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The study of aminophosphonic acids and their esters is of current interest owing to their diverse biological properties and numerous applications in the medicinal and agrochemical fields. Another interesting aspect regarding this class of compounds arises from their ability of forming different types of metal complexes that might be also of interest as potential biologically active compounds. Thus, some aminophosphonate complexes of platinum group metals have been found cytotoxic against animal and human tumor cell lines. Continuing our research in this area, the synthesis, some spectroscopic, thermal and biological properties of diethyl 8-nitroquinolin-2-ylmethylphosphonate and its palladium(II) and platinum(II) dihalide complexes, have been reported. The results obtained were compared with those previously reported for diethyl quinolinylmethylphosphonates and their palladium(II) and platinum(II) complexes, and discussed with respect to their metal-binding behaviour and structure-activity relationship.

Continuing our research on the preparation of complexes with dialkyl esters of various aromatic aminophosphonic acids, we describe here the synthesis and structural characterization of palladium(II) complexes with diester derivatives of quinolinylaminophosphonates. Three types of palladium(II) halide complexes have been synthesized and studied. Diethyl and dibutyl [alpha-anilino-(quinolin-2-yl)methyl] phosphonates act as N, N-chelate ligands giving complexes cis-[PdLX2] (X=Cl, Br) (1-4), while their 3-substituted analogues form dihalidopalladium complexes trans-[PdL2X2] (5-8). Diethyl and dibutyl [alpha-(quinolin-3-ylamino)-N-benzyl]phosphonates give tetrahalidodipalladium complexes [Pd2L3X4] (9-12), containing one bridging and two terminal ligand molecules. New complexes were identified and characterized by IR, UV-vis, 1H, 13C and 31P NMR spectroscopic studies. The molecular and crystal structure of complexes 1-4 and 6 was determined by X-ray structure analysis.

Single-crystal X-ray analysis of three quinolin-2-yl derivatives S1-S3 formed in microwave-assisted reactions will be presented (Scheme 1). Microwave synthesis of aminophosphonate diesters yielded N-phenylquinoline-2-carboxamide (S1) and (4-aminophenyl)(quinolin-2-yl)methanone (S2) as main products, while the expected aminophosphonate diester (1) was present in the mixture in small quantities. Neat microwave reaction of quinoline-2-carboxaldehyde and aniline afforded anilinium quinoline-2-carboxylate (S3) along with the expected imine product (2). Both classical thermal synthetic procedures gave the expected aminophosphonate or the imine products in good yields without formation of the side-products S1-S3.

Structural characteristics and thermal stability of a series of dodecylammonium carrageenates formed by stoichiometric complexation of dodecylammonium chloride and differently charged carrageenans (k-, i- and λ -carrageenan, respectively) were investigated. IR spectral analysis confirmed the electrostatic and hydrogen bond interactions between the dodecylammonium and carrageenan species. X-ray diffraction experiments show increased ordering in the complexes compared to that in the parent carrageenans. Dodecylammonium carrageenates have a layer structure, in which a polar sublayer contains two layers of carrageenan chains and a nonpolar sublayer consists of fully interdigitated conformationally disordered dodecylammonium chains electrostatically attached to the carrageenan backbone. The major factor that determines the dodecylammonium carrageenate structure is cationic surfactant, while the carrageenans moiety plays a major role in determining thermal properties.

Nakon otkrića antitumorske aktivnosti cisplatine i njezinih analoga, te njihove vrlo uspješne kliničke primjene u liječenju određenih tipova tumora, intenzivno se istražuju novi platinski kompleksi i kompleksi drugih metala s ciljem dobivanja citostatika s boljim antitumorskim djelovanjem i manje izraženim nuspojavama. Naša istraživanja u tom području usmjerena su na komplekse platine i paladija s derivatima aminofosfonskih kiselina. U ovom radu dat je pregled kompleksa platine(II) i paladija(II) s dietil i monoetil 2- i 8-kinolilmetilfosfonatima te rezultati testiranja njihove in vitro antitumorske aktivnosti prema KB stanicama karcinoma kože kod ljudi i L1210 stanicama leukemije kod miša. Nekoliko kompleksa pokazalo je visoku aktivnost. Razmatran je odnos antitumorske aktivnosti kompleksa o njihovim strukturnim i fizičko-kemijskih svojstvima.

