Synthesis of texaphyrin conjugates

Abstract

This paper summarizes recent synthetic efforts devoted to the generation of new, second-generation texaphyrin-type drugs, specifically species that involve known or potential anticancer agents covalently attached to a tumor-localizing texaphyrin core. Particular emphasis will be placed on the strategies needed to prepare such systems, as well as on the choice of active group being subject to attachment.

Quantum chemical study of the autoxidation of ascorbate

“…Reactions I‐IV characterize possible autoxidation reactions of AscH − (I), Asc (II), AscH (III), and Asc (IV). A comparison of reactions I–IV provides information on the most favored ascorbate autoxidation reaction for further evaluations of mechanistic cycles as proposed, for example, by Magda et al for texaphyrin catalysis and whether AscH − really is the ascorbate species involved in the catalyzed step (cf. Supporting Information).…”

“…One specific texaphyrin containing Gd (motexafin gadolinium, refered to as Gd‐Tex ) is assumed to act as a redox mediator in the presence of antioxidants like ascorbate (cf. Supporting Information for details) . To be able to better understand the role of such catalysts the mechanism of the uncatalyzed autoxidation process of ascorbic acid and its derivatives, as well as the concomitant formation of ROS has to be studied first.…”

“… Simplified mechanistic scheme of a redox cycling mechanism involving ascorbic acid derivatives adapted from a more extensive one by Magda et al…”

“…All in all there still is a need for studies regarding the oxidation behavior of ascorbate species to understand the physiological functionality of ascorbate itself. Our present work contributes by providing theoretical data for the reaction energies and corresponding Gibbs energies of all possible ascorbate autoxidation reactions and possible reaction sequences involved, for example, in the proposed mechanism for the anti‐cancer drug Gd‐Tex . In vivo many of the reactions studied here are part of rather complex redox cycles, for example, the glutathione‐ascorbate cycle, and involve several enzymes .…”

CALCULATOR FOR FINDING COMPOSITION OF (Me1)x1(Me2)x2(CcHhNnOo)x3(NO3)x4(H2O)x5(Cl)x6 TYPE COMPLEX FROM ELEMENTAL ANALYSIS DATA

“…Moreover the absence of a group means that appropriate components of x for all rows are equal to zero. The generation process of the matrix P excludes the components vectors which do not ensure satisfaction of the condition of electrical neutrality (2). The results of substitution of the vectors x being rows of the generated matrix P into Eq.…”