Polyamines naturally occurring

Polyamine (Section 22.4) A compound that contains many amino groups. The term is usually applied to a group of naturally occurring substances, including spermine, spermidine, and putrescine, that are believed to be involved in cell differentiation and proliferation. 

Bichrach, U. (ed.) Function of Naturally Occurring Polyamines, Academic Press, New York and London 1973... 

Inward Rectifier K+ Channels. Figure 6 Spermine (Amino-propyl-amino-butyl-amino-propyl amine) is a long linear naturally occurring polyamine containing four nearly equally spaced positively charged (at normal pH) amines. Although 16 A long, the molecule is only about 3 A wide, similar to a dehydrated potassium ion. 

In addition to the glutamate and glycine sites on the NMDA receptor, there also exist polyamine sites which are activated by the naturally occurring polyamines spermine and spermidine. Specific divalent cation sites are also associated with the NMDA receptor, namely the voltage-dependent magnesium site and the inhibitory zinc site. In addition to the excitatory amino acids, the natural metabolite of brain tryptophan, quinolinic acid, can also act as an agonist of the NMDA receptor and may contribute to nerve cell death at high concentrations. 

The skeleton types are shown in (50)-(61). Symmetrical linear tetramines are normally synthesized by condensation of the appropriate centrally bridging a,o>-dihalide with excess of two moles of the diamine in ethanol. The addition of an inorganic base (NaOH or KOH) is usually required.739 740 Spermine (56) is naturally occurring and most of these polyamines are commerically available. 

The naturally occurring polyamine 3,3,3,3-pent (caldopentamine) has recently been isolated from high-temperature resistant bacteria (Thermus thermophilus).875... 

Bachrach, V. "Function of Naturally Occurring Polyamines", Academic Press, New York, 1973. 

Chronologically, this is the second family of cationic lipids that were employed for gene delivery. The pioneering work was presented by Behr et al. (1989), who had proposed to take advantage of DNA condensing property of a naturally occurring polyamine, such as spermine. Indeed, during cell division,... 

Of the common alkyl polyamines, ethylenediamine is the most notable because of its widespread use and toxicity. Although it has a toxicity rating of only three, it can be very damaging to the eyes and is a strong skin sensitizer. The dihydrochloride and dihydroiodide salts have some uses as human and veterinary pharmaceuticals. The former is administered to acidify urine, and the latter as an iodine source. Putrescine is a notoriously odorous naturally occurring substance produced by bacteria in decaying flesh. 

Finally there is a reaction of a N-substituted /3-lactam which had been used several times in the syntheses of natural occurring polyamine alkaloids [70] the /3-lactam VI/46 reacts on heating with 2-methoxypyrroline VI/56 [71] to form... 

V. Catalog of Naturally Occurring Diamine and Polyamine Alkaloids. 150... 

The naturally occurring di- and polyamine alkaloids are listed in the tables of Section V. At present, nearly 100 compounds have been reported. They were isolated from 56 genera in 30 plant and animal families. Some of the plants contain all three kinds of alkaloids (putrescine, spermidine, and spermine), e.g., Ananas comosus Merill. (Bromeliaceae). Intensive investigations of alkaloids were performed in some genera, e.g., Aphelandra, Chaenorhinum, Equisetum, Maytenus. The reasons were commercial availability and pharmacological interest (Maytenus). 

In contrast to extracts obtained from nature, which usually consist of a mixture of substances and are available only in very limited amounts, synthetic model systems have the advantages of controlled purity and good availability. Such systems enable the scientist to vary reaction parameters in a systematic fashion and to adjust individual functions to analyze their influence on the system. However, model systems should be as close as possible to the natural system. Therefore, we have undertaken a study to elucidate the chemical behavior of polyamine-silica systems, including not only polyamines which can be purchased, but also polyamines specifically synthesized, with structures as close as possible to the naturally occurring ones [11], Here, we report on investigations on the kinetics of silica condensation in the presence of various polyamines... 

Rennert et al.56 reported that naturally occurring polyamines spermidine (15) and spermine (16) inhibited ADP-induced, but not epinephrine-induced platelet aggregation. This inhibition was related to increases in these polyamines in leukemia, psoriasis, etc., and to increases in bleeding times. Synthetic diamines and polyamines have been reported previously to affect platelet aggregation.57... 

Niitsu, M., Samejima, K., Matsuzaki, S., and Hamana, K., Systematic analysis of naturally occurring linear and branched polyamines by gas chromatography and gas chromatography-mass spectrometry, J. Chromatogr., 641, 115-123, 1993. 

Of the potential Quadridentate Ligands shown in (178 192), Spermine (182) is a naturally occurring polyamine... 

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