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Considering that acetylcholinesterase (AChE) inhibition is the most important mode of action expected of a potential drug used for the treatment of symptoms of Alzheimer’s disease (AD), our previous pilot study of 4-aminoquinolines as potential human cholinesterase inhibitors was extended to twenty-two new structurally distinct 4-aminoquinolines bearing an adamantane moiety. Inhibition studies revealed that all of the compounds were very potent inhibitors of AChE and butyrylcholinesterase (BChE), with inhibition constants (Ki) ranging between 0.075 and 25 µM. The tested compounds exhibited a modest selectivity between the two cholinesterases; the most selective for BChE was compound 14, which displayed a 10 times higher preference, while compound 19 was a 5.8 times more potent inhibitor of AChE. Most of the compounds were estimated to be able to cross the blood–brain barrier (BBB) by passive transport. Evaluation of druglikeness singled out fourteen compounds with possible oral route of administration. The tested compounds displayed modest but generally higher antioxidant activity than the structurally similar AD drug tacrine. Compound 19 showed the highest reducing power, comparable to those of standard antioxidants. Considering their simple structure, high inhibition of AChE and BChE, and ability to cross the BBB, 4-aminoquinoline-based adamantanes show promise as structural scaffolds for further design of novel central nervous system drugs. Among them, two compounds stand out: compound 5 as the most potent inhibitor of both cholinesterases with a Ki constant in low nano molar range and the potential to cross the BBB, and compound 8, which met all our requirements, including high cholinesterase inhibition, good oral bioavailability, and antioxidative effect. The QSAR model revealed that AChE and BChE inhibition was mainly influenced by the ring and topological descriptors MCD, Nnum, RP, and RSIpw3, which defined the shape, conformational flexibility, and surface p

The influences of the application of mono- and two-component organic modifiers on lipophilicity determination of 12 tetradentate Schiff bases by reversed-phase thin layer chromatography were investigated. The main goal is to estimate types of interaction between observed compounds and components of the applied chromatographic systems and establish some behaviour pattern in order to easier choose a combination of organic modifiers which will simulate interaction in biological systems based on the facts that the same basic intermolecular interactions are responsible for the behaviour of substances in both the biological and chromatographic system. The applied organic modifier shows the ability to modify the surface of the applied sorbent, which affects the manifestation of lipophilicity of the observed compounds. Mono-component organic modifiers from different groups of the Snyder triangle were used, as well as their two-component mixtures. In addition, we compared experimentally determined calculated parameters of lipophilicity.

PaiIn this work, the influence of amide–π interactions on stability and properties of superoxide dismutase (SOD) active centres was analysed. In the data set of 43 proteins, 5017 amide–π interactions were observed, and every active centre formed averagely about 117 interactions. Most of the interactions belonged to the backbone of proteins. The analysis of the geometry of the amide–π interactions revealed two preferred structures, parallel-displaced and T-shaped structure. The aim of this study was to investigate the energy contribution resulting the from amide–π interactions, which were in the lower range of strong hydrogen bonds. The conservation patterns in the present study indicate that more than half of the residues involved in these interactions are evolutionarily conserved. The stabilization centres for these proteins showed that all residues involved in amide–π interactions were of use in locating one or more of such centres. The results presented in this work can be very useful for the understanding of contribution of amide–π interaction to the stability of SOD active centres., У овом раду је анализиран утицај амид–π интеракција на стабилност и особине активног центра супероксид-дисмутазe (SOD). Примећено је 5017 амид–π интеракција у сету података од 43 протеина, где, просечно, сваки активни центар формира 117 интер- акција. Већина интеракција је укључена у основни ланац протеина. Анализа геометрије амид–π интеракција открива две приоритетне структуре, паралелно-измештен (parallel- -displaced) и Т-облик (T-shaped) структуре. Ова студија има за циљ истраживање допри- носа енергије амид–π интеракција чије јачине су у доњем рангу јаких водоничних веза. Преглед конзервираности показује да је више од половине остатака укључених у ове интеракције еволутивно конзервирано. Стабилизациони центри ових протеина показују да су сви остаци који чине амид–_интеракције важни у распоређивању једног или више таквих центара. Свеукупно, резултати у овом раду ће бити врло корисни за разумевање доприноса амид–π интеракција када се анализира стабилност активних центара SOD.

The influences of the application of mono- and two-component organic modifiers on lipophilicity determination of 12 tetradentate Schiff bases by reversed-phase thin layer chromatography were investigated. The main goal is to estimate types of interaction between observed compounds and components of the applied chromatographic systems and establish some behaviour pattern in order to easier choose a combination of organic modifiers which will simulate interaction in biological systems based on the facts that the same basic intermolecular interactions are responsible for the behaviour of substances in both the biological and chromatographic system. The applied organic modifier shows the ability to modify the surface of the applied sorbent, which affects the manifestation of lipophilicity of the observed compounds. Mono-component organic modifiers from different groups of the Snyder triangle were used, as well as their two-component mixtures. In addition, we compared experimentally determined calculated parameters of lipophilicity.

