scholarly journals Spectroscopic methods and theoretical studies of bromoacetic substituted derivatives of bile acids

2015 ◽  
Vol 62 (1) ◽  
Author(s):  
Tomasz Pospieszny ◽  
Hanna Koenig ◽  
Iwona Kowalczyk ◽  
Bogumił Brycki
Keyword(s):  
Bile Acids ◽  
Spectroscopic Methods ◽  
Theoretical Studies ◽  
Derivatives Of

Derivatives of isatin in aqueous solution. I. Kinetics of ring opening of Isatin-5-sulfonate

1981 ◽  
Vol 34 (2) ◽  
pp. 365 ◽  
Author(s):  
H Stunzi
Keyword(s):  
Ring Opening ◽  
Rate Of Change ◽  
Spectroscopic Methods ◽  
Ph Values ◽  
Buffer Region ◽  
Pka Value ◽  
Back Titration ◽  
Kinetics Of ◽  
Derivatives Of ◽  
Sulfonate Anion

The reactions of isatin-5-sulfonate anion (si-) which cause a hysteresis in pH titrations were studied by pH-metric and n.m.r, spectroscopic methods. Rapid alkalimetric titrations [I 0.15 M (KNO3),37�] gave the pKa value corresponding to the addition of OH- to si- [pKa(ring) 9.55]. The slow ring opening to the sulfonatoisatate dianion (sia2-) led to a drift of the pH values towards an equilibrium buffer region. Its pKa, value [pKa(eq) 3.44] corresponds to the reaction si-+H2O ↔ sia 2-+H+ Rapid back-titration gave the pKa value of the ring-opened species Hsia- [pKa(open) c. 1.3]. The rate law for the ring opening d[sia]/dt=k2 [siOH](OH)+k1*[si] was obtained from the rate of change of pH. N-Methylisatin-5-sulfonate behaves analogously.

scholarly journals Thermodynamically stable [4 + 2] cycloadducts of lanthanum-encapsulated endohedral metallofullerenes

2014 ◽  
Vol 10 ◽  
pp. 714-721 ◽  
Author(s):  
Yuta Takano ◽  
Yuki Nagashima ◽  
M Ángeles Herranz ◽  
Nazario Martín ◽  
Takeshi Akasaka
Keyword(s):  
Thermal Stability ◽  
Material Science ◽  
Molecular Structures ◽  
Spectroscopic Methods ◽  
Dynamic Nmr ◽  
The Novel ◽  
Endohedral Metallofullerenes ◽  
Derivatives Of ◽  
Paramagnetic Properties

The [4 + 2] cycloaddition of o-quinodimethanes, generated in situ from the sultine 4,5-benzo-3,6-dihydro-1,2-oxathiin 2-oxide and its derivative, to La metal-encapsulated fullerenes, La2@C80 or La@C82, afforded the novel derivatives of endohedral metallofullerenes (3a,b, 4a,b and 5b). Molecular structures of the resulting compounds were elucidated using spectroscopic methods such as MALDI–TOF mass, optical absorption, and NMR spectroscopy. The [4 + 2] adducts of La2@C80 (3a,b, and 4a,b) and La@C82 (5b), respectively, retain diamagnetic and paramagnetic properties, as confirmed by EPR spectroscopy. Dynamic NMR measurements of 4a at various temperatures demonstrated the boat-to-boat inversions of the addend. In addition, 5b revealed remarkable thermal stability in comparison with the reported [4 + 2] cycloadduct of pentamethylcyclopentadiene and La@C82 (6). These findings demonstrate the utility of sultines to afford thermodynamically stable endohedral metallofullerene derivatives for the use in material science.

scholarly journals Novel Semisynthetic Derivatives of Bile Acids as Effective Tyrosyl-DNA Phosphodiesterase 1 Inhibitors

Molecules ◽  
2018 ◽  
Vol 23 (3) ◽  
pp. 679 ◽  
Author(s):  
Oksana Salomatina ◽  
Irina Popadyuk ◽  
Alexandra Zakharenko ◽  
Olga Zakharova ◽  
Dmitriy Fadeev ◽  
...  
Keyword(s):  
Bile Acids ◽  
Derivatives Of

