tag:blogger.com,1999:blog-3300702123878659843.post16447700707714744..comments2024-03-26T05:25:50.831-04:00Comments on University of Ottawa NMR Facility Blog: 2D EXSYGlenn Faceyhttp://www.blogger.com/profile/05146575170575279335noreply@blogger.comBlogger5125tag:blogger.com,1999:blog-3300702123878659843.post-5668875917761641162020-01-08T09:33:08.983-05:002020-01-08T09:33:08.983-05:00Bhagyawanti,
For a 13C-15N shift correlation exper...Bhagyawanti,<br />For a 13C-15N shift correlation experiment via J coupling you would require a sample double labelled in 13C and 15N. You could modify a standard hetcor experiment such as 'hxcoqf' to accommodate 15N rather than 1H and then add 1H decoupling.<br />Glenn Glenn Faceyhttps://www.blogger.com/profile/05146575170575279335noreply@blogger.comtag:blogger.com,1999:blog-3300702123878659843.post-53477510444907692462014-09-03T08:16:51.752-04:002014-09-03T08:16:51.752-04:00Hi Craig,
Thank you for the comment. Yes, I have...Hi Craig,<br /><br />Thank you for the comment. Yes, I have seen both NOESY and EXSY peaks (of opposite phase) for the same protons. See an example here<br /><br />http://u-of-o-nmr-facility.blogspot.ca/2012/01/sorting-out-noes-for-exchanging.html<br /><br />Also thanks for the info CLEAN-EXSY.<br /><br />GlennGlenn Faceyhttps://www.blogger.com/profile/05146575170575279335noreply@blogger.comtag:blogger.com,1999:blog-3300702123878659843.post-42408878558022764072014-09-01T12:04:22.946-04:002014-09-01T12:04:22.946-04:00Hello Glenn
Would I be correct then in saying tha...Hello Glenn<br /><br />Would I be correct then in saying that it is possible to see both positive and negative signals (opposite phase and in-phase wrt diagonal) for the <i><b>same</b></i> proton signals arising from NOE contacts and simultaneous slow <i><b>conformational</b></i> exchange?<br /><br />I have such a spectrum on my desk at the moment - the first example I've seen of this behaviour but it seems to be the only explanation.<br /><br />Thanks,<br />Craig.<br /><br />PS for Ricardo - there's supposed to be something called CLEAN-EXSY - here's a snippet from the Bruker documentation "Modified EXSY pulse sequences have been proposed to remove NOE effects (CLEAN-EXSY experiment) and to study protein hydration (89JACS1871)".Craighttps://www.blogger.com/profile/17986100229456924793noreply@blogger.comtag:blogger.com,1999:blog-3300702123878659843.post-70177257212314488682013-01-11T07:59:05.489-05:002013-01-11T07:59:05.489-05:00Ricardo,
Thank you for your question. AS far as ...Ricardo,<br /><br />Thank you for your question. AS far as I know there is no "filter" to discrimminate between NOE's and exchange peaks. This is not usually too much of a problem for small molecules as the exchange peaks are much stronger than the NOE peaks and of opposite phase.<br /><br />GlennGlenn Faceyhttps://www.blogger.com/profile/05146575170575279335noreply@blogger.comtag:blogger.com,1999:blog-3300702123878659843.post-90956297544961042512013-01-09T20:33:59.165-05:002013-01-09T20:33:59.165-05:00Hello Glenn
Firstly congratulations for your very...Hello Glenn<br /><br />Firstly congratulations for your very usuful and great blog. Regarding Exsy-2d experiments you said that sequence is identical to NOESy-2d. There is a kind of filter for eliminate NOE peaks?<br /><br />thanks<br /><br />RicardoAnonymoushttps://www.blogger.com/profile/06353170831235675573noreply@blogger.com