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Polyamines synthetic

Pretreatment of rats with difluoromethylornithine (DFMO), an inhibitor of ornithine decarboxylase, prior to exposure to a tremorigenic dose of chlordecone, also resulted in inhibition of the tremor (Tilson et al. 1986b). DFMO was more effective if given 5 hours prior to the chlordecone than if given 24 hours prior to exposure. The DFMO was ineffective if given 19 hours after chlordecone exposure. These results suggest an interaction of the polyamine synthetic pathway with tremors produced by chlordecone. The mechanism of the interaction is unclear but may involve effects of polyamines on intracellular calcium homeostasis. Persons being treated with DFMO for cancer or protozoal infections would be likely to have reduced tremor severity after exposure to chlordecone. [Pg.146]

Synthetic Polymers. Examples of polymers in this class include acrylamide—acryHc polymers and their derivatives, polyamines and their derivatives, poly-(ethylene oxide), and allylamine polymers. [Pg.32]

PoIya.mines are condensation polymers containing nitrogen they are made by a variety of synthetic routes. Most of the commercial polyamines are made by reaction of epichlorohydrin with amines such as methylamine [25988-97-0] or dimethylamine [39660-17-8] (18,19). Branching can be increased by a dding small amounts of diamines such as ethylenediamine [42751-79-1]. A typical stmcture of this type of polyamine is stmcture (9). [Pg.33]

The polymer market ia the United States is dominated by synthetics with natural polymers constituting about one-eighth ia monetary terms (88). Of the synthetic polymers, most are based on acrylamide. A Hst of producers is as follows producers ia the left-hand column also produce polyamines and p oly qu atemarie s. [Pg.37]

Emulsifiers are incorporated in oil and synthetic mud formulations to maintain a stable emulsion of the internal brine phase. These materials include calcium and magnesium soaps of fatty acids and polyamines and amides and their mixtures (123,127). The specific chemistry of these additives depends on the nature of the continuous phase of the mud, ie, whether diesel oil, mineral oil, or a synthetic Hquid. Lime is added along with the fatty acid to form the... [Pg.182]

Last years the polymeric surface - active substances began to use as modifiers of organic reagent properties. In our work the behavior of synthetic polymers (polysulphonilpiperidinilmethylenhydroxide (PSPMH), polyvinylpyrrolidone (PVP), polyamines - polyguanidine and metacide) and natural polymers (starch, gelatin) for various molecular masses are investigated. [Pg.110]

Work also prepared a series of carbinolamines and polyamines without a quinoline nucleus but, in other respects, conforming in type and range of molecular weight, with quinoline compounds known to possess plasmocidal activity. As none of these were active, it seems clear that the quinoline nucleus in the cinchona alkaloids and in certain synthetic anti-malarials is a potent factor in the production of plasmocidal action. Later the same author made (1942) a series of lepidylamine derivatives of the form R. Q. CHj. NH[CH2] . NEtj, which were found to be inactive, in spite of their similarity to the active examples of the type R. Q. NH[CH2] . NEt2 prepared by Magidson and Rubtzow. Rubtzow (1939) has also shown that an isomeride of dihydroquinine (II) with the quinuclidine nucleus attached via the carbinol group at C in the quinoline nucleus was inactive in an infection of Plasmodium prcecox in finches. [Pg.475]

The macromonocyclic polyamines and the relevant compounds to be dealt with in this paper are shown in Chart I, along with abbreviation. For the synthetic procedures and physical properties of these compounds readers are requested to consult the references. [Pg.117]

In 1978 we described a synthetic methodology as a repeating-step principle , which led us to the first cascade molecules , today known as dendritic molecules [17]. We recognized then that a synthetic pathway, which allows consecutive repetition, implies the advantage of likewise reactants and reaction conditions and is suited for the building of more or less structure perfect highly branched molecules, particularly of polyamines (Fig. 4). [Pg.15]

In general, the acid-sorbing resins may be classified as high molecular weight polyamines or polyimines. Thus, the original Adams and Holmes material was a polymer of m-phenylenediamine. Cation Exchange materials include synthetic resins, such as sulfonated phenol-formaldehyde or polystyrene types, and sulfonated coal. Some manufacturers have a variety of sub-types which are considered superior for particular applications. [Pg.151]

