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Theoretical methods for the rational selection of coformers to form drug co-crystals
No full textKada je riječ o farmaceutskoj industriji, posljednjih nekoliko godina se kokristalima pridaje sve veća pažnja. Riječ je o višekomponentnim supramolekularnim oblicima koji se sastoje od nenabijene aktivne farmaceutske tvari i koformera, koji mogu biti povezani vodikovom vezom, halogenom vezom, Londonovom silom i dr. Glavna svrha proučavanja i priprave kokristala je poboljšanje fizikalno - kemijskih svojstava kao što su topljivost, stabilnost, brzina otapanja i higroskopnost, ali bez kovalentne modifikacije lijeka. Jedna od ključnih koraka u stvaranju kokristala je odabir koformera. Kako bi se olakšalo stvaranje farmaceutskog kokristala postoje teoretske metode koje olakšavaju odabir koformera, a to su: COSMO - RS, MEPS, usporedba energije kristalne rešetke, Hirshfeldova površinska analiza, Hansenov parametar topljivosti i pKa. Upravo će u ovom radu biti riječ o teoretskim metodama za racionalan odabir tvari za sintezu farmaceutskog kokristala.When it comes to the pharmaceutical industry, great attention has been paid to co-crystals in recent years. These are multicomponent supramolecular forms consisting of an uncharged active pharmaceutical substance and coformers, which can be connected by a hydrogen bond, halogen bond, London force, etc. The main purpose of studying co-crystals is to improve physicochemical properties such as solubility, stability, dissolution rate and hygroscopicity, but without a covalent drug modification. One of the most complicated steps in creating a co-crystal is choosing a coformer. In order to facilitate the formation of a pharmaceutical co-crystal, there are theoretical methods that facilitate the selection of coformers, namely: COSMO - RS, MEPS, crystal lattice energy comparison, Hirshfeld surface analysis, Hansen solubility parameter and pKa. This paper will discuss the theoretical methods for the rational selection of substances for the synthesis of pharmaceutical co-crystals
Monitoring of selected water quality parameters of Karašica and Vučica surface water
No full textSliv Karašice i Vučice smješten je u Slavonskoj podravini koje je izloženo različitim izvorima zagađenja. Cilj ovog rada bio je analizirati kakvoću površinske vode rijeka Karašice i Vučice na temelju izmjerenih odabranih fizikalno-kemijskih parametara i važećih zakonskih regulativa i propisa. Naglasak je stavljen na zadnjih sedam godina, ali se statistička obrada odabranih parametara odnosi i na duži period. Uzorci su prikupljani najčešće u mjesečnim intervalima, na lokacijama Petrijevci i Marijančaci na Vučici, a na rijeci Karašici na lokacijama cesta Crnac Krčenik, nizvodno od Valpova i Črnkovci. Od fizikalno-kemijskih parametara promatrani su pH, biokemijska potrošnja kisika (BPK5), kemijska potrošnja kisika (KPK), spojevi dušika i fosfora. Dobiveni rezultati upućuju na lošu do vrlo dobru kakvoću vode ovisno o parametru i godini. Potrebno je nastaviti kontinuirano praćenje kakvoće površinske vode sliva Karašice i Vučice kako bi se pratilo stanje vode i primjena mjera zaštite voda od daljnjeg zagađenja. Da bi se dobio bolji uvid u stanje vode, u ispitivanje je potrebno uključiti i ostale parametre kojima se može procijeniti kakvoća vode.Karašica and Vučica catchment area is located in the Slavonian Podravina, which is exposed to various sources of pollution. Hence, the aim of this thesis was to give an overview and assessment of water quality of Karašica and Vučica River based on the analysis of selected water physico-chemical parameters according to the national regulations and laws. The main focus was on the last seven years, but statistical analysis included a longer period. Water samples were collected usualy on a monthly basis, on the Vučica River at Petrijevci and Marijančaci location, and on the Karašica River at road Crnac Krčenik, downstream from Valpovo and Črnkovci location. pH value, biochemical oxygen demand (BOD5), chemical oxygen demand (COD-Mn), nitrogen and phosphorus compounds were analyzed. The obtained results indicate bad to very good water quality depending on the observed parameter and year. Continuous monitoring of water quality is necessary in order to insure adequate implementation of measures for water quality protection. For a better insight regarding water quality, other parameters that could indicate the condition of a water body should also be included in the study