Synthetic and spetroscopic studies of alpha-aminophosphonate derivatives continue to attract considerable attention due to various biological properties of these organophosphorus compounds [1]. One of the simpliest synthetic methods towards aminophosphonates is Kabachnik-Fields reaction, three-component one-pot reaction of amine, carbonyl and hydrophosphorous compound [2]. We have recently directed our attention towards microwave-assisted synthesis of aminophosphonate derivatives [3]. Using Kabachnik-Fields approach, a series of aminophosphonate diester derivatives was prepared and some unexpected by-products were isolated. In this work, we present the mass spectrometric study of diester 2-quinolylaminophosphonate, along with the diester and unusual monoester 3-quinolylaminophosphonate derivatives. [1] Kafarski, P., Lejczak, B., in: Aminophosphonic and Aminophosphinic Acids. Chemistry and Biological Activity, Kukhar, V.P., Hudson, H.R. (Eds), John Wiley & Sons, Chichester, 2000, pp 407. [2] Cherkasov, R.A., Galkin, V.I., Russ. Chem. Rev. 67 (1998) 857. [3] (a) Tušek-Božić, Lj., Juribašić, M., Komac, M., Cmrečki, V., Zrinski, I., Balzarini, J., De Clercq, E., Lett. Org. Chem. 4 (2007) 332 ; (b) Juribašić, M., Stella, L., Marinić, Ž., Vinković, M., Traldi, P., Tušek-Božić, Lj., Lett. Org. Chem. 6 (2009) 11.

The synthesis and characterization of sodium and potassium benezeneazophosphonate complexes obtained by reaction in the solid state under microwave irradiation of alkali salts (Na/KA1 and Na/KA2) with crown ethers containing 18-membered (dibenzo-18-crown-6 and mtb-dibenzo-18-crown-6), 24-membered (dibenzo-24-crown-8) and 30-membered (dibenzo-30-crown-10) macrocyclic ring, was described. The simple work-up, eco-friendly solvent free reaction resulted in the formation of the mononuclear complexes in which sodium/potassium ion was bonded to oxygen atoms of the macrocycle and the phosphonic acid oxygen. The biological activity of the free crown ethers, alkali benezeneazophosphonate salts and their complexes were determined by evaluation of their antitumor activity in vitro in human T-lymphoblast CEM/0, murine leukemia L1210/0 and murine mammary carcinoma FM3A/0 cells, as well as of their antiviral activity against the human immunodeficiency viruses HIV-1 and HIV-2. The investigated compounds showed no or only marginal anti-HIV activity, whereas, all free crown ethers and their complexes demonstrated antitumor activity, which was especially high in the case of mtb-dibenzo-18-crown-6 and its complexes.

Presented platinum(II) complexes with phosphonate ligands represent structurally and biologically interesting class of compounds. Depending on the reaction conditions, various types of complexes of the same ligand can be obtained. Furthermore, complexes of 8-dqmp show medium cytostatic activity. Synthesis of new structurally different phosphonate ligands and their palladium as well as platinum complexes could be helpfull in elucidating rather complicated structure-activity relationship for these kind of compounds.

Structural characteristic and thermal stability of a series of dodecylammonium carrageenates (abbreviated as (DDA)KC, (DDACl)2IC and (DDACl)3LC) formed by stoichiometric complexation of dodecylammonium chloride and differently charged carrageenans (with ideally one, two or three sulfate groups, k-, i- and λ -carrageenan, respectively) were investigated. FTIR investigations confirmed the electrostatic and hydrogen bond interactions between the dodecylammonium and carrageenan species. XRD analysis revealed the formation of a surfactant bilayered structure with irregular conformations of dodecylammonium chains in conjunction with the carrageenan chains. Slightly enhanced local ordering of dodecylammonium chains within (DDACl)2IC can be explained with sulfate groups symmetrically located on the both side of polysaccharide backbones and bonded paraffin chains. Location of one or three sulfate groups in the k- and λ -carrageenan backbones induced asymmetric binding of paraffin layers to sulfate groups and greater disordering inside a bilayer. Complexation of carrageenans with DDACl affected their thermal behavior. All (DDA)nCAR were less thermally stable, i.e. the temperature of their initial decomposition was lower than that of parent compounds. Microscopic observation confirmed that the melting occurs just in the beginning of their decomposition. Common characteristics of (DDA)nCAR DSC heating curves are expressed exothermic transitions and smaller molar enthalpy change associated with decomposition/melting than for parent compounds.

The synthesis of alpha-aminophosphonate derivatives has attracted current interest in the organic and medicinal chemistry due to important biological and pharmacological properties of these organophosphorus compounds.[1] Another interesting aspect regarding this kind of compounds arises from their ability of forming various types of transition metal complexes, which might also be of interest owing to their biological activity.[2] The classical Kabachnik-Fields reaction, a three-component one-pot reaction of amine, carbonyl compound (aldehyde or ketone) and hydrophosphoryl compound, has proven its great synthetic potential and significance as one of the simplest approaches to alpha-aminophosphonates.[3] We have directed out attention to investigations on the course of microwave-assisted one-pot three-component reaction of quinoline-3-carboxaldehyde and aniline (Scheme 1) as well as 3-aminoquinoline and benzaldehyde (Scheme 2), respectively, with diethyl phosphite. Here, we present 1H and 31P NMR, MS and IR spectroscopic characterization of unusual monoester phosphonate derivatives (2, 3, 5) isolated along with diethyl phosphonates (1, 4).

