Potential antidepressants: 2-(Aminoalkoxy)biphenyls and some related ω-substituted 2-alkoxybiphenyls

1989 ◽  
Vol 54 (7) ◽  
pp. 1966-1978 ◽  
Author(s):  
Irena Červená ◽  
Jiří Holubek ◽  
Emil Svátek ◽  
Jan Metyš ◽  
Miroslav Protiva
Keyword(s):  
Dimethyl Sulfoxide ◽  
Acid Hydrolysis ◽  
Sodium Cyanide ◽  
Secondary Amines ◽  
Hydrolysis Of ◽  
Bromo Compound

Reactions of 2-hydroxybiphenyl with α,ω-dibromoalkanes gave the 2-(bromoalkoxy)biphenyls IIIa-IIId. The 2-(dimethylaminoalkoxy)biphenyls VIa and VIb were transformed via carbamates VIIa and VIIb to the secondary amines Va and Vb. Their homologues Vc and Vd were obtained from the bromo compounds IIIc and IIId by treatment with methylamine. Bromo compounds IIIa and IIIb were reacted with 1-methylpiperazine, 2-(1-piperazinyl)ethanol, 3-(1-piperazinyl)propanol, and 4-amino-1-benzylpiperidine and gave the diamines VIIIa, VIIIb, IXa, Xa, Xb, and XIa. Addition of 2-hydroxybiphenyl to acrylonitrile afforded the nitrile XIIa. The homologous nitrile XIIb was obtained from the bromo compound IIIb and sodium cyanide in dimethyl sulfoxide. Nitriles XIIa and XIIb were reduced with aluminium hydride to diamines IVb and IVc. The nitriles were also transformed to hydrochlorides of the corresponding ethyl imidates XIVa and XIVb. Their hydrolysis resulted in the esters XVa and XVb. The acid XIIIa was obtained by acid hydrolysis of the nitrile XIIa; the acid XIIIb resulted from the acid hydrolysis of the ester XVb. The imidate XIVb was transformed to the amidine XVIb and to the dihydroimidazole XVIIb. Only the amine Vc showed properties indicative of potential antidepressant.

THE SYNTHESIS OF D,L-α-AMINO-ε-HYDROXYCAPROIC ACID AND A NEW SYNTHESIS OF D,L-LYSINE

1948 ◽  
Vol 26b (4) ◽  
pp. 387-392 ◽  
Author(s):  
Roger Gaudry
Keyword(s):  
Amino Acids ◽  
Acid Hydrolysis ◽  
Hydrobromic Acid ◽  
Starting Material ◽  
New Synthesis ◽  
Strecker Synthesis ◽  
Hydrolysis Of ◽  
Bromo Compound

δ-Hydroxyvaleraldehyde, obtained by acid hydrolysis of dihydropyran, is a convenient starting material for the synthesis of D,L-lysine. Application to the aldehyde of the Bucherer modification of the Strecker synthesis for α-amino acids yields 5-δ-hydroxybutylhydantoin which is hydrolyzed into D,L-α-amino-ε-hydroxycaproic acid. D,L-Lysine is obtained from 5-δ-hydroxybutylhydantoin by bromination with hydrobromic acid into 5-δ-bromobutylhydantoin, amination of the bromo compound with ammonia, and hydrolysis of the hydantoin ring into D,L-lysine, readily isolated as the dipicrate.

Septanose Carbohydrates. III. Oxidation-Reduction Products From 1,2-3,4-Di-O-isopropylidene-α-D-glucoseptanose: Preparation of L-Idose Derivatives

1990 ◽  
Vol 43 (12) ◽  
pp. 2063 ◽  
Author(s):  
GE Driver ◽  
JD Stevens
Keyword(s):  
Acetic Anhydride ◽  
Dimethyl Sulfoxide ◽  
Acid Hydrolysis ◽  
Sodium Methoxide ◽  
Aqueous Acid ◽  
Methylmagnesium Iodide ◽  
Oxidation Reduction ◽  
Hydrolysis Of

Oxidation of 1,2:3,4-di-O-isopropylidene-α-D-glucoseptanose (1a) with dimethyl sulfoxide and acetic anhydride has yielded methylthiomethyl ether (1b), ketone (2), and a novel product (3). Reduction of (2) gave (1a) and its L-ido isomer (4a) which yielded the mono-O-isopropylidene compound (5a) on aqueous acid hydrolysis. Treatment of (5a) with acidified acetone gave (4a) and 1,2:4,5-di-O-isopropylidene-β-L- idoseptanose (7a). Reaction of (2) with methylmagnesium iodide yielded the two 5-C-methyl compounds (8) and (9). Hydrolysis of (8) and (9) gave 5-C-methyl-D-glucose (10) and 5-C-methyl-L-idose (11), respectively, as crystalline compounds which yielded crystalline pentaacetates on acetylation. Treatment of the p-toluenesulfonate (1c) with lithium benzoate in dimethylformamide gave the benzoate of (4a) and an elimination product (17). Reaction of (1c) with sodium methoxide in methanol yielded (17) and the isomeric elimination product (18).

