LYCOPODIUM ALKALOIDS: IV. REACTIONS OF α-CYANOBROMOLYCOPODINE AND ITS DERIVATIVES

1956 ◽  
Vol 34 (11) ◽  
pp. 1519-1527 ◽  
Author(s):  
L. R. C. Barclay ◽  
David B. MacLean
Keyword(s):  
Nitrogen Atom ◽  
Carbonyl Group ◽  
Lycopodium Alkaloids ◽  
Hydrolysis Of ◽  
Methylene Group

The hydrogenolysis and hydrolysis of α-cyanobromolycopodine to the secondary tricyclic base, α-des-dihydrolycopodine, is reported. The latter compound was converted to the methiodide in poor yield so that further degradations of the molecule through this derivative were not feasible. Hydride reductions of α-cyanobromolycopodine and some of its derivatives are recorded. The presence of a methylene group adjacent to the carbonyl group in lycopodine has been proved. Evidence is presented which suggests that the carbonyl group and the nitrogen atom are relatively close to one another in the molecule.

LYCOPODIUM ALKALOIDS: VIII. LYCOPODINE

1959 ◽  
Vol 37 (10) ◽  
pp. 1757-1763 ◽  
Author(s):  
D. B. MacLean ◽  
W. A. Harrison
Keyword(s):  
Nitrogen Atom ◽  
Carbonyl Group ◽  
Lycopodium Alkaloids

Information pertaining to the position of the carbonyl group relative to the nitrogen atom and to the size of one of the nitrogen rings in lycopodine has been obtained through a study of the reactions of α- and β-cyanobromolycopodine.

Methylsteroids. VII. Factors Affecting the Hydrolysis of 7α- and 11β-Acetoxylanostanes

1961 ◽  
Vol 14 (1) ◽  
pp. 48
Author(s):  
CS Barnes ◽  
BD Beilby
Keyword(s):  
Carbonyl Group ◽  
Carbonyl Groups ◽  
Factors Affecting ◽  
Steric Crowding ◽  
Methylene Groups ◽  
Rate Of Hydrolysis ◽  
Hydrolysis Of ◽  
Methylene Group

Doubly bonded methylene groups have been introduced into 7α- and 11β-acetoxylanostanes and the rate of hydrolysis compared with compounds having a hydroxy or carbonyl group at the same position as the methylene group. It was found that methylene groups facilitate hydrolysis of the hindered acetoxy groups in the same way, but not to the same extent, as carbonyl groups. It is concluded that the facilitation in each case results from a conformational disturbance, but that there is some other factor involved in carbonyl facilitation. It was not possible to demonstrate a similar effect resulting from steric crowding of substituents.

scholarly journals ALKYLATION OF TRIETHYL ESTER OF PHOSPHONOACETIC ACID AND DIETHOXYCYANOMETHYLPHOSPHONATE WITH HALOIDACETALS AND PRODUCTS OF THEIR TRANSFORMATION

2017 ◽  
Vol 60 (2) ◽  
pp. 13
Author(s):  
Valekh M. Ismailov ◽  
Niftaly N. Yusubov ◽  
Nurlana D. Sadykhova ◽  
Gezal G. Ibragimova ◽  
Iskander A. Mamedov
Keyword(s):  
Nmr Spectroscopy ◽  
Carbon Atom ◽  
Carbonyl Group ◽  
Organic Compounds ◽  
Phosphonoacetic Acid ◽  
Ir And Nmr Spectroscopy ◽  
High Reaction ◽  
Hydrolysis Of ◽  
Active Methylene ◽  
Methylene Group

The method was developed for synthesis of hard-to-reach phosphorylated aldehides with hidden carbonyl group. As compounds with active methylene group triethyl ethers of phosfonacetic acid and diethoxycianomethyl phosfonate were used at the condensation with bromo- and chloroacetals to produce the corresponding acetals. It was found that in the mentioned phosphonates the alkylation by haloid acetal occurs exceptionally on the carbon atom of active methylene group, not touching the nitrile and ester groups. The hydrolysis of obtained phosphorylated acetals led to preparation of phosphorylated aldehydes. It was found that an application of chlorinated acetals led to decreasing the yield of final products. On the basis of obtained aldehydes the corresponding hydrozones were prepared. The latter in the course of reaction undergoes the conversion occurring on the nitrile and ester groups. The high reaction activity of synthesized phosphorylated acetals was used in the further synthesis of different kind of phosphoroganic compounds.  The reaction of phosphorylated aldehydes with hydrazine led to obtaining the nitrogen and phosphor containing organic compounds. The structures of synthesized compounds were studied and proved by IR and NMR spectroscopy methods. Forcitation:                                                                                                                    Ismailov V.M., Yusubov N.N., Sadykhova N.D., Ibragimova G.G., Mamedov I.A. Alkylation of triethyl ester of phosphonoacetic acid and diethoxycyanomethylphosphonate with haloidacetals and products of their transformation. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 2. P. 13-16.