Single crystal preparative methods from solution
No full textJedinični kristal, drugog imena monokristal, kristalno je tijelo koje ima pravilnu trodimenzionalnu strukturu. Savršeni jedinični kristali su transparentni, oštrih uglova te veličine od 0,1 do 0,4 mm. Zbog svoje pravilne i neprekinute unutrašnje strukture, sadrže izvanredna svojstva poput električnih, optičkih, termičkih i mnogih drugih. U ovom radu opisane su metode priprave jediničnih kristala iz otopine poput metode polaganog hlađenja, evaporacije, difuzije otapala te difuzije para. Jedinični kristali također se mogu pripraviti metodama iz taline, Czochralski procesom i Bridgmanovom tehnikom te sublimacijskim metodama. U eksperimentalnom dijelu opisan je postupak određivanja topljivosti pojedinih spojeva alkohola u različitim otapalima i izbor metode priprave monokristala. Rendgenskom difrakcijom dobiveni su opći kristalografski podaci o pojedinom spoju te je utvrđeno da spoj Do6OH kristalizira u dva kristalna sustava. U dva različita otapala, DMF i DMSO, metodom difuzije otapala, nastali jedinični kristali kristaliziraju u rompskom i monoklinskom kristalnom sustavu. Jedinični kristali spoja Do3OH pripravljeni su metodom evaporacije iz benzena, dok su jedinični kristali spoja Do5OH pripravljeni metodom polaganog hlađenja iz benzena.Single crystal, otherwise known as a monocrystal, is a crystalline solid that has a regular three-dimensional structure. The perfect single crystals are transparent, sharp corners and with measurements from 0.1 to 0.4 mm. Due to their regular and uninterrupted internal structure, they contain outstanding properties such as electrical, optical, thermal and many others. This paper describes single crystal preparative methods from a solution such as slow-cooling method, solvent evaporation, solvent diffusion and vapour difussion. Single crystals can also be grown by melt methods, Czohralski process and Bridgman technique, and sublimation methods. The experimental part describes the procedure for determining the solubility of individual alcohol compounds in different solvents and the choice of solvent-based preparation methods. General crystallographic data of each compound were obtained by X-ray diffraction and it was found that the compound Do6OH crystallizes in two crystal systems. In two different solvents, DMF and DMSO, using the solvent diffusion method, the resulting single crystals crystallize in a orthorhombic and monoclinic crystal system. Single crystals of the compound Do3OH were prepared by the evaporation method from benzene, while the single crystals of the compound Do5OH were prepared by the method of slow cooling from benzene
Chemistry of the drugs for anxiety-depressive disorders
No full textAnksioznost i depresija glavni su psihijatrijski problemi i razlozi hospitalizacije u Hrvatskoj. Anksioznost je psihijatrijski poremećaj kojeg obično prate zabrinutost i strah. S druge strane, depresija je poremećaj raspoloženja, kojeg prate osjećaj tuge i žalosti, ali nerijetko i suicidalne misli. Ova dva poremećaja se najčešće pojavljuju zajedno jer osoba koja ima depresiju nerijetko pati i od nekog anksioznog poremećaja. Oba poremećaja su kompleksna i najčešće su poporaćena pojavom somatskih bolesti. Ovaj diplomski rad bavi se liječenjem ova dva povezana stanja. Postoji mnogo skupina lijekova na tržištu, a odabrano je pet predstavnika anksiolitika i antidepresiva. Antidepresivi koji su obrađeni su: dezipramin, selegilin, escitalopram, bupropion i