In a similar manner, polymers with unsaturated chains or side chains can be converted to polyamines [66-69]. Conjugated diolefins usually undergo hydroformylation with low selectivities [70]. Mostly hydrogenation of at least one double bond occurs and mixtures of various saturated and unsaturated amines and diamines are obtained [71]. Similar to alkenes also alkynes may serve as unsaturated compounds in hydro aminomethylation reaction sequences. Although synthetically attractive, only a few investigations towards hydroformylation and hydroaminomethylation of alkynes in the presence of N-nuclcophilcs are known. Usually a preferred transformation to furanonic derivatives is observed under hydroformylation conditions [27]. [Pg.88]

Ethambutol is a synthetic agent and not related to any of the other tuberculostatics. Its mechanism of action is not well understood but in actively dividing mycobacteria it appears to be an inhibitor of mycobacterial RNA synthesis. It also has effects on bacterial phosphate metabolism and on polyamine synthesis. It is an bacteriostatic agent and its main function in combination therapy is to delay the occurrence of resistance, mainly against isoniazid and rifampicin. It is well absorbed after oral administration. It is widely distributed, except to the CNS. Protein binding is about 20-30%. It is mainly excreted unchanged in the bile and urine with an elimination half-life of 3 h. Ethambutol is concentrated in erythrocytes and thus provides a depot for continuous release. [Pg.418]

A) S. Custodero, ItalP 522944 (1955) CA 53, 3698 (1959) [Synthetic resin-base expls are prepd by incorporation of oxidizers into a liquid polymer which is then solidified by addn of a suitable catalyst. Thus, to 20% of a mixt contg 100 parts Araldit D and 9—lOps 951 (an alipahtic polyamine), 80% NaC103 was added with slow stirring to obtain a homogeneous paste. After it was shaped into the desired form by means of a press, it hardened on standing for... [Pg.424]

All BMI building blocks and maleimide-terminated oligomers discussed previously are synthesized from the corresponding polyamine precursor and maleic anhydride simply because of economic reasons. However, there are other synthetic methods available, for instance, the reaction of a functionalized monomaleimide with a polyfunctional monomer or oligomer. Such a functionalized monomaleimide is maleimido benzoic acid or its acid halide. These were used to synthesize maleimide-terminated polyamides (39, 40) or polyesters (41), respectively. [Pg.180]

The subject matter of this chapter will be subdivided into sections concerning template synthesis of the complexes structural and thermodynamic properties of the complexes with synthetic cyclic polyamines complexes with mixed-donor macrocycles reactivity of the complexes cryptates and complexes with phthalocyanines and porphyrins. [Pg.226]

Reduction of dihydropyrimidines by the use of excess sodium borohydride in methanol, at 60 °C, has been used as a route to substituted polyamines (equation 76). The reaction occurs in a stereocontrolled fashion and gives reasonable yields. These latter molecules are synthetic targets due to their potential in chemotherapy. [Pg.728]

A large number of drugs feature a heterocyclic component. Thus, the design, synthesis, and evaluation of heterocyclic libraries have rapidly become a major field of organic chemistry. Over the past decade, we have developed synthetic routes to a wide range of different heterocycles starting from resin-bound amino acids, short peptides, and polyamines. [Pg.503]

Thomas, T.J. and Bloomfield, V.A. (1984) Ionic and structural effects on the thermal helix-coil transition of DNA complexed with natural and synthetic polyamines. Biopolymers, 23, 1295-1306. [Pg.170]

Our group described a simple access to well-defined hyperbranched polyamines from hyperbranched PEI with different molecular weights, narrow molecular weight distributions, and an adjustable degree of branching [91]. According to this protocol fully branched analogs of polypropyleneimine (PPI) and polyamidoa-mine (PAMAM) dendrimers can be derived from hyperbranched PEI (Mw = 5,000, and 25,000 g mol-1) in a two-step synthetic process (Scheme 2). [Pg.103]


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See also in sourсe #XX -- [ Pg.163 ]




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