SYNTHESIS OF DIPALMITOYL-L-α-GLYCEROPHOSPHORIC ACID DERIVATIVES, AS POSSIBLE INTERMEDIATES FOR SYNTHESIS OF GLYCERYLPHOSPHATIDES

1960 ◽  
Vol 38 (1) ◽  
pp. 297-300 ◽  
Author(s):  
N. Z. Stanacev ◽  
M. Kates
Keyword(s):  
Melting Point ◽  
Phosphatidic Acid ◽  
Good Yield ◽  
Dimethyl Ester ◽  
Specific Rotation ◽  
Optically Active ◽  
Phosphatidic Acids ◽  
Alternate Synthesis

Using Verkade's method for the preparation of DL-α-phosphatidic acids, optically active dipalmitoyl-L-α-phosphatidic acid and its derivatives were prepared in good yield. The free dipalmitoyl-L-α-phosphatidic acid and its dimethyl ester were identical in melting point and specific rotation with the same compounds originally prepared by Baer using an alternate synthesis.

SYNTHESIS OF DIPALMITOYL-L-α-GLYCEROPHOSPHORIC ACID DERIVATIVES, AS POSSIBLE INTERMEDIATES FOR SYNTHESIS OF GLYCERYLPHOSPHATIDES

1960 ◽  
Vol 38 (3) ◽  
pp. 297-300 ◽  
Author(s):  
N. Z. Stanacev ◽  
M. Kates
Keyword(s):  
Melting Point ◽  
Phosphatidic Acid ◽  
Good Yield ◽  
Dimethyl Ester ◽  
Specific Rotation ◽  
Optically Active ◽  
Phosphatidic Acids ◽  
Alternate Synthesis

Using Verkade's method for the preparation of DL-α-phosphatidic acids, optically active dipalmitoyl-L-α-phosphatidic acid and its derivatives were prepared in good yield. The free dipalmitoyl-L-α-phosphatidic acid and its dimethyl ester were identical in melting point and specific rotation with the same compounds originally prepared by Baer using an alternate synthesis.

scholarly journals Microwave-assisted synthesis and characterization of some optically active poly(ester-imide) thermoplastic elastomers

e-Polymers ◽  
2009 ◽  
Vol 9 (1) ◽  
Author(s):  
Saeed Zahmatkesh ◽  
Abdol Reza Hajipour
Keyword(s):  
Thermal Analyses ◽  
Specific Rotation ◽  
Thermoplastic Elastomers ◽  
Optically Active ◽  
Microwave Assisted Synthesis ◽  
H Nmr ◽  
Microwave Assisted ◽  
Diacid Chloride ◽  
Elemental Analyses

AbstractPyromellitic dianhydride (1) was reacted with L-leucine (2) to result in [N,N'-(pyromellitoyl)-bis-L-leucine diacid] (3). This compound (3) was converted to N,N'-(pyromellitoyl)-bis-L-leucine diacid chloride (4) by reaction with thionyl chloride. The microwave-assisted polycondensation of this diacid chloride (4) with polyethyleneglycol-diol (PEG-200) and/or three synthetic bisphenols furnish a series of new PEIs and Co-PEIs in a laboratory microwave oven (Milestone). The resulting polymers and copolymers have inherent viscosities in the range of 0.31- 0.53 dl g-1. These polymers are optically active, thermally stable and soluble in polar aprotic solvents such as DMF, DMSO, NMP, DMAc and sulfuric acid. All of the above polymers were fully characterized by IR spectroscopy, 1H NMR spectroscopy, elemental analyses, specific rotation and thermal analyses. Some structural characterizations and physical properties of these optically active PEIs and Co-PEIs are reported.

LINOLEIC ACID AND ITS ISOMERS

1938 ◽  
Vol 16b (5) ◽  
pp. 158-175 ◽  
Author(s):  
J. W. McCutcheon
Keyword(s):  
Linoleic Acid ◽  
Melting Point ◽  
Sunflower Seed ◽  
Seed Oil ◽  
Additional Data ◽  
Free Acid ◽  
Optically Active ◽  
Naturally Occurring ◽  
Tetrabromostearic Acid ◽  
Asymmetric Carbon

Linoleic acid has been prepared from sunflower seed oil by a modification of Rollett's method. The melting point of the solid tetrabromostearic acid is placed at 115.2 °C. The boiling point, specific gravity, iodine value, and refractive index of the ethyl ester and the melting point of the free acid were determined. Linoleamide was prepared, and its melting point is placed at approximately 58 °C. Through rebromination of the prepared linoleic acid, the isomeric liquid tetrabromostearic acid was isolated, and is described. Its reduced acid is shown to be identical with that derived from the solid isomer. From these data and additional data from the literature, it was concluded that bromination and debromination cause no cis-trans isomerization, and that the two pairs of optically active enantiomorphous bromo derivatives exist, not because of their derivation from different acids, but rather because of the four asymmetric carbon atoms which they contain. Therefore, only one naturally occurring linoleic acid is at present known which is identical with that produced through reduction of the tetrabromide that melts at 115.2 °C. or the corresponding liquid derivative. No attempt is made to assign any particular cis-trans configuration to this acid, or to exclude the theoretical existence of three others.

scholarly journals Chiral carboxylic acids and their effects on melting-point behaviour in co-crystals with isonicotinamide

