Chemistry of the aminochromes. Part XI. Studies on 2-methylaminochromes

1969 ◽  
Vol 47 (11) ◽  
pp. 2003-2007 ◽  
Author(s):  
O. Hutzinger ◽  
R. A. Heacock
Keyword(s):  
Acetic Anhydride ◽  
Sodium Borohydride ◽  
Silver Oxide ◽  
Potassium Iodate ◽  
Sodium Hydrosulfite

2-Methyladrenochrome and 1-ethyl-2-methylnoradrenochrome have been prepared by oxidation of 3,4-dihydroxyephedrine and 3,4-dihydroxyhomoephedrine with silver oxide. The corresponding 7-iodoaminochromes were obtained when the oxidations were carried out with potassium iodate. The expected 3,5,6-triacetoxyindoles were formed by treatment of these aminochromes with acetic anhydride and pyridine and the corresponding 5,6-dihydroxyindoles (isolated as their diacetyl derivatives) were obtained by reduction of the aminochromes with sodium borohydride or sodium hydrosulfite. An improved procedure for the synthesis of 3,4-dihydroxyephedrine (α-methyladrenaline) is also described.

Cu(II)/sodium borohydride-based electrocatalytic system for reduction and dyeing of indigo

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Xiaoyan Li ◽  
Zhihui Zhang ◽  
Jiming Yao ◽  
MengQian Wang ◽  
Na Yang
Keyword(s):  
Sodium Borohydride ◽  
Sewage Treatment ◽  
Integrated Analysis ◽  
Borohydride Reduction ◽  
Electrocatalytic Reduction ◽  
Content Type ◽  
Dyeing Performance ◽  
Sodium Hydrosulfite ◽  
Reduction System ◽  
Sodium Borohydride Reduction

Purpose To improve the problems as the heavy burden of sewage treatment and environmental pollution caused by the traditional sodium hydrosulfite reduction dyeing of indigo, this study aims to carry out the direct electrochemical reduction dyeing for indigo with the eco-friendly Cu(II)/sodium borohydride reduction system under normal temperature and pressure conditions. Design/methodology/approach The electrochemical behavior of Cu(II)/sodium borohydride reduction system was investigated by cyclic voltammetry. And, the dyeing performance of the Cu(II)/sodium borohydride reduction system was developed by optimizing the concentration of copper sulfate in the anode electrolyte, applied voltage and reduction time via single-factor and orthogonal integrated analysis. Findings The dyeing performance of the Cu(II)/sodium borohydride reduction system is superior to that of the traditional reduction dyeing with sodium hydrosulfite. In the case of the optimized condition, the soaping fastness and dry/wet rubbing fastness of the dyed fabric in the two reduction dyeing processes were basically comparable, the K/S value of electrocatalytic reduction of indigo by Cu(II)/NaBH4 is 11.81, which is higher than that obtained by traditional sodium hydrosulfite reduction dyeing of indigo. Originality/value The innovative electrocatalytic reduction system applied herein uses sodium borohydride as the hydrogen source combined with Cu(II) complex as the catalyst, which can serve as a medium for electron transfer and active the dye molecule to make it easier to be reduced. The electrochemical dyeing strategy presented here provides a new idea to improve the reduction dyeing performance of indigo by sodium borohydride.

THE PREPARATION OF 9-HYDROXYPYRAZOLO[3,4-b]QUINOLINES

1966 ◽  
Vol 44 (17) ◽  
pp. 2009-2014 ◽  
Author(s):  
R. T. Coutts ◽  
J. B. Edwards
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Hydrazine Hydrate ◽  
Sodium Borohydride ◽  
Sodium Acetate ◽  
The Other ◽  
Reduction Product ◽  
Type I

4-(2-Nitrobenzylidene)-2-pyrazolin-5-ones (I) were best prepared by heating o-nitrobenzaldehyde and 2-pyrazolin-5-ones in acetic anhydride containing fused sodium acetate (cf. Erlenmeyer azlactone synthesis). Pyrazolones of type I were reductively cyclized with cyclohexene and palladium–charcoal, and gave 3a,4,9,9a-tetrahydro-9-hydroxy-1H-pyrazolo-[3,4-b]quinolines (II) which, as expected, were amphoteric compounds. Of the three other methods of reduction used in this study, two (zinc and acetic acid; sodium borohydride and palladium–charcoal) were capable of producing pyrazoloquinolines, but were less reliable. The other method employed (hydrazine hydrate and palladium–charcoal) caused degradation of the pyrazolone molecule in the two cases examined, and in both, bis(2-aminobenzylidene) hydrazine (V) was the reduction product isolated.

