Amine phosphorylation reactions

The development of monoalkyl phosphate as a low skin irritating anionic surfactant is accented in a review with 30 references on monoalkyl phosphate salts, including surface-active properties, cutaneous effects, and applications to paste and liquid-type skin cleansers, and also phosphorylation reactions from the viewpoint of industrial production [26]. Amine salts of acrylate ester polymers, which are physiologically acceptable and useful as surfactants, are prepared by transesterification of alkyl acrylate polymers with 4-morpholinethanol or the alkanolamines and fatty alcohols or alkoxylated alkylphenols, and neutralizing with carboxylic or phosphoric acid. The polymer salt was used as an emulsifying agent for oils and waxes [70]. Preparation of pharmaceutical liposomes with surfactants derived from phosphoric acid is described in [279]. Lipid bilayer vesicles comprise an anionic or zwitterionic surfactant which when dispersed in H20 at a temperature above the phase transition temperature is in a micellar phase and a second lipid which is a single-chain fatty acid, fatty acid ester, or fatty alcohol which is in an emulsion phase, and cholesterol or a derivative. 

Full details on the phosphorylation of water and alcohols by 4-nitrophenyl dihydrogen phosphate and the NfC H ) - and N(CH3) -salts of its mono- and dianion have been published 146>. Phosphoryl group transfer from the monoanion and dianion is thought to proceed via the monomeric POf ion. Addition of the sterically unhindered amine quinuclidine to an acetonitrile solution containing the phosphate monoanion and tert-butanol produces t-butyl phosphate at a faster rate than does the addition of the more hindered diisopropylethylamine. This nucleophilic catalysis of the phosphorylation reaction is also explained by the intermediacy of the POf ion. 

The preparation of furyl phosphorodichioridate is based upon a method to prepare 2-chlorofuran (16% yield, Hormi, Nasman unpublished). Later the preparation was extended to a general method to prepare furyl esters from carboxylic acid chlorides lacking a-hydrogens and alkyl furyl carbonates from primary (other than methyl) and secondary alkyl chloroformates. Phosphoryl chloride was the only acid chloride except carbon analogues found to give a furyl ester by the amine-catalyzed reaction. 

In contrast, the 2-position of 2,4-dichloroquinazoline is more reactive than the 4-position for the attack by tertiary amines. The reaction of 2,4-dichloroquinazoline with A -substituted cyclic amines thus affords cyclic A,iV-disubstituted 4-chloroquinazolin-2-amines 9 and, in the case of A -methylpyrrolidine, the ring-opened derivative 10. The regioselectivity of this reaction is considered to be determined by the steric nature of 2,4-dichloroquinazoline and is in good accord with that of the reaction of quinazoline-2,4(l//,3//)-dione with A-substituted cyclic amines in combination with phosphoryl chloride (cf. p 121). 

Carbamates, like carbosulfan (66), have a similar mode of action, namely poisoning of the enzyme acetylcholinesterase, except that this is now achieved by carbamoylation rather than phosphorylation. Thiolocarbamates like (70) are prepared from the appropriate amines by reaction with phosgene (Scheme 13). 

A very clever three-phase test for the detection of metaphosphate intermediates in phosphoryl transfer reactions has been described by Rebek and coworkers (44). The basis of this test is the use of two polymers suspended in solution. The donor polymer contains a potential precursor to metaphosphate anion, e.g., an acyl phosphate or a phosphoramidate, and the recipient polymer contains an acceptor nucleophile, e.g., an amine. After reaction and physical separation of the polymers, the recipient polymer is analyzed for covalently bound phosphate. Since very few of the phosphoryl groups to be transferred will be on the surface of the donor polymer, detection of significant transfer to the recipient polymer provides evidence for a diffusible intermediate, i.e., free metaphosphate anion. Significant transfer did occur in dioxane or acetonitrile suspensions of the polymers, thereby providing evidence for an intermediate. However, this test for diffusible and, therefore, relatively stable metaphosphate anion is compromised by the choice of solvent. Both dioxane and acetonitrile can provide unshared electron pairs for the highly electrophilic metaphosphate anion such that the actual species that migrates from the donor polymer to the recipient polymer may be a complex between metaphosphate anion and the solvent. Such a role for solvent has been investigated stereochemically, the results of which will be described later in this section. 