2008 ◽  
Vol 64 (6) ◽  
pp. 780-790 ◽  
Author(s):  
Andreas Lemmerer ◽  
Nikoletta B. Báthori ◽  
Susan A. Bourne
Keyword(s):  
Melting Point ◽  
Crystal Structures ◽  
Carboxylic Acids ◽  
Optically Active ◽  
Phenylpropionic Acid ◽  
Space Groups ◽  
Two Systems ◽  
Packing Arrangement ◽  
Phenylbutyric Acid

The crystal structures of co-crystals of two systems of chiral carboxylic acids, optically active and racemic 2-phenylpropionic acid and 2-phenylbutyric acid, with isonicotinamide are reported to investigate the effects of the chirality of the chiral carboxylic acids on the melting point of the co-crystal complexes. It was found that the racemic co-crystal has a higher melting point than the optically active co-crystal, which correlates with the denser packing arrangement inherent in centrosymmetric space groups.

PHYSICAL CONSTANTS AND ESTIMATION OF STEREOISOMERIC 2,3-BUTANEDIOLS

1951 ◽  
Vol 29 (10) ◽  
pp. 885-894 ◽  
Author(s):  
R. W. Watson ◽  
J. A. R. Coope ◽  
J. L. Barnwell
Keyword(s):  
Refractive Index ◽  
Pilot Plant ◽  
Experimental Error ◽  
Specific Rotation ◽  
Optically Active ◽  
Temperature Relation ◽  
Aerobacter Aerogenes ◽  
Physical Constants ◽  
Beet Molasses

The refractive index – temperature relation for optically active and racemic diols is linear, with [Formula: see text] from 25° to 40°C.: for the meso-isomer [Formula: see text] from 25° to 50°C. The specific rotation [Formula: see text]. Measurements of [Formula: see text] and [Formula: see text] in suitably purified mixtures of stereoisomers allow calculation of the percentage of each isomer present. Tests of the method on known mixtures of all three stereoisomers show an experimental error of ±3%. Analyses of five diol samples from pilot plant fermentations of beet molasses by Aerobacter aerogenes reveal 65–87% meso-, from 2 to 16% dextro-, and from 0 to 33% racemic 2,3-butanediol.

scholarly journals AP212121polymorph of (+)-clusianone

2013 ◽  
Vol 69 (12) ◽  
pp. o1799-o1800
Author(s):  
Sree Vaneesa Nagalingam ◽  
Janet Wong Pik Ching ◽  
Mohammed Khaled bin Break ◽  
M. Ibrahim M. Tahir ◽  
Teng-Jin Khoo
Keyword(s):  
Hydrogen Bond ◽  
Melting Point ◽  
Structure Determination ◽  
Title Compound ◽  
Specific Rotation ◽  
Slow Evaporation ◽  
Orthorhombic Space Group ◽  
Acta Cryst ◽  
Space Group ◽  
Compound C

The title compound, C33H42O4[systematic name: (1S,5S,7R)-3-benzoyl-4-hydroxy-8,8-dimethyl-1,5,7-tris(3-methylbut-2-enyl)bicyclo[3.3.1]nona-3-ene-2,9-dione], has a central bicyclo[3.3.1]nonane-2,4,9-trione surrounded by tetraprenylated and benzoyl groups. The compound was recrystallized several times in methanol using both a slow evaporation method and with a crystal-seeding technique. This subsequently produced diffraction-quality crystals which crystallize in the orthorhombic space groupP212121, in contrast to a previous report of a structure determination in thePna21space group [McCandlishet al.(1976).Acta Cryst. B32, 1793–1801]. The title compound has a melting point of 365–366 K, and a specific rotation [α]20value of +51.94°. A strong intramolecular O—H...O hydrogen bond is noted. In the crystal, molecules are assembled in theabplane by weak C—H...O interactions.

ON THE SYNTHESIS OF OPTICALLY ACTIVE β-PHOSPHATIDIC ACIDS

1943 ◽  
Vol 21b (6) ◽  
pp. 119-124 ◽  
Author(s):  
Erich Baer ◽  
Ira B. Cushing ◽  
Hermann O. L. Fischer
Keyword(s):  
Optically Active ◽  
Phosphatidic Acids ◽  
New Compounds

A method is outlined for the synthesis of one series of optically active β-phosphatidic acids from d(+)acetone glycerol. The syntheses of the following new compounds are described: l(−)α-benzoyl glycerol, α′-trityl l-α-benzoyl glycerol, potassium α′-trityl-α-benzoyl β-glycerophosphate (active and racemic), and potassium α-benzoyl β-glycerophosphate (racemic).

scholarly journals Synthesis and Characterization of New Optically Active Poly (ethyl L-lysinamide)s and Poly (ethyl L-lysinimide)s

2010 ◽  
Vol 2010 ◽  
pp. 1-6 ◽  
Author(s):  
Saeed Zahmatkesh ◽  
Mohammad Reza Vakili
Keyword(s):  
Nmr Spectroscopy ◽  
Elemental Analysis ◽  
Specific Rotation ◽  
Viscosity Measurement ◽  
Optically Active ◽  
Inherent Viscosity ◽  
Synthesis And Characterization

Ethyl L-lysine dihydrochloride was reacted with three different dianhydrides to yield the poly (ethyl L-lysinimide)s ( NMR spectroscopy, elemental analysis, WAX diffraction, TGA, inherent viscosity measurement, and specific rotation.

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