tianeptin. Nadalje, anksiolitici koji su obrađeni su: alprazolam, diazepam, lorazepam, oksazepam i nitrazepam. Navedenim lijekovima su opisane strukture i svojstva, te njihov mehanizam djelovanja. Osim navednih lijekova ponuđena su i alternativna rješenja kao što je kognitivno-bihevioralna terapija. Kao alternativa mogu poslužiti i atipični antipsihotici, te kanabinoidi iz biljke cannabis sativa posebice CBD.Anxiety and depression are the main psychiatric problems and reasons for hospitalization in Croatia. Anxiety is a psychiatric disorder that is usually accompanied by anxiety and fear. Depression, on the other hand, is a mood disorder accompanied by feelings of sadness and grief, but often also suicidal thoughts. These two disorders usually occur together because a person who is depressed often suffers from an anxiety disorder. Both disorders are complex and are most often accompanied by the appearance of somatic diseases. This Diploma Thesis deals with the treatment of two related conditions. There are many groups of drugs on the market of which five that represent anxiolytics and antidepressants have been selected. Antidepressants discussed are: desipramine, selegiline, escitalopram, bupropion and tianeptine. Furthermore, anxiolytics discussed are: alprazolam, diazepam, lorazepam, oxazepam and nitrazepam. Structures, properties and the mechanisms of action have been described to the drugs named above. In addition to these drugs, alternative solutions such as cognitive-behavioral therapy have been offered. Atypical antipsychotics and cannabinoids from the cannabis plant sativa special CBD can also serve as an alternative
Phytochemical analysis by FTIR spectroscopic analysis of mistletoe (Viscum album L.)
No full textU ovome radu provedena je fitokemijska analiza svježih listova i grančica bijele imele (Viscum album L.) ubranih sa stabala na različitim lokacijama Republike Hrvatske i na komercijalno dostupnim proizvodima (čajevi). Kako bi se identificirale moguće prisutne skupine, metodom FTIR spektroskopije uzorci su analizirani su u različitim otapalima (etanol, metanol, voda ) u rasponu valnih duljina od 400 do 4000 cm-1. Rezultati FTIR spektroskopske analize ukazali su na postojanje različitih funkcionalnih skupina u ekstraktima metanola, etanola i vode. Maksimumi su u većini slučajeva bili najizraženiji u ekstraktima metanola, etanola, a potom u vodenim ekstraktima listova i grančica imele. Kako bi se odredile moguće sličnosti /razlike među uzorcima, na podatke dobivene FTIR spektroskopijom primijenjena je metoda analize glavnih komponenata (engl. Principal Component Analysis, PCA). Rezultati analize glavnih komponenata pokazali su da je na različitosti (sličnosti) među prikupljenim uzorcima najveći utjecaj imao zemljopisni položaj biljke.In this paper, phytochemical analysis of fresh leaves and twigs of white mistletoe (Viscum album L.) harvested from trees in different locations of the Republic of Croatia and on commercially available products (teas) was performed. In order to identify possible groups present, by FTIR spectroscopy, the samples were analyzed in different solvents (ethanol, methanol, water) in the wavelength range from 400 to 4000 cm-1. The results of FTIR spectroscopic analysis indicated the existence of different functional groups in the extracts of methanol, ethanol and water. The maximums were in most cases most pronounced in the extracts of methanol, ethanol, and then in the aqueous extracts of mistletoe leaves and stems. In order to determine possible similarities/differences between samples, the Principal Component Analysis (PCA) method was applied to the data obtained by FTIR spectroscopy. The results of the principal components analysis showed that geographical differences had the greatest influence on differences (similarities) among collected samples plants
Review on advanced theoretical methods for molecular structure-based calculations of molecular properties