DFT study on the hydrolysis of metsulfuron-methyl: A sulfonylurea herbicide

2018 ◽  
Vol 17 (08) ◽  
pp. 1850050 ◽  
Author(s):  
Qiuhan Luo ◽  
Gang Li ◽  
Junping Xiao ◽  
Chunhui Yin ◽  
Yahui He ◽  
...  
Keyword(s):  
Free Energy ◽  
Water Molecule ◽  
Carbonyl Group ◽  
Energy Barrier ◽  
Density Functional ◽  
Free Energy Barrier ◽  
Functional Theory ◽  
Metsulfuron Methyl ◽  
Catalytic Role ◽  
Hydrolysis Of

Sulfonylureas are an important group of herbicides widely used for a range of weeds and grasses control particularly in cereals. However, some of them tend to persist for years in environments. Hydrolysis is the primary pathway for their degradation. To understand the hydrolysis behavior of sulfonylurea herbicides, the hydrolysis mechanism of metsulfuron-methyl, a typical sulfonylurea, was investigated using density functional theory (DFT) at the B3LYP/6-31[Formula: see text]G(d,p) level. The hydrolysis of metsulfuron-methyl resembles nucleophilic substitution by a water molecule attacking the carbonyl group from aryl side (pathway a) or from heterocycle side (pathway b). In the direct hydrolysis, the carbonyl group is directly attacked by one water molecule to form benzene sulfonamide or heterocyclic amine; the free energy barrier is about 52–58[Formula: see text]kcal[Formula: see text]mol[Formula: see text]. In the autocatalytic hydrolysis, with the second water molecule acting as a catalyst, the free energy barrier, which is about 43–45[Formula: see text]kcal[Formula: see text]mol[Formula: see text], is remarkably reduced by about 11[Formula: see text]kcal[Formula: see text]mol[Formula: see text]. It is obvious that water molecules play a significant catalytic role during the hydrolysis of sulfonylureas.

scholarly journals Unexpected Resistance to Base-Catalyzed Hydrolysis of Nitrogen Pyramidal Amides Based on the 7-Azabicyclic[2.2.1]heptane Scaffold

Molecules ◽  
2018 ◽  
Vol 23 (9) ◽  
pp. 2363 ◽  
Author(s):  
Diego Ocampo Gutiérrez de Velasco ◽  
Aoze Su ◽  
Luhan Zhai ◽  
Satowa Kinoshita ◽  
Yuko Otani ◽  
...  
Keyword(s):  
Nitrogen Atom ◽  
Amide Bond ◽  
Free Energies ◽  
Amide Nitrogen ◽  
Bond Rotation ◽  
Entropy Term ◽  
And Inversion ◽  
Kinetics Of ◽  
Hydrolysis Of ◽  
Amide Nitrogen Atom

Non-planar amides are usually transitional structures, that are involved in amide bond rotation and inversion of the nitrogen atom, but some ground-minimum non-planar amides have been reported. Non-planar amides are generally sensitive to water or other nucleophiles, so that the amide bond is readily cleaved. In this article, we examine the reactivity profile of the base-catalyzed hydrolysis of 7-azabicyclo[2.2.1]heptane amides, which show pyramidalization of the amide nitrogen atom, and we compare the kinetics of the base-catalyzed hydrolysis of the benzamides of 7-azabicyclo[2.2.1]heptane and related monocyclic compounds. Unexpectedly, non-planar amides based on the 7-azabicyclo[2.2.1]heptane scaffold were found to be resistant to base-catalyzed hydrolysis. The calculated Gibbs free energies were consistent with this experimental finding. The contribution of thermal corrections (entropy term, –TΔS‡) was large; the entropy term (ΔS‡) took a large negative value, indicating significant order in the transition structure, which includes solvating water molecules.

scholarly journals Use of a Hydrolytic Procedure and Spectrometric Methods in the Structure Elucidation of a Thiocarbonyl Analogue of Sildenafil Detected as an Adulterant in an Over-the-Counter Herbal Aphrodisiac

2009 ◽  
Vol 92 (5) ◽  
pp. 1336-1342 ◽  
Author(s):  
John C Reepmeyer ◽  
D Andr d'Avignon
Keyword(s):  
Dietary Supplement ◽  
Carbonyl Group ◽  
Minor Component ◽  
Pyrimidine Ring ◽  
Over The Counter ◽  
Methyl Group ◽  
Nmr Spectrometry ◽  
A Minor ◽  
Hydrolysis Of ◽  
Hydroxyethyl Group