Aminophosphonic acids and their esters have attracted continuous attention because of their wide range biological properties and potential applications in the pharmacological and agrochemical fields [1]. These organophosphorus compounds are also known as good complexing agents for various transition metals, of which platinum group metals form complexes with noticeable antitumor activity [2]. One of the simplest synthetic routes to alpha-aminophosphonates is the Kabachnik-Fields reaction, a three-component one-pot reaction of amine, carbonyl compound (aldehyde or ketone) and hydrophosphoryl compound [3]. Recently, we focused our attention on the influence of microwave irradiation on the Kabachnik-Fields synthesis of quinoline-based alpha-aminophosphonates [4]. In studied reactions with 3-quinoline derivatives, along with main products diethyl phosphonates (1, 4), unusual monoester phosphonate derivatives (2, 3, 5) were isolated. We present here the NMR characterization of compounds 1-5 using various one- and two-dimensional 1H, 13C and 31P NMR spectroscopic methods. [1] P. Kafarski, B. Lejczak, in Aminophosphonic and Aminophosphinic Acids. Chemistry and Biological Activity ; V.P. Kukhar, H.R. Hudson (Eds.) ; John Wiley & Sons: Chichester, 2000 ; pp 407-442. [2] Lj. Tušek-Božić, V. Cmrečki, J. Balzarini, E. De Clercq, Lett. Drug Des. Discovery 3 (2006) 528-533 ; and references cited therein. [3] R.A. Cherkasov, V.I. Galkin, Russ. Chem. Rev. 67 (1998) 857-882. [4] Lj. Tušek-Božić, M. Juribašić, M. Komac, V. Cmrečki, I. Zrinski, J. Balzarini, E. De Clercq, Lett. Org. Chem. 4 (2007) 332-338.

Zahvaljujući raznovrsnim biološkim i farmakološkim svojstvima derivata alfa-aminofosfonata, njihova sinteza već dulje vrijeme privlači pozornost. Derivati alfa-aminofosfonata strukturni su analozi aminokiselina. Stoga mogu sudjelovati u regulaciji metabolitičkih puteva, te djelovati kao inhibitori niza metaloenzima čiji su supstrati aminokiseline. U ovom radu istražena je Kabachnik-Fields metoda sinteze 3-kinolilnih derivata alfa-aminofosfonata uz mikrovalno grijanje. Reakcije kinolin-3-karboksaldehida i anilina, te 3-aminokinolina i benzaldehida s dietil-fosfitom izvedene su u jednom koraku bez korištenja otapala. Glavni produkt reakcije s anilinom je dietil [alfa-anilino-(3-kinolilmetil)]fosfonat 1 (78 %). Izolirana su također dva sporedna produkta, odgovarajući monoester 2 (3 %) i trifosforni derivat 3 (7 %). Reakcija s benzaldehidom daje dietil [alfa-(3-kinolilamino)-N-benzil]fosfonat 4 (66 %), te je kao sporedni produkt izoliran etil N-(3-kinolil)amidofosfonat 5 (9 %), kod kojega je uočena amido-imino tautomerija. Novi fosforni spojevi okarakterizirani su elementnom analizom, te spektroskopskim (1H, 13C i 31P NMR, IR, MS) i termogravimetrijskim metodama (TG i DTA).

There has been a continued interest in the chemistry and biochemistry of phosphonic and aminophosphonic acid derivatives because of their wide range of biological and pharmacological properties, with possible application from medicine to agriculture. Another interesting aspect regarding this kind of compounds arises from their ability of forming metal complexes, which might be also of interest in living systems. In this field our systematic study is directed to platinum(II) and palladium(II) complexes of quinoline and aniline-based alkyl phosphonates, which might be of interest as potent antitumor agents [1, 2]. In this report we describe the synthesis, spectroscopic analysis and biological properties of platinum(II) and palladium(II) complexes of monoethyl quinolyl-8-ylmethylphosphonate. This organophosphorus ligand depending on reaction conditions forms neutral and ionic metal complexes. In the basic media acts as a bidentate ligand through the quinoline nitrogen and the deprotonated phosphonic acid group, while under acidic conditions are formed the quinolinium tetrahaloplatinum, tetrahalopalladium, trihalopalladium and hexahalodipalladium salt complexes, respectively. All complexes were evaluated for their in vitro cytostatic activity in an epidermoid human carcinoma (KB) and murine leukaemia (L1210) cell lines. The results obtained are compared with those obtained for the platinum(II) and palladium(II) complexes of the corresponding dialkyl esters of quinolyl-8-ylmethylphosphonate and discussed with respect to their structure-activity relationship.

