Etiological factors involved in myelodysplastic syndrome (MDS) include immunologic, oxidative stress, and inflammatory factors, among others, and these are targets for microRNAs (miRNs). Here, we evaluated whether some miRNs may affect the tumor development comparing untreated and 5-azacitidine (5-AZA) MDS-treated patients. Peripheral blood samples were collected from 20 controls and 24 MDS patients, and selected miRNs related to redox balance and inflammation, including miR-18a, miR-21, miR-34a and miR-146a, were isolated and measured by quantitative real-time polymerase chain reaction (qRTPCR). A differential expression profile of miRNs was detected in untreated MDS patients and 5-AZA group. MiR-18a, miR-21, miR-34a and miR-146a were significantly overexpressed in untreated MDS, compared to controls. However, we did not observe any miRNs profile alteration during the progression of the disease. On the other hand, 5-AZA treatment tends to restore miRNs expression levels. Relating to prognostic risk factors, high risk MDS groups (high IPSS-R, high cytogenetic risk, high molecular risk (HMR) mutations tended to be related with higher expression levels of miR-18a and miR-34a. Higher miRNs expression is correlated with lower glutathione peroxidase activity, while they are related with a higher profile of pro-inflammatory cytokines (IL-2, IL-6, IL-8, TNF-α). Although our study was limited by the low number of MDS patients included, we identified miRNs deregulation involved in the MDS development, that could regulate redox sensors and inflammatory responses. Finally, 5-AZA treatment is related with lower miRNs expression levels in MDS patients.

With the aim to develop novel scaffolds for sustained release of drugs, we initially developed an easy approach for the synthesis of α,ω-homobifunctional mercaptoacyl poly(alkyl oxide)s. This was based on the esterification of the terminal hydroxyl groups of poly(alkyl oxide)s with suitably S-4-methoxytrityl (Mmt) protected mercapto acids, followed by removal of the acid labile S-Mmt group. This method allowed the efficient synthesis of the title compounds in high yield and purity, which were further used in the development a thioether cross-linked liposome scaffold, by thia-Michael reaction of the terminal thiol groups with preformed nano-sized liposomes bearing maleimide groups on their surface. The reaction process was followed by 1H-NMR, using a Carr-Purcell-Meiboom-Gill (CPMG) relaxation dispersion NMR experiment (1H-NMR CPMG), which allowed real-time monitoring and optimization of the reaction process. The thioether cross-linked liposomal scaffold that was synthesized was proven to preserve the nanosized characteristics of the initial liposomes and allowed sustained release of calcein (which was used as a chromophore), providing evidence for the efficient synthesis of a novel drug release scaffold consisted of nanoliposome building blocks.

The reaction of arylidene-α-amino esters with electrophilic alkenes to yield the Michael type addition compounds is optimized using several phosphines as organocatalysts. The transformation is very complicated due to the generation of several final compounds, including those derived from the 1,3-dipolar cycloadditions. For this reason, the selection of the reaction conditions is a very complex task and the slow addition of the acrylic system is very important to complete the reaction. The study of the variation of the structural components of the starting imino ester is performed as well as the expansion of other electron-poor alkenes. The crude products have a purity higher than 90% in most cases without any purification. A plausible mechanism is detailed based on the bibliography and the experimental results. The synthesis of pyroglutamate entities, after reduction of the imino group and cyclization, is performed in high yields. In addition, the hydrolysis of the imino group, under acidic media, represents a direct access to glutamate surrogates.

New [1,2]dithiolo[3,4-b]pyridine-5-carboxamides were synthesized through the reaction of dithiomalondianilide (N,N'-diphenyldithiomalondiamide) with 3-aryl-2-cyanoacrylamides or by a three-component reaction involving aromatic aldehydes, cyanoacetamide and dithiomalon- dianilide in the presence of morpholine. The structure of 6-amino-4-(2,4-dichlorophenyl)- 7-phenyl-3-(phenylimino)-4,7-dihydro-3H-[1,2]dithiolo[3,4-b]pyridine-5-carboxamide was con-firmed using X-ray crystallography. To understand the reaction mechanism in detail, density functional theory (DFT) calculations were performed with a Grimme B97-3c composite computa-tional scheme. The results revealed that the rate limiting step is a cyclization process leading to the closure of 1,4-dihydropyridine ring with an activation barrier of 28.8 kcal/mol. Some of dithiolo[3,4-b]pyridines exhibited moderate herbicide safening effects against 2,4-D . Additional-ly, ADMET parameters were calculated and molecular docking studies were performed to identify potential protein targets.

