Table 4.
Antimicrobial activity of natural caged xanthones: scortechinones and prenylated.
| No. | Name/Structure | a | Antimicrobial Activity (MIC) |
|---|---|---|---|
| 16N | Scortechinone A
|
+18° (0.028) | S. aureus (128 µg/mL); S aureus SK1 (128 µg/mL); MRSA (128 µg/mL) |
| 17N | Scortechinone B
|
−105° (0.095) | S. aureus (8 µg/mL); S aureus SK1 (2 µg/mL); MRSA (2 µg/mL) |
| 18N | Scortechinone C
|
−107° (0.014) | S. aureus (32 µg/mL); S aureus SK1 (32 µg/mL); MRSA (32 µg/mL) |
| 19N | Scortechinone D
|
+222° (0.018) | S. aureus (>256 µg/mL); S aureus SK1 (>256 µg/mL) |
| 20N | Scortechinone E
|
−240° (0.025) | S. aureus (>256 µg/mL); S aureus SK1 (>256 µg/mL) |
| 21N | Scortechinone F
|
−333° (0.015) | S. aureus (16 µg/mL); S aureus SK1 (4 µg/mL) |
| 22N | Scortechinone G
|
−95° (0.021) | S. aureus (>64 µg/mL); S aureus SK1 (>64 µg/mL) |
| 23N | Scortechinone H
|
−120° (0.025) | S. aureus (>64 µg/mL); S aureus SK1 (4 µg/mL) |
| 24N | Scortechinone I
|
+43° (0.023) | S. aureus (8 µg/mL); S aureus SK1 (8 µg/mL) |
| 25N | Scortechinone J
|
−200° (0.015) | S. aureus (32 µg/mL); S aureus SK1 (8 µg/mL) |
| 26N | Scortechinone K
|
+48° (0.021) | S. aureus (128 µg/mL); S aureus SK1 (128 µg/mL) |
| 27N | Scortechinone L
|
−176° (0.017) | S. aureus (>64 µg/mL); S aureus SK1 (>64 µg/mL) |
| 28N | Scortechinone M
|
−353° (0.017) | S. aureus (32 µg/mL); S aureus SK1 (32 µg/mL) |
| 29N | Scortechinone N
|
−263° (0.019) | S. aureus (32 µg/mL); S aureus SK1 (32 µg/mL) |
| 30N | Scortechinone O
|
+77° (0.013) | S. aureus (>128 µg/mL); S aureus SK1 (>128 µg/mL) |
| 31N | Scortechinone P
|
+83° (0.012) | S. aureus (32 µg/mL); S aureus SK1 (16 µg/mL) |
| 32N | 2-isoprenylforbesione
|
MRSA USA300 SF8300 (7.20 mm b; >400 µM); MSSA ATCC 25923 (7.56 mm b; 400 µM) | |
| 33N | Deoxygamboginin
|
MRSA USA300 SF8300 (6 mm b); MSSA ATCC 25923 (6 mm b) | |
| 34N | Hanburin
|
MRSA USA300 SF8300 (6 mm b); MSSA ATCC 25923 (6 mm b) | |
| 35N | Forbesione
|
MRSA USA300 SF8300 (7.97 mm b; >400 µM); MSSA ATCC 25923 (7.86 mm b, 200 µM) | |
| 36N | Dihydroisomorellin
|
MRSA USA300 SF8300 (6 mm b); MSSA ATCC 25923 (6 mm b) |
MIC: Minimum inhibitory concentration; MRSA: Methicillin-resistant S. aureus; MSSA: Methicillin-sensitive S. aureus; a Specific rotation measured in methanol; b The antimicrobial studies were determined using the disc diffusion method, where the inhibitory growth zones inhibition caused by the tested compounds is expressed in millimeters.