Isolation and characterization of polydentate ligands derived from the reaction of pentaerythrityltetrabromide and ethylenediamine

1989 ◽  
Vol 67 (10) ◽  
pp. 1657-1665 ◽  
Author(s):  
A. McAuley ◽  
K. Beveridge ◽  
S. Subramanian ◽  
T. W. Whitcombe
Keyword(s):  
Diethyl Malonate ◽  
Ring Closure ◽  
Polydentate Ligands ◽  
Isolation And Characterization ◽  
Free Amine ◽  
Square Planar ◽  
Bonding Interaction ◽  
Hydrolysis Of ◽  
Amine Hydrochlorides

Reaction of pentaerythrityltetrabromide with ethylenediamine yields three product amines. These have been isolated by separation of the corresponding Ni2+ complexes. The free amine hydrochlorides have been obtained by acid hydrolysis of the Ni2+ species and have been characterized by nuclear magnetic resonance and mass spectroscopy. The crystal structures have been determined for the hexahydrochloride salt of polyamine ligand L1, [H6(L1)]Cl6•4H2O (L1 = C11H28N6, 6,6-bis(4-amino-2-azabutyl)-1,4-diazacycloheptane)(C2/c, a = 15.975) Å, b = 10.723 (1) Å, c = 14.686(1) Å, β = 99.40(1)°, Z = 4), and for the octahydrochloride salt of L2, [H2(L2)Cl8•2H2O (L2 = 5,5-bis(4-amino-2-azabutyl)-1,9-diamino-3,7-diazanonane) (Pccn, a = 12.834(2) Å, b = 16.691(1) Å, c = 14.167(1) Å, Z = 4). Both crystals exhibit strong N—H … Cl,O,N bonding, although in the latter compound the waters of crystallization do not participate in the apparent hydrogen bonding interaction. Both these species are of interest since they represent the precursors to square planar Ni2+ complexes that incorporate the MN4 chromophore. Ring closure of both the free amines L1 and L2 by reaction with diethyl malonate leads to cyclized products that are related to the cyclam ([14-aneN4) tetraaza macrocylic ligands. Keywords: pentaerythrityl, amine, spiro ligand hydrochlorides.

Isolation and characterization of anti-inflammatory peptides derived from trypsin hydrolysis of microalgae protein (Synechococcus sp. VDW)

2019 ◽  
Vol 33 (4) ◽  
pp. 303-324 ◽  
Author(s):  
Rutairat Suttisuwan ◽  
Saranya Phunpruch ◽  
Tanatorn Saisavoey ◽  
Papassara Sangtanoo ◽  
Nuttha Thongchul ◽  
...  
Keyword(s):  
Isolation And Characterization ◽  
Trypsin Hydrolysis ◽  
Synechococcus Sp ◽  
Anti Inflammatory ◽  
Hydrolysis Of

scholarly journals Isolation and characterization of a γ-type phosphoinositide-specific phospholipase C (PLC-γ2)

1990 ◽  
Vol 269 (1) ◽  
pp. 13-18 ◽  
Author(s):  
Y Homma ◽  
Y Emori ◽  
F Shibasaki ◽  
K Suzuki ◽  
T Takenawa
Keyword(s):  
Phospholipase C ◽  
Column Chromatography ◽  
Specific Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Deae Cellulose ◽  
Isolation And Characterization ◽  
Delta Type ◽  
Hydrolysis Of ◽  
Cellulose Column

A novel bovine spleen phosphoinositide-specific phospholipase C (PLC) has been identified with respect to immunoreactivity with four independent antibodies against each of the PLC isoenzymes, and purified to near homogeneity by sequential column chromatography. Spleen contains three of the isoenzymes: two different gamma-types [gamma 1 and gamma 2, originally named as PLC-gamma [Rhee, Suh, Ryu & Lee (1989) Science 244, 546-550] and PLC-IV [Emori, Homma, Sorimachi, Kawasaki, Nakanishi, Suzuki & Takenawa (1989) J. Biol. Chem. 264, 21885-21890] respectively] and delta-type of the enzyme, but PLC-gamma 1 is separated from the PLC-gamma 2 pool by the first DEAE-cellulose column chromatography. Subsequently, PLC-delta is dissociated on the third heparin-Sepharose column chromatography. The purified enzyme has a molecular mass of 145 kDa on SDS/polyacrylamide-gel electrophoresis and a specific activity of 12.8 mumol/min per mg with phosphatidylinositol 4,5-bisphosphate as substrate. This enzyme activity is dependent on Ca2+ for hydrolysis of all these phosphoinositides. None of the other phospholipids examined could be its substrate at any concentration of Ca2+. The optimal pH of the enzyme is slightly acidic (pH 5.0-6.5).

The Isolation and Characterization of Square Planar, Square Pyramidal, and Octahedral Copper(II) Complexes with Mixed Ligands

1978 ◽  
Vol 33 (8) ◽  
pp. 906-910 ◽  
Author(s):  
M. M. Aly
Keyword(s):  
Vibrational Spectra ◽  
Dichloroacetic Acid ◽  
Chemical Analyses ◽  
Cleavage Reaction ◽  
Mixed Ligands ◽  
Isolation And Characterization ◽  
Square Planar ◽  
Electronic And Vibrational Spectra ◽  
Heterocyclic Bases

