Characterization of Leptazolines A–D, Polar Oxazolines from the Cyanobacterium Leptolyngbya sp., Reveals a Glitch with the “Willoughby–Hoye” Scripts for Calculating NMR Chemical Shifts
- Jayanti Bhandari NeupaneJayanti Bhandari NeupaneDepartment of Chemistry, University of Hawai‘i at Ma̅noa, 2545 McCarthy Mall, Honolulu, Hawaii 96822, United StatesMore by Jayanti Bhandari Neupane
- Ram P. NeupaneRam P. NeupaneDepartment of Chemistry, University of Hawai‘i at Ma̅noa, 2545 McCarthy Mall, Honolulu, Hawaii 96822, United StatesMore by Ram P. Neupane
- Yuheng LuoYuheng LuoDepartment of Chemistry, University of Hawai‘i at Ma̅noa, 2545 McCarthy Mall, Honolulu, Hawaii 96822, United StatesMore by Yuheng Luo
- Wesley Y. YoshidaWesley Y. YoshidaDepartment of Chemistry, University of Hawai‘i at Ma̅noa, 2545 McCarthy Mall, Honolulu, Hawaii 96822, United StatesMore by Wesley Y. Yoshida
- Rui SunRui SunDepartment of Chemistry, University of Hawai‘i at Ma̅noa, 2545 McCarthy Mall, Honolulu, Hawaii 96822, United StatesMore by Rui Sun
- Philip G. Williams*Philip G. Williams*E-mail: [email protected].Department of Chemistry, University of Hawai‘i at Ma̅noa, 2545 McCarthy Mall, Honolulu, Hawaii 96822, United StatesMore by Philip G. Williams
Abstract

The bioactivity-guided examination of a Leptolyngbya sp. led to the isolation of leptazolines A–D (1–4), from the culture media, along with two degradation products (5 and 6). Density functional theory nuclear magnetic resonance calculations established the relative configurations of 1 and 2 and revealed that the calculated shifts depended on the operating system when using the “Willoughby–Hoye” Python scripts to streamline the processing of the output files, a previously unrecognized flaw that could lead to incorrect conclusions.
Cited By
This article is cited by 2 publications.
- María M. Zanardi, Maribel O. Marcarino, Ariel M. Sarotti. Redefining the Impact of Boltzmann Analysis in the Stereochemical Assignment of Polar and Flexible Molecules by NMR Calculations. Organic Letters 2020, 22 (1) , 52-56. DOI: 10.1021/acs.orglett.9b03866.
- Patrick H. Willoughby, Matthew J. Jansma, Thomas R. Hoye. Addendum: A guide to small-molecule structure assignment through computation of (¹H and ¹³C) NMR chemical shifts. Nature Protocols 2020, 9 DOI: 10.1038/s41596-020-0293-9.




