Synthesis and Tautomerism of Substituted Pyrazolo[4,3-c]pyrazoles

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14740%2F13%3A00066252" target="_blank" >RIV/00216224:14740/13:00066252 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1002/ejoc.201300606" target="_blank" >http://dx.doi.org/10.1002/ejoc.201300606</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1002/ejoc.201300606" target="_blank" >10.1002/ejoc.201300606</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Synthesis and Tautomerism of Substituted Pyrazolo[4,3-c]pyrazoles

Popis výsledku v původním jazyce

Fused five-membered nitrogen heterocycles comprise a very important group of compounds frequently utilized in pharmaceutical applications. In this study, we report the first systematic synthesis of substituted pyrazolo[4,3-c]pyrazoles and three regio-isomers of their N-methyl derivatives. All compounds were fully characterized by using NMR spectroscopy in solution and selected compounds also by X-ray diffraction in the solid state. 1H, 13C, and 15N NMR data for all isomers were interpreted by DFT calculations of nuclear shielding constants and indirect spin-spin coupling constants. The N-methyl isomers were used in the following steps as model compounds to investigate a potential N1-H/N4-H, N2-H/N4-H, and N1-H/N5-H tautomerism of 3,6-substituted pyrazolo[4,3-c]pyrazoles by using low-temperature NMR spectroscopy. All bases were shown to occur predominantly in the N1-H/N4-H tautomeric form and the structure of minor form was governed by the substituents at positions 3 and 6.

Název v anglickém jazyce

Synthesis and Tautomerism of Substituted Pyrazolo[4,3-c]pyrazoles

Popis výsledku anglicky

Fused five-membered nitrogen heterocycles comprise a very important group of compounds frequently utilized in pharmaceutical applications. In this study, we report the first systematic synthesis of substituted pyrazolo[4,3-c]pyrazoles and three regio-isomers of their N-methyl derivatives. All compounds were fully characterized by using NMR spectroscopy in solution and selected compounds also by X-ray diffraction in the solid state. 1H, 13C, and 15N NMR data for all isomers were interpreted by DFT calculations of nuclear shielding constants and indirect spin-spin coupling constants. The N-methyl isomers were used in the following steps as model compounds to investigate a potential N1-H/N4-H, N2-H/N4-H, and N1-H/N5-H tautomerism of 3,6-substituted pyrazolo[4,3-c]pyrazoles by using low-temperature NMR spectroscopy. All bases were shown to occur predominantly in the N1-H/N4-H tautomeric form and the structure of minor form was governed by the substituents at positions 3 and 6.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

CC - Organická chemie

OECD FORD obor

—

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2013

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

European Journal of Organic Chemistry

ISSN

1434-193X

e-ISSN

—

Svazek periodika

2013

Číslo periodika v rámci svazku

30

Stát vydavatele periodika

DE - Spolková republika Německo

Počet stran výsledku

12

Strana od-do

6811-6822

Kód UT WoS článku

000328739500009

EID výsledku v databázi Scopus

—