Substitution of an acetylacetonate by a carboxylate in the neutral (acac)2Cu(II) was achieved by its reaction with tri- and dichloroacetic acid in benzene (HCO2R where R = CCl3 or CHCl2; Hacac = acetylacctone) which led to the formation of the mixed chelate square planar complex (acac)Cu(OCOR). The later complex, R = CCl3, reacted with heterocyclic bases to produce the square pyramidal complexes (acac)Cu(OCOR) (base), (base = 2- methylpyridine or quinoline); with ethylenediamine (en) to give the octahedral [(en)2Cu(OCOR)]Cl, and with methanol and piperidine or boiling methanol alone to give the methoxo-bridged (acac)Cu(OCH3)2Cu(acac). The reaction of acetylacetonate-carboxy- late-copper(II) complex (R = CHCl2) with heterocyclic bases led to the cleavage of the acetylacetonate ligand and the formation of the octahedral Cu(OCOCHCl2) · 2 base (base = pyridine, 2-, 3- or 4-methylpyridine). The same cleavage reaction took place, and also with R = CCl3, in their reaction with 8-hydroxyquinoline to form the mixed chelates (ROCO)Cu(Oxinate). These formulations are based on chemical analyses, electronic and vibrational spectra, and on conductance measurements.

scholarly journals Ectoenzymes of the kidney microvillar membrane. Isolation and characterization of the amphipathic form of renal dipeptidase and hydrolysis of its glycosyl-phosphatidylinositol anchor by an activity in plasma

1989 ◽  
Vol 261 (3) ◽  
pp. 811-818 ◽  
Author(s):  
N M Hooper ◽  
A J Turner
Keyword(s):  
Membrane Anchor ◽  
Glycosyl Phosphatidylinositol ◽  
Isolation And Characterization ◽  
C Terminus ◽  
Terminal Amino ◽  
Membrane Isolation ◽  
Solubilized Form ◽  
Triton X ◽  
Hydrolysis Of

Renal dipeptidase (EC 3.4.13.11) has been solubilized from pig kidney microvillar membranes with n-octyl-beta-D-glucopyranoside and then purified by affinity chromatography on cilastatin-Sepharose. The enzyme exists as a disulphide-linked dimer of two identical subunits of Mr 45,000 each. The purified dipeptidase partitioned into the detergent-rich phase upon phase separation in Triton X-114 and reconstituted into liposomes consistent with the presence of the glycosyl-phosphatidylinositol membrane anchor. The N-terminal amino acid sequence of the amphipathic, detergent-solubilized, form of renal dipeptidase was identical with that of the hydrophilic, phospholipase-solubilized, form, locating the membrane anchor at the C-terminus of the protein. The glycosyl-phosphatidylinositol anchor of both purified and microvillar membrane renal dipeptidase was a substrate for an activity in pig plasma which displayed properties similar to those of a previously described phospholipase D. The cross-reacting determinant of the glycosyl-phosphatidylinositol anchor was generated by incubation of purified renal dipeptidase with bacterial phosphatidylinositol-specific phospholipase c, whereas the anchor-degrading activity in plasma failed to generate this determinant.

Hydrolyse von Per(fluorchlor)methylsulfenylchloriden: Isolierung und Charakterisierung stabiler Zwischenstufen / Hydrolysis of Per(fluorochloro)methylsulfenylchlorides: Isolation and Characterization of Stable Intermediates

1985 ◽  
Vol 40 (1) ◽  
pp. 32-38
Author(s):  
Alois Haas ◽  
Wolfgang Wanzke ◽  
Nathan Welcman
Keyword(s):  
Preparative Scale ◽  
Isolation And Characterization ◽  
Hydrolysis Of

Hydrolysis of CF3-nClnSCl with water yields the thiosulfinates CF3-nClnSS(O)CF3-nCln and thiosulfonates CF3-nClnSSO2CF3-nCln as stable intermediates. They were synthesized on a preparative scale by special reactions and characterized. A new mechanism, based upon additional reactions of the isolated products, is discussed and extended to the reaction of chlorine with water

CARBOXYLATION OF CROTONYL-CoA BY MAMMALIAN ENZYME SYSTEMS

1966 ◽  
Vol 44 (6) ◽  
pp. 861-878 ◽  
Author(s):  
E. Reno Tustanoff ◽  
Joseph R. Stern
Keyword(s):  
Carbon Dioxide ◽  
Enzyme System ◽  
Test System ◽  
Diabetic Rats ◽  
Isolation And Characterization ◽  
Unsaturated Acyl ◽  
Liver Preparation ◽  
Mammalian Enzyme ◽  
Hydrolysis Of

In a crude dialyzed ammonium sulfate fraction (35–65% saturation) of rat liver, carbon dioxide fixation into crotonyl-CoA took place when the test system was supplemented with ATP, Mn++, glutathione, Tris–HCl buffer (pH 7.0), and KH14CO3. The products of this reaction were identified after hydrolysis as glutaconic, β-hydroxyglutaric, maionic, and 2-ethylmalonic acids. The isolation and characterization of 5-14C-glutaconyl-CoA indicated a γ-carboxylation reaction. In the presence of endogenous enoyl-CoA hydratase, crotonyl-CoA was carboxylated more readily than β-hydroxybutyryl-CoA, suggesting that the unsaturated acyl compound was the natural substrate for the enzyme system. Carboxylation of crotonyl-CoA was greatly enhanced when liver extracts were prepared from either fasted or alloxan-diabetic rats. Fixation of carbon dioxide into crotonyl-CoA was also demonstrated with an amorphous preparation of propionyl-CoA carboxylase from pig heart. The products of this reaction were identified as radioactive malonic acid and unlabeled acetaldehyde, compounds which resulted from the alkaline hydrolysis of 2-ethylidenemalonyl-CoA, formed by the α-carboxylation of crotonyl-CoA. Evidence is presented that both α- and γ-carboxylation are catalyzed by the crude liver preparation.

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