Polyamino compounds

Of particular interest to soil chemists are polycarbonyl and polyamino compounds that can form associations with metals. A multiplicity of polycarbonyl and polyamino compounds is extruded by plant roots, so solutions of these or similar compounds are used to mimic the extracting capabilities of plant roots. However, it is not possible to completely duplicate the extracting activities of roots. 

Polycarbonyl and polyamino compounds include chelates, which are manmade compounds, and siderophores, which are biologically derived and more specialized. They can help dissolve inorganic ions, keep ions in one specific ionic state, and maintain them in biologically available forms. Because of their ability to bring ions into solution, they are often used to extract specific ions in specific forms from soil. Cationic micronutrients, particularly iron and zinc, are often applied in chelated form as a foliar spray to alleviate nutrient deficiencies. This is particularly true of plants growing in basic soil and is done even when plants do not show micronutrient deficiencies. Typically, both foliar and soil applications are effective in this regard. 

Two examples of polycarbonyl and polyamino compounds are shown in Figure 5.7. Ethylenediaminetetraacetic add (EDTA) is a synthetic ligand. The other, a siderophore, is biologically derived. Other polycyclic structures that coordinate with iron are also common. 

The lower members of the homologous series of 1. Alcohols 2. Aldehydes 3. Ketones 4. Acids 5. Esters 6. Phenols 7. Anhydrides 8. Amines 9. Nitriles 10. Polyhydroxy phenols 1. Polybasic acids and hydro-oxy acids. 2. Glycols, poly-hydric alcohols, polyhydroxy aldehydes and ketones (sugars) 3. Some amides, ammo acids, di-and polyamino compounds, amino alcohols 4. Sulphonic acids 5. Sulphinic acids 6. Salts 1. Acids 2. Phenols 3. Imides 4. Some primary and secondary nitro compounds oximes 5. Mercaptans and thiophenols 6. Sulphonic acids, sulphinic acids, sulphuric acids, and sul-phonamides 7. Some diketones and (3-keto esters 1. Primary amines 2. Secondary aliphatic and aryl-alkyl amines 3. Aliphatic and some aryl-alkyl tertiary amines 4. Hydrazines 1. Unsaturated hydrocarbons 2. Some poly-alkylated aromatic hydrocarbons 3. Alcohols 4. Aldehydes 5. Ketones 6. Esters 7. Anhydrides 8. Ethers and acetals 9. Lactones 10. Acyl halides 1. Saturated aliphatic hydrocarbons Cyclic paraffin hydrocarbons 3. Aromatic hydrocarbons 4. Halogen derivatives of 1, 2 and 3 5. Diaryl ethers 1. Nitro compounds (tertiary) 2. Amides and derivatives of aldehydes and ketones 3. Nitriles 4. Negatively substituted amines 5. Nitroso, azo, hy-drazo, and other intermediate reduction products of nitro com-pounds 6. Sulphones, sul-phonamides of secondary amines, sulphides, sulphates and other Sulphur compounds... 

Polyhydroxy- phenols. amino acids, di- and polyamino compounds, amino alcohols. Sulphonic acids. Sulphinic acids. Salts. sulphinic acids, aminosulphonic acids and sulphonamides. Some diketones and /3-keto esters. Ethers and acetals. Lactones. Acyl halides. Diaryl ethers. intermediate reduction products of nitro compounds. Sulphones, sulphonamides of secondary amines, sulphides, sulphates and other sulphur compounds. 

Selective reactions of amino groups in polyamino compounds (particularly those in heterocyclic polyamines) by metal-chelated or -mediated methods 01T4801. 

A series of related polyamino compounds, which are derived in part from arginine, are present in all cells in relatively high, often millimolar, concentrations.The content of polyamines in cells tends... 

Anion exchange resins are resinous organic bases that can be activated for use in either of two ways (1) acid removal and (2) anion exchange. Anion exchange resins are generally polyamino compounds, such as the type obtained from the reaction between phenol, ethylenediamine, and formaldehyde. 

Amino-alcohols Polyamino-compounds Sulphonic acids Salts of amines or urea Salts of alkali metals Ammonium salts of organic acids... 

Polyamino acids are easy to prepare by nucleophUe-initiated polymerisation of amino acid JV-carboxyanhydrides. Polymers such as poly-(L)-leucine act as robust catalysts for the epoxi-dation of a wide range of electron-poor alkenes, such as y-substituted a,Ji-unsaturated ketones. The optically active epoxides so formed may be transformed into heterocyclic compounds, polyhydroxylated materials and biologically active compounds such as dUtiazem and taxol side chain. 

Many of the enone substrates used in polyamino acid-catalysed epoxidation reactions can be made via a simple aldol condensation, which leads directly to the desired enone after in situ dehydration. Enones that cannot be synthesised by the above route may often be synthesised using standard Wittig chemistry, (Scheme 6). The above methods of substrate synthesis provide compounds with a variety of groups R and enabling the incorporation of both aliphatic and aromatic moieties into the enone structure. 

