Table 5.

Antimicrobial activity of natural caged xanthones with pyran group.

No.	Name/Structure	${[\mathsf{\alpha }]}_{\mathbf{D}}^{28}(\mathbf{c})$ a	Antimicrobial Activity (MIC or Zone of Growth)
37N	Hanburinone	−62° (0.09)	MRSA (200 µM)
38N	Isomoreollin B	−44° (0.11)	MRSA (200 µM)
39N	Morellin	−600° (0.04)	MRSA (200 µM)
40N	Moreollic acid	−39° (0.22)	MRSA (25 µM)
41N	Morellic acid	−541° (0.19)	MRSA (25 µM); MRSA USA300 SF8300 (19.52 mmb; 12.5 µM); MSSA ATCC 25923 (19.23 mm b; 12.5 µM)
42N	Deoxymorellin		MRSA USA300 SF8300 (6 mm b); MSSA ATCC 25923 (6 mm b)
43N	Isomorellinol		MRSA USA300 SF8300 (8.57 mm b); MSSA ATCC 25923 (7.75 mm b)
44N	Gambogic acid	${[\mathsf{\alpha }]}_{\mathrm{D}}^{20}$(0.17) = −714.1°	MRSA USA300 SF8300 (17.29 mm b; 25 µM); MSSA ATCC 25923 (16.59 mm b; 12.5 µM)

MIC: Minimum inhibitory concentration; MRSA: Methicillin-resistant S. aureus; MSSA: Methicillin-sensitive S. aureus; ^a Specific rotation measured in CHCl₃; ^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.