An efficient stereoselective three-component reaction for the synthesis of spiro[4H-chromene-3,3’-oxindole] derivatives was realized through an organocatalyzed cascade Knoevenagel/Michael/cyclization reaction using a quinidine-derived squaramide as the catalyst. Under the optimized conditions, the reactions of isatins, malononitrile, and sesamol yield the desired spirooxindoles in good yields (75–87%) and moderate to high ee values (up to 90% ee). Two pairs of selected enantiomers were subjected to evaluate their antiproliferative activities on three types of human cancer cell lines using the MTT assay. The results indicated that stereoselectivity and electrical effect showed significant impact on activity. Enanotiomer R-3f exhibited optimal cytotoxic activity against U2OS cell line, which was close to the inhibitory activity of positive control, Adriamycin.

At the entrance of some churches in Tuscany (Italy), the reproduction of an apparently undecipherable inscription can be found. At least from the 18^th century, this epigraphic puzzle has originated a debate on its interpretation. This study proposes a hypothesis based on the Latin alphabet used in texts contemporary to the churches where the inscription is reproduced and a possible interpretation of the message consistent with the official religious doctrine. The proposed deciphering is extended to the full text, including some signs that were previously considered as geometric forms or a specific elaboration of letters not attested in other contemporary documents.

Starting from acid chlorides, alkynes, tryptamines, and acroyl chloride, 21 densely substituted tetrahydro-beta-carbolines are prepared in a four-component one-pot reaction. In this study, the aza-Michael addition step to generate intermediate enaminones is optimized in the presence of ytterbium triflate. Moreover, apart from acroyl chloride, all reactants can be deployed in almost equimolar ratios, which increases the atom economy of the sequence. For mechanistic rationali-zation, the concluding aza-anellation was investigated by DFT calculations on potential inter-mediates and corresponding activation energies, revealing that the aza-anellation rather pro-ceeds via ene-reaction than via electrocyclization.

The near-infrared (NIR) organic dyes with strong ultrafast nonlinear optical (NLO) activities are of importance for various applications. However, such kinds of dyes are still scarce. In this work, we have compared the NLO properties of two NIR Aza-BODIPY derivatives, in which the strong electron-donating groups, namely 4-(N, N-dimethylamino) phenyl and 1-ethyl-1,2,3,4-tetrahydroquinoline groups, are connected with the cores of Aza-BODIPY. Z-Scan experimental results show that two Aza-BODIPY derivatives exhibit strong saturation absorption and large modulation depth under the excitation of femtosecond pulses at 800 nm. Under 1300 nm excitation, two derivatives exhibit strong nonlinear refraction. In addition, the Aza-BODIPY derivatives also display effective two-photon excited fluorescence emission in the wavelength range of 1200-1600 nm. Based on the experimental results, it is found that 1-ethyl-1,2,3,4-tetrahydroquinoline group can more effectively enhance the NLO properties of Aza-BODIPY derivatives compared with the 4-(N, N-dimethylamino) phenyl group, thus providing new possibilities for the design and development of NIR NLO materials.

Non-enzymatic thiol addition into α,ß-unsaturated carbonyl system is associated with several biological effects. In vivo, the reactions can form small-molecule thiol (e.g., glutathione) or protein thiol adducts. The reaction of two synthetic (4’-methyl- and 4’-methoxy substituted) cyclic chalcone analogs with glutathione and N-acetylcysteine was studied by HPLC-UV method. The selected compounds displayed in vitro cancer cell cytotoxicity (IC50) of different orders of magnitude. The structure of the formed adducts was confirmed by HPLC-MS. The incubations were performed under three different pH conditions (pH 3.5/3.8, 6.3/6.7, and 8.0/7.4). The chalcones intrinsically reacted with both thiols under all incubation conditions. The initial rates and compositions of the final mixtures depended on the substitution and the pH. The frontier molecular orbitals and the Fukui function were carried out to investigate the effects on open-chain and seven-membered cyclic analogs. Furthermore, machine learning protocols were used to provide more insights into physicochemical properties and to support the different thiol-reactivity. HPLC analysis indicated diastereoselectivity of the reactions. The observed reactivities do not directly relate to the different in vitro cancer cell cytotoxicity of the compounds.

