This Structure Data File (SDfile) is associated with the thesis: Kois, A. "Synthetic approaches to heliangolide sesquiterpenes." and http://library.ua.edu/vwebv/holdingsInfo?bibId=741315 It is distributed by the University of Alabama Libraries. The SDfile is licensed under a Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). Chemical Structure Data Files can be viewed/processed with most cheminformatics toolkits and stand-alone software packages: See https://en.wikipedia.org/wiki/Cheminformatics_toolkit. Note that this is the archived non-standardized chemical substance data. If you are looking for the standardized data" see the UA Libraries PubChem Data Source: https://pubchem.ncbi.nlm.nih.gov/source/15645. The specific substances associated with this data set are indicated by the local DATSOURCE_REGID identifiers within the SDfile. These identifiers can be used to cross-reference the data within PubChem. Moreover, additional information about the structure data compiling workflow is available on the UA Libraries GitHub Chemical Structures Project Page: https://github.com/ualibweb/UALIB_ChemStructures