Chromatographic analysis of methyl ethers of 2-amino-2-deoxy-D-glucopyranose

1969 ◽  
Vol 47 (21) ◽  
pp. 4091-4093 ◽  
Author(s):  
M. B. Perry ◽  
Ann C. Webb
Keyword(s):  
Liquid Chromatography ◽  
Acetic Anhydride ◽  
Paper Chromatography ◽  
Methyl Ether ◽  
Sodium Borohydride ◽  
Chromatographic Analysis ◽  
Gas Liquid Chromatography ◽  
Derivatives Of

The mono-, di-, and tri-O-methyl ether derivatives of 2-amino-2-deoxy-D-glucopyranose have been analyzed by gas–liquid chromatography of their fully acetylated 2-acetamido-2-deoxy-D-glucitol derivatives which were prepared from the glycoses by reduction with sodium borohydride followed by acetylation with acetic anhydride. The methyl ethers of 2-amino-2-deoxy-D-glucopyranose were also characterized by degradation with ninhydrin to the corresponding methyl ether derivatives of D-arabinose which were identified by paper chromatography.

scholarly journals INVESTIGATION OF INDIGO DYEING USING SODIUM BOROHYDRIDE AS REDUCING AGENT

2017 ◽  
Vol 5 ◽  
pp. 1061-1063
Author(s):  
Banu YeĹźim Buyukakinci ◽  
Nihal Sokmen
Keyword(s):  
Cotton Fabric ◽  
Sodium Borohydride ◽  
Reducing Agent ◽  
Fastness Properties ◽  
Sodium Hydrosulfite ◽  
Color Yield ◽  
The World ◽  
Indigo Dyeing ◽  
Blue Jeans ◽  
Textile Sector

Indigo, one of the oldest dyes, has a very important role for the textile sector. It is primarily used to dye cotton clothes, and blue jeans and over one billion pairs of jeans around the world are dyed blue with indigo. Although Sodium Hydrosulfite (Na2S2O4) is used as a reducing agent in most indigo dyeing processes, it is environmentally unfavorable because of the resultant contaminated toxic wastewater. In addition, the color fastnesses of dyed samples using Na2S2O4 as reducing agent are not good enough.In the present paper sodium borohydride (NaBH4) were used as ecologically safe reduction systems for the indigo dyeing of cotton fabric. After dyeing processes, the color yield and fastnesses according to washing and rubbing were measured, and results were compared.It was found when NaBH4 was used as reducing agent instead of Na2S2O4, the color yield and the fastness properties of the dyed samples improved.

ipso Nitration. XXIII. Reactions of cyclohexadiene adducts from nitration of 4-ethyltoluene in acetic anhydride

1981 ◽  
Vol 59 (15) ◽  
pp. 2314-2327 ◽  
Author(s):  
Alfred Fischer ◽  
George N. Henderson
Keyword(s):  
Sulfuric Acid ◽  
Acetic Anhydride ◽  
Methyl Iodide ◽  
Methyl Ether ◽  
Potassium Hydroxide ◽  
Silver Oxide ◽  
Aluminum Hydride ◽  
Trifluoroacetic Anhydride ◽  
Aqueous Methanol

The diastereoisomers of 4-ethyl-1-methyl-4-nitrocyclohexa-2,5-dienyl acetate (1) and 1-ethyl-4-methyl-4-nitrocyclohexa-2,5-dienyl acetate (2) are stereospecifically reduced to the corresponding nitrocyclohexadienols with aluminum hydride. Each dienol is stereospecifically methylated to the corresponding methyl ether with methyl iodide, silver oxide, and potassium hydroxide. Acid-catalysed solvolysis of the acetates 1 and 2 results in the substitution of the acetate moiety by other nucleophiles and these reactions are not stereospecific. The products of rearomatization of dienyl acetates, dienols, and dienyl methyl ethers depend on the acidity and ionizing power of the solvents and are readily explained in terms of reactions involving a nitrocyclohexadienyl cation or acetoxy- (hydroxy-, methoxy-)cyclohexadienyl cation as key intermediates. In the 4-acetoxy-4-alkylcyclohexadienyl cation 1,2-migration of the acetoxyl group is more rapid than alkyl migration, but 1,2-alkyl migration is faster than migration of the hydroxyl or methoxyl groups in the corresponding cations. 1-Ethyl-4-methoxy-4-methylcyclohexa-2,5-dien-1-ol and 4-ethyl-3-nitrotoluene are significant minor products in the solvolysis of 1-ethyl-4-methyl-4-nitrocyclohexa-2,5-dien-1-ol in aqueous methanol. Nitration of p-ethyltoluene in the presence of sulfuric acid or in trifluoroacetic anhydride gives a mixture of 4-ethyl-2-nitro- and 4-ethyl-3-nitrotoluene in a 2:1 ratio.

