In this study, (E)‐4‐{4‐[(1‐oxo‐3,4‐dihydronaphthalen‐2(1H)‐ylidene)methyl]phenoxy}phthalonitrile (4) and its phthalocyanine derivatives (5–8) were synthesized for the first time. Aggregation behaviors of the novel soluble phthalocyanines in organic solvents were investigated. In addition, the efficiency of 1O2 production of (5) and ZnPc (6) was investigated. The singlet oxygen quantum yields (ΦΔ) for 2HPc (5) and ZnPc (6) were found to be 0.58 and 0.83, respectively. Additionally, novel phthalocyanines (5–8) were investigated for their ability to inhibit enzymes. They exhibited a highly potent inhibition effect on human carbonic anhydrase I and II (hCA I and II) and α‐glycosidase (α‐Gly) enzymes. Ki values are in the range of 2.60 ± 9.87 to 11.53 ± 6.92 µM, 3.35 ± 0.53 to 15.47 ± 1.20 µM, and 28.60 ± 4.82 to 40.58 ± 7.37 nM, respectively. The calculations of the studied molecule at the B3LYP, HF, and M062X levels in the 6–31G basis sets were made using the Gaussian package program. Afterward, the interactions occurring in the docking calculation against a protein that is the crystal structure of hCA I (PDB ID: 2CAB), the crystal structure of hCA II (PDB ID: 5AML), and the crystal structure of α‐Gly (PDB ID: 1R47), were examined. Following that, Protein–Ligand Interaction Profiler (PLIP) analysis was used to look at the interactions that occurred during the docking calculation in further detail.