Synthesis and chemiluminescence of new derivatives of isoluminol

1987 ◽  
Vol 65 (6) ◽  
pp. 1392-1396 ◽  
Author(s):  
Alain Bélanger ◽  
Paul Brassard ◽  
Sylvie Laquerre ◽  
Yves Mérand
Keyword(s):  
Maleic Acid ◽  
Quantum Yields ◽  
Methyl Group ◽  
Derivatives Of

In an attempt to improve the sensitivity of luminescent immunoassays, we have prepared some new isoluminol, 7-(N,N-dialkylamino)-5-methyl-2,3-dihydrophthalazine-1,4-diones by means of a novel procedure involving the cycloaddition of dienamines to maleic acid derivatives. These compounds are characterized by the presence of a methyl group at C-5 and give quantum yields three to five times greater than those of the most efficient isoluminols in use at present.

scholarly journals Synthesis of New Antibiotics Derivatives by the Photocatalytic Method: A Screening Research

Catalysts ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1102
Author(s):  
Wojciech Baran ◽  
Ewa Masternak ◽  
Dominika Sapińska ◽  
Andrzej Sobczak ◽  
Ewa Adamek
Keyword(s):  
Quantum Yield ◽  
Biologically Active ◽  
Quantum Yields ◽  
Photocatalytic Process ◽  
Experimental Conditions ◽  
New Antibiotics ◽  
Photocatalytic Reactions ◽  
Kinetics Of ◽  
Derivatives Of ◽  
Uva Radiation

The aim of our study was to assess the possibility of using the photocatalytic process conducted in the presence of TiO2 to obtain new stable derivatives of antibacterial drugs. The possibility of introducing hydroxyl, chlorine, or bromide groups into antibiotics molecules was investigated. The experiments were conducted in aqueous solutions in the presence of TiO2-P25 as a photocatalyst, Cl− and Br- ions, and antibiotics belonging to eight different chemical classes. All experiments were initiated by UVa radiation. The kinetics of photocatalytic reactions and their quantum yield were determined, and the stable products were identified. All of the antibiotics used in the experiments underwent a photocatalytic transformation, and the quantum yields were in the range from 0.63 to 22.3%. The presence of Br- or FeCl3 significantly increased the efficiency of the photocatalytic process performed in the presence of TiO2, although Br- ion also acted as an inhibitor. Potentially biologically active chlorine derivatives from Trimethoprim, Metronidazole, Chloramphenicol, and bromine derivatives from Trimethoprim, Amoxicillin were obtained under experimental conditions. The potentially inactive halogen derivatives of Sulfamethoxazole and hydroxyl derivatives described in the literature were also identified.

scholarly journals Unusual Regularity in GC Retention of Simple Amino Acid Derivatives

2019 ◽  
Vol 6 (1) ◽  
pp. 3-14 ◽  
Author(s):  
Igor G. Zenkevich ◽  
Nino G. Todua ◽  
Anzor I. Mikaia
Keyword(s):  
Gas Chromatography ◽  
Retention Index ◽  
Methyl Esters ◽  
Elution Order ◽  
Alkyl Esters ◽  
Methyl Group ◽  
The Difference ◽  
Direct Use ◽  
Derivatives Of

Background: Application of simple regularities and general principles along with direct use of reference gas chromatography retention index data for reliable structure determination of compounds can be enhanced by determination of new regularities that are specific to certain structural elements. Objective: Revelation and interpretation of an anomaly in the elution order of alkyl esters of alkoxycarbonyl derivatives of glycine and alanine on standard and semi-standard non-polar phases. Method: Preliminary derivatization of amino acids to alkyl esters of N-alkoxycarbonyl analogs and interpretation of their gas chromatographic characteristics. Results: Alkyl esters of N-alkoxycarbonyl derivatives of alanine (Alkyl = C2H5, n- and iso-C3H7) elute prior to the same derivatives of glycine, despite the presence of an additional methyl group at C(2) in the molecule. Elution order is reversed for methyl esters of N-methoxycarbonyl derivatives. Conclusion: It is established that the peculiar behavior of alkyl esters of N-alkoxycarbonyl derivatives of glycine and alanine agrees with the concepts of gas chromatography and the known retention index regularities of organic compounds. A decrease of retention index values is a result of an introduction of an additional methyl group to a carbon atom connected to two polar fragments in a molecule like CH2XY. The dependence of the difference of retention index values for homologs of the types of CH3-CHXY and CH2XY vs. the total mass of fragments (X + Y) is similar to those for other sub-groups of analytes.

Darstellung und Eigenschaften von Derivaten des 4,5-Benzo-2,3-dihydro- \ ,3-diborols/ Synthesis and Properties of Derivatives of the 4,5-Benzo-2,3-dihydro-1,3-diborole

1993 ◽  
Vol 48 (1) ◽  
pp. 68-71 ◽  
Author(s):  
Hartmut Schulz ◽  
Thomas Deforth ◽  
Walter Siebert
Keyword(s):  
Sandwich Complexes ◽  
Methyl Group ◽  
H Nmr ◽  
Derivatives Of

Reactions of 1,2-bis(trimethyIstannyl)benzene (4) with bis(dichIoroboryl)methane derivatives (Cl2B)2CHR1 (R1 = H ,Me) lead to the formation of the 4,5-benzo-1,3-dichloro-2,3-dihydro-1,3-diboroles 2a,b.Substitution of chlorine in 2a,b by a methyl group using A1Me3 yields the 4,5-benzo-1,3-dimethyl-2,3-dihydro-1,3-diboroles 2c,d, of which 2c is thermally labile. Complexation of 2c,d with [(C5H5)Co(C2H4)2] did not give the expected sandwich complexes 6c,d, but the formation of the triple-decker 7d was observed. The paramagnetic 7d and the diamagnetic 7d+, obtained by oxidation with Ag+BF4-, were studied by 1H NMR .