Convenient synthesis of 3-amino-3-deoxy-D-ribose

1968 ◽  
Vol 46 (9) ◽  
pp. 1586-1589 ◽  
Author(s):  
Walter Sowa
Keyword(s):  
Acetic Anhydride ◽  
Dimethyl Sulfoxide ◽  
Sodium Borohydride ◽  
Lithium Aluminium Hydride ◽  
Lithium Aluminium ◽  
Convenient Synthesis ◽  
Sugar Derivative

3-Amino-3-deoxy-D-ribose and D-ribose were prepared from a derivative of D-xylose. 1,2-O-Isopropylidene-5-O-triphenylmethyl-α-D-xylofuranose (2) was oxidized by dimethyl sulfoxide – acetic anhydride to 1,2-O-isopropylidene-5-O-triphenylmethyl-α-D-erythro-pentofuranos-3-ulose (3). The oxime (4) of this 3-keto sugar derivative was reduced with lithium aluminium hydride to 3-amino-3-deoxy-1,2-O-isopropylidene-5-O-triphenylmethyl-α-D-ribofuranose (5), isolated as the acetamido derivative (6). Hydrolysis yielded 3-amino-3-deoxy-D-ribose hydrochloride. 3 was reduced by sodium borohydride to 1,2-O-isopropylidene-5-O-triphenylmethyl-α-D-ribofuranose (7), which yielded D-ribose on hydrolysis.

Synthesis and Estrogenic Activity Screening of Some 6,9-Disubstituted Estradiol Derivatives

2005 ◽  
Vol 70 (4) ◽  
pp. 479-486 ◽  
Author(s):  
Marija N. Sakač ◽  
Katarina M. Penov Gaši ◽  
Mirjana Popsavin ◽  
Evgenija A. Djurendić ◽  
Silvana Andrić ◽  
...  
Keyword(s):  
Acetic Anhydride ◽  
Sodium Borohydride ◽  
Thionyl Chloride ◽  
Estrogenic Activity ◽  
Chromium Vi ◽  
Antiestrogenic Activity ◽  
Estradiol Derivatives ◽  
Biological Tests ◽  
Activity Screening

Oxidation of estradiol dipropionate (1) with chromium(VI) oxide-3,5-dimethylpyrazole complex yielded 9α-hydroxy-6-oxoestra-1,3,5(10)-triene-3,17β-diyl dipropionate (2) and 6-oxoestra-1,3,5(10)-triene-3,17β-diyl dipropionate (3). Dehydration of compound 2 with phosphorus(V) oxide or acetic anhydride gave 6-oxoestra-1,3,5(10),9(11)-tetraene-3,17β-diyl dipropionate (5). Reduction of compounds 2 and 5 with sodium borohydride afforded 3,6β,9α-trihydroxyestra-1,3,5(10)-triene-17β-yl propionate (4) and 3,6β-dihydroxyestra-1,3,5(10),9(11)-tetraene-17β-yl propionate (6), respectively. The action of thionyl chloride on compound 2 yielded 6-hydroxyestra-1,3,5(10),6,8-pentaene-3,17β-diyl dipropionate (7). Biological tests in vivo of these compounds showed a moderate antiestrogenic activity of compound 4.

Polybenzoate und -acetate des Phorbols und Phorbol-3-ols und funktionelle Derivate der Allylgruppierung des Phorbols

1968 ◽  
Vol 23 (11) ◽  
pp. 1430-1443 ◽  
Author(s):  
Hans Ulrich Schairer ◽  
Heinz Walter Thielmann ◽  
Michael Gschwendt ◽  
Gert Kreibich ◽  
Rainer Schmidt ◽  
...  
Keyword(s):  
Acetic Anhydride ◽  
Sodium Borohydride ◽  
Phorbol Esters ◽  
Allylic Alcohol ◽  
Hydroxyl Groups ◽  
Alcohol Group ◽  
Toluene Sulfonic Acid ◽  
Sodium Borohydride Reduction ◽  
Acetyl Migration ◽  
Tertiary Hydroxyl

Base catalysed transesterification of phorbol-12,13,20-tribenzoate yields phorbol-12,13-dibenzoate. By base catalysed transesterification of phorbol-pentaacetate phorbol-9,12,13-triacetate is obtained. This can be re-acetylated to give phorbol-9,12,13,20-tetraacetate which is also obtained by treatment of phorbol-12,13,20-triacetate with acetic anhydride/p-toluene-sulfonic acid.Reduction of phorbol-12,13,20-triacetate with LiAlH4 yields phorbol-3-ol which reduces Fehling's and Tollen's reagent. Reduction of the 3-keto group alone can be accomplished with sodium borohydride. From all phorbol-esters investigated only in phorbol-pentaacetate an acetyl migration is observed during the sodium borohydride reduction leading to phorbol-3-ol-3,9,12,13,20-pentaacetate. By these findings those two tertiary hydroxyl groups of phorbol which are not acetylated with acetic anhydride/pyridine at room temperature were further characterized.Oxidation of phorbol-12,13-diacetate with activated manganese dioxide yields phorbol-20-al-12,13-diacetate. By evaluation of nmr-spectra of this aldehyde and of some of its derivatives as well as of the epoxide of phorbol-12,13-diacetate and of 6-oxo-7-hydroxy- and 6,7-diacetoxy-20-nor-phorbol-12,13-diacetate the sequence of C-atoms around the allylic alcohol group of phorbol is further characterized.

