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The aim of this report is to present the electrospray ionization mass spectrometry results of the non-covalent interaction of two biologically active ligands, N-1-(p-toluenesulfonyl)cytosine, 1-TsC, 1 and N-1 methanesulfonylcytosine, 1-MsC, 2 and their Cu(II) complexes Cu(1-TsCN3)2Cl2, 3 and Cu(1-MsC-N3)2Cl2 and 4 with biologically important cations: Na+, K+, Ca2+, Mg2+ and Zn2+. The formation of various complex metal ions was observed. The alkali metals Na+ and K+ formed clusters because of electrostatic interactions. Ca2+ andMg2+ salts produced the tris ligand andmixed ligand complexes. The interaction of Zn2+ with 1–4 produced monometal and dimetal Zn2+ complexes as a result of the affinity of Zn2+ ions toward both O and N atoms.

The aim of this report is to present the ESI MS results of the non-covalent interaction of sulfonamide derivatives of cytosine nucleobase (very good antitumor agent - the inhibitory effect on enzymes that play an important role in the metabolism of tumor cells) with biologically important metal cations since the cells growing media consists of a significant amount of dissolved different salts. Although all components of the media are prone to interact with the agent, the metal ions (Na+, K+, Ca2+, Mg2+, Zn2+, Fe2+) were in focus in this study. Two ligands N-1-(p-toulenesulfonyl)cytosine, 1-TsC, and N-1-(methanesulfonyl)cytosine, 1-MsC, as well as their copper (II) complexes: mononuclear complex Cu(1-TsC-N3)2Cl2, containing 1-TsC, as ligand and Cu(1-MsC-N3)2Cl2 containing 1-MsC, as ligand were studied. The study elaborated the stability of ligands, and copper complexes in solutions (DMSO/MeOH or H2O or ACN and DMF/ MeOH or H2O or ACN) and possible non-covalent interaction. In cases in which comparisons can be made, the gas-phase results show unexpectedly strong analogies to those observed in the condensed phase. For example the interaction of Zn2+ with ligands, or copper complexes produced a variety of complex ions as a result of its affinity towards both O and N as ligands. We observed the formation of monometal Zn2+ complexes (e.g. signal observed at m/z 858 assigned as [(1-TsC)3(-H)Zn]+) and mixed ligand dimetal complexes that included water molecules in the structures of complexes (e.g. signal observed at m/z 894 assigned as [(1-TsC)3(-H)Zn(H2O)2]2 2+). The interferences of Zn2+ ions with copper complexes were observed. Therefore, the interferences of potential drug and metal ions could be predicted before pursuing the biological studies.

Determination of fatty acids is of major interest in metabolomics due to their extensive role in metabolic pathways. Recently it has been shown that the fatty acid chain length plays important role in the skin barrier function and some diseases as atopic dermatitis. We have developed RP HPLC-ESI-MS method allowing the separation and quantification of free fatty acids (FFA) derivatives including very long fatty acids (>22 carbons). Fatty acids esters, obtained by derivatization of FFA with 2-bromo-1-methylpyridinium iodide and 3-carbinol-1-methylpyridinium iodide have been separated on C4 column. For the elution different alcohols (methanol, ethanol and isopropanol) and formic acid in acetonitrile have been examined. Formic acid and methanol showed the highest signal response and improved peak shape in particular for very long chain fatty acids. The method was successfully applied for the determination of saturated and unsaturated FFA in human stratum corneum obtained by tape stripping technique.

We report about the selective reduction of eight cyclohexanones with NaBH4 in aqueous solutions of  -cyclodextrin, PEG-400, cationic micelles of CTAB and CPC, anionic micelles of SDS and SS at room temperature and at 80 ˚ C. All results were compared with NMR, GC-MS as well as with IR. The charge of the micellar head group influences the preferential direction of hydride attack by favoring one reactant conformation over the other and the outcome is more products with the H- in the axial position. One example is the reduction of 4: in CTAB: 73% of trans 4-tert-butylcyclohexanol was obtained while in SDS 90% or SS 94%. The importance of this work is in the obtained selectivity, the high yields, and the simplicity.

