Ageladine A dihydrochloride, derived from the marine sponge Agelas nakamurai, serves as a matrix metalloproteinase (MMP) inhibitor with anti-angiogenic properties. It inhibits MMP-2, MMP-1, MMP-8, MMP-9, MMP-12, and MMP-13, with IC50 values of 4.65 μM, 2.79 μM, 907.12 nM, 1.83 μM, 767.57 nM, and 1.09 μM, respectively. As a pH-sensitive membrane-permeable dye, it emits fluorescence in the blue-green range when excited by ultraviolet light, with a maximum absorption peak at 370 nm. Additionally, Ageladine A dihydrochloride is used as a reliable and stable fluorescent pH sensor to detect intracellular pH changes.