Phthalocyanines are a group of synthetic, macrocyclic compounds that are structurally similar to porphyrins, the naturally occurring pigments. Their structure consists of four isoindole units linked by nitrogen atoms to form a stable ring. Phthalocyanines are known for their intense colors, chemical stability, and photophysical properties, making them useful in various applications, including dyes, pigments, and as photosensitizers in photodynamic therapy.
