Complete ¹H and ¹³C NMR spectral assignment of α‐ and β‐adenosine, 2′‐deoxyadenosine and their acetate derivatives

Abstract

(1)H and (13)C NMR chemical shifts of alpha- and beta-anomers of adenosine, 2'-deoxyadenosine and their acetate derivatives were completely and definitely assigned using the concerted application of one- and two-dimensional experiments (gCOSY, gNOESY, gHSQC and gHMBC). The influence of the stereochemistry of the purine base on the NMR data of the hydrogen and carbon atoms of the furanose moiety was estimated.

1H, 13C and 15N NMR assignments for N6‐isopentenyladenosine/inosine analogues

“…gs-NOESY experiments allowed the determination of the H-8 resonance. [6] In addition, H-8 resonances were assigned according to HMBC correlations between H-1 and C-8. The other observed cross-peaks fully confirm the carbon assignment ( Table 2).…”

“…The central peak of DMSO-d 6 signals (δ = 2.49 ppm for 1 H and 39.50 ppm for 13 C) were used as internal reference standard. The 15 N chemical shifts were referenced externally through the 15 N NMR spectrum of 1 M urea in DMSO-d 6 , which is a well-documented secondary reference and has a shift of δ = 77.0 ppm relative to liquid ammonia. [7] 1D acquisition parameters were as follows: 1 H spectral width of 5000 Hz and 32 K data points providing a digital resolution of ca 0.305 Hz per point, relaxation delay 2 s; 13 C spectral width of 29 412 Hz and 64 K data points providing a digital resolution of ca 0.898 Hz per point, relaxation delay 2.5 s. The experimental error in the measured 1 H-1 H coupling constants is ±0.5 Hz.…”

“…[5] We here report the complete 1 H, 13 C and 15 N NMR chemical shifts assignments of these compounds, obtained with one-(1D) and two-dimensional (2D) NMR techniques, including DEPT, COSY, NOESY, gs-HSQC and gs-HMBC, to develop an NMR adenosine database for new adenosine derivatives. [6] We focussed our attention on 15 N chemical shifts to better define the structure and conformation of the newly synthesised molecules. Despite the extreme sensitivity of the 15 …”

Chemical Constituents Identified from Fruit Body of Cordyceps bassiana and Their Anti-Inflammatory Activity

“…1B), representative redox-sensitive transcription factors inducing inflammatory gene expression (Lee et al ., 2011; Gil et al ., 2015), anti-inflammatory principle in C. bassiana was further isolated using column chromatography and HPLC. By this work, in fact, 8 compounds could be identified, including 1,9-dimethylguanine (1) (Sigel et al ., 2000), adenosine (2) (Ciuffreda et al ., 2007), uridine (3) (Bagno et al ., 2008), nicotinamide (Jung et al ., 2012), 3-methyluracil (5) (Wong et al ., 2002), 1,7-dimethylxanthine (6) (Jiang et al ., 1998), nudifloric acid (7) (Yuyama and Suzuki, 1991), and mannitol (8) (Bock and Pedersen, 1983), respectively, based on their spectroscopic data (Fig. 2B).…”

Complete assignment of the 1H and 13C NMR spectra of cis and trans isonucleoside derivatives of purine with a tetrahydropyran ring

“…[9] Recently, it has been published a complete analysis of 1 H and 13 C NMR data for α and β anomers of adenosine and 2 -deoxyadenosine that could be very useful to identify both anomers in related compounds. [10] The huge number of nucleoside analogues synthesised requires similar studies, particularly for nucleosides with modifications in the sugar moiety, that would help us to reveal general behaviours of the chemical shifts signals depending on the configuration. Here, we describe the complete 1 H and 13 C NMR assignments of two series of tetrahydropyran isonucleosides with cis (1-3) and trans (4-5) stereochemistry.…”