BEZIEHUNGEN ZWISCHEN SUBSTITUTION IM RING A UND ABBAU IM STOFFWECHSEL BEI VERWANDTEN DES TESTOSTERONS

1962 ◽  
Vol 41 (4) ◽  
pp. 494-506 ◽  
Author(s):  
H. Langecker
Keyword(s):  
Double Bond ◽  
Ring System ◽  
Keto Group ◽  
Hydroxyl Group ◽  
Methyl Group ◽  
Structural Peculiarities ◽  
Metabolic Degradation ◽  
The Difference ◽  
Testosterone Metabolites ◽  
Derivatives Of

ABSTRACT Judging from the metabolites found in the urine, 1-methyl-androst-1-en-17β-ol-3-one (methenolone) and testosterone are metabolized in a different manner. For further clarification, other derivatives of testosterone with modifications in Ring A were investigated with regard to the oxidation of the 17-hydroxyl group. The production of urinary 17-ketosteroids decreased in the following sequence: testosterone; 1α-methyltestosterone and androstan-17β-ol-3-one; 1β-methyl-androstan-17β-ol-3-one; 2α-methyl-androstan-17β-ol-3-one and androst-1-en-17β-ol-3-one; 1α-methyl-androstan-17β-ol-3-one; 1-methyl-androsta-1,4-dien-17β-ol-3-one; 1,17α-dimethyl-androst-1-en-17β-ol-3-one and 1 -methyl-androst-1 -en-17β-ol-3-one (methenolone). The difference in metabolic degradation is also demonstrated in the fractionation of the urinary ketones. While after the administration of testosterone practically only hydrogenated 17-ketones are observed in the urine, the unchanged compound is still traceable in remarkable quantities after the administration of methenolone, along with minor quantities of the corresponding diketone. Testosterone-metabolites here are absent, whereas they represent the major substances present after the administration of androst-1-en-17β-ol-3-on. Following the administration of 1α-methyltestosterone only hydrogenated 17-ketones are detected which are still partly methylated. The 1-methyl-group and the Δ 1-double-bond seem to be responsible for the inhibition of the oxidation of methenolone in the 17-position. In addition, the hydrogenation of the double-bond and the reduction of the 3-keto-group are inhibited, obviously on account of the same structural peculiarities. The demethylation of methenolone is also inhibited. Any change in the steroid ring system forms a new substrate, thus producing new conditions for the enzymatic attack in the metabolic degradation.

scholarly journals Phosphoreszenzeigensch aften von Methyl-, Chlor- und Brom-Derivaten des [2.2] Paracyclophans

1987 ◽  
Vol 42 (9) ◽  
pp. 1041-1042 ◽  
Author(s):  
H. Hopf ◽  
E. Hermann
Keyword(s):  
Triplet State ◽  
Fluorescence Spectra ◽  
Heavy Atom ◽  
The Other ◽  
Quantum Yields ◽  
Heavy Atom Effect ◽  
Chloro Derivatives ◽  
Derivatives Of ◽  
Atom Effect

Phosphorescence and fluorescence spectra, quantum yields of phosphorescence and fluorescence as well as phosphorescence lifetimes have been measured of six methyl-, chloro- and bromo-derivatives of [2.2] paracyclophane in ethanol at 77 K. While the chloro-derivatives as well as dibromo-paracyclophane exhibit a normal internal heavy-atom effect behaviour the momobromo-compound shows anomalies. These possibly indicate that in the monobromo-compound an additional pathway of the radiationless deactivation of the lowest triplet state is effective which does not occur with the other compounds.

N-[2-(Pyridin-2-yl)ethyl]-derivatives of methane-, benzene- and toluenesulfonamide: prospective ligands for metal coordination

2013 ◽  
Vol 69 (11) ◽  
pp. 1397-1401 ◽  
Author(s):  
Danielle L. Jacobs ◽  
Benny C. Chan ◽  
Abby R. O'Connor
Keyword(s):  
Hydrogen Bonding ◽  
Dihedral Angles ◽  
Compound I ◽  
Torsion Angles ◽  
Methyl Group ◽  
A Value ◽  
Π Stacking ◽  
Linear Chains ◽  
Centroid Distance ◽  
Derivatives Of

The molecular and supramolecular structures are reported ofN-[2-(pyridin-2-yl)ethyl]methanesulfonamide, C8H12N2O2S, (I),N-[2-(pyridin-2-yl)ethyl]benzenesulfonamide, C13H14N2O2S, (II), andN-[2-(pyridin-2-yl)ethyl]toluenesulfonamide, C14H16N2O2S, (III). Although (II) and (III) are almost structurally identical, the N(amide)—C(ethyl)—C(ethyl)—C(pyridinyl) torsion angles for (I) and (II) are more closely comparable, with magnitudes of 175.37 (15)° for (I) and 169.04 (19)° for (II). This angle decreases dramatically with an additional methyl group in theparaposition of the sulfonamide substituent, resulting in a value of 62.9 (2)° for (III). In each of the three compounds there is an N—H...N hydrogen bond between the sulfonamide of one molecule and the pyridine N atom of a neighbor. Compound (I) forms hydrogen-bonded dimers, (II) uses its hydrogen bonding to connect supramolecular layers, and the hydrogen bonding of (III) connects linear chains to form layers. For arene-substituted (II) and (III), the different conformations afforded by the variable dihedral angles promote intermolecular π–π stacking in the benzene-substituted structure (II), but distorted intramolecular T-shaped π-stacking in the toluene-substituted structure (III), with a centroid-to-centroid distance of 4.9296 (10) Å.

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