I use hmbcgplpndqf as routine for structural elucidation. However, some artifacts have been found in spectra.

From the above list I would use hmbcetgpl2nd if you have gradients. This is a HMBC with double low pass filter for better suppression of 1J(C,H) and it is a semi phase sensitive experiment resulting in better resolution in the carbon dimension. The processing is done by doing the 2D ft with xfb and then a magnitude calculation along the observed dimension with xf2m. In newer software there is also a version with triple low pass for even better suppression of direct correlations. Write me directly to get a copy.

I routinely use the hmbcgplpndqf. On rare occasions I get better results with the simplified hmbcgpndqf. It seems the low pass filter can now and then decrease the sensitivity and supress some multiple-bounds correlations of interest. I wonder if this has been optimized in the 2-filtering step version mentioned by Tim?

I would be interested also to hear some user feedbacks about the STAR-HMBC (hmbcacbigpl2ndqf). Looks like a useful experiment for many cases of structural elucidation.

I would recommend using hmbcgpl2ndqf for "routine" 1H-13C HMBC use, provided you have gradients. This is a simple and robust sequence and contains a 2-step low pass filter for removal of one-bond responses (as opposed to hmbcgplpndqf which contains only a single step filter). Alternatively, hmbcetgpl2nd can lead to phase-sensitive data in F1 (13C) which has the potential for better resolution, but the processing is a little more complex and for most instances of small-molecule work is probably of minimal advantage.

A couple of months back, I helped a user here to run hmbc using "hmbcgplpndqf". He is using that since then. No complaints. I guess that works fine for him.

-Ilango.

I usually use hmbcgplpndqf. Has been satisfactory for me. I'll try the IMPACT-HMBC.