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Structure Elucidator Tutorial Freeware: a free software package at the undergraduate and graduate levels This manuscript covers various exercises of using a free CASE (computer-assisted structure elucidation) software application “Structure Elucidator”. The purpose of these exercises is to use elucidation software to quickly explore potential candidates given a set of NMR data and a molecular...

H. Zhang et al observed interesting signals from very minor constituents from F. virosa in their MS analysis. A further fractionation of the fractions returned two extra new alkaloids, one of which, Flueggether A(molecular formula C25H30N2O5), is the first example of Securinega alkaloid oligomers which features an ether bond linkage.

The authors reported the production and structure characterization of the novel sesterterpene Astellifadiene. Analysis of the 1H-1H COSY, HMBC, and NOESY correlations established the planar structure as an unprecedented 6-8-6-5-membered tetracyclic ring system. The use of NMR analyses combined with the crystalline sponge method facilitated the unambiguous determination of the Astellifadiene structure (molecular formula C25H40).

Ni et al investigated Cephalotaxus mannii Hook f. which led to the isolation of three new diterpenoids, namely, mannolides A−C, and two new Cephalotaxus troponoids. We used the example of Mannolide A (molecular formula C20H24O5) to challenge our ACD/Structure Elucidator Suite software.

From investigating the constituents of Sarcandra glabra, P. Wang et al isolated a pair of structurally-related terpene lactones, sarglaperoxides A and B. The original experimental data related to Sarglaperoxide A (molecular formula C23H28O5) were used to challenge ACD/Structure Elucidator Suite and determine if the software could reliably elucidate this novel structure.

Bautista et al reinvestigated the chemical composition of S. amarissima. As a result, Teotihuacanin (molecular formula C20H20O6), an unusual rearranged clerodane diterpene with a new carbon skeleton containing a spiro-10/6 bicyclic system, was isolated from the leaves and flowers of Salvia amarissima.

Ruthmycin (molecular formula C21H22O7) possesses an unprecedented signature C3 bridge and a corresponding fused six-member ring. In the context of known frenolicin-type scaffolds, the presence of a C-3/C-4 double bond is also unprecedented.

H. Zhang et al observed interesting signals from very minor constituents from F. virosa in their MS analysis. A further fractionation of the fractions showing the interesting MS peaks returned two extra new alkaloids, one of which, Flueggether A (molecular formula C25H30N2O5) is the first example of Securinega alkaloid oligomers which features an ether bond linkage.

Callyspongiolide Macrolides have been reported from various marine macroorganisms, but are especially prominent for marine sponges. Many macrolides display potent anti-proliferative properties against cancer cells, making them promising leads for the development of new chemo-therapeutic agents. Due to their unusual structures and pronounced bioactivity, these compounds continue to be exciting targets for realizing a total...

Tronoharine was isolated in a small amount as a minor alkaloid from a sample of T. corymbosa and given a proposed structure. In a more recent work, it was obtained in a more significant amount, which enabled the authors to reevaluate the previously proposed structure. Structure Elucidator Suite was used to confirm the newly proposed structure of Tronoharine ((molecular formula C21H24N2O2).