Interaction of the solute with radicals from the water is the first of a sequence of reactions which finally leads to stable products. Kinetic studies of the type cited give valuable information about the primary radical species and their relative reaction rates with molecules of different types. When sufficient data have been accumulated, it should be possible to predict the course of radiolysis in complex molecules. From the nature and yields of the products and by observing the effects on them of various factors such as concentration, pH, 02, and specific radical scavengers, it is often possible to speculate about the mechanisms by which products are formed. More often than not, this is a difficult problem because the products, even from relatively simple compounds, prove to be complex. Furthermore, it is often possible to produce more than one mechanism to fit the experimental data. The proteins are particularly difficult because of their complex structures. They contain approximately 20 different amino acids with an average of more than three carbon atoms in the side chains, which vary considerably in their structure hence, the possible number of products is large. For this reason, model compounds such as peptides and polyamino acids have been studied because they contain the peptide linkage but are free from the complications which arise from the diversity of the amino acid residues in a protein. A further practical difficulty which applies to chem-... 

We have carried out a computational and experimental study on the "random coil" conformation of poly-L-Tyr to answer the question about the local order in the "random coil" conformation which had been addressed before by researchers in a number of fields [39,40]. This study was made possible by our successful application of the DECO model (cf. Section 3) to interpret VCD spectra of model compounds. Our efforts to deduce a structure for the "random coil conformation of (homo)-polyamino acids was prompted by the observation by us and others [41] that the "random coil" in systems (such as poly-L-Tyr) produces VCD features which are nearly equal in magnitude, and opposite in sign, to those produced by the a-helical conformation (cf. Figure... 

Most of the thermodynamic studies have been performed in aqueous solutions as the cycles and their derivatives are first of all ligands for complexation of water-soluble metal ions. Numerous compounds have been studied and, therefore, only a general overview of trends is given. More information can be find in commercial databases such as NIST Standard Reference Database 46 (Critically Selected Stability Constants of Metal Complexes) or The IUPAC Stability Constants Database (SC-Database) or in reviews <2005PAC1445> (critically evaluated data for DOTA 3 and TETA 4), <1999CCR97> (protonation constants of polyamines) and <2000CCR309> (protonation constants of polyamino-polycarboxylic acids). Overall basicity of the ligands is mostly the main determinant for values of stability constants of metal complexes. 

A dinuclear compound, (Me2N)3P=N-P(=NH)(NMe2)2, with a high nitrogen phosphorus ratio is the first member of a series of strongly basic, branched polyamino-imino phosphazenes (Scheme 43). ... 

Another important asymmetric epoxidation of a conjugated systems is the reaction of alkenes with polyleucine, DBU and urea H2O2, giving an epoxy-carbonyl compound with good enantioselectivity. The hydroperoxide anion epoxidation of conjugated carbonyl compounds with a polyamino acid, such as poly-L-alanine or poly-L-leucine is known as the Julia—Colonna epoxidation Epoxidation of conjugated ketones to give nonracemic epoxy-ketones was done with aq. NaOCl and a Cinchona alkaloid derivative as catalyst. A triphasic phase-transfer catalysis protocol has also been developed. p-Peptides have been used as catalysts in this reaction. ... 

R48 A. Bianchi, L. Calabi, F. Corana, S. Fontana, P. Losi, A. Maiocchi, L. Paleari and B. Valtancoli, Thermodynamic and Stmctural Properties of Gd(III) Complexes with Polyamino-Polycarboxylic Ligands Basic Compounds for the Development of MRI Contrast Agents , p. 309... 

Until recently, little success had been achieved in developing a highly enantioselective version of the Darzens reaction. Several investigations of chiral phase-transfer catalysts for this condensation, in which low or modest asymmetric induction is obtained, have been reported. These include the use of N-alky -N-methylephedrinium halides, the quinine-derived salt (120), and polyamino acids. A related study has examined the use of achiral phase-transfer catalysts in the condensations of carbonyl compounds and the asymmetric chloromethylsulfonate ester (121). The same group of researchers subsequently reported similar studies employing the sulfonamides (122)-(124). ... 

To explain the catalytic mechanism of the alkylene oxide polymerisation with phosphazenium compounds, several considerations concerning the peralkylated polyamino-phosphazenes should be made. 

It is important to have simple and inexpensive methods for preparation of the diamine starting materials needed for cyclization to form the diaza-crown compounds. Many of the oligoethylene (or oligopropylene) polyamines and their Y-methyl and Y-ethyl analogs can be purchased. We present here some of the methods that have been used to prepare the diamino and polyamino aliphatic ethers that are not available. 

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