Computational Methods

The theoretical ECD curves of compounds **1**–**5** were calculated by using Gaussian 09, Revsion E.01. software. Conformational searches were performed using Spartan'14 software with the Molecular Merck force field (MMFF). ECD spectra of conformers with a Boltzmann distribution over 2% were calculated via the TD-DFT method at the B3LYP/6.311+G (d,p) level in MeOH. According to a Gaussian band shape with a 0.2 eV exponential halfwidth from the dipole-length dipolar and rotational strengths, the theoretical ECD spectra were generated using the SpecDis 3.0.

## *4.4. Antifungal Activity Assays*

The assays tested for the presence of microorganisms. The in vitro antifungal activity of compounds **1**–**5** was tested against a panel of laboratory control strains belonging to the Bioresource Collection and Research Center (BCRC) in Hsinchu, Taiwan, namely, the fungal organisms *Aspergillus niger* (BCRC-31512), *Penicillium italicum* (BCRC-30567), *Candida albicans* (BCRC-21538), and *Saccharomyces cerevisiae* (BCRC-20822).

#### 4.4.1. Via Disk Diffusion Assay

Antifungal susceptibility testing of the isolated compounds was performed with the following strains: *Aspergillus niger*, *Penicillium italicum*, *Candida albicans*, and *Saccharomyces cerevisiae* using the disk diffusion method and the following CLSI guidelines were applied: M44-A and M44-S2 for yeasts [40,41] and M-51P for filamentous fungi. A standard disk of ketoconazole was used as a positive control, while a disk imbued with 50 μL of pure DMSO was used as a negative control. The diameters of the inhibition zones were measured in millimeters by means of a slide caliper. Each test was performed in triplicate, and the results were analyzed for statistical significance [40–42].

#### 4.4.2. Via Broth Dilution Assay

The MIC determination for the antifungal assay was performed according to the Clinical and Laboratory Standard Institute (CLSI) using the broth dilution assay method [43–45]. Extract stock solutions and partitions were prepared in 5% DMSO, and twofold serial dilutions were prepared in RPMI in 96-well microtiter plates (Corning Incorporated, Corning, NY, USA). The final concentrations ranged from 0.98 to 2.000 g mL−1. Test organisms (100 μL) were added to each well in microtiter plates. The growth control contained medium and inoculum. Blank controls contained medium only. The microtiter plates were then incubated at 35 ◦C and the endpoints were read after 48 h. The lowest concentration for each test compound at which color change occurred was recorded as its primary MIC value. The average of primary values from three individual tests were calculated, and the average was taken as the final MIC value for each of the test compounds.
