Rubber and Thioglycolic Acid

1933 ◽  
Vol 6 (1) ◽  
pp. 71-75 ◽  
Author(s):  
Bror Holmberg
Keyword(s):  
Double Bond ◽  
Nitrous Acid ◽  
Thioglycolic Acid ◽  
Water Soluble ◽  
Limited Extent ◽  
Hydrogen Halides ◽  
Carbon Bonds ◽  
New Compounds

Abstract Based on its behavior toward halogens, hydrogen halides, nitrous acid, ozone and hydrogen, rubber has one double bond for each C 5H 8 group. One would therefore expect that it would be possible to obtain from the addition products of these substances new compounds which would throw considerable light on the constitution of rubber. With the exception of the ozonides, however, this is true only to a very limited extent, a fact which depends in part upon the almost complete lack of water-soluble derivatives suitable for further reactions. It is true that the bromide of rubber can be converted by phenols into alkali-soluble compounds, but the carbon bonds of the compounds appear to be formed not only between the components but also by a closing of the ring within the rubber skeleton. Moreover in the transformation of the bromide by triethyl phosphine cyclicization appears to take place. In view of this, the constitution of these derivatives indicates that further work with them would be to little purpose, and as a matter of fact until now almost nothing of any great interest has appeared.

Potential GABAB Receptor Antagonists. VII. The Synthesis of 2-(4-Chlorophenyl)-3-nitropropan-1-amine and Related Analogs of Baclofen

1994 ◽  
Vol 47 (8) ◽  
pp. 1441 ◽  
Author(s):  
G Abbenante ◽  
R Hughes ◽  
RH Prager
Keyword(s):  
Double Bond ◽  
Guinea Pig ◽  
Sodium Borohydride ◽  
Nitrous Acid ◽  
Gabab Receptor ◽  
Guinea Pig Ileum ◽  
Efficient Route ◽  
Gabab Receptor Antagonists ◽  
Curtius Degradation ◽  
The Michael Addition

3-Nitro-2-phenylpropan-1-amine and 2-(4-chloropenyl)-3-nitropropan-1-amine have been synthesized by the addition of nitrous acid to the corresponding trifluoroacetylaminomethylstyrenes followed by reduction of the double bond with sodium borohydride. A more general and efficient route involves the Michael addition of nitroalkane anions to methyl cinnamates followed by Curtius degradation of the corresponding acids. 2-(4-Chlorophenyl)-3-nitropropan-1-amine is a specific agonist of GABA and the GABAB receptor, with about half the activity of racemic baclofen at the isolated guinea pig ileum. Methylation or dimethylation at C3 decreases activity markedly.

scholarly journals Further Guaianolides from Amphoricarpos neumayeri ssp. murbeckii from Montenegro

2006 ◽  
Vol 61 (11) ◽  
pp. 1437-1442 ◽  
Author(s):  
Iris Djordjević ◽  
Milka Jadranin ◽  
Vlatka Vajs ◽  
Nebojša Menković ◽  
Vele Tešević ◽  
...  
Keyword(s):  
Double Bond ◽  
Aerial Parts ◽  
New Compounds

The aerial parts of Amphoricarpos neumayeri ssp. murbeckii afforded eleven guaianolides with the same relative (1αH,4β H,5αH,7αH) configuration of the basic skeleton. All of them contained a CH2OX (X = H, acetyl or isovaleroyl) group in 4α-position, typical for amphoricarpolides. Four compounds (1 - 4) were isolated before from the same species, originating from different localities. Guaianolides 5 - 11 are new compounds. Compounds 7 and 8 were epoxidized at the 10α(14)-position. Instead of the Δ11(13)-double bond, observed in all previously isolated guaianolides from the same species, the four lactones contained 11α,13-diol (8 - 10) or 11α-OH,13-chloro (11) moieties respectively.

