A new chemical precursor system to the YBa2Cu3O7–xsuperconductor using acetic acid and 1,3-bis(dimethylamino)propan-2-ol (bdmapH), isolation and characterization of a polynuclear copper(II) complex [Cu4(OAc)6(bdmap)2(H2O)6]nwith a two-dimensional hydrogen-bonded network

1992 ◽  
pp. 1594-1596 ◽  
Author(s):  
Suning Wang ◽  
Karen D. L. Smith ◽  
Zhen Pang ◽  
Michael J. Wagner
Keyword(s):  
Acetic Acid ◽  
Two Dimensional ◽  
Isolation And Characterization ◽  
Hydrogen Bonded

Nine- and Eight-Vertex Polyhedral Dicarbaborane Chemistry: New arachno and hypho Dicarbaboranes from arachno-4,5-C2B7H13: Isolation and Characterization of the [arachno-4,5-C2B7H12]- and [hypho-7,8-C2B6H13]- Anions, and of the Neutral Ligand Derivatives exo-6-(MeNC)-arachno-4,5-C2B7H11 and exo-5-L-hypho-4,9-C2B7H13 (L = NMe3 and NEt3)

1994 ◽  
Vol 59 (7) ◽  
pp. 1584-1595 ◽  
Author(s):  
Tomáš Jelínek ◽  
Josef Holub ◽  
Bohumil Štíbr ◽  
Xavier L. R. Fontaine ◽  
John D. Kennedy
Keyword(s):  
Nmr Spectroscopy ◽  
Selective Removal ◽  
High Yield ◽  
Two Dimensional ◽  
Neutral Ligand ◽  
Tertiary Amines ◽  
Proton Sponge ◽  
H Nmr ◽  
Isolation And Characterization

Deprotonation of neutral arachno-4,5-C2B7H13 (1) either with 1, 8-(NMe2)2C10H6 (proton sponge, PS) or with a mixture of aqueous K2CO3 and [NMe4]Cl leads to the isolation in high yield of the [arachno-4,5-C2B7H12]- anion (2). Isostructural with this anion is the ligand derivative exo-6-(MeNC)-arachno-4,5-C2B7H11 (3), which is prepared in 20% yield from the reaction between arachno-4,5-C2B7H13 and MeNC in dichloromethane. Under comparable conditions compound 1 with tertiary amines gives the first representatives of the nine-vertex hypho family of dicarbaboranes, the ligand derivatives exo-5-(NR3)-hypho-4,9-C2B7H13 (4a and 4b, where R = Me and Et, respectively) in moderate yields (20 - 55%), whereas the reaction between 1 and aqueous NaCN results in the selective removal of one boron vertex to yield the eight-vertex [hypho-7,8-C2B6H13]- anion (5) in 61% yield. All compounds isolated were characterized by 11B and 1H NMR spectroscopy, with two-dimensional and selective decoupling techniques giving unambiguous assignments.

Isolation and Characterization of Low-indole-3-acetic Acid-producing Mutants fromBradyrhizobium elkanii

2000 ◽  
Vol 64 (7) ◽  
pp. 1359-1364 ◽  
Author(s):  
Ken YAGI ◽  
Taku MATSUMOTO ◽  
Tetsuya CHUJO ◽  
Hideaki NOJIRI ◽  
Toshio OMORI ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Isolation And Characterization ◽  
Indole 3 Acetic Acid

scholarly journals The Blocked Amino-Terminal Peptide of Feather Keratin

1971 ◽  
Vol 24 (1) ◽  
pp. 179 ◽  
Author(s):  
IJ O'donnell
Keyword(s):  
Molecular Weight ◽  
Acetic Acid ◽  
Amino Groups ◽  
Amino Terminal ◽  
Acetyl Content ◽  
Electrophoretic Patterns ◽  
Isolation And Characterization ◽  
Primary Amino