Kompleksi Fe(II) s miješanim ligandima (2 i 3) nastaju jednostavnim miješanjem liganada 1, 10- fenantrolina i 1, 10-fenantrolin-5, 6-diona te FeSO4 × 7 H2O u vodi na sobnoj temperaturi, ali dobivaju se u smjesi kompleksa 1-4. Kompleksi se vrlo brzo pregrađuju izmjenjujući ligande i nije ih moguće odvojiti klasičnim kromatograskim metodama jer se ireverzibilno vežu na standardne krute nosače kao što su silika-gel i alumina. Do sada je jedino Mudasir opisao razdvajanje sličnih kompleksa upotrebom ion-par reverzne fazne kromatografije RP IPC. I mi smo uspjeli razdvojiti komplekse s visokom selektivnošću koristeći 0, 001 M vodenu otopinu KPF6. Mi smo uspjeli razviti novu metodu odvajanja kompleksa koristeći metanol i vodu kao mobilne faze prema dolje prikazanom gradijentu i to uz upotrebu Develosil RP- Aqueous [C30] 5µm, 150 × 4, 6 mm kolone koja je stabilna i u 100 % vodenim uvjetima. Protok je bio podešen na 0, 5 mL/min od 0 do 7 minute te od 8 do 20 minute na 0, 6 mL/min. Detekcija je praćena na 4 valne duljine: 254, 354, 480 i 510 nm. Prednost te metode je da se uparavanjem mobilne faze dobivaju čisti produkti, nema potrebe za uklanjanjem soli.

Heckova reakcija može se najopćenitije definirati kao paladijem(0) katalizirano unakrsno sprezanje ugljik-ugljik između vinilnih ili arilnih halogenida ili sulfonata s alkenom u baznim uvjetima. Prava ekspanzija proučavanja i primjene ove reakcije nastala je u posljednjih 15-ak godina. Heckova reakcija primjenjuje se danas za pripravu jednostavnih ugljikovodika, premoštenih prstenastih struktura, spiro-spojeva, tetrasupstituiranih ugljikovih centara, polimera, pa sve do elegantnih kaskadnih enantioselektivnih sinteza prirodnih spojeva. Svrha ovog kraćeg pregleda je prikazati osnove mehanizma Heckove reakcije, opisati različite i pomalo misteriozne kompozicije upotrebljivih katalizatora te ukazati na trenutačno stanje i primjenu ovog reakcijskog principa., The Heck reaction is defined as a Pd(0)-mediated coupling of an aryl or vinyl halide or sulfonate with an alkene under basic conditions. The real push to study and utilize this powerful tool for C-C cross coupling reactions started about 15 years ago. The application of the Heck reaction ranges from the preparation of simple hydrocarbons, bridged cyclic structures, spiro-compounds, tetra-substituted carbon centers, novel polymers, to new advanced enantioselective synthesis of natural products. The aim of this mini review is to summarize the current state of understanding of the basics of the Heck reaction mechanism, describe various and sometimes mysterious compositions of applicable catalyst, as well as to review the important recent developments and applications of this principle.

Fluorescence excitation spectra and single-vibronic-level emmission spectra of the model chromophores cyclopentaphenanthrene and 1, 8-dimethyl-naphtalene and the bichromphores spiro-fluorene-phenanthrene and spiro-fluorene-naphtalene are presented and analyzed.

Very large time-dependent spectral blue shifts (up to over 7400 cm(-1)) induced by ion pairing were observed for long-lived photoinduced charge-separated states of two probe molecules: 4-amino-4'-nitrobiphenyl (p-ANBP) and 4-amino-4'-nitroterphenyl (p-ANTP). These shifts are analogous to the well-known time-dependent fluorescence shifts (TDFS) of transient CT states, which are attributed to nonequilibrium dipolar solvation in polar media as well as to ionic atmosphere relaxation in solutions of electrolytes. It is demonstrated that the dynamic spectral shifts of transient CT absorption bands can be utilized as sensitive probes of ion-pairing processes and that they offer significant advantages over the traditional fluorescent probes. The long lifetime of charge-separated excited triplet states (e.g., >3 mu s for p-ANTP) allows time-resolved study of electrolyte dynamics in highly dilute solutions (100 mM salt) and limit the approach to highly polar solvents.

The synthesis of 4, 5-diazospirobifluorene and 4, 5-diazobifluorenylidene, the first two members of a new family of transition metal ligands designed for the study of intramolecular electron and excitation transfer is reported. The description of the synthesis and the H-1-NMR assignments are provided. The UV-VIS and fluorescence spectra of the new ligands, together with a brief discussion of their electronic properties are included.

