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Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase
Published on: December 4, 2017
Observation of O-H...N scalar coupling across a hydrogen bond in nocathiacin I
Xiaohua Stella Huang1, Xiaohong Liu, Keith L Constantine
1Bristol-Myers Squibb Pharmaceutical Research Institute, Wallingford, CT 06942, USA. xiaohua.huang@bms.com
Abstract:
We report here the observation of O-H...N hydrogen-bond (1h)J(N,OH) scalar coupling in a biologically active natural product. The intramolecular hydrogen bond between the threonine hydroxyl (Thr-OH) group and the thiazolyl nitrogen at the second thiazole ring (Thz-2) in nocathiacin I was directly detected by a 1H-15N HMBC NMR experiment. The magnitude of the scalar coupling constant (1h)J(N,OH) was accurately measured to be 1.8 +/- 0.1 Hz by a J-resolved 1H-15N HMBC experiment. By adding the O-H...N distance restraint, the 3D solution structure of nocathiacin I was refined. The structure refinement indicated that the distance between the Thr-3 hydroxyl hydrogen and the Thz-2 nitrogen is
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