Texaphyrin

Pharmacyclics, Inc., a publicly traded company begun by Sessler, licensed the technology behind texaphyrins from the university to develop commercial and medical uses for the molecules.

Next, the benzyl groups are cleaved via hydrogenolysis yielding diacid (III) which is subsequently converted to the aldehyde via a decarboxylation-formylation sequence similar to a Clezy formylation.

[7] More recently the Pb and Bi complexes have drawn attention from the Sessler groups as metal centers that could provide a more diverse array of biological applications, but little outside exploration has been done.

[10] Texaphyrins have an advantage over traditional porphyrins as chemotherapeutics due to the fact they are pentapyrrolic rather than the classical tetrapyrrolic allowing for a much wider range of metal centers that vary in both atomic radius and oxidation state.

This ease of reduction allows texaphyrins to act as sort of redox shuttles with the ability to produce reactive oxygen species which can subsequently induce apoptosis, providing promise as a therapeutic when localized in cancer cells.

This MRI active property of texaphyrins has also led the Sessler group to explore the possibility of conjugating on existing platinum-based chemotherapeutics in order to help monitor delivery.

[13] Despite all of these promising results the FDA gave non-approval for the texaphyrin Motexafin gadolinium shortly after finishing phase 2 clinical trials for the treatment of non-small cell lung cancer with brain metatheses, however the exact reason for its failure was not stated.