Ultraviolet-Guided Isolation of Coumarins and Benzofuran Derivatives From Fig (Ficus carica L.) Leaves and Their Bioactivities.

Although fig leaves are widely used for dermatological treatment in traditional medicine, research on the bioactivity of their components is limited. In this study, an ultraviolet-guided approach was employed to isolate 2 novel benzofurans (1-2), 12 known benzofurans (3-14), and 13 known coumarins (15-26a/26b). Compounds 4-10, 13-14, 17, 20, 24, and 26a/26b were detected in fig leaves for the first time. Their structures were elucidated through comprehensive spectral analysis, 1-phenyl-3-methyl-5-pyrazolone (PMP) derivatization, and literature comparison. The absolute configurations of compounds 18, 22-24, and 26a/26b were determined using the Snatzke method and electronic circular dichroism analysis. Compounds 4, 6, and 18 exhibited antimicrobial activity in vitro against Candida albicans and Staphylococcus aureus with MIC/MBC values ranging from 250 to 2000 µM. Compound 16 exhibited significant melanogenic activity, yielding a relative melanin content of 147.7% (p < 0.0001). Compounds 15 and 22 showed moderate melanogenic activity, resulting in relative melanin contents of 118.1% and 119.9% (p < 0.05), respectively.