Morpholine

About: Morpholine is a research topic. Over the lifetime, 5411 publications have been published within this topic receiving 51063 citations. The topic is also known as: diethylene imidoxide & diethylene oximide.

One-pot synthesis of 1,3-disubstituted allenes from 1-alkynes, aldehydes, and morpholine.

Abstract: ZnI2 has been identified as the catalyst for the one-step synthesis of allenes from terminal alkynes and aldehydes with morpholine as the base in toluene. The reaction is believed to proceed via the intermediacy of propargylic amines, which was converted to allenes by a sequential hydride transfer and β-elimination process. The reaction is applicable for both aromatic and aliphatic aldehydes. Functionalities such as halide, hydroxyl, or amine may be tolerated.

Induction of Mouse Lung Adenomas by Amines or Ureas Plus Nitrite and by N-Nitroso Compounds: Effect of Ascorbate, Gallic Acid, Thiocyanate, and Caffeine

Abstract: Lung adenomas were induced in strain A mice by chronic treatment with N-nitroso compounds (given in drinking water) and with amines or ureas in food plus NaNO2 in drinking water. We studied the effects of varying the concentrations of three N-nitroso compounds and NaNO2 concentration in the morpholine plus NaNO2 and methylurea plus NaNO2 systems. Sodium ascorbate (NaASC) at the highest level tested (11.5 or 23 g/kg food) gave 89-98% inhibition of adenoma induction by the NaNO2 plus piperazine, morpholine, and methylurea systems. In 7 groups, NaASC produced increases of 15-59% in adenoma induction by nitrosomorpholine (NM) and mononitrosopiperazine (MNP), possibly because the mice consumed more of the nitrosamine solution. Adenoma induction by morpholine plus NaNO2 was strongly inhibited by gallic acid, moderately inhibited by caffeine, and unaffected by thiocyanate (all added to the food). Gallic acid inhibited or had no effect on the action of NM and MNP. We discussed the proposal that NaASC (or perhaps gallic acid) be administered with readily nitrosatable drugs.

Photoluminescence of Tetrameric copper(I) Iodide Complexes in Solution

Abstract: The colorless complexes [Cu(py)I], and [Cu(mor)I], (py = pyridine; mor = morpholine) were shown to be photoluminescent in noncoordinating solvents such as benzene, CH2Cl2, or acetone at room temperature. The red emission ( λmax= 698 nm) of the pyridine complex in benzene is quite intense (φ= 0.04) and decays with a lifetime of τ = 0.9 X s. The red photoluminescence (λmax= 654 nm) of the morpholine complex is much weaker (φ= 0.004) and decays with τ = 0.3 X 10” s. It is suggested that the emitting state of both complexes is a metal-centered 3d94s1 excited state of Cu(I), but this state is strongly modified by copper-copper interaction in the tetramer which consists of a [CUI], cubane core.

Kinetics of S-nitrosation of thiols in nitric oxide solutions.

Abstract: The S-nitroso adducts of nitric oxide (NO) may serve as carriers of NO and play a role in cell signaling and/or cytotoxicity. A quantitative understanding of the kinetics of S-nitrosothiol formation in solutions containing NO and O2 is important for understanding these roles of S-nitroso compounds in vivo. Rates of S-nitrosation in aqueous solutions were investigated for three thiols: glutathione, N-acetylcysteine, and N-acetylpenicillamine. Nitrous anhydride (N2O3), an intermediate in the formation of nitrite from NO and O2, is the most likely NO donor for N-nitrosation of amines as well as for S-nitrosation of thiols, at physiological pH. This motivated the use of a competitive kinetics approach, in which the rates of thiol nitrosation were compared with that of a secondary amine, morpholine. The kinetic studies were carried out with known amounts of NO and O2 in solutions containing one thiol (400 microM) and morpholine (200-5700 microM) in 0.01 M phosphate buffer at pH 7.4 and 23 degrees C. It was found that disulfide formation, transnitrosation reactions, and decomposition of the S-nitrosothiols was expressed as k7[N2O3][RSH], where RSH represents the thiol. The rate constant for S-nitrosation relative to that for N2O3 hydrolysis (k4) was found to be k7/k4 = (4.15 +/- 0.28) x 10(4), (2.11 +/- 0.11) x 10(4), and (0.48 +/- 0.04) x 10(4) M-1 for glutathione, N-acetylcysteine, and N-acetylpenicillamine, respectively. The overall (observed) rates of nitrosothiol formation reflect the fact that [N2O3] varies [NO]2[O2] and that [N2O3] also depends on [RSH] and the concentration of phosphate. Using a detailed kinetic model to account for these effects, the present results could be reconciled with apparently dissimilar findings reported previously by others.