Utjecaj dodecilamonijevog klorida (DDACl) na geliranje karagenana ( - i  -karagenan) istražen je različitim tehnikama i metodama (reološka mjerenja, konfokalna laserska pretražna mikroskopija i difrakcija X-zraka). Dodatak DDACl mijenja strukturu gela od nano do makro razine. Na makroskopskoj razini razlikuju se dva koncentracijska područja ; područje ispod kritične micelarne koncentracije u kojem nastaju mutni gelovi i micelarno područje u kojem dolazi do razaranja strukture gela i taloženja. Utjecaj monomerne koncentracije DDACl na strukturu gela na nano razini istražen je reološkim mjerenjima. Svi uzorci gela pokazuju pseudoplastična svojstva, slična karagenanima bez površinski aktivne tvari. Promjene parametara tečenja s rastućom koncentracijom DDACl posljedica su nastalih domena površinski aktivne tvari unutar strukture gela, tj. stvara se bikontinuirano fazno uređenje. Porastom koncentracije DDACl postepeno se razara struktura gela i povećava uređenost domena površinski aktivne tvari. U blizini micelarnog područja odvajanje faza na mikrorazini, vizualizirano konfokalnom laserskom pretražnom mikroskopijom, upućuje na izrazite strukturne promjene gela. Talozi nastali u micelarnom području istraženi su difrakcijom X-zraka. Analiza difraktograma je pokazala da nastaju lamelarne stukture DDACl povezane lancima karagenana. Bolja lokalna uređenost i pravilnije slaganje lamela uočeno je kod karagenana veće gustoće naboja na lancima, tj. kod  -karagenana.

Opisan je prvi primjer sinteze kompleksnog spoja dobivenog reakcijom jedne alkalne soli i heteromakrocikličkog spoja primjenom mikrovalnog zračenja u čvrstom stanju. Jednostavnom i ekološki prihvatljivom (eco-friendly) reakcijom bez otapala natrijevog etil [4-benzenazoanilino)-N-benzil]fosfonata i petnaesteročlanog dioksa-diaza makrocikličkog spoja 5, 6, 14, 15-dibenzo-1, 4-dioksa-8, 12-diazaciklopentadeka-5, 14-diena dobiven je dinuklearni kompleks u kojemu su dva atoma natrija premoštena s kisikovim atomima dviju fosfonatnih skupina. Natrij je vezan i na sva četiri donorna atoma makrocikla. Natrijev kompleks je identificiran i karakteriziran na osnovi elementarne i termičke (TG, DTA) analize te spektroskopskih metoda (IR, 1H i 13C NMR, ESI i LDI MS). Reakcija kompleksiranja uz mikrovalno zračenje uspoređena je s reakcijama provedenih uz klasično zagrijavanje u čvrstom stanju i u otopini.

Biopolymers and surfactants play an important role in the natural world as well as in modern technologies. The interactions between these two types of molecules, vastly differing in their dimensions and properties, frequently produce cooperative effects on the physico-chemical properties of their mixtures. In this work, rheological measurements, confocal laser scanning microscopy and X-ray diffraction were used to study the spatial organization of dodecylammonium chloride (DDACl) in gels of  - and  -carrageenans. The increase of DDACl concentration led to the changes of gel structure from nano to macro-level. At the macroscopic level, two phase regions have been differentiated ; one below the surfactant micellar region containing turbid gel and the other in the micellar region characterized by gel collapsing. The effect of monomer DDACl concentration on gel structure at the nano level was detected by rheological measurements. All gel samples exhibited shear thinning behavior, well fitted by power law equation, indicating that they maintain mainly carrageenan rheological properties. The change of flow behavior parameters with increasing DDACl concentration might be ascribed to the formation of surfactant domains inside gel networks. Progressive increase of surfactant concentration caused gradual break down of the gel structure and enhanced ordering of surfactant molecules. In the vicinity of the critical micelle concentration, the appearance of microphase separated domains, visualized by confocal laser scanning microscopy indicated pronounced structural changes of both,  - and  -carrageenan gels. X-ray diffraction of collapsed gels revealed the formation of a bilayered surfactant structures in conjunction with the carrageenan chains. The increase of DDACl concentration enhanced ordering and growth of mesostructural domains consisting of stacked bilayers. Both, local ordering of bilayers and regular stacking of lamellae revealed stronger electrostatic interactions between surfactant and carrageenan with higher charge density on chains.