Sensitive, Direct Procedures for Simultaneous Determinations of Iron and Copper in Serum, with Use of 2-(5-Nitro-2-Pyridylazo)-5-(N-Propyl-N-Sulfopropylamino)Phenol (Nitro-PAPS) as Ligand

1992 ◽  
Vol 38 (7) ◽  
pp. 1373-1375 ◽  
Author(s):  
S Yamashita ◽  
A Abe ◽  
A Noma
Keyword(s):  
Ascorbic Acid ◽  
Sodium Dodecyl Sulfate ◽  
Present Method ◽  
Thioglycolic Acid ◽  
Colorimetric Assay ◽  
Spectroscopic Method ◽  
Sodium Dodecyl ◽  
Disodium Salt ◽  
Water Soluble ◽  
Regression Analyses

Abstract We developed a direct, simple, and sensitive procedure for the simultaneous colorimetric assay of iron and copper in serum, using sodium dodecyl sulfate-ascorbic acid to dissociate iron and copper from transferrin and ceruloplasmin, respectively. We also use a new water-soluble reagent, 2-(5-nitro-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino)phenol disodium salt (nitro-PAPS) and thioglycolic acid to eliminate interference from copper in the measurement of iron. Within- and between-run precisions of the present method were 2.5-2.8% for iron and 1.8-4.6% for copper. The proposed method is susceptible to interference by hemoglobin and lipemia, especially for the iron assay. Linear-regression analyses of results of the proposed method with those of the bathophenanthroline method for iron and of the atomic absorption spectroscopic method for copper correlated well (r = 0.996, Sy/x = 0.73 and r = 0.959, Sy/x = 1.11, respectively).

scholarly journals Synthesis of new A-conjugated Quinolone and Spiroindole Dammaranes by the Ozonolysis of 2,3-Indolodipterocarpol

2018 ◽  
Vol 13 (5) ◽  
pp. 1934578X1801300
Author(s):  
Irina E. Smirnova ◽  
Elmira F. Khusnutdinova ◽  
Alexander N. Lobov ◽  
Oxana B. Kazakova
Keyword(s):  
Double Bond ◽  
13C Nmr ◽  
Dipolar Cycloaddition ◽  
Intramolecular Rearrangements ◽  
Efficient Access ◽  
One Step ◽  
New Compounds

An one-step and efficient access to the new dammarane A-quinolones by ozonolysis of 2,3-indolodipterocarpol at 0°C through the 1,3-dipolar cycloaddition of ozone to the C2-C3 double bond of the triterpenoid core is reported. In the case of oxidation in AcOH, two spiroindoles were identified as a result of 1,2-cycloaddition of ozone to the C2-C3 double bond with following intramolecular rearrangements of 2,3-epoxy-intermediate. The structures of four new compounds were established by 1H, 13C NMR, COSY, NOSY, HMBC and HSQC analyses.

Water-soluble rhodium(II) carboxylate adducts: Cytotoxicity of the new compounds

1996 ◽  
Vol 64 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Aparecido Ribeiro de Souza ◽  
Renato Najjar ◽  
Silvana Glikmanas ◽  
Szulim Ber Zyngier
Keyword(s):  
Water Soluble ◽  
New Compounds

Heterogeneous formation and partitioning of nitrous acid on water surfaces: dependency on the acidity

2021 ◽  
Author(s):  
Jun Zheng ◽  
Yan Ma
Keyword(s):  
Liquid Water ◽  
Nitrous Acid ◽  
Ph Value ◽  
Water Solution ◽  
Formation Rate ◽  
Water Soluble ◽  
Wet Chemistry ◽  
Water Surfaces ◽  
Heterogeneous Formation ◽  
Hydrolysis Of

<p>Hydrolysis of nitrogen dioxide (NO<sub>2</sub>) has long been recognized as a major formation path of atmospheric nitrous acid (HONO), which is regarded as a dominant hydroxyl radical (OH) source, particularly in a polluted environment. Since HONO is moderately water soluble and its solubility can be highly dependent on the acidity of the water solution, the HONO formation rate and its ensuring fate may also be affected by the acidity of the water surfaces. In this work, we investigated the hydrolysis of NO<sub>2</sub> on dilute sulfuric acid water solutions with a pH value ranging from ~3 to ~6. Both the gaseous HONO and dissolved nitrous acid solution were quantified by a wet-chemistry based HONO analyzer and ion chromatography analyses, respectively. The results showed that significant amount of HONO can participate into the aqueous phase at low acidity and as the acidity increased gas-phase HONO also increased. These results indicated that liquid water on various surfaces may both provide a reaction site for HONO formation and serve as a reservoir of HONO that can be released when the liquid water was evaporated.</p>

