Lipid amines

Primary ( ) amines e.g. alkyl amines [1—3] lipid amines [4] a, co-diamines [5, 6] polyamines [6] alkanol amines [7] subst. anilines [8] aminoglycoside antibiotics [9, 10] biogenic amines [11] hydrazines... 

Linearity, improvement of calibration curves by derivatization 56 Linoleic acid 73 Linolenic acid 73 Linuron 74,108 Lipid amines 284... 

N.m.r. spectroscopy T.l.c.-m.s. analysis of oligosaccharides coupled to a lipid amine (neoglycolipids) H n.m.r. spectrum in D20 after exchange of free protons with deuterium Experiments conducted at 295 K, with acetone as the internal standard (set at 2.225 p.p.m. from 4,4-dimethyl-4-silapentane-1-sulfonate) Results compared, to within 0.005 p.p.m. (laboratory-to-la-boratory variation) of data in the literature Conformational studies by n.O.e. experiments Natural-abundance-13C analysis Chemical-shift assignment by 2D H- H and H-13C n.m.r. spectroscopy... 

The wide variety of known oxidases reflects the complexities of the different substrate classes such as carbohydrates, amino acids, lipids, amines, metabolites, alcohols, acids, and other chiral building blocks. An overview of synthetic applications of oxidases is given in Figure 20.3. 

A considerable variety of nitrogen-containing compounds, other than proteins and nucleic acids, occur in plants and animals. In plants, free amino acids are usually present those in greatest amount include glutamic acid, aspartic acid, alanine, serine, glycine and proline. Other compounds are nitrogenous lipids, amines, amides, purines, pyrimidines, nitrates and alkaloids. In addition, most members of the vitamin B complex contain nitrogen in their structure. 

With this precursor in hand, Fmoc removal and acetylation of the resulting Af-terminus amine, followed by hydrogenolysis of the benzyl ester at the C-terminus, and subsequent cleavage of the acetate and benzoate esters within the carbohydrates afforded the fully deprotected glycopeptide 57. Finally, the lipid amine PamgCysSer 35 was coupled to the acid terminus of the heptapeptide (HOAt/HATU) to afford the synthetic antigenic construct 58, thus completing the total synthesis of a mucin-like cluster of fully synthetic Le epitopes (Scheme 13). 

As regards the synthesis of esters as potential prodrugs, five 5 -0-esters of 2, 3 -dideoxyadenosine have been prepared, and their bioavailability assessed in rats,292 and AZT has been linked at 0-5 to various lipidic amine acid oligomers. 38 T he antiviral agent 9-(P-D-arabinofuranosyl)-6-methoxypurine has been converted into 5 -<2-acyl derivatives,293 and into di-and triesters,294 and esters of 2 -deoxy-2 -methylenecytosine, an antitumour agent, have also been described.295... 

A rather limited collection of simple precursor molecules is sufficient to provide for the biosynthesis of virtually any cellular constituent, be it protein, nucleic acid, lipid, or polysaccharide. All of these substances are constructed from appropriate building blocks via the pathways of anabolism. In turn, the building blocks (amino acids, nucleotides, sugars, and fatty acids) can be generated from metabolites in the cell. For example, amino acids can be formed by amination of the corresponding a-keto acid carbon skeletons, and pyruvate can be converted to hexoses for polysaccharide biosynthesis. 

Following the action of extraordinary stimulants (hypoxic hypoxia, hypoxia + hyperoxia, hypodynamia + hyperthermia), animals demonstrate an accumulation of malonic dialdehyde with a simultaneous fall of antiradical activity of the liver tissue. A preliminary introduction to rats of acetylene amine 3,4,5-tris(morpho-linopropynyl)-l-methylpyrazole 103 and also of tocopherol antioxidant and gutumine antihypoxant averts activation of the lipid peroxidation processes. The inhibition of peroxidation with this agent is mediated by stabilization of ly-zosomal and mitochondrial membranes. Unsaturated amines prevent destruction of the organelle membranes provoked by UV irradiation and incubation at 37°C (pH4.7)(78MIl). 

The ending caine stems from cocaine, the first clinically employed local anaesthetic. Procaine and tetracaine are ester-linked substances, the others are amides. Amide bonded local anaesthetics usually contain two i s in their name, ester-bonded only one. In the structure drawings, the lipophilic portion of the molecule is depicted at the left, the amine at the right. The asterisk marks the chiral centre of the stereoisomeric drugs. Lipid solubility is given as the logarithm of the water octanol partition coefficient, log(P). 

