TOCSY ID, selective

As an example the three subspectra of a carbohydrate 1 (peracetylated triglucose) obtained with the modified pulse sequence I and with the frequencies of the selective 180° pulses adjusted to the frequencies of the three anomeric protons lA, IB and 1C are shown in fig. 3(b). One of these spectra is compared with the corresponding spectrum measured within exactly the same total measuring time with the basic single selective ID TOCSY experiment (fig. 3(a)). 

An alternative to using selective pulses in selective ID TOCSY has been proposed [52]. The frequency selection is instead accomplished by using a homonuclear ( H) chemical shift selective filter (CSSF) [53, 54]. The chemical shift filter for frequency selection consists of a non-selective 90° pulse which is set at the frequency of the selected signal, and a systematic increment of the chemical shift evolution between this pulse and the... 

Doubly selective ID-TOCSY experiments have been proposed to specifically transfer in-phase magnetization from two designated spins [57, 58]. This transfer will only take place if the two spins are connected by a scalar coupling. This method is achieved by using a double-selective spin-lock after the selective excitation of transverse magnetization of a desired spin. The doubly selective spin-lock can be obtained by using cosine-modulated... 

Selective ID NOE Experiment (1D-N0ESY) and Selective ID TOCSY Experiment... 

If we start with I, for example, in a selective ID TOCSY, it will evolve in the spin lock to give ... 

Figure 7-24 Comparison spectra Selective ID-TOCSY (bottom), 2D-TOCSY trace (middle), and HSQC-TOCSY trace (top).

Figure 5.72. Zero-quantum interference in selective ID TOCSY spectra, (a) Partial spectmm and the corresponding regions of ID TOCSY recorded with 80-ms DIPSI-2 (b) without zero-quantum suppression and c) with the zero-quantum dephasing scheme shown in Fig. 5.74 employing adiabatic smoothed CHIRP pulses with 40 kHz sweep widths and durations of IS and 10 ms.

Figure 8.45. A general scheme for implementing the doubly selective ID TOCSY-NOESY experiment for observing NOEs originating from hidden resonances. The selectivity of the 180° pulses may be optimised independently for the two target resonances 1 and 2.

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