Preparation and Properties of Some Phthiocol Inner Complexes¹

The Metal Cation Chelating Capacity of Astaxanthin. Does This Have Any Influence on Antiradical Activity?

“…Likewise, when two lead ions are coordinated to the oxygen atoms instead of to the carbon atoms, the resultant [ASTA-Pb 2 ] +4 complex is almost two hundred kilocalories per mol more stable than other isomers. Similar values (not presented here) for other metals such as Cu +2 were found, in agreement with previous results about the formation of complexes with metal ions such as Cu(II) with o-hydroxyquinone, by coordinating with the two oxygen atoms [ 45 , 46 ]. It is possible to conclude from these results that the most stable isomers are those where the metal atoms bond directly with the oxygen atoms.…”

The behavior of metal complexes in aqueous solutions

“…Color in chelate compounds seems to be due primarily to the structure of the compound and to the nature of the polarizable valence bond system, rather than to the type of metal involved. This is strikingly illustrated by the work of Smith and co-workers (31,32,33) on metal chelates of o-quinone monoxime, o-hydroxyazo dyes, o-hydroxyquinones, and 1-hydroxyanthraquinone illustrated schematically by formulas XXVII, XXXI, XXVIII, and XXIX, respectively. The absorption spectra of these compounds are quite characteristic /M/n (XXIX) Metal chelate of 1-hydroxyanthraquinone for the chelate, being quite different from those of the organic compound and of the aquo metal ion.…”

The Chemistry of the Phthalazines.

“…While the phenomenon is observable without them, certain substances act as very strong promoters or accelerators: hemoglobin 169, 188); certain plant chemicals (124,150); certain inner complex salts such as phthalocyanines (26,150,174) and salicylaldehyde-ethylenediamine-ferric chloride (174, 188); and various metallic ions -cupric, ferrous, manganous, cobaltous, and cobaltic, but not nickel (63,161,166,176). There are also a few specific inhibitors: potassium cyanide, sodium sulfide, hydroquinone, acetone, pyridine, phenol, and others (186, 187).…”

“…§ Prepared from 6,7-dichlorophthalhydrazide with ammonia and cuprous iodide (46). presence of reducing agents (91), and similar tests for the presence of traces of ferrous, cobaltous, and cupric ions, and, with suitable precautions, blood (63,123,161,162).…”

“…Certain mercaptophthalazines have been suggested and patented as rubber accelerators (4). Luminol finds application in the qualitative determination of minute quantities of various ions and of blood (63,91,123,161,162), and also serves as a readily available reagent for the study and demonstration of the phenomena of chemiluminescence and chemifluorescence. The study of the synthesis of other phthalhydrazides has contributed to these latter studies, since Drew has observed a correlation between the tendency toward phthalhydrazide formation as opposed to the formation of the isomeric N-aminophthalimides and the intensity of chemiluminescence (41).…”