'BLACK' PORPHYRINS AND METALLOPORPHYRINS

摘要

Disclosed are a compound of formula (I), wherein R1, R2 are H or alkyl, R3 is aryl, and M is a metal (ion) or 2 H, and n1, n2, n3, n4 = 0, and allied compounds as well as methods for obtaining the same. In said compounds, the absorption spectrum is shifted to greater wavelengths.