Morphological Observations on the Granule Types in Rabbit Extra-Adrenal Chromaffin Cells.

1975 ◽  
Vol 33 ◽  
pp. 318-319
Author(s):  
Joe A. Mascorro ◽  
Robert D. Yates
Keyword(s):  
Chromaffin Cells ◽  
Sodium Phosphate ◽  
Ganglion Cells ◽  
Ultrastructural Level ◽  
Osmic Acid ◽  
Adrenal Chromaffin Cells ◽  
Potassium Iodate ◽  
Perfusion Fluid ◽  
New Zealand White Rabbits ◽  
Adrenal Chromaffin

Extra-adrenal chromaffin organs (abdominal paraganglia) constitute rich sources of catecholamines. It is believed that these bodies contain norepinephrine exclusively. However, the present workers recently observed epinephrine type granules in para- ganglion cells. This report investigates catecholamine containing granules in rabbit paraganglia at the ultrastructural level.New Zealand white rabbits (150-170 grams) were anesthetized with 50 mg/kg Nembutal (IP) and perfused with 3% glutaraldehyde buffered with 0.2M sodium phosphate, pH 7.3. The retroperitoneal tissue blocks were removed and placed in perfusion fluid for 4 hours. The abdominal paraganglia were dissected from the blocks, diced, washed in phosphate buffer and fixed in 1% osmic acid buffered with phosphate. In other animals, the glutaraldehyde perfused tissue blocks were immersed for 1 hour in 3% glutaraldehyde/2.5% potassium iodate buffered as before. The paraganglia were then diced, separated into two vials and washed in the buffer. A portion of this tissue received osmic acid fixation.

Melatonin reduces high levels of lipid peroxidation induced by potassium iodate in porcine thyroid

2019 ◽  
pp. 1-7 ◽  
Author(s):  
Paulina Iwan ◽  
Jan Stepniak ◽  
Malgorzata Karbownik-Lewinska
Keyword(s):  
Lipid Peroxidation ◽  
Oxidative Damage ◽  
Membrane Lipids ◽  
Chemical Properties ◽  
Iodine Concentration ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Protective Effects ◽  
Potassium Iodate ◽  
Hormone Synthesis

Abstract. Iodine is essential for thyroid hormone synthesis. Under normal iodine supply, calculated physiological iodine concentration in the thyroid is approx. 9 mM. Either potassium iodide (KI) or potassium iodate (KIO3) are used in iodine prophylaxis. KI is confirmed as absolutely safe. KIO3 possesses chemical properties suggesting its potential toxicity. Melatonin (N-acetyl-5-methoxytryptamine) is an effective antioxidant and free radical scavenger. Study aims: to evaluate potential protective effects of melatonin against oxidative damage to membrane lipids (lipid peroxidation, LPO) induced by KI or KIO3 in porcine thyroid. Homogenates of twenty four (24) thyroids were incubated in presence of either KI or KIO3 without/with melatonin (5 mM). As melatonin was not effective against KI-induced LPO, in the next step only KIO3 was used. Homogenates were incubated in presence of KIO3 (200; 100; 50; 25; 20; 15; 10; 7.5; 5.0; 2.5; 1.25 mM) without/with melatonin or 17ß-estradiol. Five experiments were performed with different concentrations of melatonin (5.0; 2.5; 1.25; 1.0; 0.625 mM) and one with 17ß-estradiol (1.0 mM). Malondialdehyde + 4-hydroxyalkenals (MDA + 4-HDA) concentration (LPO index) was measured spectrophotometrically. KIO3 increased LPO with the strongest damaging effect (MDA + 4-HDA level: ≈1.28 nmol/mg protein, p < 0.05) revealed at concentrations of around 15 mM, thus corresponding to physiological iodine concentrations in the thyroid. Melatonin reduced LPO (MDA + 4-HDA levels: from ≈0.97 to ≈0,76 and from ≈0,64 to ≈0,49 nmol/mg protein, p < 0.05) induced by KIO3 at concentrations of 10 mM or 7.5 mM. Conclusion: Melatonin can reduce very strong oxidative damage to membrane lipids caused by KIO3 used in doses resulting in physiological iodine concentrations in the thyroid.

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