No full textMetoda grupnih doprinosa je tehnika koja se koristi za procjenu i predviđanje termodinamičkih i brojnih drugih svojstava tvari, među kojima su i Hansenovi parametri topljivosti, iz molekulske strukture. Za predviđanje Hansenovih parametara topljivosti čistih organskih spojeva se upotrebljavaju dvije vrste tipičnih skupina koje obuhvaćaju: skupinu prvog reda koja opisuje osnovnu molekularnu strukturu spojeva i skupina drugog reda, koja se temelji na teoriji konjugacije i poboljšava točnost predviđanja. Raznovrsnost tipičnih skupina osigurava predviđanje Hansenovih parametara topljivosti za veliki broj organskih spojeva, obuhvaćajući složene više prstenaste, heterocikličke i aromatske strukture. U metodi nisu potrebni nikakvi eksperimentalni podaci jer se predviđanja temelje isključivo na molekularnoj strukturi spojeva, a izračunate predviđene vrijednosti omogućuju izrazito pouzdan odabir otapala. Posebno koncipirani algoritmi dopuštaju izradu popisa novih molekularnih struktura koje bi, ako se sintetiziraju, mogle biti idealno prikladna otapala za niz odgovarajućih primjena poput proizvodnje kemikalija, lijekova, različitih premaza, hrane i kozmetike.The group contribution method is a method to estimate thermodynamic and more of other substance properties, among which are Hansen's solubility parameters, from molecular structure. To estimate Hansen solubility parameters of pure organic compounds, two types of specific groups comprising are used: a first-order group describing the basic molecular structure of compounds and a second-order group based on conjugation theory and improving prediction accuracy. The diversity of specific groups ensures the prediction of Hansen solubility parameters for many organic compounds, encompassing complex multiring, heterocyclic, and aromatic structures. No experimental data are required in the method because the predictions are based solely on the molecular structure of the compounds, and the calculated predicted values allow for highly reliable solvent selection. Futhermore, specially designed algorithms allow the creation of a list of new molecular structures that, if synthesized, could be ideally suited solvents for a range of suitable applications such as the production of chemicals, drugs, various coatings, food and cosmetics
Crystal structures of noble gas compounds
No full textProcesom kristalizacije nastaju krutine zvane kristalima koje su građene od atoma ili molekula periodično ponavljanih u prostoru. Razlikujemo ionske, molekulske, metalne i kovalentne kristale koji se razlikuju prema vrsti čestica koje ih grade te vrsti veza između njih. Svrstavaju se u prostorne i točkaste grupe, Bravaisove rešetke te osnovne kristalne sustave. U 18. skupini periodnog sustava elemenata smješteni su plemeniti plinovi, helij, neon, argon, kripton, ksenon i na kraju radon. Plemeniti plinovi su plinovi bez boje, mirisa i okusa te u pravilu ne stvaraju spojeve s drugim elementima, odnosno inertni su. Industrijski se dobivaju na način na koji su i prvi put dobiveni, frakcijskom destilacijom tekućeg zraka. Neil Bartlett, kanadski kemičar, je prvi proučavao njihovo svojstvo inertnosti i otkrio prve spojeve plemenitih plinova, fluoride. Helij u uvjetima visokog tlaka ulazi u strukturu spoja 4-hidroksi cijanobenzena koji pod tlakom rotira u prostoru čime se stvaraju nove interakcije pogodne za ulazak helija. Nadalje, svi plemeniti plinovi mogu pri određenim uvjetima ući u strukture nešto kompleksnijih spojeva. Bilo da se radi o istraživanju iz znatiželje ili radi općeg dobra, kao što je to slučaj kod ksenona, rezultati su nadasve zanimljivi. U svrhu zarobljavanja plinova najviše se koriste tzv. MOF-ovi, tj. metaloorganske mreže.The crystallization proces produces solids, crystals, which are made of atoms and molecules periodically repeated in space. There are ionic, covalent, metal and molecular crystals and the difference between them is in the type of particles of which they are made and in the type of bonds. We can classify them into space groups, crystallographic point