Sveinsson's chorioretinal atrophy (SCRA) or helicoidal peripapillary chorioretinal degeneration (HPCD) as previously referred, is a rare ocular disease with autosomal dominant pattern of inheritance. The vast majority of reported cases were of Icelandic origin but the characteristic clinical picture of SCRA was also described in patients of non-Icelandic descent. Here, we report a novel disease-causing variant c.1261T>A, p.Tyr421Asn in TEAD1, detected in a Serbian family from Bosnia diagnosed with SCRA. The newly discovered change occurred at the same position as the “Icelandic mutation” (c.1261T>C, p.Tyr421His). According to our findings, this position in the exon 13 of the TEAD1 gene, at base pair 94, should be considered as a mutation hotspot and a starting point for future genetic analyses of patients with SCRA diagnosis.

In the present work, we examine the magnetic properties of 8 "end-to-end" thiocyanato, and 3 "end-to-end" cyanato double bridged Ni(II) binu­cle­ar complexes. Thiocyanato complexes are weakly ferromagnetic. Cyanato brid­ged complexes exhibit weak antiferromagnetic coupling. There­fore, it is a challenge for computational chemistry to calculate the exchange coupling constant in these systems accurately. 17 different Density Functional Approximations with different flavors are used to find the method of choice to study magnetic properties in binuclear Ni(II) complexes within the Broken-Symmetry approach. It is found that M06-2X and PWPB95 performed the best compared to experimental values for the entire set of examined complexes. Furthermore, the magneto-structural correlation rationalizes the results., У овом раду, проучавана су магнетна својства 8 "end-to-end" тиоцијанато, и 3 "end-to-end" цијанато двоструко премошћених Ni(II) бинуклеарних комплекса. Tиоцијанато премошћени комплекси су слабо феромагнетни. Комплекси премошћени цијанато лигандима показују слабо антиферомагнетно купловање. Због тога је прецизно израчунавање константи купловања у овим системима изазов за рачунарску хемију. Константе купловања у овим системима су израчунате Broken-Symmetry приступом у оквиру Теорије функционала густине. 17 апроксимативних функционала густине су коришћени како би се пронашао најпоузданији ниво теорије за проучавање магнетних својстава бинуклеарних Ni(II) комплекса. Утврђено је да су M06-2X и PWPB95 показали најбоље слагање са експерименталним вредностима за цео скуп испитиваних комплекса. Напослетку, резултати су рационализовани магнетно-структурном корелацијом.

Vaccines can have heterologous effects on the immune system, i.e., effects other than triggering an immune response against the disease targeted by the vaccine. We investigated whether monoclonal antibodies (mAbs) specific for tetanus could cross-react with Chlamydia and confer heterologous protection against chlamydial infection. The capability of two tetanus-specific mAbs, namely mAb26 and mAb51, to prevent chlamydial infection has been assessed: (i) in vitro, by performing a neutralization assay using human conjunctival epithelial (HCjE) cells infected with Chlamydia trachomatis serovar B, and (ii) in vivo, by using a guinea pig model of Chlamydiacaviae-induced inclusion conjunctivitis. The mAb26 has been superior in comparison with mAb51 in the prevention of chlamydial infection in HCjE cells. The mAb26 has conferred ≈40% inhibition of the infection, compared to less than 5% inhibition in the presence of the mAb51. In vivo, mAb26 significantly diminished ocular pathology intensity in guinea pigs infected with C. caviae compared to either the mAb51-treated or sham-treated guinea pigs. Our data provide insights that tetanus immunization generates antibodies which induce heterologous chlamydial immunity and promote protection beyond the intended target pathogen.

Chemical and biocatalytic synthesis of seven previously undescribed marchantin A ester derivatives has been presented. Chemical synthesis afforded three peresterified bisbibenzyl products (TE1-TE3), while enzymatic method, using lipase, produced regioselective monoester derivatives (ME1-ME4). The antiproliferative activities of all prepared derivatives of marchantin A were tested on MRC-5 healthy human lung fibroblast, A549 human lung cancer, and MDA-MB-231 human breast cancer cell lines. All tested esters were less cytotoxic in comparison to marchantin A, but they also exhibited lower cytotoxicity against healthy cells. Monoesters displayed higher cytotoxic activities than the corresponding peresterified products, presumably due to the presence of free catechol group. Monohexanoyl ester ME3 displayed the same IC50 like marchantin A against MDA-MB-231 cells, but the selectivity was higher. In this way, regioselective enzymatic monoesterification enhanced selectivity of marchantin A. ME3 was also the most active among all derivatives against lung cancer cells A549 with the slightly lower activity and selectivity in comparison to marchantin A.

