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Combining the Power of J Coupling and DP4 Analysis on Stereochemical Assignments: The J-DP4 Methods
Nicolás Grimblat1, José A Gavín2, Antonio Hernández Daranas2,3
1Instituto de Química Rosario (IQUIR, CONICET-UNR) and Facultad de Ciencias Bioquímicas y Farmacéuticas , Universidad Nacional de Rosario , Suipacha 531 , S2002LRK Rosario , República Argentina.
Abstract:
A systematic study to include 3 JHH couplings into DP4 formalism ( J-DP4) led to the development of three alternative strategies. The d J-DP4 (direct) approach involves a new DP4-like equation including an additional probability term given by 3 JHH. The i J-DP4 (indirect) approach explores the original DP4 method with a restricted conformational search. Despite both strategies performing better than DP4, their combined use (i J/d J-DP4) provided the best results, with a 2.5-fold performance improvement at similar or lower computational cost.
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