svrhu pronalaska potencijalnih markera za rano otkrivanje neuroloških poremećaja provedena je karakterizacija cijaninskih boja, kao i analiza njihovog vezanja s proteinom IbpA te nisu pronađeni uvjeti i radni parametri pogodni za vezanje. Okarakteriziran je i tripeptid fenilalanil-fenilalanil-alanin (FFA) te je ispitivan utjecaj biološke matrice odnosno, pokazano je da se FFA s Cu2+ veže u molarnim omjerima 1:1 i 2:1 dok su za kompleks FFA-Zn2+ ti omjeri: 1:1, 2:1, 3:1, 4:1. Analiza sastava metala cerebrospinalnog likvora ukazuje na to da su smanjene vrijednosti ukupnog željeza potencijalni indikator demijelinizirajućih bolesti. Spektrometrija masa (MS) odabrana je kao metoda za karakterizaciju potencijalnih markera neuroloških poremećaja i analizu sastava metala cerebrospinalnog likvora s obzirom da se primjenom raznih MS tehnika može brzo i efikasno okarakterizirati veliki broj različitih analita. Spektrometrija masa uz ionizaciju elektroraspršenjem (ESI-MS) odabrana je za karakterizaciju cijaninskih boja i tripeptida FFA, dok je analiza udjela metala u cerebrospinalnom likvoru provedena spektrometrijom masa uz induktivno spregnutu plazmu (ICP-MS). In order to find potential markers for early detection of neurological disorders, cyanine dyes were characterized. Suitable conditions and operating parameters for analysis of cyanine dye-IbpA protein interactions were not found. Also, tripeptide phenylalanine-phenylalanine-alanine (FFA) was characterized and analysis of the influence of biological matrix shows that FFA binds to Cu2+ in molar ratios: 1:1 and 2:1, while these ratios for complex FFA-Zn2+ are: 1:1, 2:1, 3:1 and 4:1. Furthermore, analysis of total metal concentrations in cerebrospinal fluid (CSF) shows that lower concentrations of iron can be an indicator for demyelinating diseases. Mass spectrometry (MS) is selected as a method for the characterization of potential markers for neurological disorders and analysis of selected metals in CSF, because different MS techniques are suitable for the fast and efficient characterization of a large number of analytes. Cyanine dyes and tripeptide FFA were characterized by electrospray ionization mass spectrometry (ESI-MS). The content of metals in CSF was analysed by inductively coupled plasma mass spectrometry (ICP-MS).

U ovom doktorskom radu sintetizirani su Cu(II) molekulski kompleksi [Cu(1-TsC-N3)2Cl2] i [Cu(1-MsC-N3)2Cl2] biološki aktivnih N-sulfonilcitozinskih (C) liganada s tosilom (Ts) i mezilom (Ms) te novi ciklam-TsC konjugati. Mannichova reakcija TsC liganda, paraformaldehida i ciklama u prisutnosti octene kiseline daje C-aminometilirani konjugat u kojem je ciklam vezan preko metilenskog mosta na C5 položaj citozina. Ista reakcija sa zaštićenim ciklamom daje C4 aminometilirani produkt. Pomoću ESI-MS metode provedena je studija stabilnosti i utjecaja biološki važnih metalnih iona (Na+, K+, Ca2+, Mg2+, Zn2+, Cu2+) na ligande, Cu(II) komplekse, te na poliaza makrocikličke konjugate. U interakciji s ligandima i Cu(II) kompleksima alkalijski metali uslijed elektrostatskih interakcija stvaraju klastere, dok je nastanak bis i tris te miješanih kompleksa uočen u interakciji s Ca2+ i Mg2+. Interakcija Zn2+ s ligandima i Cu(II) kompleksima rezultira nastankom monometalnih kompleksa kao i dimetalnih kompleksa zbog afniteta Zn2+ prema atomima kisika i dušika koji u strukturu uključuju molekule vode. Novi poliaza makrociklički konjugati u interakciji s CuCl2 stvaraju molekulske komplekse u kojima je CuCl2 u ciklamskom prstenu, a u interakciji s ZnSO4 nastaju ionski kompleksi u kojima je Zn2+ smješten u ciklamskom prstenu. Abstract In this doctoral thesis, Cu (II) molecular complexes [Cu(1-TsC-N3)2Cl2] and [Cu(1-MsC-N3)2Cl2] of biologically active N-sulfonylcytosine ligands (C) with tosyl (Ts) and mesyl (Ms) and new cyclame-TsC conjugates were synthesized. The Mannich reaction of TsC, paraformaldehyde and cyclame in the presence of acetic acid yields C-aminomethylated konjugate in which the cyclame was introduced through a methylene bridge at C5 position of cytosine. The same reaction with protected cyclame gives C4 aminomethylated product. Using ESI-MS method was conducted stability studies and the influence of biologically important metal ions (Na+, K+, Ca2+, Mg2+, Zn2+, Cu2+) to ligands, Cu (II) complexes, and polyaza macrocyclic conjugates. The interaction of ligands and Cu (II) complexes with biologically important metal ions results with formation of various metal complex. Alkali metals Na+ and K+ formed clusters due to the electrostatic inetractions. Bis, tris and mixed ligand complexes were observed upon mixing with Ca2+ or Mg2+ salt. Interaction with Zn2+ sieed monometal Zn2+ complexes and mixed ligand dimetal complexes that includ water molecules in the structures of the complexes because of affinity of Zn2+ for both O and N atoms. Both ions Cu2+ and Zn2+ were located within the cyclamic ring upon their interaction with polyaza macrocyclic conjugates. Newly formed Cu2+complexes were molecular while the ionic complexes were formed with zinc ions.

