The chemistry of pyrrolic compounds. XLV. Haematoporphyrin derivative: haematoporphyrin diacetate as the main product of the reaction of haematoporphyrin with a mixture of acetic and sulfuric acids

Abstract

A mixture of acetic and sulfuric acids converts haematoporphyrin into a complex mixture of porphyrins of which the main product has been characterized as the diacetate (1g). Other compounds identified in the reaction mixture were the known vinylporphyrins (1b-d), (1h) and (li) and the isomeric monoacetoxyethyl(monohydroxyethyl)porphyrins (11) and (1m). Analysis of the reaction mixture was complicated by the presence of 1'-ethoxyethyl derivatives (1e) or (1f), (1j) and (1k)which presumably arose by solvolysis of the corresponding acetate with ethanol present in the chloroform used for the chromatographic separation.

Effects of membrane physical parameters on hematoporphyrin-derivative binding to liposomes: A spectroscopic study

“…The standard change in the Gibbs free energy of Hpd transfer from aqueous to lecithin environment is in the range of -1.7 kcal 9 mole ~, based on the effect of DPPC on the polarization, to -2.4 kcal 9 mole 1, using the cholesterol results. Under the drastic conditions employed to produce Hpd, a mixture of acetylation, dehydration (Clezy et al, 1980) and possibly etherification and polymerization products (Dougherty, Potter & Weishaupt, 1984) are formed, and this mixture is usually used in studies and clinical treatment. At pH = 6.5, the core nitrogens are mainly doubly protonated, i.e., neutral, and side chain carboxylic groups are anionic.…”

“…The product was brought into solution in 1 N NaOH and then the pH was adjusted to 7.0. This stock solution, containing a mixture of acetylation and dehydration products (Clezy et al, 1980) was used as is. Egg phosphatidylcholine, cholesterol, dimyristoyl-and dipalmitoylphosphatidylcholine, dicetylphosphate (DCP) and 1,6-diphenyl-1, 3,5-hexatriene (DPH) were purchased from Sigma.…”

Photodynamic effects of haematoporphyrin derivative on synchronized and asynchronous cells of different origin

“…The highest sensitivity is found in mid S. CHO cells have been reported to lack this variation in sensitivity during the cell cycle, when treated with HPD and light (Gomer, 1979(Gomer, , 1980Gomer & Smith, 1980). Both commercially available HP and HPD are chemically impure and consist of several porphyrins with varying hydrophobicity (Bonnett et al, 1978;Clezy et al, 1980;Kessel, 1981). The most hydrophobic component of HPD is rapidly taken up by cells, and is also the most efficient component in introducing photodynamic damage to cells in standard culture experiments (Kessel, 1981;Moan et al, submitted (Sandberg & Romslo, 1981) and a reevaluation of the sensitivity of synchronized cells is necessary.…”

Photosensitization with Derivatives of Haematoporphyrin

“…Since the degree of light scattering increases with decreasing wavelength (Doiron et al 1983, Svaasand 1984, irradiation is usually provided at the longest such absorption band, approx. In 1980, Clezy et al reported that the first step in HPD synthesis resulted in the formation of monoand di-acetates of haematoporphyrin. The 500 nm band can also be used, but scattering effects markedly limit the depth of penetration (Kinsey et al 1981, Van Gemert et al 1985.…”