Aromatske fosfonske kiseline i njihovi derivati koji sadrže piridinski ili kinolinski prsten zanimljivi su zbog svojih antibakterijskih, herbicidnih i antiviralnih svojstava, pa nalaze primjenu u agrokemijskoj i farmaceutskoj industriji. Zbog svojih sposobnosti da vežu prijelazne metale koriste se u analitici kao ekstraktanti i kompleksirajući agensi, dok su kompleksi platinske grupe metala veoma važni zbog svog antitumorskog djelovanja. Naša višegodišnja istraživanja usmjerena su na komplekse paladija(II) i platine(II) s dialkil esterima alpha-aminofosfonskih kiselina te je pripravljen niz kompleksnih spojeva koji su pokazali visoku in vitro antitumorsku aktivnost. U ovom je radu opisana sinteza niza halogenidnih i acetatnih kompleksa paladija(II) s dietil i dibutil esterima [alpha-anilino-(2-kinolilmetil)]fosfonske kiseline i [alpha-(3-kinolilamino)-N-benzil]fosfonske kiseline. Identifikacija i karakterizacija novih kompleksnih spojeva izvršena je na osnovi kemijske i spektroskopske analize (IR, 1H i 13C NMR, spektri masa).

Following the discovery of the cytostatic activity of cisplatin and its analogues, there is a continuing interest in the development of new platinum-based anticancer drugs with improved cytotoxicity and therapeutic properties. The studies on this type of compounds included also the substitution of platinum by its homologue palladium with similar coordination behavior in order to investigate the effects of the metal on the structural and biochemical properties of the complexes. Our systematic study is directed to palladium and platinum complexes of quinoline and aniline-based alkyl phosphonates as an effort to obtain metal complexes with potential antitumor and antiviral activity. We report here the synthesis, some spectroscopic properties (IR, 1H NMR, MS) and biological evaluation of new platinum(II) complexes of diethyl 8-quinolylmethylphosphonate (8-dqmp). The cytostatic activity of complexes was assayed in vitro on epidermoid human carcinoma KB, murine leukemia L1210/0 and human T-lymphoblast Molt4/C8 and CEM cell lines, and the antiviral assays were carried out in vitro in HEL, Vero and HeLa cell cultures infected with a variety of DNA and RNA viruses. The results obtained are compared with those of the palladium(II) chloride, bromide and acetate complexes of the same ligand and are discussed with respect to their structure-activity relationship. The greatest cell growth inhibitory effects display palladium dichloro adduct and acetate bridged dimmer, which may be regarded as having antitumor properties since their IC50 values are lower than 10 micromolar.

There is a current interest in platinum(II) and palladium(II) complexes with nitrogen donor ligands not only because of their wide-range application in organic synthesis and catalysis, but also owing to their biological and pharmacological importance. A number of these compounds have shown good cell growth inhibitory effects. In this field our study is directed to complexes of quinoline and aniline-based alkyl phosphonates. We report here the synthesis, some spectroscopic properties and biological evaluation of new palladium(II) acetate complexes of diethyl 8-quinolylmethylphosphonate and monoethyl 2-quinolylmethylphosphonate (2-Hmqmp). These organophosphorus ligands form different type of binuclear acetate-bridged complex, that with [C, N] and [N, O] cyclopalladation, respectively. Comparative studies were performed with results obtained for the selected palladium(II) chloride complexes of the same phosphonate ligands and a structure-activity relationship was discussed. It was found that most of complexes demonstrated distinct in vitro cytostatic activity, but showed no or only marginal antiviral activity in different assay systems.

U radu je data usporedba klasične i mikrovalne sinteze dialkil fosfonata: [alpha-anilino-(2-kinolilmetil]fosfonske kiseline i [alpha-(3-kinolilamino-N-benzyl]fosfonske kiseline.

In connection with our interest in the complexes of aminophosphonate derivatives of potential biological and pharmacological importance, we report the synthesis, characterization and biological evaluation of platinum(II) complexes of diethyl ester of quinolyl-8-ylmethylphosphonic acid (8-dqmp). It was shown that complexes demonstrated distinct antitumor activity in some animal and human tumor cell lines, but showed no or only marginal antiviral activity in the examined DNA and RNA assay systems.

The synthesis, some spectroscopic properties and antitumor activity of new molecular and ionic platinum(II) complexes of diethyl ester of 8-quinolylmethylphosphonic acid (8-dqmp) have been reported. The new complexes were characterized on the basis of elemental and thermogravimetric analyses, magnetic and conductometric measurements, and by infrared and NMR spectral studies. As a preliminary assessment of their biological activity, complexes were evaluated for their in vitro antutumor activity in an epidermoid human (KB) and murine leukemia (L1210) tumor cell lines.

Različitim mikroskopskim metodama istražen je utjecaj duljine poveznika na asocijaciju u otopini te termička svojstva u krutom stanju dimernih površinski aktivnih tvari.