Curcumin and trans-cinnamaldehyde are acrolein-based Michael acceptor compounds that are commonly found in domestic condiments, and known to cause cancer cell death via redox mechanisms. Based on the structural features of these compounds we designed and synthesized several 2-cinnamamido-N-substituted-cinnamamide (bis-cinnamamide) compounds. One of the derivatives, (Z)-2-[(E)-cinnamamido]-3-phenyl-N-propylacrylamide 1512 showed a moderate antiproliferative potency (HCT-116 cell line inhibition of 32.0 µM), good selectivity profile (no inhibition of normal cell lines), and proven cellular activities leading to apoptosis. SAR studies led to more than 10-fold increase in activity. Our most promising compound, [(Z)-3-(1H-indol-3-yl)-N-propyl-2-[(E)-3-(thien-2-yl)propenamido)propenamide] 4112 killed colon cancer cells at IC50 = 0.89 µM (Caco-2), 2.85 µM (HCT-116) and 1.65 µM (HT-29), while exhibiting much weaker potency on C-166 and BHK normal cell lines (IC50 = 71 µM and 77.6 µM, respectively). Cellular studies towards identifying the compounds mechanism of cytotoxic activities revealed that apoptotic induction occurs in part as a result of oxidative stress. Importantly, the compounds showed inhibition of cancer stem cells that are critical for maintaining the potential for self-renewal and stemness. The results presented here show discovery of covalently-acting Michael addition compounds that potently kill cancer cells by a defined mechanism, with minimal effect on normal noncancerous cell.

In light of climate changes, technological development and the use of renewable energy sources are considered very important nowadays, both in newly-designed structures and reconstructed historic building, resulting in the reduction of the commercial energy consumption and CO2 environmental emissions. This paper explores the possibilities of improving the energy efficiency of heritage sacred buildings by utilizing photovoltaic systems. As an exceptionally significant cultural good, the Cathedral of St. Michael the Archangel in Belgrade shall serve as a case study, with the aim of examining the methods of mounting photovoltaic (PV) panels, by taking into account the fact that the authenticity and the aesthetic value of this cultural monument must remain intact. A comparative analysis of the two options for installing PV panels on the southwestern roof of the church was performed using simulations in PVgis and PVsist V6.84 software, with the aim of establishing the most efficient option in terms of power generation. The simulation results show that photovoltaic panels can produce 151650 kWh (Option 1) and 150894 kWh (Option 2) per year, while the required amount of energy is 42726.77 kWh. The electricity produced exceeds the electricity requirements for the decorative lighting of the Cathedral Church, so it can be used for other purposes in the sacral complex.

In light of climate changes, technological development and the use of renewable energy sources are considered very important nowadays, both in newly-designed structures and reconstructed historic building, resulting in the reduction of the commercial energy consumption and CO₂ environmental emissions. This paper explores the possibilities of improving the energy efficiency of heritage sacred buildings by utilizing photovoltaic systems. As an exceptionally significant cultural good, the Cathedral of St. Michael the Archangel in Belgrade shall serve as a case study, with the aim of examining the methods of mounting photovoltaic (PV) panels, by taking into account the fact that the authenticity and the aesthetic value of this cultural monument must remain intact. A comparative analysis of the two options for installing PV panels on the southwestern roof of the church was performed using simulations in PVgis and PVsist V6.84 software, with the aim of establishing the most efficient option in terms of power generation. The simulation results show that photovoltaic panels can produce 151650 kWh (Option 1) and 150894 kWh (Option 2) per year, while the required amount of energy is 42726.77 kWh. The electricity produced exceeds the electricity requirements for the decorative lighting of the Cathedral Church, so it can be used for other purposes in the sacral complex.

A Multicomponent Reaction (MCR) strategy, alternative to the known cycloaddition reaction, towards variously substituted 1-amino-1H-imidazole-2(3H)-thione derivatives has been successfully developed. The novel approach involves α-halohydrazones whose azidation process followed by tandem Staudinger/aza-Wittig reaction with CS₂ in a sequential MCR regioselectively leads to the target compounds avoiding the formation of the regioisomer iminothiazoline heterocycle. The approach can be applied to a range of differently substituted α-halohydrazones bearing also electron-withdrawing groups confirming the wide scope and the substituent tolerance of the process for the synthesis of the target compounds. Interestingly, the concurrent presence of reactive functionalities in the scaffolds so obtained, ensures postmodifications in view of N-bridgedheaded heterobicyclic structures.

DNA methylation is one of the epigenetic mechanisms which have been implicated in cellular differentiation, ageing and disease development. The effect of hypomethylating drug 5-aza-2´deoxycytidine (5-aza dC) on the biosynthetic profile of caudal region chondrocytes from chick sternum was studied in detail. The chondrocytes in culture were treated with varying doses of 5-aza dC for 48h and maintained subsequently without the treatment and harvested at selected time points for analysis of growth and differentiation status. 15µg/ml of 5-aza dC showed optimum Concentration at which there was a significant increase in DNA synthesis and RNA synthesis as per cell basis. There was also a significant increase in total protein synthesis and collagen synthesis as per cell basis at this concentration. This optimal concentration also showed to up regulate the gene expression of Type X collagen and alkaline phosphatase, which are the marker of hypertrophic chondrocyte expression. These results further support the notion that methylation is the major epigenetic factor controlling the differentiation and maturation of chondrocytes.