Proteins extracted from reduced and carboxymethylated feather keratins (SCM-keratins) have been studied by Harrap and Woods (1964a, 1964b, 1967). They have demonstrated the presence of electrophoretic heterogeneity amongst the proteins and have obtained a molecular weight of approximately 11,000 in agreement with earlier work of Woodin (1954). There was no indication of marked heterogeneity with respect to size. Using acid hydrolysis and determination of acetic acid produced they found an acetyl content of 1 �30 molesj104 g in the rachis off owl feathers. These were thought to be attached to primary amino groups since there were no O-acetyl groups. In the present paper the isolation and characterization of the predominant, and probably sole, amino-terminal tripeptide from goose feather calamus is described. Goose feather calamus was chosen because its extracted proteins had one of the simplest electrophoretic patterns of proteins from the feathers of a number of species (Harrap and Woods 1967).

Chemical constituents of two Ecuadorian medicinal plants, Tagetes terniflora Kunth and Croton rivinifolius Kunth

2021 ◽  
Author(s):  
Alírica I Suárez ◽  
Vladimir Morocho ◽  
Vladimir Luna ◽  
Katty Castillo ◽  
Chabaco Armijos
Keyword(s):  
Medicinal Plants ◽  
Spectroscopic Analysis ◽  
Chemical Constituents ◽  
Two Dimensional ◽  
Phytochemical Study ◽  
Isolation And Characterization ◽  
Organic Extracts ◽  
Medicinal Properties ◽  
Nmr Methods

Phytochemical study of two medicinal plants from Ecuador, Tagetes terniflora Kunth, and Croton rivinifolius Kunth, led to the isolation and characterization of the major constituents present in the organic extracts obtained from these plants: 5-(4-acetoxy-1-butynil)-2,2’-bi-thiophene (1), 5-methyl-2,2’:5’,2”- terthiophene (2), patuletin (3) from Tagetes terniflora, and isocorydine (4), sweroside (5), tiliroside (6) from Croton rivinifolius. The structures of these compounds were established by spectroscopic analysis including two-dimensional NMR methods, MS, and comparison with published spectral data. They are recognized as secondary metabolites that represent the chemotaxonomy of Tagetes and Croton genera and could be responsible for the recognized medicinal properties attributed to these species. This paper deals with the first report that shows the presence of these compounds in these plants.

Fluorinated tricyclic neuroleptics with prolonged action: 3-Fluoro-8-trifluoromethyl derivatives of 10-(4-methylpiperazino)- and 10-[4-(2-hydroxyethyl)piperazino]-10,11-dihydrodibenzo-[b,f]thiepin

1981 ◽  
Vol 46 (1) ◽  
pp. 118-140 ◽  
Author(s):  
Karel Šindelář ◽  
Miroslav Ryska ◽  
Jiří Holubek ◽  
Emil Svátek ◽  
Jiřina Metyšová ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Prolonged Action ◽  
Substitution Reactions ◽  
Isolation And Characterization ◽  
Chloro Derivative ◽  
Derivatives Of ◽  
Enol Ester ◽  
Preparative Purpose ◽  
Hydroxyethyl Piperazine

A reaction of (4-fluoro-2-iodophenyl)acetic acid with 4-(trifluoromethyl)thiophenol gave the acid VIII which was cyclized with the reagent consisting from methanesulphonic acid and phosphorus pentoxide and afforded the methanesulphonic enol ester XIX. The alkaline hydrolysis resulted in 3-fluoro-8-trifluoromethyldibenzo[b,f]thiepin-10(11H)-one (XVI) which was transformed via the alcohol XXIV to the chloro derivative XXV. Substitution reactions with 1-methylpiperazine and 1-(2-hydroxyethyl)piperazine resulted in the title compounds IV and V. These products are very potent cataleptic neuroleptic agents with a prolongation of duration of the effects comparable to that of isofloxythepin and tefluthixol. A series of further synthetic experiments aimed at alternative syntheses of the acid VIII and the ketone XVI; their results were mostly not of use for preparative purpose but they led to isolation and characterization of a series of interesting heterocyclic products (XVII, XVIII, XXII, XXIII, XXIX-XXXI, XXXVI-XXXIX).

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