مقایسهٔ روش‌ها

	همبستگی کوانتومی منفرد ناهمگن (HSQC)	کوسی (COSY)	NOESY
حوزه	طیف‌سنجی	طیف‌سنجی	طیف‌سنجی
خانواده	Process / pipeline	Process / pipeline	Process / pipeline
سال پیدایش	1980	1976	1981
پدیدآور	Anil Kumar	Wüthrich Kurt	Richard Ernst
نوع	Heteronuclear correlation sequence	Two-dimensional pulse sequence	Two-dimensional pulse sequence
منبع بنیادین	Bodenhausen, G., & Ruben, D. J. (1981). Natural abundance nitrogen-15 NMR by enhanced heteronuclear spectroscopy. Chemical Physics Letters, 69(2), 185-189.	Aue, W. P., Bartholdi, E., & Ernst, R. R. (1976). Two-dimensional spectroscopy. Application to nuclear magnetic resonance. The Journal of Chemical Physics, 64(5), 2229-2246.	Aue, W. P., Bartholdi, E., & Ernst, R. R. (1976). Two-dimensional spectroscopy. Application to nuclear magnetic resonance. The Journal of Chemical Physics, 64(5), 2229-2246.
نام‌های دیگر	HSQC NMR, 1H-13C HSQC, heteronuclear correlation	COSY NMR, 2D COSY, 1H-1H COSY	NOE spectroscopy, 2D NOESY, NOE NMR
مرتبط	4	4	3
خلاصه	Heteronuclear Single-Quantum Coherence (HSQC) is a 2D NMR technique that correlates proton and carbon-13 (or other heteronuclei) chemical shifts through one-bond coupling constants (1JHX). Developed in the early 1980s, HSQC rapidly became the workhorse of structural chemistry because it directly maps which carbons bear which protons, providing a comprehensive view of carbon skeleton connectivity and substitution patterns.	Correlation Spectroscopy (COSY) is a two-dimensional NMR technique that correlates proton chemical shifts through scalar coupling (J-coupling), revealing which protons are magnetically coupled and hence bonded through multiple bonds. Developed by Aue, Bartholdi, and Ernst in 1976, COSY became one of the most important tools in structural elucidation, enabling chemists to map out proton connectivity patterns and deduce molecular topology without isotopic labeling.	Nuclear Overhauser Enhancement Spectroscopy (NOESY) is a 2D NMR technique that detects through-space dipolar coupling between protons, rather than through-bond scalar coupling. Introduced by Macura and Ernst in 1981, NOESY reveals which protons are spatially close in the three-dimensional structure, independent of bonding connectivity. This makes NOESY invaluable for determining molecular conformation, assigning stereochemistry, and elucidating protein folds.