Some O-isopropylidene derivatives of D-ribose diethyl dithioacetal

1969 ◽  
Vol 47 (15) ◽  
pp. 2889-2891 ◽  
Author(s):  
D. G. Lance ◽  
W. A. Szarek ◽  
J. K. N. Jones
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Copper Sulfate ◽  
Spectroscopic Methods ◽  
Isopropylidene Derivatives ◽  
Derivatives Of ◽  
Nuclear Magnetic

Acetonation of D-ribose diethyl dithioacetal using anhydrous copper sulfate as catalyst gives predominantly 2,4- and 4,5-O-isopropylidene derivatives. The structures of the compounds were established by chemical and nuclear magnetic resonance spectroscopic methods.

scholarly journals Shushe Acids A-D from Ganoderma Applanatum

2017 ◽  
Vol 12 (3) ◽  
pp. 1934578X1701200
Author(s):  
Qi Luo ◽  
Yan-Jiao Zhang ◽  
Zhi-Qiang Shen ◽  
Peng Chen ◽  
Yong-Xian Cheng
Keyword(s):  
Succinic Acid ◽  
Natural Product ◽  
Gallic Acid ◽  
Spectroscopic Methods ◽  
Fruiting Bodies ◽  
Ganoderma Applanatum ◽  
Prevention And Treatment ◽  
New Compounds ◽  
Derivatives Of ◽  
Mcf 7

Ganoderma applanatum is a fungus used for the prevention and treatment of a variety of disorders in China. In the present study, four new compounds, named shushe acids A-D (1-4), were isolated from the fruiting bodies of this species. Their structures were identified on the basis of spectroscopic methods. Compounds 1-4 are all natural product hybrids composed of derivatives of gallic acid, glycerol and succinic acid. None of the four compounds showed activity against the MCF-7 cell line.

Structure and Content of Dicyclopentadiene in Ethylene Propylene Dicyclopentadiene Terpolymers

1967 ◽  
Vol 40 (2) ◽  
pp. 563-568
Author(s):  
R. J. de Kock ◽  
A. Veermans
Keyword(s):  
Double Bond ◽  
Polymer Chain ◽  
Spectroscopic Methods ◽  
Double Bonds ◽  
Model Compounds ◽  
Ethylene Propylene ◽  
Infrared Spectroscopic ◽  
Polymerization Mixture ◽  
Derivatives Of

Abstract With the aid of model compounds—derivatives of endo- and exo-dicyclopentadiene—it has been established that a) the 9, 10-double bond (the double bond in the norbornane ring) is involved in the polymerization of dicyclopentadiene with ethylene and propylene, b) dicyclopentadiene, present in the polymerization mixture in the endo-configuration, occurs in the exo-configuration in the polymer chain. The same model compounds enable the dicyclopentadiene content of ethylene propylene dicyclopentadiene terpolymers to be determined by infrared spectroscopic methods. Use is made of the 3045 cm−1 band, which is characteristic of endo-cyclic double bonds in five-membered rings.

ChemInform Abstract: Experimental and Theoretical Studies of Correlated Rotation in Tris( ortho-tolyl) Derivatives of P, As and Si.

ChemInform ◽  
2010 ◽  
Vol 24 (4) ◽  
pp. no-no
Author(s):  
J. A. S. HOWELL ◽  
M. G. PALIN ◽  
P. C. YATES ◽  
P. MCARDLE ◽  
D. CUNNINGHAM ◽  
...  
Keyword(s):  
Theoretical Studies ◽  
Derivatives Of ◽  
Experimental And Theoretical Studies

scholarly journals Synthesis, Spectroscopic and Theoretical Studies of New Quaternary N,N-Dimethyl-3-phthalimidopropylammonium Conjugates of Sterols and Bile Acids

Molecules ◽  
2014 ◽  
Vol 19 (4) ◽  
pp. 4212-4233 ◽  
Author(s):  
Bogumil Brycki ◽  
Hanna Koenig ◽  
Iwona Kowalczyk ◽  
Tomasz Pospieszny
Keyword(s):  
Bile Acids ◽  
Theoretical Studies
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