Amino Phosphonic Acids

Phosphonic Acid Amino-phenyl-methan- E21e, 5725 [Nitron +... 

Ghelants and Precipitation Inhibitors vs Dispersants. Dispersants can inhibit crystal growth, but chelants, such as ethylenediaminetetraacetic acid [60-00-4] (EDTA), and pure precipitation inhibitors such as nitrilotris(methylene)tris-phosphonic acid [6419-19-8], commonly known as amino trismethylene phosphonic acid (ATMP), can be more effective under certain circumstances. Chelants can prevent scale by forming stoichiometric ring stmctures with polyvalent cations (such as calcium) to prevent interaction with anions (such as carbonate). Chelants interact... 

The substrate scope is limited, as electron-withdrawing groups (X = p-N02 or p-CF3) on the aromatic substituent are not tolerated. However, this route does provide valuable intermediates to unnatural a-amino phosphonic acid analogues and the sulfimine can readily be oxidized to the corresponding sulfonamide, thereby providing an activated aziridine for further manipulation, or it can easily be removed by treatment with a Grignard reagent. 

CN (4-Amino-1-hydroxybutylidene)bis[phosphonic acid] monosodium salt trihydrate acid... 

CN [l-[[[(2-chloroethyl)nitrosoamino]carbonyl]amino]ethyl]phosphonic acid diethyl ester... 

Other cyclizations at phosphorus have been observed when certain phosphinates were used in the acid-catalyzed Mannich reaction. As observed previously with various phosphonous acid derivatives, reaction of aliphatic phosphinic acids with primary amines favored the formation of 2 1 adducts (73). Thus, glycine and other a-amino acids reacted under the typical conditions with excess formaldehyde and alkyl phosphonous acids to give the bis-phosphinylmethyl adducts 125. 

Abbreviations N-methyl-D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA), L(+)-2 amino-3-phosphonopropionic acid (L-AP3), 6-cyano-7-nitroqninoxaline (CNQ5Q, 2,3-dihydroxy-6-nitro-7-sulfamyl-benzo-f-quinoxaline (NBQX), 3-(2-carboxypiperazin-4-yl)-propyl-l-phosphonic acid (CPP), 7 Chlorokynnreic... 

Sulfoxides without amino or carboxyl groups have also been resolved. Compound 3 was separated into enantiomers via salt formation between the phosphonic acid group and quinine . Separation of these diastereomeric salts was achieved by fractional crystallization from acetone. Upon passage through an acidic ion exchange column, each salt was converted to the free acid 3. Finally, the tetra-ammonium salt of each enantiomer of 3 was methylated with methyl iodide to give sulfoxide 4. The levorotatory enantiomer was shown to be completely optically pure by the use of chiral shift reagents and by comparison with a sample prepared by stereospecific synthesis (see Section II.B.l). The dextrorotatory enantiomer was found to be 70% optically pure. 

Scheme (17) illustrates the synthesis of the diphenyl ester (118) of (l-amino-2-propenyl)phosphonic acid (119), an... 

R=Me or COOEt) failed.2-Amino-4-phosphonobutanoic acid, the phosphonic acid analogue of glutamic acid, has been obtained in resolved forms by the action of papain, followed by aniline, on 2-benzoylamino-4-(diethoxyphosphinyl)butanoic acid when anilide occurs preferentially for the L- compound. Enantiomers of 4-amino-4-phosphonobutanoic acid were obtained by resolution... 

Scheme 21 summarizes further reactions leading to phosphonic acid analogues of amino acids. Treatment of the nitrone (138 R =Me or Pr ) with a dialkyl hydrogen phosphonate (best as the Li derivative which shows greater diastereoselectivity than the Na or K salts), and subsequent steps involving acidolysis of the oximino compound (139) lead to the free (ot-aminoalkyl)-phosphonic acids (140)(phosphonoalanine, phosphonova1ine). 

Several acyl derivatives of (aminomethyl)-and (1-aminoethyl)-phosphonic acids, in the latter case including [L-l-([L-alanyl]amino)ethyl]phosphonic acid (alafosfalin), have been prepared in their various diastereoisomeric forms and the... 

The heats of ionisation and neutralisation of amino and hydroxylic bis and tris phosphonic acids have been investigated.253 Calorimetry in combination with u.v. and n.m.r. spectroscopy uas used to study the adducts of fluoroalkyl carboxylic acids with diethyl phosphonate.254 The heats of formation of the t-butoxytriphenylphosphoranyl radical uas consistent with the phosphonium structure (92).255 There has been a thermal analysis of the adducts of phosphonic and phosphoric acids with... 

Another approach toward the preparation of analogues of natural amino acids has been reported using the salt of a phosphonous acid with an aldehyde and a substituted urea in acetyl chloride as a solvent/ facilitator.350 This approach provides analogues that bear a single acidic hydrogen at the "acid site," although the attached alkyl group at phosphorus renders the species sterically less like the natural compounds. 

Kowalik, J. Sawka-Dobrowolska, W., and Glowiak, T., Synthesis, molecular structure, and absolute configuration of an optically active (l-amino-2-phe-nylethyl)phosphonic acid monohydrate, J. Chem. Soc., Chem. Commun., 446, 1984. 

Huber, J.W. and Gilmore, W.R, Optically active a-amino-phosphonic acids from ureidophosphonates, Tetrahedron Lett., 3049, 1979. 

Redmore, D., N-Benzyl-a-amino phosphonic acids, J. Org. Chem., 43,996,1978. 

Research has also been conducted in which steryl phosphonic acid (SPA) was examined in place of benzyl arsonic acid (BAA), which was used in an operating plant in China [5], In this study, several collectors were examined, including sodium laurate, sodium dodecyl sulphate, amino acids, diphosphonic acid (SPA). It was discovered that SPA was the most effective and that aliphatic alcohol (i.e. octanol) was required to maintain the effectiveness of SPA. The use of emulsifier in the mixture was required to provide a suitable emulsion of the composite collector. 

The preparation of resolved species which are chiral at the germanium metal center have been reported (Equation (37), Table 2)44 47 as have species containing biologically important ligands48-52 including derivatives of a-amino-phosphonic acid.48-50... 

DIETHYL (R)-(-)-(1-AMINO-3-METHYLBUTYL)PHOSPHONATE PHOSPHONIC ACID, (1-AMINO-3-METHYLBUTYL)-, DIETHYL ESTER, (R)- ... 

Diethyl (R)-(-)-[1 -((N-(R)-(1 -phenyl-2-methoxyethyl)amino)-3-methylbutyl)]-phosphonate Phosphonic acid, [1-(2-methoxy-1-phenylethyl)amino]-3-methylbutyl]-, diethyl ester, [R-(R, R )]- (159117-09-6), 75, 20... 

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