Liquid phase and gas phase metallation of following crown ethers: 18-crown-6 (18C6), dibenzo-18-crown-6 (DB18C6), bis(4-tert-butylbenzo)-18-crown-6 (mtb-DB18C6), bis(3, 5-di-tert-butylbenzo)-18-crown-6 (dbt-DB18C6) and bis(4-hexadecylbenzo)-18-crown-6 (hd-DB18C6) with Li+, Na+, K+, Rb+ and Cs+ ions was investigated by fast atom bombardment (FAB), electrospray ionization (ESI) and laser desorption/ionization Fourier transform (LDI-FT) mass spectrometry. Special attention was paid to the relative rates of formation and stability of monomeric products, as well as to the addition of a second crown ether molecule to them.

Dat je kratki opis kompleksnih spojeva, njihova podjela, važnost i primjena.

The crystal structures of the potential anti-tumour agents monoethyl (alpha-anilino-N-benzyl)phosphonate (I) and its 4-azobenzene-substituted derivative monoethyl [alpha- (4-benzeneazoanilino) -N-benzyl]phosphonate (II) are described. The zwitterionic form of (I) and the neutral molecular form of (II) were observed, which is fully in accordance with the previously reported spectroscopic studies. In both structures hydrogen bonding induces the formation of the zig-zag head-to-head double layers parallel to the crystallographic b axis.

By reaction of the enantiomerically pure 7-bromo-1, 3-dihydro-1-methyl-3(S)-methyl-5-(2'-pyridyl)-2H-1, 4-benzodiazepin-2-one, (+)-1, with CuCl2 &middot ; ; 2H2O in a mixture of absolute ethanol and dichloromethane, dichloro-[7-bromo-1, 3-dihydro-1, 3-dimethyl-5-(2'-pyridyl)-2H-1, 4-benzodiazepin-2-on-N, N, O]copper(II), (&plusmn ; ; )-2, was obtained. In both structures, characteristic boat conformation of the seven-membered benzodiazepine ring was observed. Complex 2, which was isolated as a racemic compound, revealed a slightly distorted trigonal bipyramid. Copper(II) is coordinated by two azometine nitrogen atoms, two chlorine atoms and the lactam oxygen of a neighbouring molecule. In this way an infinite chain of complex molecules was formed in the crystal. The chemical behaviour of the ligand 1 upon Cu(II) coordination was compared with its 3-hydroxymethyl and 3-acetoxymethyl analogues.

Crown ethers and their complexes have received a continuous attention because of their widespread chemical and biological application. It was shown that the alkali metal chemistry of biologically important transport agents, such as some naturally occurring antibiotics, parallels in many aspects to that of the crown ethers towards these metal ions. For this reason these compounds are used as synthetic model systems for examination of the selective ion-transport through the cell membranes. In this paper we report the complexation of dibenzo-24-crown-8 with potassium and ammonium hexafluorophosphates, as continuation of our systematic investigation on the alkali and ammonium salt complexes with different crown ethers both in solution and in the solid state. The new complexes were identified and characterized by elemental, spectroscopic (IR, UV/VIS, 1H NMR) and X-ray structural analyses. The potassium complex crystallizing in two polymorphic forms: one with nine and the other with eight coordinated cation. The conformation of the crown ring in one of them is identical with the conformation in ammonium complex, where cation forms hydrogen bonds with the oxygen atoms of the polyether ring. The results obtained are compared with those obtained for the corresponding hexaflurophospahate complexes of dibenzo-18-crown-6 and dibenzo-30-crown-10. The coordination behaviour of crown ethers towards cations is influenced by the size and charge of the linked cation and by the flexibility and cavity size of the macrocyclic compound, but it was shown that the cation-cavity size relation is not the crucial factor for the structure of these complexes.

U svrhu ispitivanja svojstva kompleksiranja natrijevog iona s makrocikličkim spojem 5, 6, 14, 15-dibenzo-1, 4-diokso-8, 12-diazaciklopentadeka-5, 14-dienom (L), provedene su reakcije L s pet različitih natrijevih soli u metanolu. U svakom slučaju dobiven je kompleks koji ne sadrži natrijev kation, što je potvrđeno i rendgenskom strukutrnom analizom. Izolirani kompleksni spojevi, uz anion iz upotrebljene natrijeve soli [pikrat (1), perklorat (2), tetrafluoroborat (3), tiocijanat (4) i tetrafenilborat (5)] sadrže proton koji je ili vezan na jedan od dušika u makrociklu (1 , 4 i 5) ili je vodikovim vezama povezan s anionom (2 i 3). Odnos protona i makrocikličkog liganda je 1:1 u kompleksima 1 i 5 odnosno 1:2 u kompleksima 2, 3 i 4. Novi spojevi su karakterizirani elementarnom kemijskom i rendgenskom strukturnom analizom te različitim spektroskopskim metodama. Analiziran je utjecaj aniona na konformaciju makrocikla. Istraženi su razlozi različitog smještanja protona koji uravnotežuje naboj aniona. Analiziran je izostanak koordinacijskog vezivanja natrija na makrocikl s kemijskog i strukturnog aspekta.

