Amphiphilic Perfluoroalkylated Derivatives of Aliphatic Triols: Hemocompatibility and Effect on Perfluorocarbon Emulsion

2002 ◽  
Vol 67 (10) ◽  
pp. 1436-1448 ◽  
Author(s):  
Vladimír Církva ◽  
Robert Kaplánek ◽  
Oldřich Paleta ◽  
Milan Kodíček
Keyword(s):  
Chain Length ◽  
Hydroxy Group ◽  
Boron Trifluoride ◽  
Linear Chain ◽  
Perfluorocarbon Emulsion ◽  
Water Emulsion ◽  
Boron Trifluoride Diethyl Etherate ◽  
Primary Hydroxy Group ◽  
Derivatives Of ◽  
Very High

Two sets of amphiphilic perfluoroalkylated aliphatic triols were prepared in a two-step synthesis: a protected glycerol, 4-hydroxymethyl-2,2-dimethyl-1,3-dioxolane (1) and protected 2-hydroxymethyl-2-methylpropane-1,3-diol, 5-hydroxymethyl-2,2,5-trimethyl-1,3-dioxane (11) were fluoroalkylated with racemic 2-(2,2,3,3,4,4,5,5,5-nonafluoropentyl)- (2), or 2-(2,2,3,3,4,4,5,5,6,6,7,7,7-tridecafluoroheptyl)- (3) or 2-(2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,9-heptadecafluorononyl)oxirane (4) using boron trifluoride diethyl etherate as a catalyst to afford intermediates 5-7 and 12-14, which were deprotected by re-acetalization to the target triols HOCH2CH(OH)CH2OCH2CH(OH)CH2CF2(CF2)nCF3 (n = 2, 4, 6) 8-10 and (OHCH2)2C(CH3)CH2OCH2CH(OH)CH2CF2(CF2)nCF3 (n = 2, 4, 6) 15-17. Regioselectivity of competitive fluoroalkylation of propane-1,2-diol and butane-1,3-diol appeared to be considerably dependent on the catalyst up to 93 rel.% for the preferential fluoroalkylation at the primary hydroxy group. Hemocompatibility of the triols 8-10 and 15-17, which was very high for linear-chain amphiphiles 9 and 10, showed particular dependence on the starting triol and perfluoroalkyl-chain length. All amphiphiles 8-10 and 15-17 displayed very good compatibility with perfluorodecalin-Pluronic F-68 water emulsion.

The reactions of some 5,6-Dihalogenocyclohex-2-ene-1,4-diones (1,4-Benzoquinone dihalides) in boron trifluoride diethyl etherate

1973 ◽  
Vol 26 (2) ◽  
pp. 333 ◽  
Author(s):  
RK Norris ◽  
S Sternhell
Keyword(s):  
Boron Trifluoride ◽  
Boron Trifluoride Etherate ◽  
Hydrogen Halides ◽  
Boron Trifluoride Diethyl Etherate ◽  
High Yields ◽  
Very High

Treatment of five 1,4-benzoquinone dihalides in boron trifluoride etherate gives very high yields of isomeric dihalogenohydroquinones. With the exception of the conversion of 5,6-dichlorocyclohex-2-ene-1,4- dione into 2,3-dichlorohydroquinone, which is a true keto-enol isomerization, these products arise through elimination of hydrogen halides followed by re-addition.

Preparation of 12,20-disubstituted lupane derivatives

1979 ◽  
Vol 44 (1) ◽  
pp. 194-210 ◽  
Author(s):  
Vladimír Pouzar ◽  
Alois Vystrčil
Keyword(s):  
Hydroxy Group ◽  
Sodium Borohydride ◽  
Nmr Spectra ◽  
Unsaturated Ketone ◽  
Lithium Aluminium Hydride ◽  
H Nmr ◽  
Unsaturated Alcohols ◽  
Lithium Aluminium ◽  
Primary Hydroxy Group ◽  
Derivatives Of

