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Abstract We present a method to use long‐range CH coupling constants to derive the correct diastereoisomer from the molecular constitution of small molecules. A set of 792JCHand3JCHvalues collected from a single HSQMBC experiment on a sample of strychnine were used in the CASE‐3D (computer‐assisted 3D structure elucidation) protocol. In addition to the most commonly used3JCHcoupling constants, the subset of 322JCHvalues alone showed an excellent degree of configuration selection. The study is mainly based on comparison of DFT‐calculated2,3JCHvalues with experimental ones, critical for the case of2JCH. But the configuration selection also works well using3JCHvalues predicted from a semi‐empirical Karplus‐based equation limited to H−C−C−C fragments. The robustness, shown using strychnine as a proof of concept, makes theJ‐based CASE‐3D analysis a viable option for the application in fields such as peptide and carbohydrate research, organic synthesis, natural‐product identification and analysis, as well as medicinal chemistry.
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This content will become publicly available on March 1, 2026
A C 0 interior penalty method for the stream function formulation of the surface Stokes problem
We propose aC0interior penalty method for the fourth-order stream function formulation of the surface Stokes problem. The scheme utilizes continuous, piecewise polynomial spaces defined on an approximate surface. We show that the resulting discretization is positive definite and derive error estimates in various norms in terms of the polynomial degree of the finite element space as well as the polynomial degree to define the geometry approximation. A notable feature of the scheme is that it does not explicitly depend on the Gauss curvature of the surface. This is achievedviaa novel integration-by-parts formula for the surface biharmonic operator.
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- Award ID(s):
- 2309425
- PAR ID:
- 10591262
- Publisher / Repository:
- EDP Sciences
- Date Published:
- Journal Name:
- ESAIM: Mathematical Modelling and Numerical Analysis
- Volume:
- 59
- Issue:
- 2
- ISSN:
- 2822-7840
- Page Range / eLocation ID:
- 1177 to 1211
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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