groups, Bravais lattices and finally into main crystal systems. In the 18th group of the Periodic Tablet of Elements are noble gases, helium, neon, argon, krypton, xenon and radon. Noble gases are colorless, tasteless, with no smell and in general, they do not make compounds with other elements, so basically they are inactive. In industry, noble gases are obtained by fractional distillation of liquid air, just in the way they were first isolated. Canadian, Neil Bartlett, was the first scientist who studied the inactivity of noble gases and the first who discovered noble gas compounds, fluorides. Under high pressure conditions, helium can enter into the structure of compound 4-hydroxy cyanobenzene, which rotates under the pressure and creates new interactions and the entrance for helium is allowed. Today, it is known that noble gases can fit into complex compounds. Whether it is research out of curiosity or for the common good, as is the case with xenon, the results are interesting. For the purpose of capturing noble gases, the most used are MOFs or metal organic frameworks
Analysis of selected physicochemical parameters of surface water quality on the example of small water bodies
No full textKakvoća površinske vode može se utvrditi analizom odgovarajućih parametara kakvoće vode koji su definirani putem zakona, normi i regulativa. U ove se parametre ubrajaju i fizikalno-kemijski parametri koji obuhvaćaju pH. biokemijsku potrošnju kisika, kemijsku potrošnju kisika i nutrijente, čije su granične vrijednosti za pojedino stanje vodnog tijela definirani zakonom. U radu je dana procjena kakvoće površinske vode za manja vodna tijela - Baranjsku Karašicu, Gabošku Vučicu i Trnave (dva vodna tijela: Trnava Murska i vodotok Trnava kod Visoke Grede). Uzorci su prikupljani mjesečno u periodu od 6 godina (2013.-2018.), na 5 lokacija. Ocjene ekološkog stanja ovih vodnih tijela je za Baranjsku Karašicu i Gabošku Vučicu - umjereno, Trnava (Visoka Greda) - vrlo loše, Trnava (most na cesti Čakovec - Goričan) - loše, Trnava (uzvodno od Lateralnog kanala) - dobro. Kako bi se dobila potpunija slika stanja ovih vodnih tijela, potrebno je uzeti u obzir i druge parametre kakvoće vode. Neovisno o tome. monitoring stanja ovih vodnih tijela je potrebno nastaviti, kako bi se pratilo daljnje stanje površinske vode i pravovremeno uočilo pogoršanje kakvoće površinske vode.Surface water quality can be determined by analysing adequate water quality parameters defined by laws, norms and regulations. These parameters include physicochemical parameters, such as pH, biochemical oxygen demand, chemical oxygen demand and nutrients, limit values which are legally defined. In this thesis, assessment of small water bodies surface water quality is given on the example of Baranjska Karašica, Gaboška Vučica an Trnava (two water bodies: Trnava Murska and Trnava at Visoka Greda). Samples were collected on a monthly basis, time frame of 6 years (2013-2018), at 5 locations. Ecological condition of these water bodies is as follows: Baranjska Karašica and Gaboška Vučica - moderate, Trnava (Visoka Greda) - very bad, Trnava (bridge at road Čakovec - Goričan) - bad, Trnava (upstream from Lateral canal) - good. In order to get a more complete idea of these water bodies water quality, other parameters of water quality should also be considered. Regardless, continual monitoring of water quality is essential in order to keep track of water body condition and notice quality deterioration in a timely manner
Crystal structure solution and refinement of compounds with included gases
