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EN
Although polyamines (PA) belong to relatively simple aliphatic substances, their role in life processes of animals and plants is of key importance [1–5]. The group of the most important amines, called biogenic ones includes: Spermine (Spm): H2N(CH2)3NH(CH2)4NH(CH2)3NH2 Spermidine (Spd): H2N(CH2)3NH(CH2)4NH2 Putrescine (Put): H2N(CH2)4NH2. Of secondary importance are homologues of biogenic amines, occurring in lower contents in living organisms [2, 6–8]: 1,3-diaminopropan: H2N(CH2)3NH2 Cadaverine: H2N(CH2)5NH2 Homospermidine: H2N(CH2)4NH(CH2)4NH2 Norspermine (3,3,3-tet): H2N(CH2)3NH(CH2)3NH(CH2)3NH2 Thermospermine: H2N(CH2)3NH(CH2)4NH(CH2)4NH2 Caldopentamine: H2N(CH2)3NH(CH2)3NH(CH2)3NH(CH2)3NH2. The first polyamine discovered in a living organism was tetramine, a spermine crystallised out of sperm in 1678 by Van Leewenkeuk [9]. Putrescine was discovered in the end of the 19th century in microbes and then triamine: spermidine was discovered in the beginning of the 20th century [2]. Later studies have shown that in animal cells spermidine and spermine occur at elevated levels, while in prokaryotes spermidine and putrescine contents are dominant. Putrescine, spermidine, 1,3-diaminopropan, homospermidine, norspermidine, and norspermine have been found in many gramnegative bacteria and algae [7, 10, 11]. Total concentration of PA in living organisms is on the order of millimols, however, the concentration of free polyamines is much lower. A low level of free amines follows from the fact that they are involved in noncovalent interactions with biomolecules occurring in living organisms such as nucleic acids, proteins, or phospholipids. High concentrations of non-bonded polyamines have been detected first of all in young molecules in the process of growth, in particular in rapidly proliferating cancer cells [6, 12]. Elevated levels of free polyamines have been observed, e.g. in breast, colon, lung, prostate, and skin tumours, accompanied by changed levels of enzymes responsible for biosynthesis and catabolism of polyamines. Because of the increased level of free polyamines and a tendency of their interaction with nucleic acids and other bioligands, these compounds have become objects of intense study [1, 13–19]. There is no doubt that the regulation of biosynthesis of polyamines and catabolism is one of the most important pathways in the search strategy for chemoprevention and chemotherapeutic drugs [14, 15, 20–36]. The present state of knowledge of these processes, their significance in biological systems, and their application in medicine are presented in subsequent sections of this chapter.
PL
W wyniku chemicznej modyfikacji słabo usieciowanego terpolimeru metakrylanu glicydylu (GMA), o stopniu funkcjonalizacji ok. 1,4 mmol/g, na drodze reakcji z etylenodiaminą (EDA), dietylenotriaminą (DETA) lub tris(2-aminoetylo)aminą (TAEA) otrzymano reaktywne żele z funkcjami poliaminowymi. Uzyskane żywice scharakteryzowano pod względem pęcznienia w wybranych rozpuszczalnikach organicznych oraz zdolności sorpcyjnych z rozpuszczalników organicznych wobec aldehydów aromatycznych: salicylowego, 3,5-di-f-butylosalicylowego i 3,5-dichlorosalicylowego oraz benzoesowego i 2-etoksybenzoesowego. Sorpcję aldehydów prowadzono z rozpuszczalników zapewniających zróżnicowane spęcznienie żywic, tj. z tetrahydro-furanu (THF), chlorku metylenu, metanolu oraz mieszaniny CH2C12:CH3OH (1:1, V:V). Stwierdzono, że szybkość chemicznego wiązania aldehydów nie może być kojarzona jedynie ze strukturą chemiczną aldehydu i wynikającym z niej powinowactwem w reakcji z I-rzędowymi grupami aminowymi, oraz z ilością grup NH2 w żywicy, lecz jest funkcją wielu różnych czynników, w tym także natury chemicznej rozpuszczalnika oraz wzajemnego powinowactwa rozpuszczalnik-żywica, decydującego o stopniu spęcznienia żywicy.
EN
Low crosslinked glycidyl methacrylate (GMA) terpolymers with a functionalization degree of 1.4 mmol/g have been chemically modified with ethylenediamine (EDA), diethylenetri-amine (DETA), or tris(2-aminoethyl) amine (TAEA) to obtain reactive gels with polyamine functional groups (Figs. 3-5). The varying swelling properties of the obtained resins in selected organic solvents -THF, methylene chloride, methanol and the mixture of CH2C12:CH3OH (1:1, V:V) were examined (Fig. 6). The sorption capacity of the aromatic aldehydes - salicylaldehyde, 3,5-di-ferf-butylsalicylaldehyde, 3,5-dichlorosalicylaldehyde (Figs. 7-16), benzaldehyde and 2-ethoxybenzaldehyde in these solvents determined (Table 1). The studies confirm that the rate of chemical bonding of the modified resins with aldehydes does not depend exclusively on the chemical structure of the aldehyde which is responsible for their affinity to primary amine groups and the amount of NH2 groups present in the resin (Figs. 1,2), but also on various factors among which are the chemical nature of the solvent and the solvent-resin interaction, on which the degree of resin swelling depends.