Steroids possessing one or two isolated or conjugated double bonds are converted into their dihydrogen phosphates when brought into contact with (l-phenyl-l,2-dibromoethyl)phosphonic acid in the presence of ethyldiisopropyl-amine. The reactions presumably involve monomeric metaphosphate ion as the effective phosphorylating agent. ... 

Monoalkylation of primary amines. This reaction can be carried out in three steps. The primary amine (1) is phosphorylated under phase-transfer conditions to give a diethyl ester (2) of an N-alkylphosphoramidic acid (6, 42) this ester can... 

One of the disadvantages of traditional macroligands is a relatively poor utilization of their functional groups. Therefore, extensive studies are being carried out to find new types of macroligands (16). The most widely used methods for these purposes consist in the chemical modification of the carrier polymer surface (i.e., oxidation, chlorination, amination, phosphorylation, etc.). The difficulties vhich are encountered in doing so are diversity of the reaction routes and uncontrolled transformations both through the layer... 

The poly(amine-hydrazide)s can be prepared from the polycondensation of 9-[MA -di(4-carboxyphenyl)amino]anthracene with terephthalic dihydrazide and isophthaUc dihydrazide by the Yamazaki phosphorylation reaction. The poly(amine-hydrazide)s are readily soluble in many common organic solvents and can he solution cast into transparent films [48]. The materials can be thermally cyclodehydrated into the corresponding oxadiazole polymers in the range of 300-400 °C. An anthrylamine-based poly(amine-1,3,4-oxadiazole)s shows electrochromic characteristics with changing color from the pale yellow neutral form to the red in the range of 0.00 to -2.20 V. 

In order to cast further light on the mechanism underlying selective uncoupling , we here investigated in more detail to what extent inhibition of the phosphorylation reaction and a dissipation of A P may be involved in the effects of t-amines. A model for mechanism of action of t-amines is presented. 

Also interesting in the field of physiologically active substances are phosphorylated imidazoles 1640. These can be prepared from an isocyanide intermediate 1639 with primary amines, while reaction of the isocyanide with hydrazonic acid yields phosphorylated tetrazole 1641. The phosphorylated isocyanide 1639 is obtained by dehydration of the corresponding formamide 1637 with phosphorus pentachloride via an imine intermediate 1638 [1222]. 

A simpler nonphosgene process for the manufacture of isocyanates consists of the reaction of amines with carbon dioxide in the presence of an aprotic organic solvent and a nitrogeneous base. The corresponding ammonium carbamate is treated with a dehydrating agent. This concept has been apphed to the synthesis of aromatic and aUphatic isocyanates. The process rehes on the facile formation of amine—carbon dioxide salts using acid haUdes such as phosphoryl chloride [10025-87-3] and thionyl chloride [7719-09-7] (30). 

The biochemical basis for the toxicity of mercury and mercury compounds results from its ability to form covalent bonds readily with sulfur. Prior to reaction with sulfur, however, the mercury must be metabolized to the divalent cation. When the sulfur is in the form of a sulfhydryl (— SH) group, divalent mercury replaces the hydrogen atom to form mercaptides, X—Hg— SR and Hg(SR)2, where X is an electronegative radical and R is protein (36). Sulfhydryl compounds are called mercaptans because of their ability to capture mercury. Even in low concentrations divalent mercury is capable of inactivating sulfhydryl enzymes and thus causes interference with cellular metaboHsm and function (31—34). Mercury also combines with other ligands of physiological importance such as phosphoryl, carboxyl, amide, and amine groups. It is unclear whether these latter interactions contribute to its toxicity (31,36). 