No full textMakrociklička Schiffova baza N4O4 (1,6,20,25-tetraaza2,5: 8,9: 17,18: 21,24: 27,28: 36,37-heksabenzo-10,16,29,35-tetraoksa-ciklooktatriakonta-1,6,20,25-tetraen)(1) pripravljena je reakcijom [2 + 2] ciklokondenzacije odgovarajućeg dialdehida i diamina. Kristalna i molekulska struktura određena je rendgenskom difrakcijom na monokristalnom uzorku spoja. Predmet ovog rada je rješavanje i utočnjavanje kristalnih struktura 5 zadanih makrocikličkih spojeva (1xCO2, 1xNH3, 1xCl2, 1xSO2, 1xH2S) pripravljenih izlaganjem kloroformskog solvata (1xCLF) parama CO2, NH3, Cl2, SO2, i H2S. Za utočnjavanje i rješavanje kristalnih struktura korišteni su programi Olex2 i Mercury. Spojevima je određena struktura i kristalografski parametri.Macrocyclic Schiff base N4O4 (1,6,20,25-tetraaza2,5: 8,9: 17,18: 21,24: 27,28: 36,37-hexabenzo-10,16,29,35-tetraoxa-cyclooctatriaconta -1,6,20,25-tetraene) (1) was prepared by the [2 + 2] cyclocondensation reaction of the corresponding dialdehyde and diamine. The crystal and molecular structure was determined by X-ray diffraction on a single crystal sample of the compound. The subject of this paper is solving and refining the crystal structures of 5 given macrocyclic compounds (1xCO2, 1xNH3, 1xCl2, 1xSO2, 1xH2S) prepared by exposing chloroform solvate (1xCLF) to CO2, NH3, Cl2, SO2, and H2S vapors. Olex2 and Mercury programs were used to refine and resolve crystal structures. The structure and crystallographic parameters were determined by the compounds
Synthesis and characterization of Schiff bases derived from aminobenzoic acids and aromatic aldehydes
No full textSupstituirani imini poznatiji su pod nazivom Schiffova baza. Njihova glavna strukturna karakteristika je posjedovanje imino skupine (C=N), a dušični su analozi aldehida i ketona (imino skupina umjesto karbonilne). Nastaju u reakcijama kondenzacije aldehida/ketona s primarnim aminima uz gubitak molekule vode. Reakcija je izrazito osjetljiva na pH, a kao optimalna vrijednost uzima se 4,5. Iznimno su zanimljive zbog svojih raznovrsnih kemijskih svojstava koja im omogućuju primjenu u industriji i medicini. Najvažnija karakteristika je mogućnost stvaranja kompleksnih spojeva s brojnim metalima što uvelike doprinosi raznolikosti fizikalnih i kemijskih svojstava. U literaturnom pregledu navedena su neka od najvažnijih fizikalnih i kemijskih svojstava polaznih reaktanata: salicilaldehida, 3-aminobenzojeve kiseline i 4-aminobenzojeve kiseline. Također je pojašnjen i sam princip rada analitičke metode kojom je potvrđen rezultat: FT-IR spektroskopija. Sinteza u ovom radu uključuje ručno usitnjavanje 3-aminobenzojeve kiseline, njenu reakciju sa salicilaldehidom te proces kristalizacije pri sobnoj temperaturi. Nakon kristalizacije uzorak je filtriran i pripremljen za daljnju analizu. Jednak postupak ponovljen je i sa 4-aminobenzojevom kiselinom. Dobiveni produkti analizirani su FT-IR spektroskopijom nakon čega su dobiveni spektri uspoređeni s polazišnim kemikalijama čime je potvrđena uspješnost sinteza.Substituted imines are better known as Schiff base. Their main structural characteristic is the possession of an imino group (C = N) and are nitrogen analogues of an aldehyde or ketone (imine group substitutes carbonyl group). They are formed in the condensation reactions of aldehydes / ketones with primary amines with the loss of water molecules. They are extremely interesting because of their diverse chemical properties that allow them to be used in industry and medicine. The most important feature is the ability to form complex compounds with numerous metals which greatly contributes to the diversity of physical and chemical properties.The literature review lists some of the most important physical and chemical properties of the starting reactants: salicylaldehyde, 3-aminobenzoic acid, and 4-aminobenzoic acid. The principle of operation of the analytical method which confirmed the result was also clarified: FT-IR spectroscopy. The synthesis in this paper involves the manual comminution of 3-aminobenzoic acid, its reaction with salicylaldehyde, and the crystallization process at room temperature. After crystallization, the sample was filtered and prepared for further analysis. The same procedure was repeated with 4-aminobenzoic acid. The obtained products were analyzed by FT-IR spectroscopy, after which the obtained spectra were compared with the starting chemicals, which confirmed the success of the synthesis