Vnmrj 2.2c spectrometer software

All spectra were recorded on an Agilent VNMRS 600 NMR spectrometer using a 5 mm inverse detection cryoprobe, and with the following parameters: frequency 599.83 MHz, digital resolution 0.367 Hz/point, pulse width 3 μs (45°), acquisition time 2.7 s, relaxation delay 23.7 s, number of transients 160, zero filling up to 128 K, and exponential window function with lb 0.4. 2D-NMR spectra were recorded using standard CHEMPACK 4.1 pulse sequences (gDQCOSY, gHSQCAD, gHMBCAD) implemented in Varian VNMRJ 2.2C spectrometer software. The heteronuclear single quantum coherence spectroscopy (HSQC) experiment was optimized for ¹J_CH = 146 Hz with DEPT (distortionless enhancement by polarization transfer)-like editing and ¹³C-decoupling. The heteronuclear multiple bond correlation (HMBC) experiment was optimized for a long-range coupling of 8 Hz, and a two-step ¹J_CH filter was used (130–165 Hz). Samples were randomly allocated in the sequence run.

Agilent VNMRS 600 NMR spectrometer was used to record all NMR spectra operating at a ¹H NMR frequency of 599.83 MHz and combined with implemented in Varian VNMRJ 2.2C spectrometer software. For ¹H NMR experiments, the instrument’s parameters were adjusted to a relaxation delay = 17.95 s; pulse angle = 90°, pulse width (pw) = 6.25 μs and number of transients = 120. For 2D-NMR experiments, 45° pulse width was used within the standard CHEMPACK 4.1 pulse sequences (gDQCOSY, gHSQCAD, gHMBCAD). The heteronuclear single quantum coherence spectroscopy (HSQC) experiment was adjusted to ¹J_CH = 146 Hz with DEPT-like editing and ¹³C-decoupling during acquisition time. In addition, the heteronuclear multiple bond correlation (HMBC) experiment was optimized for a long-range coupling of 8 Hz; a two-step ¹J_CH filter was utilized (130–165 Hz).