Boron-Containing Chlorins and Tetraazaporphyrins: Synthesis and Cell Uptake of Boronated Pyropheophorbide A Derivatives

Abstract

The literature on the synthesis and the biological properties of boron-containing chlorins and phthalocyanines is reviewed. A series of homologous derivatives of pyropheophorbide A is described. The compounds contain the B(12)H(11)SH(2-) cluster attached to the single carboxyl group and vary in the length of the alkyl chain (methyl, propyl, pentyl, heptyl and nonyl) attached via an ether linkage to the former vinyl group. Cellular uptake was found for all derivatives except the nonyl sidechain. The compounds were moderately cell-toxic. Localization in lysosomes could be excluded; the compounds localized probably in the mitochondria.

New functionalized mercaptoundecahydrododecaborate derivatives for potential application in boron neutron capture therapy: Synthesis, characterization and dynamic visualization in cells

“…For this purpose, numerous BSH-derivatives of biomolecules (e.g. pophyrins, nitroimidazoles, sugars, chlorins, and lipids) have been synthesized to date [16][17][18][19][20][21][22]. The goal of these efforts is the development of new boron delivery agents that are able to reach the stage for evaluation in a phase I clinical biodistribution study.…”

“…Bis(tetramethylammonium-cyanoethyl-thioetherundecahydro-closo-dodecaborate (5), azides (C 6 H 5 CH 2 N 3 , p-Br-C 6 H 4 CH 2 N 3 , m-OMe-C 6 H 4 CH 2 N 3 ), and 1,2-O-distearoyl-sn-3-glycerol (13) were prepared as described in the literature [15,20,40]. Analytical thin layer chromatography were removed by filtration, and the product was triturated with ether.…”

Polyhedral Boranes for Medical Applications: Current Status and Perspectives

“…More recently, syntheses of anionic boron hydride derivatives of the naturally occurring porphyrin systems pyropheophorbide a, [121] chlorine e6, [22b-22c,122] and bacteriochlorin p [123] have been reported.…”

Physical modification of carbon nanotubes with a dendrimer bearing terminal mercaptoundecahydrododecaborates (Na2B12H11S)

“…The functionalization of dodecaborates has attracted much attention, both for the development of boron neutron capture therapy (BNCT),[1] where 10 B nuclei capture thermal neutrons to emit 7 Li nuclei and alpha particles that destroy cancer cells. Increasing focus has been placed on the conjugation of the thiol‐substituted B 12 ‐cluster mercaptoundecahydro‐ closo ‐dodecaborate (Na 2 [B 12 H 11 SH]; BSH)[2] with biomolecules (eg, porphyrins,[3] nitroimidazoles,[4] sugars,[5] chlorins,[3b,16] and lipids[7]) by thiol derivatization. This is mostly due to the fact that BSH offers great biological advantages relative to the related dicarba‐ closo ‐dodecaborane (C 2 B 10 H 12 ; “carborane”) analogues, which includes higher boron content, ionic nature, higher solubility in water, significantly lower toxicity based on its boron content, and its clinical use in the treatment of cancer (BNCT) [1a].…”