scholarly journals FLUORESCENCE METHODS FOR THE HISTOCHEMICAL DEMONSTRATION OF MONOAMINES: 4. HISTOCHEMICAL DIFFERENTIATION BETWEEN DOPAMINE AND NORADRENALINE IN MODELS

1965 ◽  
Vol 13 (6) ◽  
pp. 484-487 ◽  
Author(s):  
HANS CORRODI ◽  
GÖSTA JONSSON
Keyword(s):  
Hydroxy Group ◽  
Sodium Borohydride ◽  
Thionyl Chloride ◽  
Emission Spectra ◽  
Histochemical Demonstration ◽  
Protein Layer ◽  
Fluorescence Methods ◽  
Fluorescent Products ◽  
Gaseous Formaldehyde

If primary catecholamines e.g. dopamine and noradrenaline in a dried protein layer are exposed to gaseous formaldehyde, they are converted to intensely fluorescent 6,7-dihydroxy-3,4-dihydroisoquinolines. This reaction can be used for the histochemical demonstration of these amines. The fluorescent products of dopamine and noradrenaline have practically identidal activation and emission spectra. The 4,6,7-trihydroxy-3,4-dihydroisoquinoline formed from noradrenaline has, however, a labile hydroxy group at 4-position which can be easily split off. This dehydration to the fully aromatic 6,7-dihydroxyisoquinoline was found to take place readily in a dried protein layer by treatment with thionyl chloride gas at 50°C. The isoquinoline shows other flurorescence characteristics than the 3,4-dihydroisoquinolines and is not reduced by sodium borohydride. A direct histochemical differentiation between dopamine and noradrenaline is thus possible.

scholarly journals ACID CATALYSIS OF THE FORMALDEHYDE CONDENSATION REACTION FOR SENSITIVE HISTOCHEMICAL DEMONSTRATION OF TRYPTAMINES AND 3-METHOXYLATED PHENYLETHYLAMINES

1970 ◽  
Vol 18 (11) ◽  
pp. 794-802 ◽  
Author(s):  
ANDERS BJÖRKLUND ◽  
ULF STENEVI
Keyword(s):  
Acid Catalysis ◽  
Condensation Reaction ◽  
Fluorescence Yield ◽  
Histochemical Demonstration ◽  
Formaldehyde Treatment ◽  
Hcl Gas ◽  
Fluorescent Products ◽  
Acid Catalyzed ◽  
Gaseous Formaldehyde ◽  
Related Compounds

Hydrochloric acid catalyzes the formation of fluorophores in the histochemical condensation reaction between gaseous formaldehyde and certain phenylethylamines and indolylethylamines. Thus, when the formaldehyde reaction is carried out in the presence of minute amounts of HCl gas, 3-methoxy-4-hydroxyphenylethylamine, 3,4-dimethoxyphenylalanine and tryptamine displayed a fluorescence yield approximately 20-200 times higher than that obtained after standard formaldehyde treatment in normal air ( i.e., the conditions of the Falck-Hillarp method). This fluorescence intensity was nearly twice as high as that obtained from noradrenaline and dopamine under the standard conditions. The results indicate that the acid catalyzes the first step of the histochemical reaction, i.e., the Pictet-Spengler condensation reaction. In this step low fluorescent tetrahydroisoquinolines and tetrahydro-β-carbolines are formed, which are subsequently dehydrogenated to strongly fluorescent products. Low reactive aromatic amines and amino acids, such as phenylalanine, tyrosine, amphetamine and melatonin, gave no or only very low visible fluorescence after this treatment. Thus, the acid-catalyzed histochemical formaldehyde reaction described in this paper exhibits a good specificity for indolylethylamines and 3-hydroxylated or 3-methoxylated phenylethylamines and will also allow the distinction between these structurally related compounds on the basis of their reactivity in the condensation reaction.

Synthesis and Antibacterial Activity of Some 3-Hydroxyquinolones

1992 ◽  
Vol 57 (1) ◽  
pp. 188-193 ◽  
Author(s):  
Stanislav Rádl ◽  
Magda Janichová
Keyword(s):  
Antibacterial Activity ◽  
Carboxylic Acid ◽  
Hydroxy Group ◽  
Sodium Borohydride ◽  
Selenium Dioxide ◽  
Prolonged Heating

A reductive decarboxylation of 7-chloro-1-ethyl-6-fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid (Id) with sodium borohydride provided the respective 1,2,3,4-tetrahydro derivative Va, which was treated with selenium dioxide to give product of dehydrogenation VIa. 3-Acetyl-1-ethyl-1,4-dihydroquinolin-4-ones VIb and VIc were oxidized with 3-chloroperoxybenzoic acid to the respective 3-hydroxyderivatives IIIa and IIIb. Compound IIIb was benzylated on a hydroxy group at position 3 to corresponding 3-benzyloxy derivative VIf which after prolonged heating with N-methylpiperazine in a sealed tube provided directly 3-hydroxy-7-(4-methyl-1-piperazinyl) derivative IIIc.

An Efficient, Large-Scale Synthesis of Cytenamide

2018 ◽  
Vol 42 (3) ◽  
pp. 153-155
Author(s):  
Colin T. Bedford
Keyword(s):  
Sodium Borohydride ◽  
Thionyl Chloride ◽  
Large Scale ◽  
Large Scale Synthesis ◽  
Nitrile Hydrolysis

Dibenzosuberenone (5 H-dibenzo[a,d]cyclohepten-5-one) was reduced to the corresponding alcohol by sodium borohydride/MeOH and converted to the corresponding 5-chloro compound by thionyl chloride/benzene, treatment of which with CuCN/toluene gave the corresponding nitrile. Hydrolysis by ethanolic KOH yielded the corresponding amide, cytenamide (5 H-dibenzo[a,d]cycloheptene-5-carboxamide).

scholarly journals Demonstration of catecholamine and resorcinolamine derivatives as formaldehyde-induced fluorescence in protein models.