Ketoester I was reduced to diol VI. The higher reactivity of its primary hydroxy group was made use of for the preparation of 12α-hydroxy derivatives VII, VIII and X the oxidation of which led to oxo derivatives XII, XIII and XIV. The reduction of the 12-oxo group in compounds XII and XIV with lithium aluminium hydride takes place stereospecifically under formation of 12α-hydroxy derivatives VII and X, while on reduction with sodium in 1-propanol corresponding 12β-hydroxy derivatives XV and XVI are also formed. Reduction of the unsaturated ketone XVII with sodium borohydride gave unsaturated alcohols XVIII and XX. As acetoxy ketone XXIV was obtained from olefin XIX in a 12% yield only, its alternative preparation was carried out from acetoxy ketone XXXIV via the intermediates XXXII, XXXV, XXVIII and XXXI in an overall yield of 27%. The structures of the derivatives of 12-lupene (III, V, XVII, XIX and XXI), 12-lupanol (II, VII, X, XV, XXXI and XXVII) and 12-lupanone (I, XII, XIII, XIV, XXIII, XXIV, XXXIII and XXXIV) were confirmed by the analysis of their 1H NMR spectra.

Coupling of Steroid O-(Carboxymethyl)oxime Derivatives with Amino Alcohols

1996 ◽  
Vol 61 (2) ◽  
pp. 288-297 ◽  
Author(s):  
Vladimír Pouzar ◽  
Ivan Černý
Keyword(s):  
Amino Acids ◽  
Hydroxy Group ◽  
Building Blocks ◽  
Amino Alcohols ◽  
New Approach ◽  
Alternative Synthesis ◽  
Oxime Derivatives ◽  
A Chain ◽  
Derivatives Of

New approach to the preparation of steroids with connecting bridge, based on an O-carboxymethyloxime (CMO) structure, and with terminal hydroxy group, is presented. 17-CMO derivatives of 3β-acetoxy- and 3β-methoxymethoxyandrost-5-en-17-one were condensed with α,ω-amino alcohols to give derivatives with a chain of seven to nine atoms. After THP-protection, these compounds were converted to 3-keto-4-ene derivatives. An alternative synthesis consisted in transformation of 17-CMO derivatives with bonded amino acids by reduction of the terminal carboxyl. The resulting compounds were designed as building blocks for the preparation of bis-haptens for sandwich immunoassays.

Direct Etherification of a Single Primary Hydroxy Group of β-Cyclodextrin

2021 ◽  
Vol 57 (1) ◽  
pp. 121-125
Author(s):  
N. V. Kutyasheva ◽  
G. I. Kurochkina ◽  
E. A. Solomatin ◽  
M. K. Grachev
Keyword(s):  
Hydroxy Group ◽  
Primary Hydroxy Group

scholarly journals Spin-labeling of Dexamethasone: Radical Stability vs. Temporal Resolution of EPR-Spectroscopy on Biological Samples

2018 ◽  
Vol 232 (5-6) ◽  
pp. 883-891 ◽  
Author(s):  
Karolina A. Walker ◽  
Michael L. Unbehauen ◽  
Silke B. Lohan ◽  
Siavash Saeidpour ◽  
Martina C. Meinke ◽  
...  
Keyword(s):  
Detection Limit ◽  
Hydroxy Group ◽  
Epr Spectroscopy ◽  
Biological Samples ◽  
Spin Labeling ◽  
Hacat Cells ◽  
Nmr Data ◽  
Primary Hydroxy Group ◽  
High Yields ◽  
Stability Measurements

AbstractSpin-labeling active compounds is a convenient way to prepare them for EPR spectroscopy with minimal alteration of the target molecule. In this study we present the labeling reaction of dexamethasone (Dx) with either TEMPO (2,2,6,6-tetramethyl-1-piperidinyloxy) or PCA (3-(carboxy)-2,2,5,5-tetramethyl-1-pyrrolidinyloxy) with high yields. According to NMR data, both labels are attached at the primary hydroxy group of the steroid. In subsequent spin-stability measurements both compounds were applied onto HaCaT cells. When the signal of Dx-TEMPO decreased below the detection limit within 3 h, the signal of Dx-PCA remained stable for the same period of time.

