The studies of tautomerism in 6-mercaptopurine derivatives by 1H–13C, 1H–15N NMR and 13C, 15N CPMAS-experimental and quantum chemical approach
✍ Scribed by Leszek Pazderski; Iwona Łakomska; Andrzej Wojtczak; Edward Szłyk; Jerzy Sitkowski; Lech Kozerski; Bohdan Kamieński; Wiktor Koźmiński; Jaromír Tousek; Radek Marek
- Publisher
- Elsevier Science
- Year
- 2006
- Tongue
- English
- Weight
- 233 KB
- Volume
- 785
- Category
- Article
- ISSN
- 0022-2860
No coin nor oath required. For personal study only.
📜 SIMILAR VOLUMES
## Abstract Phenazopyridine hydrochloride (**1**), a drug in clinical use for many decades, and some derivatives were studied by one‐ and two‐dimensional ^1^H, ^13^C and ^15^N NMR methodology. The assignments, combined with DFT calculations, reveal that the preferred protonation site of the drug is
## REFERENCE DATA carbons, for various substituent groups and positions were carried out by gated decoupling with NOE. ## RESULTS AND DISCUSSION The I3C NMR chemical shifts of the compounds are shown in Tables 123; 'J(CH) and long-range coupling constants of 2, 9, 13 and 18, measured by gated d
The tautomerism and isomerism of triazoles make the structure analysis of such compounds a difficult problem, and in the case of several nitrotriazoles a detailed structure assignment had been lacking up to now. Supported by selected compounds, a deÐnite structure determination of ten nitrotriazoles
A considerable degree of variability exists in the way that LH, ~3C and ~SN chemical shifts are reported and referenced for biomolecules. In this article we explore some of the reasons for this situation and propose guidelines for future chemical shift referencing and for conversion from many common
## Abstract ^1^H, ^13^C, and ^15^N NMR chemical shifts for pyridazines 4–22 were measured using 1D and 2D NMR spectroscopic methods including ^1^H^1^H gDQCOSY, ^1^H^13^C gHMQC, ^1^H^13^C gHMBC, and ^1^H^15^N CIGAR–HMBC experiments. Copyright © 2010 John Wiley & Sons, Ltd.