1988 ◽  
Vol 36 (6) ◽  
pp. 615-620
Author(s):  
L J Bryan ◽  
S R O'Donnell
Keyword(s):  
Fluorescence Intensity ◽  
Alkyl Chain ◽  
Emission Spectra ◽  
Ring Structure ◽  
Histochemical Demonstration ◽  
Wide Range ◽  
Protein Models ◽  
Fluorescence Microphotometry ◽  
Potential Use ◽  
Long Alkyl Chain

We assessed in protein droplet models the potential use of the formaldehyde condensation method for histochemical demonstration of a wide range of catecholamines and resorcinolamines. The experiments showed that all of the amines tested, except salbutamol and carbuterol, formed fluorophores, and that the fluorescence was specific [i.e., there was no fluorescence in the absence of formaldehyde, the fluorescence was quenched by water, and the fluorophores were subject to photodecomposition by the exciting (405-nm) light]. Peak wavelengths of the emission spectra were 480-485 nm for fluorophores of resorcinolamine derivatives. The fluorescence intensity of the catecholamines was greater than that of the resorcinolamines. Fluorophore formation was not hindered by substitution of t-butyl, phenylisoprophyl, or p-hydroxyphenylisopropyl on the amino-N in catecholamines (t-butylnorepinephrine, Cc24, Cc25, respectively) or resorcinolamines (terbutaline, Th1161, fenoterol, respectively), and fluorophores also formed for catecholamines with the amino-N in a ring structure (rimiterol) or with a long alkyl chain substituted on the amino-N (hexoprenaline). Our study showed that fluorescence microphotometry can be used to detect a range of drugs that are catecholamines or resorcinolamines, and hence it should be possible to use this technique to study the properties of dissipation of these amines in tissues.

Synthesis and Biological Activity of New 16,17-Secoestrone Derivatives

2000 ◽  
Vol 65 (1) ◽  
pp. 77-82 ◽  
Author(s):  
Suzana Jovanović-Šanta ◽  
Silvana Andrić ◽  
Radmila Kovačević ◽  
Vjera Pejanović
Keyword(s):  
Biological Activity ◽  
Hydroxy Group ◽  
Sodium Borohydride ◽  
Estrogenic Activity ◽  
Complete Loss ◽  
Borohydride Reduction ◽  
Experimental Animals ◽  
Biological Tests ◽  
Sodium Borohydride Reduction

Starting from estrone 3-benzyloxy-17β-hydroxyestra-1,3,5(10)-trien-16-one oxime (3b) was synthesized, which underwent Beckmann fragmentation giving the 3-benzyloxy-17-oxo- 16,17-secoestra-1,3,5(10)-triene-16-nitrile (4b). Sodium borohydride reduction of this compound afforded 3-benzyloxy-17-hydroxy-16,17-secoestra-1,3,5(10)-triene-16-nitrile (5b). The deprotection of the 3-hydroxy group was achieved by action of hydrogen upon derivatives 4b and 5b in presence of Pd/C as a catalyst, yielding 3-hydroxy-17-oxo-16,17-secoestra- 1,3,5(10)-triene-16-nitrile (4a) and 3,17-dihydroxy-16,17-secoestra-1,3,5(10)-triene-16-nitrile (5a). In biological tests on experimental animals, compounds 4a, 4b, 5a and 5b showed virtually a complete loss of estrogenic activity, whereas compounds 4a, 5a and 5b exhibited moderate antiestrogenic effect.

scholarly journals Tyrosine and tyrosinate fluorescence of pig intestinal Ca2+-binding protein

1987 ◽  
Vol 243 (2) ◽  
pp. 611-615 ◽  
Author(s):  
J D J O'Neil ◽  
T Hofmann
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Emission Spectrum ◽  
Hydroxy Group ◽  
Binding Proteins ◽  
Binding Protein ◽  
Emission Spectra ◽  
Difference Spectrum ◽  
Tyrosine Residue

The single tyrosine residue in both pig and cow intestinal Ca2+-binding proteins fluoresces at 303 nm although the crystal structure of the cow protein shows a hydrogen bond between the hydroxy group of the tyrosine and glutamate-38 [Szebenyi & Moffat (1986) J. Biol. Chem. 261, 8761-8777]. The latter interaction suggests that tyrosinate fluorescence should dominate the emission spectra of these proteins. A fluorescence difference spectrum, produced by subtracting the spectrum of free tyrosine from the spectrum of the protein, gives a peak at 334 nm due to ionized tyrosine. That this component of the emission spectrum is not due to a tryptophan-containing contaminant is shown by its elimination when the protein is denatured by guanidine and when glutamate-38 is protonated. We conclude that, in solution, the tyrosine residue in this protein interacts occasionally with glutamate-38 but that a permanent hydrogen bond is not formed.

Fluorescence histochemical demonstration of dopa thioethers by condensation with gaseous formaldehyde

1977 ◽  
Vol 52 (2) ◽  
pp. 179-186 ◽  
Author(s):  
Gun Agrup ◽  
Anders Bj�rklund ◽  
Bengt Falck ◽  
Sten Jacobsson ◽  
Olle Lindvall ◽  
...  
Keyword(s):  
Histochemical Demonstration ◽  
Gaseous Formaldehyde
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