79546-31-9

Usage

InChI:InChI=1/C7H8N2O2/c1-11-7(10)9-6-2-4-8-5-3-6/h2-5H,1H3,(H,8,9,10)

Upstream product

• 504-24-5 4-aminopyridine 
• 79-22-1 methyl chloroformate 
• 681-84-5 tetramethylorthosilicate 
• 124-38-9 carbon dioxide 
• 67-56-1 methanol 
• 1453-82-3 isonicotinamide 
• 4013-73-4 isonicotinoyl azide 

Downstream Products

• 98279-90-4 methyl (3-nitropyridin-4-yl)carbamate 
• 7397-68-4 1,3-dihydro-2H-imidazo[4,5-c]pyridin-2-one 

Relevant academic research and scientific papers

Synthesis of unsymmetrical urea from aryl- or pyridyl carboxamides and aminopyridines using PhI(OAc)2via in situformation of aryl- or pyridyl isocyanates

A tandem synthesis of unsymmetrical ureas (N-aryl-N′-pyridylurea andN,N′-bipyridylurea) from aryl- or pyridyl carboxamides and aminopyridinesviaHofmann rearrangement has been reported. In particular, benzamides, picolinamide, nicotinamide, and isonicotinamide generate reactive intermediate isocyanates,in situ, in the presence of PhI(OAc)2, which upon further reaction with aminopyridines form urea derivatives. As the formation of pyridylisocyanates from their corresponding carboxamidesviaHofmann rearrangement remained unexplored previously, attempts have been made to trap the isocyanates. While the three pyridylisocyanates were trapped as their corresponding carbamates, 3-pyridylisocyanate was isolated and characterized. Unlike closely related previous methods reported for urea synthesis, the current method avoids direct use of isocyanates or eliminates the use of toxic phosgene for thein situgeneration of isocyanates.

N-Aryl and N-Alkyl Carbamates from 1 Atmosphere of CO2

We have successfully isolated and characterized the zinc carbamate complex (phen)Zn(OAc)(OC(=O)NHPh) (1; phen=1,10-phenanthroline), formed as an intermediate during the Zn(OAc)2/phen-catalyzed synthesis of organic carbamates from CO2, amines, and the reusable reactant Si(OMe)4. Density functional theory calculations revealed that the direct reaction of 1 with Si(OMe)4 proceeds via a five-coordinate silicon intermediate, forming organic carbamates. Based on these results, the catalytic system was improved by using Si(OMe)4 as the reaction solvent and additives like KOMe and KF, which promote the formation of the five-coordinated silicon species. This sustainable and effective method can be used to synthesize various N-aryl and N-alkyl carbamates, including industrially important polyurethane raw materials, starting from CO2 under atmospheric pressure.

A Simple Zinc Catalyst for Carbamate Synthesis Directly from CO2

Several zinc salts were employed as catalysts for the synthesis of carbamates directly from aromatic amines, CO2, and silicate esters. Zn(OAc)2 offered the best performance among the salts tested. The addition of an N-donor ligand such as 1,10-phenanthroline increased the yield. The best catalytic performance of Zn(OAc)2 can be explained by carboxylate-assisted proton activation. The interaction between the substrate and the catalyst can be observed by chemical shifts in 1H and 15N NMR spectra. Isocyanate was a key intermediate, which was generated from amine and CO2. Silicate ester was finally converted to siloxane, which was determined by 29Si NMR. The commercially available catalyst system could be reused. The yield of isolated carbamate could reach up to 96 % with various substrates, and the catalytic reaction was amine-selective in the presence of other functional groups.

Direct synthesis of carbamate from CO2 using a task-specific ionic liquid catalyst

A superbase-derived protic ionic liquid (IL, [DBUH][OAc]) catalyst was used to directly synthesize carbamate from an amine, CO2, and a silicate ester. This IL catalyst was easily prepared using its precursors, DBU, and acetic acid. Using 10 mol% of the catalyst under a CO2 pressure of 5 MPa in acetonitrile at 150 °C, carbamate was isolated in up to 96% yield. Specifically, aliphatic and aromatic amines were activated even though aromatic amines exhibited low activities because of their low pKa values. Other functional groups in amines were barely activated, affording exclusive chemoselectivity for amine activation. Isotope labeling experiments indicated that the proton in the counter cation is crucial in the catalytic cycle to produce water. In addition, a chemical shift corresponding to a mixture of aniline and [DBUH][OAc] was observed in the 1H NMR spectrum, related to the formation of hydrogen bonds between aniline and basic acetate anions. The experimental results indicated that the designed IL catalysts require a protonated cation and a basic anion.

