SYNTHESIS OF L-α-PHOSPHATIDYL-(α-METHYL)CHOLINES

1967 ◽  
Vol 45 (2) ◽  
pp. 309-316 ◽  
Author(s):  
Erich Baer ◽  
Bimal C. Pal
Keyword(s):  
Phosphatidic Acid ◽  
Phenyl Group ◽  
Iodide Ion ◽  
Catalytic Hydrogenolysis

The synthesis of a new group of phospholipids, L-α-phosphatidyl-DL-(α-methyl)cholines is reported. Three homologous members of this group were prepared by phosphorylating D-α,β-dimyristin, D-α,β-dipalmitin and D-α,β-distearin, respectively, with phenylphosphoryl dichloride and pyridine, esterifying the resulting phenyl esters of the L-α-phosphatidic acid monochlorides with DL-(α-methyl)choline iodide, replacing the iodide ion of the L-α-phosphatidyl-DL-(α-methyl)choline phenyl esters by acetate ion, and removing the phenyl group by catalytic hydrogenolysis.

Synthesis of Diphytanyl Ether Analogues of Phosphatidic Acid and Cytidine Diphosphate Diglyceride

1971 ◽  
Vol 49 (3) ◽  
pp. 275-281 ◽  
Author(s):  
M. Kates ◽  
C. E. Park ◽  
B. Palameta ◽  
C. N. Joo
Keyword(s):  
Chemical Synthesis ◽  
Phosphatidic Acid ◽  
Physical Properties ◽  
Acid Hydrolysis ◽  
Anhydrous Benzene ◽  
Catalytic Hydrogenolysis ◽  
Cytidine Monophosphate ◽  
Cytidine Diphosphate

The chemical synthesis of 2,3-di-O-phytanyl-sn-1-glycerophosphate was carried out in two ways: (a) by phosphorylation of 2,3-diphytanyl-sn-glycerol with diphenylphosphoryl chloride in pyridine, followed by catalytic hydrogenolysis of the phenyl groups; and (b) by condensation of 1-iodo-2,3-di-O-phytanyl-sn-glycerol with silver di-p-nitrobenzyl phosphate in anhydrous benzene, followed by catalytic hydrogenolysis of the p-nitrobenzyl groups. The free diether phosphatidic acid obtained was converted to the dipotassium and disodium salts. The diether phosphatidic acid was also converted to the diether analogue of cytidine diphosphate diglyceride by condensation with cytidine monophosphate morpholidate in pyridine. The physical properties of these diether analogues are described, as well as their stabilities towards acid hydrolysis.

Chemical synthesis of sn-3-phosphatidyl sulfocholine, a sulfonium analog of lecithin

1979 ◽  
Vol 57 (6) ◽  
pp. 595-604 ◽  
Author(s):  
Paul-Alain Tremblay ◽  
Morris Kates
Keyword(s):  
Mass Spectrometry ◽  
Nuclear Magnetic Resonance ◽  
Chemical Synthesis ◽  
Optical Rotation ◽  
Phenyl Group ◽  
Elemental Analyses ◽  
Catalytic Hydrogenolysis ◽  
Nuclear Magnetic Resonance Spectrometry ◽  
Magnetic Resonance Spectrometry ◽  
Layer Chromatography

A sulfonium analog of lecithin has been reported to replace the ubiquitous phosphatidyl choline in a non-photosynthetic diatom, Nitzschia alba. The structure of this sulfonium analog has now been established by chemical synthesis using the following methods: (i) condensation of sn-3-phosphatidic acid (dimyristoyl-, dipalmitoyl-, distearoyl-, and dioleoyl-) with sulfocholine chloride in the presence of triisopropylbenzenesulfonylchloride in chloroform–pyridine (9:1); and (ii) phosphorylation of 1,2-dipalmitoyl-sn-glycerol with monophenylphosphoryl-dichloridate followed by a reaction with sulfocholine in the presence of pyridine and finally removal of the blocking phenyl group by catalytic hydrogenolysis. The desired synthetic products were obtained in overall yields of 50–70% and 11% for methods (i) and (ii), respectively, and were characterized by elemental analyses; infrared spectroscopy, nuclear magnetic resonance spectrometry, and mass spectrometry; optical rotation; and thin-layer chromatography mobilities. Comparison of the synthetic analogs with the natural sulfolecithin showed them to be identical, except for the nature of the fatty acid chains, thus establishing the natural product as sn-3-phosphatidyl sulfocholine.

Interaction of Vasopressin with Human Blood Platelets: Dependency on Mg2+

1986 ◽  
Vol 56 (03) ◽  
pp. 260-262 ◽  
Author(s):  
Isabella Roos ◽  
Fabrizia Ferracin ◽  
Alfred Pletscher
Keyword(s):  
Phosphatidic Acid ◽  
Human Blood ◽  
Arginine Vasopressin ◽  
Specific Binding ◽  
Blood Platelets ◽  
Bivalent Cations ◽  
Platelet Membranes ◽  
Maximal Rise ◽  
Human Blood Platelets ◽  
Stimulation Of

SummaryArginine-vasopressin (AVP) in the presence of Mg2+ but not in the absence of bivalent cations led to accumulation of [32P]-phosphatidic acid ([32P]-PA) in human blood platelets. Mg2+ also enhanced the specific binding of [3H]-AVP to intact platelets. The concentrations of the cation which enabled AVP to cause half maximal rise of [32P]-PA and those inducing half maximal [3H]-AVP-binding were of the same order. It is concluded that the stimulation of phosphatidyl inositide breakdown by AVP in presence of Mg2+ is at least partially due to a Mg2+-induced enhancement of specific AVP-binding to the platelet membranes.

Enhancement of the Release Reaction Not Accompanied with Enhanced Phosphatidylinositol Turnover in the Reserpinized Rabbit Blood Platelets

1983 ◽  
Vol 50 (02) ◽  
pp. 595-600 ◽  
Author(s):  
Y Watanabe ◽  
M Soda ◽  
N Fukamachi ◽  
B Kobayashi
Keyword(s):  
Phosphatidic Acid ◽  
Blood Platelets ◽  
Specific Protein ◽  
The Other ◽  
Release Reaction ◽  
Rabbit Blood ◽  
Phosphatidylinositol Turnover ◽  
Activated State ◽  
32P Incorporation ◽  
Platelet Release

SummaryThrombin-induced platelet release reaction examined with secretion of calcium and N-acetylglucosaminidase was significantly enhanced in the platelets from reserpine-treated rabbits as compared with the control. On the other hand, 32P-incorporation into phosphatidic acid was suppressed in the reserpinized platelets in activated state. Thrombin induced phosphatidylinositol (PI)- breakdown, which was examined by decreases in radioactivity and content of PI, and an increase in diacylglycerol, was not enhanced in the reserpinized platelets as compared with the control. The phosphorylation of the specific protein coupled to thrombin- induced platelet PI-breakdown was not stimulated in the reserpinized platelets as compared with the control. In contrast to PI, PC-degradation by thrombin was significantly stimulated in the reserpinized platelets. Possible existence of pathway(s) other than that associated with an enhancement of Pl-tumover is conceivable as a mechanism involved in platelet release reaction.

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