2443-31-4

Upstream product

• 67809-83-0 S-nitroso-N-acetylpenicillamine 
• 51-35-4 3-hydroxy-dl-proline 
• 2584-71-6 cis-hydroxy-D-proline 
• 80-11-5 N-methyl-N-nitrosotoluene-p-sulfonamide 
• 41051-51-8 2-ethoxyethyl nitrite 
• 51-35-4 4R-4-hydroxyproline 

Relevant academic research and scientific papers

(4R)-4-Hydroxy-1-nitroso-l-proline: synthesis, X-ray structure, ab initio and conformational calculations

4-Hydroxy-l-proline, an amino acid, an important component of collagen, was transformed into its N-nitroso-derivative, (4R)-4-hydroxy-1-nitroso-l-proline, 1 by butylnitrite in the acidic medium. The structure is a cyclic hydroxy-N-nitrosoacid with the carboxyl and hydroxyl groups trans to each other. The carboxyl group is in the syn-conformation. In the structure, the neutral molecules are connected via classical intermolecular O-H?O hydrogen bonds involving the hydroxyl and carboxyl groups [O?O=2.6251(14) ?], and form chains along the a-axis direction. The chains are linked into sheets via O-H?O hydrogen bond, [O?O=2.6813(15) ?] with participation of oxygen atom of nitroso group. Ab initio calculations based on density functional theory at the B3LYP/6-311++G(d, p) level of theory were performed to analyze the influence of 4-hydroxy-l-proline (Hyp) nitrosation on the conformation of the synthesized N-nitroso-compound. The geometry optimization of 1 and initial 4-hydroxy-l-proline was carried out in the gas phase and in solution using the polarizable continuum model. The single-point calculation was performed for the crystal structure of 1. The most stable conformer of 1 is observed in an aqueous solution. In this state, the pyrrolidine ring adopts an envelope conformation, which is also maintained in the gas phase. The twisted conformation of the pyrrolidine ring is present in all states of Hyp and in the crystal structure of 1. In 1 the interchange of five-membered ring conformation in solution and in the gas phase in comparison with the crystal is accompanied by an increase of the dipole moment of the molecule, which is maximal in solution.

Bismuth chloride-sodium nitrite: A novel reagent for chemoselective N-nitrosation

Bismuth(III) chloride-sodium nitrite was used as a mild and efficient reagent for N-nitrosation of various tetrazoles, secondary amines, and amides under ambient conditions. Nitrosation took place chemoselectively at the nitrogen atom, giving corresponding N-nitroso derivatives in good to excellent yield. Copyright Taylor & Francis Group, LLC.

Dinitrogen tetroxide-impregnated charcoal (N2O 4/charcoal): Selective nitrosation of amines, amides, ureas, and thiols

Efficient N-nitrosation of amines, amides, and ureas, and also S-nitrosation of thiols were performed with dinitrogen tetroxide impregnated on activated charcoal (N2O4/charcoal) in CH 2Cl2 at room temperature. High selectivity was observed for N-nitrosation of dialkyl amines, N-alkylamides and N-alkylureas. Dealkylation and N-nitrosation of trialkylamines were also performed by this reagent. Copyright Taylor & Francis, Inc.

Selective N-nitrosation of amines, N-alkylamides and N-alkylureas by N2O4 supported on cross-linked polyvinylpyrrolidone (PVP-N2O4)

N2O4 was supported on the cross-linked polyvinylpyrrolidone (PVP) to afford a solid, stable and recyclable nitrosating agent. This reagent shows excellent selectivity for N-nitrosation of dialkyl amines in the presence of diaryl-, arylalkyl-, trialkylamines and also for secondary amides in dichloromethane at room temperature under mild and heterogeneous conditions. Also N-nitroso-N-alkyl amides can be selectively prepared in the presence of primary amides and N-phenylamides under similar reaction conditions. Selective N-nitrosation or dealkylation and N-nitrosation of tertiary amines can also be performed by this reagent.

Trichloroisocyanuric acid/NaNo2 as a novel heterogeneous system for the N-nitrosation of N,N-dialkylamines under mild conditions

A combination of trichloroisocyanuric acid and sodium nitrite in the presence of wet SiO2 was used as an effective nitrosating agent for the nitrosation of N,N-dialkyl amines to their corresponding nitroso derivatives under mild and heterogeneous conditions in moderate to excellent yields.

Reactivity of nitrogen nucleophiles towards S-nitrosopenicillamine

We report the results of a kinetic study of the reactions of a number of nitrogen nucleophiles with the nitrosothiol S-nitrosopenicillamine (SPEN). The range of nucleophiles includes primary, secondary and tertiary aliphatic amines, together with hydrazine, hydroxylamine, azide ion, ammonia, semicarbazide, thiomorpholine and S-methylcysteine. Secondary amines form N-nitrosamines quantitatively. As expected, reaction occurs via the free base forms of the nucleophiles and consequently most of the reactions take place readily only at relatively high pH. Experiments were carried out with [nucleophile] ? [RSNO], and for many reactions, plots of the first order rate constant vs. [nucleophile] were linear. For ammonia and the primary amines, however, this plot tended to level off at high [nucleophile] and an explanation is offered involving the reversible formation of an inactive RSNO-amine complex, for which there is spectral evidence, in parallel with the main reaction. For the secondary amines there is a reasonably good Broensted plot with a β value of ～0.2. The much greater reactivities of S-methylcysteine and thiomorpholine, compared to those of primary amines and morpholine respectively are consistent with initial attack at the sulfur atom, followed by an internal rearrangement. Over the whole range of nucleophiles studied there is a reasonable correlation with the Ritchie N+ parameter, and not with the Pearson n scale. Comparisons are made with the corresponding reactions of alkyl nitrites and N-methyl-N-nitrosotoluene-p-sulfonamide (MNTS).

Reactivity of Nucleophilic Nitrogen Compounds towards the Nitroso Group

We discuss the reactivity of 43 nucleophilic nitrogen compounds towards the nitroso group of N-methyl-N-nitrosotoluene-p-sulfonamide (MNTS), and in some cases with alkyl nitrites.The series of nucleophiles considered is structurally very varied, includes members exhibiting the alpha effect, and covers 8 pKa units and a range of reactivities of almost five orders of magnitude.The values of solvent isotope effects and activation parameters have been measured and throw light on the structure of the transition states involved.Reactivities do not correlate well with thebasicity of the nucleophile, largely owing to the behaviour of primary amines, ammonia and nucleophiles with an alpha effect.Application of the curve crossing model suggests a relationship with vertical ionization potentials.The relationship with Ritchie's N+ scale is discussed, and interesting correlations with the reactivities of the same nucleophiles in various other chemical processes are noted.

CHIROPTICAL PROPERTIES OF N-NITROSOPYRROLIDINES AND N-NIROSAMINO ACIDS

CD data for a variety of N-nitrosamino acids and N-nitrosopyrrolidines are presented.The effects of nitrosamino group conformation, pyrrolidine ring geometry, different perturbing substituents, and especially intramulecular H-bonding upon the n?* CD band are discussed.Stereochemical conclusions can be made with confidence in many cases, although no sector diagram, as yet published, succesfully correlates all the available chiroptical data in this series of compounds.However, a negative CD band due to the ??* transition was observed for all N-nitrosamines having the L-proline configuration at C-2, regardless of nitroso group conformation; it is suggested that this band be used whenever possible for stereochemical correlations.