DETERMINATION OF MICRO-AMOUNTS OF 5β-PREGNAN-3α-OL-20-ONE IN URINE USING INFRARED-SPECTROMETRY

1962 ◽  
Vol 41 (2) ◽  
pp. 234-246 ◽  
Author(s):  
H. J. van der Molen
Keyword(s):  
Infrared Spectrum ◽  
Quantitative Determination ◽  
Acid Hydrolysis ◽  
Chromatographic Separation ◽  
Pure Form ◽  
Infrared Spectrometry ◽  
Hydrolysis Of

ABSTRACT A procedure for the quantitative determination of 5β-pregnan-3α-ol-20-one in urine is described. After acid hydrolysis of the pregnanolone-conjugates in urine, the free steroids are extracted with toluene. Pregnanolone is isolated in a pure form as its acetate; after chromatographic separation of the free steroids on alumina, the fraction containing pregnanolone is acetylated and rechromatographed on alumina. Quantitative determination of the isolated pregnanolone-acetate is carried out with the aid of the infrared spectrum recorded by a micro KBr-wafermethod. The reliability of the method under various conditions is discussed under the headings, specificity, accuracy, precision and sensitivity. It is possible to determine 30–40 μg pregnanolone in a 24-hours urine portion with a precision of 25%.

Optimization of technological modes of cold acid hydrolysis of potato starch

2020 ◽  
Vol 26 (3) ◽  
pp. 222-233
Author(s):  
M. Alekseenko ◽  
V. Litvyak ◽  
A. Sysa ◽  
E. Hrabovska ◽  
O. Galenko
Keyword(s):  
Acid Hydrolysis ◽  
Potato Starch ◽  
Hydrolysis Of

FLOWTHROUGH ACID HYDROLYSIS OF RAPESEED STALKS

2012 ◽  
Vol 11 (12) ◽  
pp. 2313-2318
Author(s):  
Theodor Malutan ◽  
Adina Elena Panzariu
Keyword(s):  
Acid Hydrolysis ◽  
Hydrolysis Of

scholarly journals Tagasaste, leucaena and paulownia: three industrial crops for energy and hemicelluloses production

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Alberto Palma ◽  
Javier Mauricio Loaiza ◽  
Manuel J. Díaz ◽  
Juan Carlos García ◽  
Inmaculada Giráldez ◽  
...  
Keyword(s):  
Activation Energy ◽  
Acid Hydrolysis ◽  
Energy Production ◽  
Combustion Process ◽  
Operating Conditions ◽  
Raw Material ◽  
Energy Of Combustion ◽  
Increasing Temperature ◽  
Hydrolysis Of ◽  
Chamaecytisus Proliferus

Abstract Background Burning fast-growing trees for energy production can be an effective alternative to coal combustion. Thus, lignocellulosic material, which can be used to obtain chemicals with a high added value, is highly abundant, easily renewed and usually inexpensive. In this work, hemicellulose extraction by acid hydrolysis of plant biomass from three different crops (Chamaecytisus proliferus, Leucaena diversifolia and Paulownia trihybrid) was modelled and the resulting solid residues were used for energy production. Results The influence of the nature of the lignocellulosic raw material and the operating conditions used to extract the hemicellulose fraction on the heat capacity and activation energy of the subsequent combustion process was examined. The heat power and the activation energy of the combustion process were found to depend markedly on the hemicellulose content of the raw material. Thus, a low content in hemicelluloses resulted in a lower increased energy yield after acid hydrolysis stage. The process was also influenced by the operating conditions of the acid hydrolysis treatment, which increased the gross calorific value (GCV) of the solid residue by 0.6–9.7% relative to the starting material. In addition, the activation energy of combustion of the acid hydrolysis residues from Chamaecytisus proliferus (Tagasaste) and Paulownia trihybrid (Paulownia) was considerably lower than that for the starting materials, the difference increasing with increasing degree of conversion as well as with increasing temperature and acid concentration in the acid hydrolysis. The activation energy of combustion of the solid residues from acid hydrolysis of tagasaste and paulownia decreased markedly with increasing degree of conversion, and also with increasing temperature and acid concentration in the acid hydrolysis treatment. No similar trend was observed in Leucaena diversifolia (Leucaena) owing to its low content in hemicelluloses. Conclusions Acid hydrolysis of tagasaste, leucaena and paulownia provided a valorizable liquor containing a large amount of hemicelluloses and a solid residue with an increased heat power amenable to efficient valorization by combustion. There are many potential applications of the hemicelluloses-rich and lignin-rich fraction, for example as multi-components of bio-based feedstocks for 3D printing, for energy and other value-added chemicals.

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