Chemical and biocatalytic synthesis of seven previously undescribed marchantin A ester derivatives has been presented. Chemical synthesis afforded three peresterified bisbibenzyl products (TE1-TE3), while enzymatic method, using lipase, produced regioselective monoester derivatives (ME1-ME4). The antiproliferative activities of all prepared derivatives of marchantin A were tested on MRC-5 healthy human lung fibroblast, A549 human lung cancer, and MDA-MB-231 human breast cancer cell lines. All tested esters were less cytotoxic in comparison to marchantin A, but they also exhibited lower cytotoxicity against healthy cells. Monoesters displayed higher cytotoxic activities than the corresponding peresterified products, presumably due to the presence of free catechol group. Monohexanoyl ester ME3 displayed the same IC50 like marchantin A against MDA-MB-231 cells, but the selectivity was higher. In this way, regioselective enzymatic monoesterification enhanced selectivity of marchantin A. ME3 was also the most active among all derivatives against lung cancer cells A549 with the slightly lower activity and selectivity in comparison to marchantin A.

Table S1: Characteristics of selected anti-tetanus mAbs [35,36].

Vaccines can have heterologous effects on the immune system, i.e., effects other than triggering an immune response against the disease targeted by the vaccine. We investigated whether monoclonal antibodies (mAbs) specific for tetanus could cross-react with Chlamydia and confer heterologous protection against chlamydial infection. The capability of two tetanus-specific mAbs, namely mAb26 and mAb51, to prevent chlamydial infection has been assessed: (i) in vitro, by performing a neutralization assay using human conjunctival epithelial (HCjE) cells infected with Chlamydia trachomatis serovar B, and (ii) in vivo, by using a guinea pig model of Chlamydiacaviae-induced inclusion conjunctivitis. The mAb26 has been superior in comparison with mAb51 in the prevention of chlamydial infection in HCjE cells. The mAb26 has conferred ≈40% inhibition of the infection, compared to less than 5% inhibition in the presence of the mAb51. In vivo, mAb26 significantly diminished ocular pathology intensity in guinea pigs infected with C. caviae compared to either the mAb51-treated or sham-treated guinea pigs. Our data provide insights that tetanus immunization generates antibodies which induce heterologous chlamydial immunity and promote protection beyond the intended target pathogen.

Pseudomonas aeruginosa is a leading cause of nosocomial infections that are becoming increasingly difficult to treat due to the occurrence of antibiotic resistant strains. Since P. aeruginosa virulence is controlled through quorum sensing, small molecule treatments inhibiting quorum sensing signaling pathways provide a promising therapeutic option. Consequently, we synthesized a series of N-octaneamino-4-aminoquinoline derivatives to optimize this chemotype’s antivirulence activity against P. aeruginosa via inhibition of pyocyanin production. The most potent derivative, which possesses a benzofuran substituent, provided effective inhibition of pyocyanin production (IC50 = 12 μM), biofilm formation (BFIC50 = 50 μM), and motility. Experimentally, the compound’s activity is achieved through competitive inhibition of PqsR, and structure–activity data were rationalized using molecular docking studies.

Sintetisan je i okarakterisan katalizator magnetnih osobina na bazi paladijuma (Pd/Fe2O3) kao i katalizator na bazi paladijuma gde je kao nosač upotrebljena bakterijska nanoceluloza (Pd/BNC) i ispitana je njihova primena u reakciji dekarbonilovanja aldehida. Optimizovani reakcioni uslovi primenjeni su na aromatičnim i heteroaromatičnim aldehidima i na alifatičnim aldehidima koji imaju vodonikove atome na α- i δ-ugljenikovim atomima. Istovremeno, određen je mehanizam reakcije dekarbonilovanja i ispitana je mogućnost reciklovanja katalizatora.Pored reakcije dekarbonilovanja sintetisani katalizator Pd/Fe2O3 upotrebljen je i u reakciji reduktivnog dehalogenovanja arilhalogenida.U nastavku istražena je i reakcije dekarbonilativnog bromovanja 5-ariltiofen-2-karbaldehida. Eksperimentalnim i računarskim metodama ispitan je mehanizam reakcije kao i njena primena u sintezi triarilsupstituisanih tiofena., Palladium-based catalysts obtained by palladium immobilization on maghemite (Pd/ γ-Fe2O3) and bacterial nanocellulose (Pd/BNC) as solid supports were synthesized and characterized and their application in the decarbonylation reaction was investigated. Optimized reaction conditions were applied to a series of aromatic and heteroaromatic aldehydes as well as to several aldehydes having alpha and beta hydrogen atoms. The mechanism of the mentioned transformation as well as the possibility of catalyst recycling has also been investigated.In addition to the decarbonylation reaction, the synthesized catalyst Pd/γ-Fe2O3 was used in the reductive dehalogenation reaction of arylhalides.The decarbonylative bromination reaction of 5-arylthiophene-2-carbaldehydes was also investigated. By combining experimental and computational methods, the mechanism of this reaction was examined, as well as its application to the synthesis of triaryl-substituted thiophene derivatives.