine mesylate (2), 6-(3-hydroxybenzylamino)purine mesylate (3), and 6-(3-methoxybenzylamino)purine mesylate (4)─were synthesized, and their crystal structures were determined to clarify structural influence on water solubility. The mesylates were several orders of magnitude more water-soluble than the parent CKs. The new salts significantly reduced chlorophyll degradation and impairment of photosystem II functionality in barley leaf segments undergoing artificial senescence and had pronounced effects on the leaves' endogenous CK pools, maintaining high concentrations of functional metabolites for several days, unlike canonical CKs. A foliar treatment with 1 and 3 increased the harvest yield of spring barley by up to 8% when compared to treatment with the parent CKs while also increasing the number of productive tillers. This effect was attributed to the higher bioavailability of the mesylate salts and the avoidance of dimethyl sulfoxide exposure.

• Klíčová slova
• antisenescence, bioavailability, crystal structure, cytokinin, endogenous cytokinins, grain yield, mesylates, photosynthesis influence, photosystem, solubility, spring barley,
• MeSH
• cytokininy * metabolismus   farmakologie   MeSH
• fotosyntéza MeSH
• ječmen (rod) * metabolismus   MeSH
• listy rostlin metabolismus   MeSH
• methansulfonáty metabolismus   MeSH
• soli MeSH
• voda metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cytokininy * MeSH
• methansulfonáty MeSH
• soli MeSH
• voda MeSH

A small library of 2-[(1H-indol-3-yl)methyl]-5-(alkylthio)-1,3,4-oxadiazoles was prepared, starting from indole-3-acetic acid methyl ester and its 5-methyl-substituted derivative. The synthetic route involved the formation of intermediate hydrazides, their condensation with carbon disulfide, and intramolecular cyclization to corresponding 5-[(1H-indol-3-yl)methyl]-1,3,4-oxadiazole-2(3H)-thiones. The latter were then S-alkylated, and in case of ester derivatives, they were further hydrolyzed into corresponding carboxylic acids. All 5-[(1H-indol-3-yl)methyl]-1,3,4-oxadiazole-2(3H)-thiones and their S-alkylated derivatives were then screened for their protective effects in vitro and in vivo. Methyl substitution on the indole ring and propyl, butyl, or benzyl substitution on sulfhydryl group-possessing compounds were revealed to protect Friedreich's ataxia fibroblasts against the effects of glutathione depletion induced by the γ-glutamylcysteine synthetase inhibitor, buthionine sulfoximine. Two of the active compounds also reproducibly increased the survival of Caenorhabditis elegans exposed to juglone-induced oxidative stress.

• Klíčová slova
• Caenorhabditis elegans, Friedreich's ataxia, indole, oxadiazole, oxidative stress,
• MeSH
• acetáty chemická syntéza   MeSH
• antioxidancia * chemická syntéza   chemie   farmakologie   MeSH
• Caenorhabditis elegans MeSH
• Friedreichova ataxie farmakoterapie   metabolismus   patologie   MeSH
• indoly * chemie   farmakologie   MeSH
• kultivované buňky MeSH
• kyseliny indoloctové chemie   MeSH
• lidé MeSH
• oxadiazoly * chemická syntéza   chemie   farmakologie   MeSH
• oxidační stres účinky léků   MeSH
• thioketony * chemická syntéza   chemie   farmakologie   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• acetáty MeSH
• antioxidancia * MeSH
• indole MeSH Prohlížeč
• indoleacetic acid MeSH Prohlížeč
• indoly * MeSH
• kyseliny indoloctové MeSH
• oxadiazoly * MeSH
• thioketony * MeSH

Kinetin (N6-furfuryladenine), a plant growth substance of the cytokinin family, has been shown to modulate aging and various age-related conditions in animal models. Here we report the synthesis of kinetin isosteres with the purine ring replaced by other bicyclic heterocycles, and the biological evaluation of their activity in several in vitro models related to neurodegenerative diseases. Our findings indicate that kinetin isosteres protect Friedreich́s ataxia patient-derived fibroblasts against glutathione depletion, protect neuron-like SH-SY5Y cells from glutamate-induced oxidative damage, and correct aberrant splicing of the ELP1 gene in fibroblasts derived from a familial dysautonomia patient. Although the mechanism of action of kinetin derivatives remains unclear, our data suggest that the cytoprotective activity of some purine isosteres is mediated by their ability to reduce oxidative stress. Further, the studies of permeation across artificial membrane and model gut and blood-brain barriers indicate that the compounds are orally available and can reach central nervous system. Overall, our data demonstrate that isosteric replacement of the kinetin purine scaffold is a fruitful strategy for improving known biological activities of kinetin and discovering novel therapeutic opportunities.

• Klíčová slova
• Cytokinin, Kinetin, Mitoprotection – familial dysautonomia, Neuroprotection, bioisostery – Friedreich́s ataxia,
• MeSH
• cytoprotekce MeSH
• kinetin chemická syntéza   chemie   farmakologie   MeSH
• kultivované buňky MeSH
• lidé MeSH
• molekulární struktura MeSH
• oxidační stres účinky léků   MeSH
• puriny chemická syntéza   chemie   farmakologie   MeSH
• viabilita buněk účinky léků   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kinetin MeSH
• purine MeSH Prohlížeč
• puriny MeSH