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. 

Lipases are the enzymes for which a number of examples of a promiscuous activity have been reported. Thus, in addition to their original activity comprising hydrolysis of lipids and, generally, catalysis of the hydrolysis or formation of carboxylic esters [107], lipases have been found to catalyze not only the carbon-nitrogen bond hydrolysis/formation (in this case, acting as proteases) but also the carbon-carbon bond-forming reactions. The first example of a lipase-catalyzed Michael addition to 2-(trifluoromethyl)propenoic acid was described as early as in 1986 [108]. Michael addition of secondary amines to acrylonitrile is up to 100-fold faster in the presence of various preparations of the hpase from Candida antariica (CAL-B) than in the absence of a biocatalyst (Scheme 5.20) [109]. 

Antioxidant free radicals (A H) produced in this way are relatively stable, but they may react with another lipid free radical to form a quinone [15.3] and [15.4]. Quinones can react with amine or thiol groups of proteins, forming polymerisable yellow or red coloured compounds (Pokorny, 1987). Antioxidant free radicals may also react with either another antioxidant free radical or a lipid free radical, forming dimers [15.5] or copolymers [15.6] and [15.7], respectively. Oligomeric or condensated products of antioxidant free radicals usually possess moderate antioxidant activities too (Pokorny et al, 1974) ... 

BRITT c, GOMAA E A, GRAY j I and BOOREN A M (1998) Influence of cherry tissue on lipid oxidation and heterocyclic aromatic amine formation in groimd beef patties, JAgric Food Chem, 46, 4891-7. 

The mechanism of NPYR formation has been studied by Coleman (37) and Bharucha et al. ( ). Coleman (37) reported that the requirement for a high temperature, the inhibitory effects of water and antioxidants, and the catalytic effect of a lipid hydroperoxide are consistent with the involvement of a free radical in the formation of NPYR. Similarly, Bharucha et al. (29) suggested that, since both NPYR and NDMA increase substantially towards the end of the frying process, N-nitros-amine formation during frying of bacon occurs essentially, if not entirely, in the fat phase after the bulk of the water is removed and therefore by a radical rather than an ionic mechanism. These authors speculated that, during the frying of... 

Interaction of lipid oxidation products and amino compounds. Amino acids and primary amines may be involved in other reactions which could lead to the formation of compounds having the potential to undergo N-nitrosation. Malonaldehyde, produced as a result of oxidation of lipids, particularly polyunsaturated fatty acids, has been shown to react with amino acids to produce... 

Indeed, given an improperly designed or understood system, a blocking agent, like ascorbic acid, could be catalytic toward nitrosamine formation. For example, if the source of nitrosatlng agent is nitrite ion and the susceptible amine is in the lipid phase, conceivably ascorbic acid could cause the rapid reduction of nitrite ion to nitric oxide which could migrate to the lipid phase. Subsequent oxidation of NO to NO in the lipid phase could cause nitrosation. 

The common denominator of all these CP-channel blockers (Fig. 2) is their acidic function (usually carboxylate), the secondary amine with a certain spacing to the acidic group, a nitro substitution at a certain distance from the carboxylate group, and the apolar groups such as the phenyl-propyl-residue. We have suggested that the interaction with the CP-channel requires all of these interaction sites, and that even the apolar moiety of the blocker molecule reacts with the channel protein rather than with the membrane lipid [70]. 

Sphingolipids (ceramids, sphingomyelin, cerebrosides, sulfatides, gangliosides) and lipids with secondary amines produce blue spots on a white backgound (CAUTION benzidine is a carcinogen)... 

Ethanol and choline glycerolipids were isolated from calf brain and beef heart lipids by PTLC using silica gel H plates. Pure ethanol amine and choline plasmalogens were obtained with a yield of 80% [74]. Four phosphohpid components in the purple membrane (Bacteriorhodopsin) of Halobacterium halobium were isolated and identified by PTLC. Separated phosphohpids were add-hydrolyzed and further analyzed by GC. Silica gel G pates were used to fractionate alkylglycerol according to the number of carbon atoms in the aliphatic moiety [24]. Sterol esters, wax esters, free sterols, and polar lipids in dogskin hpids were separated by PTLC. The fatty acid composition of each group was determined by GC. 

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