Aminocyclitols. II. Synthesis of thioanalogues of 2,5-dideoxystreptamine

1978 ◽  
Vol 56 (21) ◽  
pp. 2743-2749 ◽  
Author(s):  
Gerry Kavadias ◽  
Robert Droghini
Keyword(s):  
Thionyl Chloride ◽  
Boron Trifluoride ◽  
Protective Groups ◽  
Thiobenzoic Acid ◽  
Derivatives Of ◽  
L 13

N,N′-Dibenzoyl-2,5-dideoxystreptamine (8b) reacted with thionyl chloride to form the bisoxazoline 9 and the latter compound was treated with thiobenzoic acid to produce the dithiobenzoate 10a. Removal of the protective groups in 10a afforded (l,3/4,6)-4,6-diamino-1,3-cyclohexanedithiol (1) dihydrochloride. Reaction of 8b with triethyl orthoacetate in the presence of boron trifluoride yielded the monooxazoline 12 which, on reaction with thiobenzoic acid followed by deprotection of the resulting 13a, afforded (d,l)-(13/4,6)-4,6-diamino-3-hydroxycyclohexanethiol (2) dihydrochloride. Similarly, 3-N-benzoyl-1-N-ethoxycarbonyl-2,5-dideoxystreptamine (15) and l-N-benzoyl-3-N-ethoxycarbonyl-2,5-dideoxystreptamine (20) were converted via their respective oxazolines 17a and 22a, to the enantiomeric aminothiols 3 and 4. Protected derivatives of 1–4 are also described.

Electrosyntheses of Poly(selenophene-co-3-methylthiophene) with Improved Thermoelectric Property in Boron Trifluoride Diethyl Etherate

2014 ◽  
Vol 937 ◽  
pp. 17-22 ◽  
Author(s):  
Sheng Tao Wang ◽  
Bao Yang Lu ◽  
Jing Kun Xu ◽  
Wei Qiang Zhou
Keyword(s):  
Cyclic Voltammetry ◽  
Infrared Spectroscopy ◽  
Electrochemical Oxidation ◽  
Thermoelectric Property ◽  
Boron Trifluoride ◽  
Monomer Concentration ◽  
Thermoelectric Measurements ◽  
Boron Trifluoride Diethyl Etherate ◽  
Concentration Ratios

Novel poly (selenophene-co-3-methylthiophene) was successfully achieved by directly electrochemical oxidation of the monomer mixtures of selenophene and 3-methylthiophene (3MeT) in boron trifluoride diethyl etherate. The effect of monomer concentration ratios on the copolymerization were investigated by cyclic voltammetry. The structures of as-prepared copolymers were characterized by UV-vis and infrared spectroscopy. The conductivity and thermoelectric measurements revealed the incorporation of 3MeT into the polyselenophene (PSe) chain improved significantly the conductivity and thermoelectric property of PSe.

scholarly journals The multiple complexes formed by the interaction of platelet factor 4 with heparin

1980 ◽  
Vol 191 (3) ◽  
pp. 769-776 ◽  
Author(s):  
P E Bock ◽  
M Luscombe ◽  
S E Marshall ◽  
D S Pepper ◽  
J J Holbrook
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Chain Length ◽  
Salt Concentration ◽  
Human Platelet ◽  
Platelet Factor 4 ◽  
High Protein ◽  
Platelet Factor ◽  
The Stability ◽  
Very High

The anisotropy of the fluorescence of dansyl (5-dimethylaminonaphthalene-1- sulphonyl) groups covalently attached to human platelet factor 4 was used to detect the macromolecular compounds formed when the factor was mixed with heparin. At low heparin/protein ratios a very-high-molecular-weight compound (1) was formed that dissociated to give a smaller compound (2) when excess heparin was added. 2. A large complex was also detected as a precipitate that formed at high protein concentrations in chloride buffer. It contained 15.7% (w/w) polysaccharide, equivalent to four or five heparin tetrasaccharide units per protein tetramer. In this complex, more than one molecule of protein binds to each heparin molecule of molecular weight greater than about 6 × 10(3).3. The stability of these complexes varied with pH, salt concentration and the chain length of the heparin. The limit complexes found in excess of the larger heparins consisted of only one heparin molecule per protein tetramer, and the failure to observe complexes with four heparin molecules/protein tetramer is discussed.

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