Photolysis and thermolysis of pyridyl carbonyl azide monolayers on single-crystal platinum

The photochemical and thermal reactivity of a number of acyl azide-substituted pyridine compounds, namely nicotinyl azide, isonicotinyl azide, picolinyl azide and dinicotinyl azide with investigated as saturated monolayers on a single-crystal Pt(111) surface in an ultrahigh vacuum chamber. Multilayers of the substrates exhibited a maximum rate of desorption at 270 K, above which, stable saturated monolayers formed as characterized by reflection-absorption infrared spectroscopy by observation of C=O and N 3 bands at 1700 cm-1, and 2100 and 1300 cm-1 respectively. The monolayers were stable up to 400 K. Photolysis of the monolayer (or heating above 400 K) results in the formation of the respective isocyanate intermediate after loss of nitrogen as evidenced by the appearance of a new infrared band at 2260 cm-1 with concomitant loss of the azide bands. The resulting isocyanate saturated monolayer is stable in absence of nucleophiles, but can be quenched with appropriate nucleophiles. Saturated monolayers of a number of acyl azide-substituted pyridine compounds, namely nicotinyl azide, isonicotinyl azide, picolinyl azide and dinicotinyl azide, were formed on single-crystal Pt(111) surfaces in a UHV chamber. These monolayers were characterized by RAIR and thermal programmed desorption. Photolysis or thermolysis of these saturated monolayers leads to the corresponding isocyanate via a Curtius rearrangement.

DOSAGE OF 4-AMINOPYRIDINE DERIVATIVES FOR TREATMENT OF CENTRAL NERVOUS SYSTEM INJURIES

The invention provides novel pyridines, pharmaceutical compositions comprising such pyridines, and the use of such compositions in treating injured mammalian nerve tissue, including but not limited to an injured spinal cord, in one embodiment, the compounds, compositions, and methods of the instant invention treat a mammalian nerve tissue injury by restoring action potential or nerve impulse conduction through a nerve tissue lesion. Significantly,in vivo application of compounds of the instant invention established, on the basis of SSEP testing, that the compounds provide longer lasting effects at lower concentrations than comparable treatment with the known agent 4-aminopyridine (4 AP).Λ''invention concerne de nouvelles pyridines, des compositions pharmaceutiques comprenant ces pyridines et l''utilisation de ces compositions dans le traitement des lésions du tissu nerveux mammifère, y compris mais non de fa?on limitative, une lésion de la moelle épinière. Dans un mode de réalisation, les composés, les compositions et les méthodes selon l''invention traitent une lésion du tissu nerveux mammifère en rétablissant le potentiel d''action ou la conduction nerveuse à travers une lésion du tissu nerveux. De manière significative, l''application in vivo de composés selon l''invention établit, sur la base d''un test de potentiel évoqué somesthésique, que les composés produisent à de faibles concentrations des effets plus durables qu''un traitement comparable à l''aide de l''agent 4-aminopyridine (4 AP) connu.

Nitropyridyl isocyanates

We hereby report the first preparation of 3-nitro-4-pyridyl isocyanate 9 and 5-nitro-2-pyridyl isocyanate 18. They were formed by Curtius rearrangement of the corresponding acyl azides 8 and 17, prepared from methyl 3-nitro-4-pyridinecarboxylate 6 via the hydrazide 7 and 5-nitro-picolinic acid 16, respectively. The substrates 6 and 16 were generated by nitration of methyl 4-pyridinecarboxylate 5 and nitration and oxidation of 2-picoline 14. 3-Nitro-4-pyridyl isocyanate 9 can be stored in dry solution and is stable at room temperature for several weeks while 5-nitro-2-pyridyl isocyanate 18 was less stable and should be used for synthetic purposes immediately.

Development of novel 4-aminopyridine derivatives as potential treatments for neurological injury and disease

The amine position of the K+ channel blocker 4-aminopyridine was functionalized to form amide, carbamate and urea derivatives in an attempt to identify novel compounds which restore conduction in injured spinal cord. Eight derivatives were tested in vitro, using a double sucrose gap chamber, for the ability to restore conduction in isolated, injured guinea pig spinal cord. The methyl, ethyl and t-butyl carbamates of 4-aminopyridine induced an increase in the post injury compound action potential. The methyl and ethyl carbamates were further tested in an in vivo model of spinal cord injury. These results represent the first time that 4-aminopyridine has been derivatized without losing its ability to restore function in injured spinal cord tissue.