Three new Pd(II) complexes, i.e. [PdCl_2L]_2 (A), PdCl_2L_2 (B) and [Pd(mu-Cl)(L-H)]2 (C), each with two diethyl [alpha-(4-benzenazoanilino)-2-hydroxybenzyl]phosphonates (L) bound to either one or two palladium atoms, are synthesized and characterized by elemental analysis, X-ray powder diffraction, magnetic measurements and by IR, UV/Vis and 1H NMR studies. B and C are additionally characterized by 13C and 31P NMR and ES-MS studies. In DMF solution adducts A and B undergo spontaneous rearrangement into the cyclopalladated complex C. Dynamic 1H NMR study of this rearrangement as well as of the reactions of L with PdCl_2 and Na_2PdCl_4 revealed a complex equilibrium in DMF solutions and enabled the formation mechanism of all involved species to be resolved. The complex A is immediately solvolyzed producing two molecules of intermediate M [PdCl_2(L)(DMF)]. M was also the first intermediate in the reaction of L with PdCl_2. Once present in concentration above 10^-5 mol dm^-3 M dimerizes very fast into chloro-bridged dimer [PdCl(mu-Cl)(L)]2 (D) which undergoes cyclopalladation and converts into the complex C. The formation of C from the intermediate D is clearly demonstrated by the concentration dependence of the cyclopalladation reaction which has order greater than one. Chloride ions, released by cyclopalladation, react with D by splitting chloro-bridge and binding to metal atoms to produce byproduct [PdCl_3(L)]- (T). The same species (T) are formed in the reaction of L with Na2PdCl4 whereby a chloride ion is replaced by the ligand L. The complex B undergoes similar, but slower, solvolytic reaction producing M and L while further reaction steps are identical as in the solvolysis of A.

Three quaternary, asymmetric, dimeric surfactants with two hydrocarbon chains differing in length (tetradecyl and dodecyl) and with different polymethylene spacers N, N, N&cent , N&cent -tetramethylethane (12-2-14), N, N, N&cent , N&cent -tetramethylehexane (12-6-14) and N, N, N&cent , N&cent - tetramethyldecane (12-10-14) were prepared. Their solid phase and thermal behavior were examined by X-ray diffraction, spectral, thermal and optical microscopic studies. Structure of 12-2-14 contains interdigitated alkyl chain layers, 12-6-14 monolayers of molecules with tilted alkyl chains, while 12-10-14 exhibits liquid crystalline structure even at room temperature. Molecules with a shorter spacer are all in cis-configuration, while those with longer ones are all in trans-configuration. On heating all compounds exhibited the conformational disordering of the alkyl chain during phase transitions in the solid state at lower temperatures and the bidimensional disordering of the ionic layers during the solid crystalline to liquid crystalline transitions. Phase transitions in the solid state include structural varieties, polymorphs and smectic liquid crystals. Crystal structure, number of phase transitions and thermodynamic parameters strongly depend on the spacer length ; i.e., on the global configuration of molecules. Temperatures of the first solid state, solid crystal &#8211 liquid crystal and liquid crystal &#8211 isotropic melt transitions exhibit maximum for s = 6. Polarizing microscopy revealed characteristic textures of the smectic phases in the case of 12-2-14 and 12-10-14.

The study of phosphonic and aminophosphonic acid derivatives is of current interest owing to great importance of these compounds in metabolism and some biological processes. Another interesting aspect regarding this kind of compounds arises from their ability of forming different types of metal complexes, which might be also of interest in living systems. In recent years, a number of aminophosphonate complexes of Pt(II) and Pd(II) have been found to possess significant cytostatic activity. Continuing our research on this class of compounds, the synthesis, some spectroscopic properties and cytostatic activity of the novel Pt(II) complexes with diethyl and monoethyl 2-quinolylmethylphosphonate have been reported. These organophosphorus ligands depending on reaction conditions form neutral or ionic Pt(II) complexes. Acting as N-monodentate ligand form dihalide adducts PtL_2X_2, by bonding in the N, O-bidentate manner give PtL_2 chelates, while under acidic conditions are formed the ion-pair salt complexes [(LH)_2(PtX_4)] or [(LH)_2(Pt_2X_6)] (X=Cl, Br), with protonated quinoline ligand as cation and tetrahaloplatinate or hexahalodiplatinate complex as anion. The coordination behaviour of diethyl and monoethyl phosphonates towards Pt(II) ion as well as spectroscopic and biological properties of their Pt(II) complexes were discussed with respect to results obtained for the corresponding Pd(II) derivatives.