Photocleavage of Plasmid pBR322 DNA by Some Anionic Porphyrins

1998 ◽  
Vol 02 (04) ◽  
pp. 337-343 ◽  
Author(s):  
SHAMPA R. CHATTERJEE ◽  
T. S. SRIVASTAVA ◽  
J. P. KAMAT ◽  
T. P. A. DEVASAGAYAM
Keyword(s):  
Lipoic Acid ◽  
Plasmid Dna ◽  
Dna Cleavage ◽  
Irradiation Time ◽  
Water Soluble ◽  
Plasmid Pbr322 ◽  
Limited Extent ◽  
Strand Breaks ◽  
Single Strand Breaks ◽  
Pbr322 Dna

The water-soluble porphyrins meso-tetrakis[4-(carboxymethyleneoxy)phenyl]porphyrin ( H 2 T4CPP ), meso-tetrakis[3-(carboxymethyleneoxy)phenyl]porphyrin ( H 2 T3CPP ) and meso-tetrakis[3,4-bis(carboxymethyleneoxy)phenyl]porphyrin ( H 2 T3 , 4BCPP ) cleave plasmid pBR322 DNA to single-strand breaks (SSBs) in the presence of molecular oxygen and visible light. These porphyrins induced SSBs in DNA as a function of irradiation time as well as porphyrin concentration. Under similar conditions (10 μM or more), H 2 T3CPP showed more SSBs in DNA than the porphyrins H 2 T 4CPP and H 2 T 3,4 BCPP . The DNA cleavage was more in D 2 O -based buffer than in H 2 O buffer. In addition, this DNA cleavage was inhibited by the presence of sodium azide and lipoic acid, which are potent quenchers of singlet oxygen (1 O 2). These observations suggest the involvement of 1 O 2 in photocleavage of DNA. Further, the DNA cleavage, to a limited extent, was also inhibited by tert-butanol and mannitol, both quenchers of hydroxyl radical (· OH ), suggesting the involvement of · OH in photocleavage of DNA. Thus both 1 O 2 and · OH are involved in photocleavage of plasmid DNA by these porphyrins.

PRODUCTION AND PROPERTIES OF A POLYPHENOL OXIDASE FROM THE FUNGUS POLYPORUS VERSICOLORS

1952 ◽  
Vol 30 (1) ◽  
pp. 9-21 ◽  
Author(s):  
W. M. Dion
Keyword(s):  
Acid Solution ◽  
Ferulic Acid ◽  
Polyphenol Oxidase ◽  
Submerged Culture ◽  
Water Soluble ◽  
Oxidase System ◽  
Enzyme Action ◽  
Phenolic Substances ◽  
New Compounds

The fungus Polyporus versicolor was shown to produce an extracellular polyphenol oxidase system during growth in submerged culture. The enzyme was stable and active in acid solution, and ozidized lignin, vanillin, ferulic acid, and other phenolic substances. Vanillin and ferulic acid were converted to new compounds as a result of enzyme action, whereas lignin absorbed oxygen and appeared to become more water soluble.

Water-soluble manganese phthalocyanines

2013 ◽  
Vol 17 (08n09) ◽  
pp. 881-888 ◽  
Author(s):  
Olga Dolotova ◽  
Olga Yuzhakova ◽  
Ludmila Solovyova ◽  
Ekaterina Shevchenko ◽  
Vladimir Negrimovsky ◽  
...  
Keyword(s):  
Coordination Chemistry ◽  
Aqueous Solutions ◽  
Elemental Analysis ◽  
High Purity ◽  
Water Soluble ◽  
Metal Free ◽  
Organic Bases ◽  
New Findings ◽  
Vis Spectroscopy ◽  
New Compounds

Three new substituted manganese phthalocyanines (PcMns), wich are water-soluble, have been synthesized with good yields (70–80%) and high purity. Pyridiniummethyl- and cholinylsubstituted phthalocyanines have been obtained from the chloromethylsubstituted PcMns , while octacarboxysubstituted complex has been synthesized from metal-free octacarboxyphthalocyanine tetraanhydride. Compounds were characterized by elemental analysis and mass, IR and UV-vis spectroscopy. In general, coordination chemistry of the compounds studied is similar to this one of liposoluble PcMns but some new findings have been obtained. Three coordination forms — PcMn ( II ), PcMn ( III ) X ( X = Cl -, OAc -, …) and [ LPcMn ( III )]2 O ( L = Py , Et 3 N , …) have been obtained for all the new compounds. The equilibrium between three electronic isomers — Pc+• Mn ( I ) × L , PcMn ( II ) × nL , (n = 1, 2) and Pc-• Mn ( III ) × 2 L has been observed in PcMn aqueous solutions upon the addition of organic bases L ( Py , Et 3 N , …).

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