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A variety of 1,8(11),15(18),22(25)- and 2,9(10),16(17),23(24)-tetra-substituted and 2,3,9,10,16,17,23,24-octa-susbtituted Zn(II) phthalocyanines, bearing dialkylaminophenoxy and trialkylammoniumphenoxy groups, have been synthetized, characterized and tested as photosensitizers against S. aureus, E. coli and C. albicans. All phthalocyanines exhibited intense absorption bands in the phototherapeutically useful 670-700 nm region, with a molar extinction coefficient of the order of 10⁵ M^-1.cm^-1. All derivatives bearing positive charges showed a good photosensitizing efficiency (causing a greater than 4 log reduction in cell survival), as well as a high quantum yield for generation of singlet oxygen. Variations of the chemical structure appeared to strongly affect both the physicochemical properties and the phototoxic activities against microorganisms.

This paper is a summary of the lecture Michael Hanack gave at the 5th ICPP meeting in Moscow. A new method for the preparation of phthalonitriles is reported which makes the syntheses of substituted phthalocyanines much easier. Then the generation of highly reactive dehydrophthalocyanines using different methods is described. The reaction of these intermediates with dienophiles and various solvents is also discussed. In the last section, the syntheses of tetra- and octa- Zn phthalocyanine and -naphthalocyanine carbohydrate conjugates, which will be used for photosensitizers in PDT, is reported.

The first part of this review summarizes methods for the syntheses of mono-, di-, and tetra-substituted glycosylated phthalonitriles, which are the main starting materials for the preparation of the corresponding glycosylated metal phthalocyanines. In the second part the preparation of symmetrically and unsymmetrically tetra- and octa- glycosylated zinc phthalocyanines in which the sugar is attached either anomerically or via another one of its OH-groups to the phthalocyanine macrocycle as well as other structurally different glycosylated metal phthalocyanines are reviewed.

Interaction of isomeric 4-nitro- or 3-nitrophthalonitrile with triethyl phosphonoacetate, diethyl cyanomethylphosphonate or tetraethyl methylenediphosphonate in basic conditions resulted in regioselective C-nucleophilic oxidative substitution of hydrogen ortho-located to nitro group, new phthalonitriles with diethoxyphosphorylmethyl or bis(diethoxyphosphoryl)methyl group were isolated in modest yields. In the same conditions one chlorine atom of tetrachlorophthalonitrile was regioselectively substituted with triethyl phosphonoacetate. In basic conditions, both parent phthalonitriles and corresponding zinc phthalocyanines with ortho-located nitro and diethoxyphosphoryl substituted methyl groups are involved in reversible acid-base interaction accompanied with large bathochromic shift of their long wavelength absorption maxima in visible or NIR region, correspondingly. Formation of tetraazachlorin- and tetraaza(iso)bacteriochlorin-like anions is proposed for explanation of this unprecedent bathochromic shift for phthalocyanines.

Boron subphthalocyanines (BsubPcs) are versatile molecules with advantageous properties for applications. The BsubPcs are synthesized by the cyclotrimerization of a phthalonitrile and are composed of three isoindole subunits bound by three aza-/imine-bridging nitrogens. There are a variety of BsubPc derivatives shown within the literature due to the differentiation of a phthalonitrile precursor. The differentiation of a phthalonitrile enables the peripheral functional groups. The BsubPcs can be derivatized in two steps: First step is the cyclotrimerization of a phthalonitrile in the presence of a strong Lewis Acid, typically a boron trihalide (BX3) and enables a remaining axial substituent that is a B-X${}_a$ bond; second step is optional, the B-X${}_a$ bond can react with a nucleophile and results in B-X${}_b$. If the starting phthalonitrile is asymmetric, it will result in a combination of isomers. For this study, our approach is to have bromine substituents and to study their physical properties to see if applicable to organic electronic applications; chlorine and fluorine have been in past studies as halogens are unique and variations may present useful tools as they are known for electronegativities. The general phthalonitrile with no substitutions is produced in industry from $o$-xylene. There are a variety of ways to synthesize other phthalonitriles with halogens. However, phthalonitriles can also be made by a method that has the most versatility with its substituents and can start with phthalic acid and go to phthalic anhydride to phthalimide to phthalamide and final to phthalonitrile; it is also possible to synthesize a phthalimide directly from phthalic acid, and this is part of this study as we were focusing on bromination, we also wanted to optimize the synthetic pathways to brominated phthalonitriles, and we took an engineering perspective and for this study, we wish to show you.