EN
The Suzuki-Miyaura coupling of 4- and 6-halosteroids affords good to excellent yields of potential aromatase inhibitors.While the reaction with 4- and 6-bromo derivatives is catalyzed by Pd(PPh3)2Cl2, the coupling with 6-chloro steroid (chlormadinone acetate) requires the use of Pd(dppb)Cl2 or Pd(dppf)Cl2. The palladium-catalyzed amination of bis(3-bromophenyl) ether of (5_)-cholane-3,24-diol with different polyamines leads to new macrocycles comprising one steroid and one polyamine fragments. Possibility of synthesis of macrocyclodimers containing two steroid and two polyamine fragments have been investigated.
EN
The synthesis of (ferrocenyl)-N-diphenylmethylaminomethane phosphonous acid ester with polyethylene glycols and the synthesis of its amides with polyamines in dichloromethane and in the presence of N,N_-dicyclohexylcarbodiimide (DCC) as condensing agent are presented.
PL
W wyniku prowadzonej w temp. 70-75°C w fazie stopionej poliaddycji trietylenotetraaminy (TETA) z 2-merkaptobenzotiazolem (MBT) otrzymano ciekłe, mało wrażliwe na wilgoć, mało toksyczne, o niewielkiej prężności par i słabym zapachu aminy, niekrzepnące nawet w temp. <15°C i dobrze mieszające się z żywicami epoksydowymi nowe addukty (TM) (tabela 1). Zastosowane do utwardzania żywic epoksydowych (w temp. 20-100°C) addukty te okazały się bardziej reaktywne niż TETA ze względu na katalityczny wpływ grup -SH obecnych w MBT. Żywice epoksydowe utwardzone adduktami typu TM charakteryzują się dobrymi właściwościami mechanicznymi i dielektrycznymi, odpornością chemiczną oraz odpornością cieplną (tabele 4-6). W fazie stopionej otrzymano również stałe addukty (MM) metylenodianiliny (MDA) z MBT o właściwościach przedstawionych w tabeli 2. Czas życia w temp. 55°C kompozycji epoksydowych zawierających addukty typu MM jest wyraźnie krótszy niż czas życia kompozycji z samą MDA. Kompozycje epoksydowe utwardzone adduktami MM wykazują lepsze właściwości mechaniczne i cieplne w porównaniu z kompozycjami utwardzanymi MDA (tabela 4).
EN
Polyaddition of triethylenetetraamine (TETA) to 2-mercaptobenzothiazole (MBT) carried out in the melt at 70-75°C gave novel adducts (TM) which were liquids of low toxicity, low volatility and faint amine-like odor, insensitive to moisture, infusible (<15°C) and well mis-cible with epoxy resins (Table 1). When used to cure (at 20-100°C) epoxy resins, the adducts proved to be more reactive than TETA, because of the catalytic effect of the -SH groups in MBT. The TM-cured epoxy resins exhibited satisfactory mechanical properties and good resistance to chemicals, heat and water (Tables 4-6). Crystalline adducts (MM), m.p. 78-84°C, of methylenedianiline (MDA) to MBT were also prepared (Table 2). At 55°C, the pot life of the MM-cured epoxy resin compositions was much shorter than that of the compositions with MDA only. The MM-cured compositions showed better mechanical and thermal properties as compared with those cured with MDA (Table 4). They can be used as adhesives, wet lay-up laminates.
EN
Computer analysis of potentiometric titration data was applied for determination of stability constants of Cd(II) and Hg(II) complexes in binary systems with polyamines (PA), nucleosides (Nuc) and nucleotides (NMP). For the systems of Hg(II) and PA an untypical increase in the complex stability with increasing ring size was observed and interpreted as the mercury preference to formation of linear complexes. Results of the potentiometric and 13CNMR studies for the complexes of both metal indicate the involvement of all donor nitrogen atoms of di- and triamines in the coordination, leading to formation of N2 and N3 type chromophores, respectively. Monodentate complexes of Hg(II) with Cyd are formed already at very low pH (complexes with Cd from pH of about 4). In the systems with AMP apart from nitrogen donor atoms, also the phosphate groups are involved in coordination. In the solid complexes of Cd(II) and Hg(II) with PA all donor atoms from the polyamines were found to be involved in the coordination and the presence of nitrate ions was established both in the inner and in the outer coordination spheres.
EN
34-membered macrocyclic hexaamine containing two independent N-3 donor sets forms homodinuclear transition metal complexes with cobalt(II), copper(II), and nickel(II). Titration experiments show that the homodinuclear complexes are formed exclusively without formation of mononuclear complexes. Displacements of anions within the copper(II) complexes occur easily upon addition of different anions to the CuCl2 complex. All new complexes are characterized by elemental analysis, IR and UV/VIS spectroscopy, and cyclic voltammetry. The dinuclear Cu(II) complex both in the solution and immobilized in Nafion layer on the electrode undergoes revesible l e reduction independently at each copper center and exhibits catalytic activity towards oxygen reduction.
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