U održanju funkcije kožne barijere važnu ulogu imaju prirodni čimbenici zadržavanja vlage (engl. natural moisturizing factors, NMF) koji sudjeluju u regulaciji pH i hidrataciji rožnatog sloja kože te međustanični lipidi koji predstavljaju barijeru pri transportu tvari kroz kožu. Cilj ovog rada bio je razviti pouzdane i selektivne LC-UV i LC-MS metode za određivanje biokemijskih indikatora za procjenu funkcije kožne barijere, slobodnih masnih kiselina, aminokiselina i ceramida u rožnatom sloju izuzetom adhezivnim vrpcama. Razvijena je RP-LC-UV metoda za određivanje komponenata NMF-a, histidina, piroglutaminske kiseline, trans- i cis-urokanske kiseline i tirozina u rožnatom sloju kože te međustaničnoj tekućini. Ekstrakcija komponenata NMF-a s amonijakom u odnosu na tradicionalnu ekstrakciju jakim bazama omogućila je kraće vrijeme obrade uzorka zaobilazeći dodatni korak neutralizacije s jakom kiselinom. Analitička metoda za određivanje slobodnih masnih kiselina u rožnatom sloju kože temelji se na detekciji 3-aciloksimetil-N-metilpiridinij jodid (NMP) derivata primjenom RP-LC-ESI-MS i praćenju višestrukih tranzicijskih reakcija. Utjecaj matrice na analizu slobodnih masnih kiselina minimiziran je kvantifikacijom uz zamjenski (surogat) analit i unutarnju standardizaciju izotopno obilježenim NMP derivatom C19:0. Sadržaj slobodnih masnih kiselina oslobođenih iz adhezivne vrpce procijenjen je iz korelacije s C12:0 koji nije detektiran u rožnatom sloju. Razvijene analitičke metode pokazale su se dovoljno osjetljive i reproducibilne za istovremeno određivanje NMF-a odnosno slobodnih masnih kiselina dugih i vrlo dugih lanaca u normalnoj koži i koži oštećenoj uslijed djelovanja unutarnjih i okolišnih faktora. Ceramidne klase izolirane su iz humanog epidermisa optimiranim višestrukim ekstrakcijskim postupcima. Sintetski ceramidi III, IIIB i VI okarakterizirani su primjenom LC-ESI-MS tehnike. Natural moisturizing factors (NMF) play important role in the regulation of pH and hydration of the stratum corneum and the intercellular lipids form a barrier to transport of substances through the skin. The primary aim of this thesis was to develop reliable and selective LC-UV and LC-MS methods for the determination of biomarkers of skin barrier function including free amino acids, free fatty acids and ceramides obtained by tape stripping technique. Sensitive and robust RP-LC-UV method for determination of NMF components, histidine, pyroglutamic acid, trans- and cis-urocanic acid and tyrosine in the stratum corneum and interstitial fluid was developed. Extraction of NMF components with ammonia avoids a time consuming neutralization step as required with extraction procedures using strong base or acid. The method for determination of free fatty acids (FFAs) in the stratum corneum is based on detection of 3-acyloxymethyl-1-methylpyridinium iodide (NMP) derivatives in positive ionization mode using RP-LC-ESIMS and multiple reactions monitoring. To overcome the matrix effect, FFAs in the human stratum corneum were quantified by surrogate analyte method and internal standardization using isotope labelled derivatives of FFAs. The content of FFAs originated from the adhesive tape was calculated from the correlation with C12:0 signal not detected in the stratum corneum. Developed LC-UV and LC-ESI-MS methods showed to be reproducible and sensitive enough for simultaneous detection and quantification of NMF or eight long and very long chain FFAs in the normal and compromised human stratum corneum. Ceramide classes were isolated from human epidermis by multiple extraction steps. Synthetic ceramides III, IIIB and VI were characterized by LC-ESI-MS technique.