The ^1H, ^13C and ^31P NMR study of monoethyl (HL1) and monobutyl (HL2) esters of (alpha-anilino-N-benzyl)phosphonic acid and their metallocyclic dipalladium complexes (Pd_2L_, L=L1, L2) in DMSO has been performed. The NMR analysis was made on the basis of one- and two-dimensional homo- and heteronuclear experiments including ^1H, ^13C, ^31P, APT, ^1H-^1H COSY, ^1H-^13C COSY, gs-HMQC and gs-HMBC NMR techniques. The results obtained were discussed with respect to those of some palladium(II) complexes reported for various anilinobenzylphosphonate derivatives.

Infrared spectra of monoethyl (HL1) and monobutyl (HL2) esters of (alpha-anilino-N-benzyl)phosphonic acid, their sodium salts (NaL1 and NaL2) and dipalladium(II) complexes (Pd_2L_4, L=L1, L2), have been studied. Monoalkyl esters were found to have zwitterion structure. Their binuclear [N, O] metallocyclic complexes possess four organophosphorus ligands bridged by two palladium atoms through the aniline nitrogen and the deprotonated phosphonic acid oxygen. The spectral results obtained were discussed with respect to those of the corresponding 4-azobenzene-substituted anilinobenzylphosphonate derivatives.

The object of the present research was to develop an efficient procedure for mineralization of various types of biologically active palladium(II) complexes of quinoline- and aniline-based phosphonates as well as to develop the method that was compatible with determination of palladium and phosphorus in these compounds.

The chemistry and biochemistry of a-aminophosphonic acids and their derivatives have attracted current interest owing to their wide range of biological properties, with possible application from medicine to agriculture as enzyme inhibitors as well as antibacterial, anticancer and herbicidal agents. Recently, increasing attention has been devoted to nucleoside and nucleotide phosphonate analogues as broad-spectrum antiviral agents. Studying this class of phosphonic acid derivatives, we now report the synthesis, spectroscopic characterization and biological evaluation of novel dialkyl 2- and 3-quinoline-substituted a-aminophosphonates. As a preliminary assessment of their biological activity, complexes were evaluated for their in vitro cytostatic activity against human T-lymphoblast Molt4/C8 and CEM/0 cell lines and the murine leukemia L1210/0 tumor cell line, as well as for in vitro antiviral activity in different assay systems including a broad spectrum of DNA and RNA viruses. None of the examined compounds were found to exhibit cytostatic activity at therapeutically meaningful concentrations.

A series of dissymmetric gemini surfactants were prepared from n-dodecyldimethylammonium and n-tetradecyldimethylammonium bromide and linked by polymethylene chains (spacer), the number of carbon atoms in a spacer being 2, 6 and 10. Their solid phase properties were examined by X-ray diffraction, spectral, thermal and optical microscopic studies. The increase of the number of carbon atoms in the spacer changed the structure and thickness of bilayers. On heating, successive phase transitions (several solid crystalline-solid crystalline, solid crystalline-liquid crystalline and liquid crystalline-isotropic liquid) were observed. The number of polymorphs depended on the lengths of the spacer. Polarizing microscopy revealed a characteristic texture of the smectic phase. Crystallization from melted samples was kinetically controlled.

In ethanolic solution of CuCl2.2H2O enantiomerically pure 7-bromo-1, 3-dihydro-3-hydroxymethyl-1-methyl-5-(2'-pyridyl)-2H-1, 4-benzodiazepin-2-one, (+)-1, afforded dichloride adduct 3, [CuCl2(1)], isolated as a racemic compound. The replacement of one chlorine with DMSO gave complex 4, [CuCl(1-H)(DMSO)]. The C(3)-oxygenated product appeared as a racemic N, N, O-tridentate ligand in a square-pyramidal complex 5. A product of oxidative ring contraction of (+)-1 yielded 6-bromo-1, 4-dihydro-4-ethoxy-1-methyl-4-(2'-pyridyl)-1, 3-quinazoline, which was found as an N, N-bidentate ligand in the tetrahedral complex 6. 3-Acetoxymethyl-7-bromo-1, 3-dihydro-1-methyl- 5-(2'-pyridyl)-2H-1, 4-benzodiazepin-2-one, (ą)-2, afforded the square-pyramidal complex 7, [CuCl2(2)]. In this complex the lactam oxygen atom of a neighbouring molecule completes a five-fold coordination forming an infinite chain of connected polyhedra in the crystal. A product of oxidative ring contraction of 2 leads to 6-bromo-1, 4-dihydro-4-hydroxy-1-methyl-4-(2'pyridyl)-1, 3-quinazoline, which acts as an N, N-bidentate ligand in the centrosymmetric binuclear five-coordinated Cu(II)-complex 8. In this complex di-ľ-chloro bridges are asymmetrical: one is of an appical coordination site [Cu-Cl, 2.820 (7) Ĺ], whereas the other one is of an equatorial site [Cu-Cl, 2.252 (5) Ĺ]. The complexes are characterised by IR spectra and X-ray structure analysis. Mechanisms of racemization, oxygenation and ring contraction are discussed.