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meso-Tris(3,5-di-tert-butylphenyl)porphyrin (P-H) is bonded with L-phenylalanine (H-Phe-OH) directly at the unsubstituted meso-position of the former and the p-position of phenyl group of the latter to afford chiral porphyrin-amino acid conjugate H-Phe(p-P)-OH. The N-(9-fluorenyl)-methyloxycarbonyl compound, Fmoc-Phe(p-P)-OH, was synthesized without any loss of enantiomeric purity (based on chiral HPLC analysis) from commercially available L-tyrosine and was useful for preparation of the peptides in both liquid and solid phases. Other meso-tetraarylporphyrins possessing multi-amino acid moieties are reported, as well as achiral porphyrin-amino acids readily prepared and their dipeptidyl porphyrin dyads.

An unsymmetrical phthalocyanine based one- and two-photon fluorescence imaging probe that substituted with 4-tert-butylphenoxy and RDGyK moieties was developed and characterized by UV-vis and high-resolution MALDI-TOF/MS. The conjugate is non-aggregated in $N$,$N$-dimethylformamide, with relatively weak fluorescence emission (${\mathrm{\Phi }}_F=$ 0.023) and high singlet oxygen quantum yield (${\mathrm{\Phi }}_{\mathrm{\Delta }}=$ 0.55). Conjugation of the cyclic peptide sequence c(RGDyK) can enhance the cellular uptake towards the DU145 and PC3 cells. While the fluorescence is greatly enhanced in mitochondria, the conjugate is non-cytotoxicity either in dark or upon exposure to red-light with dose up to 12 J.cm${}^{-2}$. The results suggest that this conjugate is a promising multifunctional imaging probe for mitochondria and cancer.

Two mono meso-functionalized [20]di-$p$-benzihomoporphyrins containing $p$-formylphenyl and $p$-iodophenyl groups at meso-position respectively were synthesized by condensing one equivalent of appropriate tetrapyrrane with one equivalent of $p$-formyl benzaldehyde/$p$-iodo benzaldehyde in CH₂Cl₂ under mild acid catalyzed conditions. The meso-formylphenyl and meso-iodophenyl functionalized di-$p$-benzihomoporphyrins were used to synthesize two covalently linked di-$p$-benzihomoporphyrins-BODIPY conjugates. The meso-formylphenyl-functionalized di-$p$-benzihomoporphyrin was converted to corresponding meso-dipyrrolyl substituted di-$p$-benzihomoporphyrin by treating with excess pyrrole under acid catalyzed conditions. In the next step, the meso-dipyrrolyl di-$p$-benzihomoporphyrin was subjected to oxidation followed by BF₂ complexation to afford the directly linked di-$p$-benzihomoporphyrin-BODIPY conjugate. The meso-iodophenyl functionalized di-$p$-benzihomoporphyrin was coupled with ethynyl-functionalized BODIPY under mild Pd(0) coupling condition to synthesize diphenylethyne-bridged di-$p$-benzihomoporphyrin-BODIPY conjugate. The two conjugates were characterized by HR-MS, NMR, absorption, electrochemical, fluorescence and DFT studies. The spectral and electrochemical studies indicated that the two constituents, di-$p$-benzihomoporphyrin and BODIPY units in the conjugates interact weakly and retain their individual characteristic features. DFT studies indicated a possibility of charge transfer between di-$p$-benzihomoporphyrin and BODIPY units in conjugates.