An alternative method involves reaction of an a-acylaminoketone (12) with a primary amine and subsequent ring closure of the resultant Schiff s base (13) with phosphoryl chloride. This enables the introduction of a 1-substituent as in (14) to be carried out efficiently, and if the amine were replaced with a monosubstituted hydrazine, the imidazole derivative (IS) resulted (78LA1916). 

The procedure described is essentially that of Shioiri and Yamada. Diphenyl phosphorazidate is a useful and versatile reagent in organic synthesis. It has been used for racemlzatlon-free peptide syntheses, thiol ester synthesis, a modified Curtius reaction, an esterification of a-substituted carboxylic acld, formation of diketoplperazines, alkyl azide synthesis, phosphorylation of alcohols and amines,and polymerization of amino acids and peptides. - Furthermore, diphenyl phosphorazidate acts as a nitrene source and as a 1,3-dipole.An example in the ring contraction of cyclic ketones to form cycloalkanecarboxylic acids is presented in the next procedure, this volume. 

Phosphatidylethanolamine synthesis begins with phosphorylation of ethanol-amine to form phosphoethanolamine (Figure 25.19). The next reaction involves transfer of a cytidylyl group from CTP to form CDP-ethanolamine and pyrophosphate. As always, PP, hydrolysis drives this reaction forward. A specific phosphoethanolamine transferase then links phosphoethanolamine to the diacylglycerol backbone. Biosynthesis of phosphatidylcholine is entirely analogous because animals synthesize it directly. All of the choline utilized in this pathway must be acquired from the diet. Yeast, certain bacteria, and animal livers, however, can convert phosphatidylethanolamine to phosphatidylcholine by methylation reactions involving S-adenosylmethionine (see Chapter 26). 

The ureas, e.g. 28 (R = NMe2), derived from the corresponding 2-(l-arylviny )benzylamines by reaction with (dimethylamino)carbamoyl chloride (Me2NCOCl) in the presence of triethyl-amine, undergo cyclization in refluxing phosphoryl chloride to the 5-aryl-3-(dimethylamino)-l//-2-benzazepin-3-amines. e.g. 29a.84 Prepared similarly are the 3-(4-methylpiperazin-l-yl) compound 29b and the 3-methyl derivative 29c from the corresponding urea and amide, respectively. 

PreUminary studies on the racemic reaction of protected imines with ni-tromethane showed that the thiourea and the amine mutually weakened their reactivities. However, the bifunctional amino-thiourea led to good results. Enantioselectivity of the adduct depended on the protecting group, P(0)Ph2 affording the best results (76% ee). Then, other aromatic imines substrates were successfully phosphorylated with good to high enantioselec-tivities (63-76% ee). 

Product Acceptors. Many enzyme assays use acceptors, as for instance 2-ethylaminoethanol and other aminated alcohols iihich act as acceptors for the phosphoryl product of the reaction catalyzed by alkaline phosphatase (25) (Fig. 4). Hydroxylamine can act as an acceptor for the hydroxyacetone produced by eno-lase and semicarbazide can act as an acceptor for the pyruvate produced by LD. It is necessary to optimize the concentration of such an acceptor before using it routinely as often what may be a theoretically desirable acceptor is in practice superfluous. 

No details are given for scheme A. Presumably one could use the phosphoryl chloride instead of the fluoride. Scheme B, in which ethyl chloride is formed, was run in boiling xylene using equimolar quantities of the reactants. Michaelis (33) has partially described the preparation of starting materials from secondary amines with phosphorus oxychloride and also ethyl dichlorophosphate. Schrader (38) obtained alkyl and amido fluophosphates by reaction of the corresponding chlorophosphates with sodium fluoride in aqueous or alcoholic solution. 

Phosphoryl-substituted diazo compounds of general type 4 have recently been synthesized by amine diazotization, Bamford-Stevens reaction, and diazo group... 

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