Abstract A sildenafil-related compound was detected in an herbal dietary supplement marketed as an aphrodisiac. The compound was identified as an analogue of sildenafil in which the carbonyl group in the pyrimidine ring of sildenafil was substituted with a thiocarbonyl group, and the methyl group on the piperazine ring was substituted with a hydroxyethyl group. Based on this structure, the compound was named thiohydroxyhomosildenafil. The structure of the compound was established using HPLC/MS, UV spectrometry, electrospray ionization-MS/MS, NMR spectrometry, and a hydrolytic process. One key product of hydrolysis was 1-(2-hydroxyethyl)-piperazine; the identification of this product defined the amine portion of the compound. Another key product of hydrolysis was hydroxyhomosildenafil, generated by hydrolysis of the thiocarbonyl group to a carbonyl group (C S C O). Hydroxyhomosildenafil was detected as a minor component in the dietary supplement.

Studies on the lignin of Eucalyptus regnans F. Muell. VII. The acid hydrolysis of ethanyol lignin-A

1953 ◽  
Vol 6 (2) ◽  
pp. 156 ◽  
Author(s):  
JWT Merewether
Keyword(s):  
Hydrochloric Acid ◽  
Acid Hydrolysis ◽  
Carbonyl Group ◽  
Dilute Hydrochloric Acid ◽  
Hydroxyl Groups ◽  
Eucalyptus Regnans ◽  
Ethoxyl Group ◽  
Hydrolysis Of

Ethanol lignin-A from the ethanolysis of Eucalyptus regnans P. Muell. has been hydrolysed with dilute hydrochloric acid with the object of ascertaining whether the combined ethoxyl is present as an acetal or as ether. Hydrolysis with 12 per cent. hydrochloric acid was found to split off one ethoxyl group, while hydrolysis with 20 per cent. acid brought about complete de-ethylation. The de-ethylated ethanol lignin-A contained one carbonyl group less and two hydroxyl groups more than the original ethanol lignin-A. These results lend no support to the hypothesis that alcohol lignins are acetals, and favour the theory that the combined alkoxyl is probably present as ether.

Sur l'aptitude à l'extension du noyau pipéridique en fonction de la substitution de l'atome d'azote: réaction du diazométhane avec quelques pipéridones-4 et désamination nitreuse des aminométhyl-alcools correspondants

1971 ◽  
Vol 49 (19) ◽  
pp. 3075-3085 ◽  
Author(s):  
H. Favre ◽  
Z. Hamlet ◽  
R. Lanthier ◽  
M. Ménard
Keyword(s):  
Nitrogen Atom ◽  
Carbonyl Group ◽  
Nitrous Acid ◽  
Ring Expansion ◽  
Nucleophilic Attack ◽  
Electronic Effects ◽  
Field Effects ◽  
Benzoyl Group ◽  
La Substitution

Aptitude to ring expansion in the piperidine series, measured by the ratio of ring expanded ketone to epoxide, varies considerably according to the nitrogen atom substituent. This ratio is essentially the same in the case of the reaction of diazomethane on 4-piperidones and the nitrous acid deamination of the corresponding aminoalcohols. The values of the ratio are 0.01–0.1 for a phenylsulfonyl group, of the order 0.3–0.6 for a benzoyl group and slightly greater than 1 for a benzyl group. Electronic effects (inductive and field effects) are the cause of these differences. Parallels between the two reactions indicate that nucleophilic attack of diazomethane on the carbonyl group can lead to the ring expanded ketone and the epoxide.

Micellar Catalysis of Organic Reactions. XVII. Hydrolysis of Nitrazepam and Some N-Alkylated Derivatives

1985 ◽  
Vol 38 (7) ◽  
pp. 1037 ◽  
Author(s):  
TJ Broxton ◽  
SR Morrison
Keyword(s):  
Aqueous Solution ◽  
Nitrogen Atom ◽  
Sodium Dodecyl Sulfate ◽  
Sodium Dodecyl ◽  
Initial Attack ◽  
Amide Nitrogen ◽  
High Acid ◽  
Alkyl Derivatives ◽  
Hydrolysis Of ◽  
Amide Nitrogen Atom

Product studies for the acid catalysed hydrolysis of nitrazepam and some N-alkyl derivatives in the presence of micelles of sodium dodecyl sulfate ( sds ) have been carried out by a U.V. spectrophotometric technique. Attack of water at C2 leading to initial amide cleavage is favoured by high acid concentrations, by micelles of sds and by small R groups attached to the amide nitrogen atom. For nitrazepam, a change of mechanism from water attack at C5 (leading to initial azomethine cleavage) to water attack at C2 (leading to initial amide cleavage) was observed on transfer from water to micelles of sds . For N-benzyl nitrazepam (1d), however, no change of mechanism was detected. Initial attack of water occurred at C5 (leading to initial azomethine cleavage), both in aqueous solution and in micelles of sds.

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