Short Lecture “Application of DFT calculation for structure elucidation of selected alkaloids”

Structural elucidation has always been challenging and misassignment remains an issue in the field of natural products chemistry [1]. The growing interest in discovering unknown, complex natural structures accompanies the increasing awareness concerning misassignments in the community. The combination of various spectroscopic methods with quantum chemical calculations has gained popularity in recent years [1]. In this work, we demonstrated for the first time its power to revise the structure of macaridine and to fully elucidate the structure of four newly isolated Amaryllidaceae alkaloids (O-demethyl- norlycoramine, 2-epi-pseudolycorine, 2β,10bα-dihydroxy-9-O-demethyl-homolycorine, 9-de-O-methyl- 11β-hydroxy galanthamine) and two known epimers in an epimeric mixture of 6-hydroxyhippeastidine [2] [3]. DFT calculation of chemical shifts was first performed to assist the assignment of planar structures. Furthermore, relative and absolute configurations were established in three different ways by computer-assisted structure elucidation (CASE) coupled with ORD/ECD/VCD spectroscopy.

 

MissingLinkText

Conflict of Interest

The authors declare no conflict of interest.

• References

• 1 Chhetri B.K., Lavoie S., Sweeney-Jones A.M., Kubanek J.. Nat. Prod. Rep 2018; 35 (06) 514-531
• 2 Le HTN, Van Roy E, Dendooven E, Peeters L, Theunis M, Foubert K, Pieters L, Tuenter E.. Phytochemistry 2021; 190: 112863
• 3 Le N.T.H., Vermeyen T., Aerts R., Herrebout W.A., Pieters L., Tuenter E.. Molecules 2023; 28: 214

Publication History

Article published online:
16 November 2023